Safety and risk Dietary supplements are more likely to have side effects if you take them in high doses or instead of prescription drugs, or if you take many different supplements. Some supplements may increase the risk of bleeding or, if taken before surgery, may change the response to anesthesia. How do I know if I need a dietary supplement? AT. Many products are marketed as dietary supplements, and it's important to remember that supplements include not only vitamins and minerals, but also herbs and other botanicals, probiotics, fish oil, and other substances.
Some supplements can help ensure that you get the right amounts of essential nutrients or help promote optimal health and performance if you don't eat a variety of foods, as recommended by MyPlate and the Dietary Guidelines for Americans. However, dietary supplements are not intended to treat, diagnose, mitigate, prevent, or cure diseases. In some cases, dietary supplements can have unwanted effects, especially if taken before surgery or with other dietary supplements or medications, or if you have certain health conditions. Don't self-diagnose any health problems.
Work with your healthcare provider to determine the best way to achieve optimal health. Also check with your healthcare provider before taking a supplement, especially if you are taking any medications or other dietary supplements or if you have any health conditions. Where can I find out how much of each vitamin and mineral I need? AT. For a list of all the vitamins and minerals and how much you need, check out the US free online tool.
UU. Just enter a few facts about yourself, including your age, height, and weight. You can also get a list of your daily calorie, protein, and other nutritional needs. Keep in mind that the amounts of vitamins and minerals you need include everything you get from food and beverages; you may or may not need a dietary supplement to reach these amounts.
Talk to your healthcare provider to help you determine what supplements, if any, might be valuable to you. For more detailed information on each vitamin and mineral, read our vitamin and mineral fact sheets. In addition, you can get good sources of information on how to eat well in the Dietary Guidelines for Americans and in ChooseMyPlate. How can I learn more about a particular dietary supplement, such as whether it is safe and effective? AT.
Scientific evidence supporting the benefits of some dietary supplements (p. ex. The manufacturer does not have to prove that the supplement is effective, unlike medications. The manufacturer may say that the product addresses a nutrient deficiency, supports health, or reduces the risk of developing a health problem, if true.
If the manufacturer makes a claim, it must be followed by the following statement: This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Dietary supplements are not intended to treat, diagnose, mitigate, prevent, or cure diseases. Supplements should not replace prescription drugs or the variety of foods important to a healthy diet.
Also, check with your healthcare provider before taking a supplement, especially if you are taking any medications or other dietary supplements or if you have any health conditions. Where can I find information on the use of dietary supplements for a particular condition or disease? AT. Whatever your choice, supplements shouldn't replace prescription drugs or the variety of foods important to a healthy diet. What does the information label on a dietary supplement's supplement tell me? AT.
All products labeled as dietary supplements carry a complementary information label similar to the nutrition facts label found on food products. List the active ingredients and their quantities, as well as other added ingredients such as fillers, binders and flavorings. It also provides a suggested serving size, but you and your healthcare provider may decide that a different amount is more appropriate for you. On the supplement information label, the amounts of vitamins, minerals and other nutrients, such as dietary fiber, are listed as a percentage of the daily value or %DV.
Each nutrient has a DV that applies to all people aged 4 and over. For example, the DV of vitamin C is 90 milligrams (mg) and the DV of vitamin B biotin is 30 micrograms (mcg). The %DV allows you to see how much a product contributes to your approximate daily needs for that nutrient. For example, if a supplement provides 50% of the recommended daily dose of calcium, it provides approximately half of the daily calcium requirement.
The Food and Drug Administration (FDA) has a website that describes the nutrition facts label and the DV in more detail. What is the difference between the recommended daily dose and the recommended daily dose for a vitamin or mineral? AT. Many terms are used to refer to the amount of a particular nutrient (such as calcium or vitamin D) you should eat or the amount of a food or dietary supplement. The two most common are the Recommended Daily Allowance (RDA) and the Daily Value (DV).
The recommended daily doses of a nutrient are the recommended daily intakes for healthy people. They tell you how much of that nutrient you should consume on average each day. RDAs are developed by the Food and Nutrition Board of the National Academies of Sciences, Engineering and Medicine. They vary depending on age, gender, and whether a woman is pregnant or breastfeeding; therefore, there are many different recommended daily doses for each nutrient.
The Food and Drug Administration (FDA) are used on the labels of foods and dietary supplements. For each nutrient, there is a DV for everyone over 4 years old. Therefore, the daily doses are not the recommended intakes, but rather suggest the amount of nutrient that a portion of the food or supplement provides in the context of a total daily diet. DVs tend to equal or exceed the recommended doses for most people, but not in all cases.
The dietary supplement label database has a web page that lists the daily values of all nutrients. What are the upper limits (ULs) for vitamins and minerals? AT. Our bodies need vitamins and minerals for many things, such as breaking down the food we eat, producing bones and DNA, helping muscles contract, and maintaining immunity. However, there's no reason to consume more than you need, and some nutrients can be dangerous in large quantities.
Each vitamin and mineral has a recommended amount, which is what you should eat every day for good health. Most of them also have what's called a “tolerable maximum intake level” or UL. Consuming more than what the UL says can cause health problems. Other vitamins and minerals appear to be safe at any dose, while some have a UL only under certain circumstances.
Stay under the UL every day to get these nutrients to avoid health problems, unless your healthcare provider recommends more. For example, very high doses of vitamin B6 can cause serious nerve damage, and too much iron can be fatal. General guidelines for these nutrients include what you get from foods, beverages, fortified foods (including many breakfast cereals), and dietary supplements. But you're unlikely to exceed the UL in food and beverages alone.
These vitamins and minerals, found naturally in foods and beverages, won't cause any health problems. However, they can do so if you consume amounts higher than the UL through supplements or fortified foods. Only preformed vitamin A has a UL because high amounts can cause health problems, such as birth defects during pregnancy and liver damage. Beta carotene has no UL because high amounts don't cause these problems.
These nutrients have no identified safety issues, even at high doses. However, there's no reason to consume more than the recommended amounts, unless your healthcare provider recommends it. Do you have any more questions? See our vitamin and mineral fact sheets for details on recommended amounts and concentration limit values. Where can I file a complaint about a particular dietary supplement or find the contact information of a supplement company? AT.
To report an illness or injury related to a dietary supplement, talk to your healthcare provider and contact the U.S. To report a complaint related to misleading advertising, fraud, or other consumer protection issues related to a dietary supplement, contact the Federal Trade Commission (FTC). The FTC also has a helpful website with tips for solving common consumer problems that provides links to state, local and national organizations that might be able to help you. If you're having trouble finding the contact information for a dietary supplement manufacturer or distributor, check out our database of dietary supplement labels.
It provides contact information for many dietary supplement companies. Where can I find free and accurate information on vitamins, minerals, herbs and other dietary supplements? AT. A good starting point is the ODS dietary supplement fact sheets, which provide useful information on the ingredients of dietary supplements, including recommended amounts, health effects, safety, and drug interactions. Many of the ODS fact sheets come in three versions: the easy-to-read version for consumers, in English and Spanish, and the more detailed version for health professionals.
Read them online or print a copy. In addition, the Herbs at a Glance fact sheets from the National Center for Complementary and Integrative Health (NCCIH) provide basic information on specific herbs and botanicals: common names, uses, possible side effects, and resources for more information. Where can I find published scientific studies on dietary supplements? AT. You can search for medical and scientific studies on specific dietary supplement ingredients in PubMed.
PubMed is a database of the National Library of Medicine that provides access to more than 30 million citations from MEDLINE biomedical publications, life science journals, and online books. I try to eat well, but sometimes I can't. How do I know if I should take a multivitamin supplement? Our MVM fact sheet discusses the types of MVM available and the possible health effects of MVM, and provides guidance on which type of MVM to choose. Keep in mind that manufacturers are adding some of the vitamins and minerals found in dietary supplements to a growing number of foods, including breakfast cereals and beverages.
As a result, you may be consuming more of these nutrients than you think, and more may not be better. Taking more than you need is always more expensive and can increase the risk of side effects. You may have read about some recent studies that suggest that taking a multivitamin supplement or nutrients such as folic acid, copper and iron is linked to a higher risk of death. For example, in one study, calcium was the only nutrient that reduced the risk of death.
Because the participants in this study were almost all white postmenopausal women, the results cannot be applied to men, younger women, or people of different ethnicities or races. In addition, the study was not a cause and effect study, so it cannot prove that taking supplements causes earlier death. Most other studies do not find a relationship between taking a multivitamin or other nutrient dietary supplement and an increased risk of death. For a personalized list of your nutritional needs, you can use the interactive dietary reference tool for dietary intake from the United States.
I know that carrots are healthy and have a lot of vitamin A. But I've also heard that too much vitamin A can be dangerous, so should I limit the amount of carrots I eat? AT. Vitamin A can be toxic in high doses and cause liver damage and birth defects if a woman is pregnant. However, this only applies to the form of vitamin A called preformed vitamin A or retinol found in animal foods, such as beef liver, milk, dairy products, and some dietary supplements.
Plant foods, such as carrots, spinach, and red peppers, contain a form of vitamin A called beta-carotene. Consuming high amounts of beta-carotene can cause the skin to turn yellow-orange in color, but this condition is harmless. Beta-carotene does not cause birth defects or other more serious effects caused by excessive consumption of preformed vitamin A. So enjoy lots of carrots and other fruits and vegetables without worrying about consuming too much vitamin A.
Do you have any more questions? See our vitamin A fact sheet. Is it common to need vitamin B12 injections? AT. Vitamin B12 is found naturally in a wide variety of animal foods, including fish, meat, poultry, eggs and milk. It is also added to some fortified breakfast cereals and nutritional yeasts.
Most people in the United States get enough vitamin B12 from the foods they eat. However, vitamin B12 deficiency is still common, affecting up to 15 percent of the population. This is mainly because some people, especially older adults and people with certain health conditions, such as pernicious anemia, have problems absorbing vitamin B12 from food. While many of these people can absorb synthetic vitamin B12 that is added to fortified foods and dietary supplements, some cannot.
Therefore, it's possible to have a vitamin B12 deficiency even if you're consuming the recommended amount of vitamin B12 from your diet. Vitamin B12 deficiency is usually treated with injections, so it goes directly to the body and doesn't have to be absorbed like vitamin B12 taken by mouth. My supplement contains 500 mcg of vitamin B12, and the label says it provides between 20 and 30% of the recommended daily dose. Is that correct? It seems too much.
Can vitamin C prevent colds or make them shorter? AT. This is a common question and one that many scientists have tried to answer. Overall, research shows that, for most people, taking vitamin C regularly doesn't reduce the chances of getting the common cold. Vitamin C supplements may slightly shorten the duration of a cold and lessen its severity.
However, taking vitamin C after the onset of cold symptoms doesn't seem to help. Taking too much vitamin C can cause diarrhea, nausea, and stomach cramps. Most adults need 75 to 90 milligrams (mg) of vitamin C a day and should not take more than 2000 mg. Do you have any more questions? See our vitamin C fact sheet.
Should I take a vitamin D supplement? AT. You need vitamin D for strong, healthy bones and to help prevent osteoporosis. Researchers are also studying vitamin D to see if it affects the risk of diseases such as diabetes and cancer, but they don't yet fully understand all of its effects on the body. Most children and adults should receive 15 micrograms (mcg) or 600 international units (IU) a day, while those over 70 need 20 mcg or 800 IU.
Good sources of vitamin D are fatty fish, such as salmon and tuna, and fortified milk. Our bodies also produce vitamin D when our skin is exposed to the sun. It can be difficult to know exactly how much vitamin D you're getting. Your healthcare provider can help you determine if you might need a vitamin D supplement based on factors such as the food you eat, the type of skin, and the amount of sun you're exposed to.
Your healthcare provider can also test your vitamin D blood levels. Do you have any more questions? See our vitamin D fact sheet. What is the difference between vitamin D2 and vitamin D3? AT. Younger adults need 15 micrograms (mcg) or 600 international units (IU) of vitamin D per day, and those over 70 need 20 mcg (800 IU).
This includes what you get from food, beverages, and dietary supplements, plus any vitamin D you can get from sun exposure. Vitamin D is found in some foods, such as fatty fish (such as salmon and tuna), fortified milk, beef liver, cheese, egg yolks and mushrooms, but it can be difficult to get enough. Some people have had their vitamin D levels tested and found that they are low. Unless you are being treated by your healthcare provider, you should not receive more than 100 mcg (4000 IU) of vitamin D a day.
Intakes below this amount are considered safe, so taking a dietary supplement containing 25 mcg (1000 IU) or even 50 mcg (2000 IU) should be safe. However, we recommend that you talk to your healthcare provider to determine if you need a vitamin D dietary supplement and, if so, in how much. I have been taking a vitamin D supplement that contains 400 IU, which is 100% of the recommended daily dose. I just bought another vitamin D supplement that also contains 400 IU, but its label says it provides only 50% of the recommended daily dose.
There's a simple explanation: the supplement you're currently using has the old supplement information label and the one you just bought has the new label. For many years, the recommended daily dose of vitamin D was 400 IU. Therefore, a vitamin D supplement containing 400 IU would provide 100% of the DV. However, research shows that many adults need slightly more vitamin D than previously thought.
Therefore, the FDA increased the recommended daily dose of vitamin D and also changed the units. The new DV is 20 mcg (micrograms), which is equivalent to 800 IU. Because the DV has changed, a 400 IU vitamin D supplement with the new Supplemental Information label provides only half, or 50%, of the DV. On the new label, manufacturers must indicate the amount of vitamin D in mcg, but they can also indicate it in IU to make the transition a little less confusing for consumers.
My cardiologist recommended a 100 IU supplement of natural vitamin E to me. I found a supplement that has 100 mg of vitamin E. Is it the same as 100 IU? AT. No, 100 milligrams (mg) of vitamin E is not the same as 100 international units (IU); units make a difference.
The amount your cardiologist recommended (100 IU) of natural vitamin E is equivalent to 67 mg of vitamin E. This is because 1 IU of natural vitamin E is equivalent to 0.67 mg of vitamin E. As you may have noticed, vitamin E is indicated in mg on the supplement's new information label instead of in IU. It now matches the units used for the recommended intake of vitamin E, which is 15 mg for most adults.
Many people, especially women, take calcium supplements. As you know, it's important to get enough calcium (and vitamin D) for good bone health. And while it's often best to get vitamins and minerals from foods and beverages, some supplements can help you get enough of certain nutrients. It's not clear if calcium affects the risk of cardiovascular disease.
Some studies show that it may protect people from heart disease and stroke. However, other studies have found that some people who consume high amounts of calcium, especially in the form of supplements, may have a higher risk of heart disease. Much of the risk depends on diet, lifestyle, current health, and medical and family history. Talk to your healthcare provider about calcium, bone health, and heart disease to determine what's right for you.
Do you have any more questions? See our fact sheet on calcium. What's the difference between calcium carbonate, calcium citrate, and other forms of calcium supplements? AT. The main difference between different calcium supplements is the form of calcium they contain, and one isn't necessarily better than another for you. The two most common forms are calcium carbonate and calcium citrate.
Calcium carbonate is better absorbed when taken with food. Calcium citrate is well absorbed on an empty or full stomach. In addition, people with low levels of stomach acid (which is more common in people aged 50 and older) absorb calcium citrate more easily than calcium carbonate. One of the most important things to consider about calcium supplements, besides the form of calcium, is how much you should take at one time.
Calcium is best absorbed by the body at doses of 500 milligrams (mg) or less at a time. So, for example, if you take 1000 mg of calcium in supplement form per day, you can divide the dose and take 500 mg at two different times during the day. Some dietary supplements contain high doses of biotin and are promoted for healthy hair, skin and nails. Biotin is a B vitamin found mainly in meat, eggs, fish, nuts and some vegetables.
A biotin deficiency can cause rashes, hair loss and brittle nails, hence the belief that taking additional biotin will produce healthier skin, thick hair and strong nails. But it's not clear if these claims hold up. One of the most common misconceptions about vitamins and minerals is that if a nutrient deficiency causes a particular set of symptoms, taking more of that nutrient will not only reverse those symptoms, but it will also improve it. The reality is that if you're already consuming enough, consuming more doesn't usually help.
Some dietary supplements contain between 2500 and 5000 mcg of biotin, which are very high doses. In some small scientific studies, some people with thin, brittle nails who took high doses of biotin had harder nails. And in some cases, high doses of biotin improved a rare hair disorder in children and rash in infants. However, the results of these studies are too preliminary to recommend biotin for any of these conditions.
Biotin has no upper intake limit because there is no evidence that it is toxic, even at high doses. However, most vitamins and minerals have maximum limits, and consuming too much can be dangerous. Some may also interact with medications or laboratory tests. Biotin, for example, can produce false results in some laboratory tests, including those that measure thyroid hormone levels.
For these and other reasons, we always recommend talking to your healthcare provider about vitamins, minerals, and other dietary supplements to help you determine which, if any, may be valuable. Do you have any more questions? See our biotin fact sheet. I know that vitamin B, folic acid, helps prevent birth defects, so it's important to take it during pregnancy, but why are women supposed to take it before they get pregnant? AT. Yes, getting enough folic acid helps prevent birth defects, especially so-called neural tube defects.
These types of birth defects occur when the neural tube (where the brain and spinal cord are formed) doesn't close properly in the fetus. The neural tube closes very early in pregnancy, only 3 to 4 weeks after conception. This is just when most women realize they're pregnant, so waiting to take folic acid until they find out that you're pregnant could be too late. Do you have more questions about folic acid? See our fact sheet on folate.
Many of the B vitamins, such as vitamin B12, thiamine, and riboflavin, don't seem to be harmful at high doses. Therefore, scientists have not established safe upper limits for these nutrients. However, other B vitamins, such as niacin and vitamin B6, have maximum limits and can cause problems if ingested in excess. This is particularly true for vitamin B6, which has an upper limit of 100 milligrams (mg) per day.
Consuming too much vitamin B6 can cause painful and unsightly patches on the skin, sensitivity to sunlight, nausea, and heartburn. If you take excessive amounts for a year or longer, vitamin B6 can also cause nerve damage and cause you to lose control of body movements. Unless your healthcare provider has recommended a high-dose vitamin B supplement, it's safest to look for supplements that don't provide amounts equal to or greater than the upper limits. Do you have any more questions? See our vitamin B6 fact sheet along with our other vitamin and mineral fact sheets.
Can vitamin B6 reduce PMS symptoms? If you want to try vitamin B6 for PMS, talk to your healthcare provider first. My 17 year old daughter has decided to follow a vegetarian diet. I'm worried that I'm not getting enough iron. Should I take an iron supplement? AT.
Your child's healthcare provider is the best person to help you determine if your child is getting enough iron from her diet or if she could benefit from a supplement. The recommended daily amount of iron is 15 milligrams (mg) for a teenager. While meat, poultry, and seafood are the richest sources of iron, many plant foods, such as beans, nuts, and vegetables, also contain iron. Iron is also added to many breads, cereals, and other fortified grain products.
Vegetarians can get enough iron from food. However, our bodies don't absorb the form of iron found in plant and fortified foods, as well as the form of iron found in animal products. For this reason, vegetarians need to consume almost twice as much iron as non-vegetarians. Our iron fact sheet provides more details, including the recommended daily amounts of iron for different age groups.
Is magnesium helpful for muscle cramps? AT. As with all vitamins and minerals, it's important to get enough magnesium for good health. Muscle cramps are one of the signs of a magnesium deficiency, so if you're not getting enough magnesium, eating more could help. However, in most cases, muscle cramps are caused by other things.
We recommend that you talk to your healthcare provider to determine if muscle cramps or any other symptoms you have may be a sign of a magnesium deficiency or something else. Do you have any more questions? See our fact sheet on magnesium. Can magnesium help prevent migraines? AT. Research shows that people who get migraines tend to have lower levels of magnesium than those who don't.
This suggests, but does not prove, that consuming more magnesium could decrease the likelihood of getting migraines. Can I get enough potassium by eating a banana every day? AT. Bananas have a lot of potassium compared to many other foods, but eating a banana a day alone won't cover your potassium needs. A medium banana has approximately 420 milligrams (mg) of potassium, so you would need to eat at least 6 to 8 bananas to meet the 2600 to 3400 mg of potassium that adults should consume each day.
Obviously, that's not the best approach. Instead, eat a variety of nutritious foods that contain potassium to ensure you get enough of this important nutrient. Do you have any more questions? See our potassium fact sheet. I can't find a potassium supplement that provides a lot of potassium.
Most dietary supplements contain less than 100 milligrams (mg) of potassium, which is only 3 to 4% of the recommended daily amount for adults. This is partly due to reports that some medications that contain potassium can damage the gastrointestinal tract. The Food and Drug Administration (FDA) does not limit the amount of potassium in dietary supplements, but instead requires warning labels on some medications that contain 100 mg of potassium or more. Because of the small amounts of potassium in dietary supplements, you can't rely on them to meet your potassium needs.
This underlines the importance of obtaining potassium by eating a variety of nutritious foods. Can potassium help lower my blood pressure? AT. People with low potassium intake have a higher risk of high blood pressure, especially if they consume a lot of sodium (salt). Therefore, increasing potassium intake, along with decreasing sodium intake, could help lower blood pressure and reduce the risk of stroke.
One way to do this is to follow an eating plan called DASH (Dietary Approaches to Stop Hypertension), which emphasizes potassium in fruits, vegetables and low-fat dairy products. In addition, using salt substitutes that contain potassium instead of common salt helps lower blood pressure. However, it's not clear if this is due to an increase in potassium, a reduction in sodium, or both. Do all salts contain iodine? What about sea salt? Check product labels to see if the salt is iodized or contains iodine (it usually appears as iodide).
But keep in mind that the iodine in salt decreases over time, especially if the salt is stored in a warm, humid place. Therefore, keep iodized salt in a cool, dry place and buy a new container from time to time, such as at the start of each new year. Processed foods, such as canned soups, are rarely prepared with iodized salt, so even if these foods contain salt, the salt probably won't supply iodine. If the manufacturer uses iodized salt, the salt will appear as iodized in the ingredient list on the food label.
For more information about iodine, including health problems that can occur if you consume too little or too much, see our iodine fact sheet and check with your healthcare provider for specific advice. Pregnant women need 220 micrograms (mcg) of iodine a day. Most fruits, vegetables, and other plant foods contain very little iodine (typically less than about 7 mcg per serving). So if you follow a vegan diet or eat few dairy products, seaweed, shellfish, or eggs, you may not get enough iodine.
Also, if you don't use iodized salt, your iodine intake may be low. Our iodine fact sheet contains more information on the importance of iodine during pregnancy and childhood. Some pregnant women in the United States may not get enough iodine. Iodine plays many important functions in the body, including proper bone and brain development.
Talk to your healthcare provider about iodine as part of your prenatal care. Iodine is found naturally in some foods, but amounts vary. Good sources include seaweed, fish and other seafood, and eggs. Iodized salt is another good source of iodine and is available at grocery stores.
However, processed foods, such as canned soups, almost never contain iodized salt. Keep in mind that it's possible to consume too much iodine and this can also cause problems. The safe upper limit for adults is 1,100 mcg per day, but for most people it's not a cause for concern. For example, a 3-ounce serving of baked cod contains approximately 160 mcg of iodine and ¼ teaspoon of iodized salt contains approximately 75 mcg of iodine.
Do you have any more questions? See our fact sheet on iodine. I have macular degeneration and my eye doctor suggested taking a dietary supplement to preserve my vision for as long as possible. Is there research to back this up, and if so, what supplement should I buy? AT. Many dietary supplements promoted for vision or eye health are based on formulations tested in the Age-Related Eye Disease Studies (AREDS), a series of large clinical trials sponsored by the National Institutes of Health.
These studies found that, among people with age-related macular degeneration (AMD) who were at high risk of developing advanced AMD, supplements containing vitamin E, vitamin C, zinc, copper, and beta-carotene or lutein plus zeaxanthin helped reduce the rate of vision loss. Adding the omega-3 fatty acids EPA and DHA to supplements didn't help, but it didn't cause any harm either. The types and quantities of ingredients in eye health supplements available on the market vary. We recommend that you ask your healthcare provider to make a recommendation.
You can also view the specific formulations that were tested in the AREDS studies, along with the results of the study, on the National Eye Institute website. I suffer from migraines and have heard that riboflavin might help. Is it safe to take Riboflavin for migraines? Do you have any more questions? See our fact sheet on Riboflavin. Are Brazil nuts a good way to get enough selenium? AT.
Yes, Brazil nuts are very rich in selenium. However, they contain so much selenium that it can be dangerous to overeat them. Like other vitamins and minerals, selenium has a recommended intake and a safe upper limit. Adults should consume at least 55 to 70 micrograms (mcg) of selenium, but no more than 400 mcg a day.
A nut from Brazil has around 70 to 90 mcg of selenium. So eating one or two Brazil nuts a day is a great way to get enough selenium. But if you eat more than a small handful of Brazil nuts, you could easily exceed the upper limit. Consuming too much selenium on a regular basis can cause several problems, including an upset stomach, garlic smell, hair loss, white-spotted nails, and mild nerve damage.
Do you have any more questions? See our fact sheet on selenium. Can zinc make hair grow? AT. Like all vitamins and minerals, it's important to consume enough zinc for good health. In most cases, hair loss is hereditary and is not related to the amount of zinc you consume.
But it's true that a zinc deficiency can cause hair loss in otherwise healthy people. If you have a zinc deficiency, increasing your intake of zinc to correct the deficiency should help. But this doesn't mean that taking extra zinc will make your hair thicker or longer. Most people in the United States get enough zinc from the foods they eat, about 8 to 11 milligrams (mg) per day for adults.
You can get the recommended amount by eating a variety of foods, such as red meat, poultry, oysters and other seafood, beans, nuts, whole grains, and dairy products. Consuming too much zinc (more than 40 mg per day) in adults can cause problems such as nausea, vomiting, and low copper levels. So, the bottom line is that you should make sure you're getting enough zinc, but not too much. Do you have any more questions? See our fact sheet on zinc.
I recently heard that people can get too much zinc when using denture creams. Zinc is present in some cream adhesives for dentures. Using large amounts of denture creams that contain zinc (well above recommended levels) could result in excessive zinc intake. Too much zinc can cause copper deficiency and nervous system problems, such as numbness and weakness in the arms and legs.
The safe maximum limit for zinc is 40 mg per day. Many denture creams have been reformulated to be zinc-free, but check product labels to make sure. The term “botanical” means “plant”, so botanical supplements contain one or more plant parts, such as the roots of black cohosh or the flowers of echinacea. Botanical supplements, which are often referred to as herbal supplements, are all classified as dietary supplements and are regulated by the U.S.
The Food and Drug Administration (FDA) is different from over-the-counter or prescription drugs. Drugs must be approved by the FDA before they can be sold or marketed, but dietary supplements do not require this approval. Do you have any more questions? See our fact sheet on botanical dietary supplements. What types of botanicals are available? Q.
Do botanical supplements work and are they safe? AT. The amount of scientific evidence on the health effects of botanical supplements varies widely. Because botanical supplements don't require prior approval from the FDA, manufacturers don't have to prove to the FDA that their products “work” before selling them. In addition, botanicals aren't necessarily safe just because they're “natural.”.
The safety of a botanical product depends on many factors, such as its chemical composition, the way it is prepared, the amount used and whether it is taken with other supplements. St. John's Wort has been well studied, so scientists know a lot about its safety and effectiveness. Others, like Cat's Claw, haven't.
In addition, botanical supplements can interact with medications, so if you take any medications, check with your healthcare provider. See our dietary supplement fact sheets for more information on the safety and effectiveness of specific botanical supplements. What does the term “standardized” on a product label mean? AT. Manufacturers of botanical supplements can identify and measure the specific chemical components of their products, often referred to as “markers”, and adjust them to ensure consistent batches.
However, the components responsible for the health effects of most botanicals are unknown. In addition, the term “standardized” has no legal or regulatory definition in the United States. Therefore, products labeled as “standardized” are not necessarily more effective, safer, or of higher quality than others. How can I find high-quality botanical supplements? AT.
Determining the quality of a botanical supplement can be difficult because the quality depends on the manufacturer and the production process. Your healthcare provider may be able to recommend a specific brand for you. A product label doesn't necessarily indicate quality, but you can search for quality assurance stamps from several independent organizations that offer quality testing. These stamps indicate that the product was manufactured correctly, contains the ingredients listed on the label and does not contain harmful levels of contaminants.
However, these seals do not guarantee that a product is safe or effective. I have a bad cold and have thought about trying echinacea. Since it's a natural herb, it should be safe, right? AT. Even though herbal products, such as echinacea, are natural, that doesn't mean they're always safe or good for you.
The safety of an herbal supplement depends on many factors, such as its chemical composition, how it works in the body, how it is prepared and how much it is taken. Many supplements contain active ingredients that can have strong effects on the body and can interact with certain prescription medications in ways that can cause problems. Always be alert to the possibility of unexpected side effects, especially when taking a new product. Echinacea doesn't usually cause serious side effects, although it sometimes causes nausea, stomach pain, diarrhea, or vomiting, and allergic reactions can occur.
Unfortunately, the results of echinacea studies are mixed, so it's not clear at this time if echinacea prevents or treats upper respiratory tract infections, such as the common cold. Do you have any more questions? See our fact sheet on botanical dietary supplements and a fact sheet on echinacea from the National Center for Complementary and Integrative Health. Valerian is an herb that is sold as a dietary supplement. It's found in some products touted as mild sedatives and sleeping pills, although it's not clear to what extent valerian is useful for these conditions.
Valerian, like all dietary supplements, should not be taken in place of or in combination with prescription medications without the approval of your healthcare provider. Like many herbs, scientists aren't sure which components in valerian are responsible for their effects. Dietary supplements are not required to be standardized in the United States, so valerian product formulations may vary. Therefore, it can be difficult to compare one valerian product to another and to determine the appropriate doses.
We recommend that you see your healthcare provider for advice. Do you have any more questions? See our fact sheet on valerian. I've been taking a prescription antidepressant, but I want to try something more natural. A friend told me about St.
John's Wort, but I've read that it can have side effects. How is that possible if it's from a plant? Do you have any more questions? See a fact sheet on St. John's Wort from the National Center for Complementary and Integrative Health. My doctor has told me to avoid dietary supplements, especially herbal products, because they haven't been tested to see if they're safe and effective.
Many people take them or want to try them, so why hasn't more research been done? AT. Dietary supplements are intended to supplement the diet; they are not intended to treat or prevent diseases. Unlike medications, dietary supplements don't have to undergo pre-marketing review or approval by the U.S. The Food and Drug Administration (FDA) is a measure that requires a great deal of research before they are available to the public.
However, many dietary supplements can have strong effects on the body, and we recognize that more research is needed on these products. That is one of the reasons why we have started programs such as the Consortium program to advance research on botanical and other natural products (CARBON) in partnership with the National Center for Complementary and Integrative Health. The CARBON program promotes collaborative and transdisciplinary research on the safety, efficacy and mechanisms of action of botanical dietary supplements and also supports the development of methods and resources that will improve the progress of this research. Do you have more questions about the CARBON program and our other research initiatives on dietary supplements? See our resource page for researchers.
I'm confused by all the different terms, such as ALA, EPA and DHA, that are used to refer to omega-3s from fish oil, flaxseed, or other sources. There are two main types of omega-3 fatty acids, “short chain” and “long chain”, so called because of their somewhat different chemical structures. ALA is one of the most common short-chain omega-3s, while EPA and DHA are the most common long-chain omega-3s. Plant foods such as linseed, soy and canola oils, as well as chia seeds and black walnuts, contain ALA.
Fish and other seafood, especially fatty cold-water fish, such as salmon, mackerel, and tuna, contain EPA and DHA. Most omega-3 supplements, including fish oil, krill oil, cod liver oil, and vegetarian products made with algae oil, contain EPA and DHA. Some foods, such as certain brands of eggs, yogurt, milk and soy beverages, contain added omega-3 fatty acids. You can check product labels to determine which.
Most research on the potential health benefits of omega-3s includes EPA and DHA. Our bodies can convert ALA into EPA and DHA, but not very well. So, if you want to increase the amount of EPA and DHA you consume, you should get them from food or dietary supplements. If you eat about 8 ounces per week of a variety of seafood, you are consuming approximately 250 mg of EPA and DHA each day.
A typical fish oil supplement provides about 300 mg of EPA and DHA, but doses vary widely. Do you have any more questions? See our fact sheet on omega-3 fatty acids. Are fish oil supplements recommended for cardiovascular disease? What does the latest research show? AT. Fish oil supplements help lower triglyceride levels, but their other effects on cardiovascular disease are less clear.
Studies done 10 or 20 years ago found that fish oil reduced the risk of some heart problems, such as sudden death and strokes, especially among people with heart disease. However, many recent studies have not found the same thing. Some researchers believe that changes in people's lifestyles, such as the increase in the use of statins and the increased consumption of fish in the last 10 to 20 years, could eclipse the potential benefits of fish oil. Research clearly shows that eating fish and other seafood as part of a healthy eating pattern reduces the risk of cardiovascular disease.
Therefore, experts recommend eating 8 ounces or more per week of fish and other seafood, including some varieties that have higher amounts of EPA and DHA (such as salmon, mackerel, and tuna). During pregnancy, experts recommend eating 8 to 12 ounces of a variety of seafood per week, choosing from varieties that are low in methylmercury. These include salmon, herring, sardines, clear tuna, and trout. Pregnant women should not eat certain types of fish, such as mackerel, shark, swordfish and white fish, that are high in methylmercury.
Some studies show that taking DHA or other omega-3 dietary supplements during pregnancy may slightly increase the baby's weight at birth and the time the baby is in the womb, which could be beneficial. However, it's not clear if taking these supplements during pregnancy affects the baby's health or development. My son plays soccer in high school and many of his teammates drink energy drinks. Are they safe for teens? AT.
The main thing to consider with energy drinks is the amount of caffeine they contain. Caffeine can cause nervousness, nervousness, and difficulty sleeping, and in very high doses, it can cause heart problems and can even be fatal. Do you have any more questions? See the section on caffeine in our fact sheet on dietary supplements for exercise and sports performance. I'm training for a marathon and I'm wondering if taking a creatine supplement would be useful.
Creatine is a compound that is stored in muscles and supplies them with energy. Your body produces some creatine, and it also gets some creatine from eating animal foods such as beef and salmon. Creatine supplements provide much larger amounts of creatine (usually in the form of creatine monohydrate) than you can get from your diet. Creatine supplements can increase strength, power, and the ability to contract muscles for maximum effort.
However, creatine is only useful for short, repeated periods of intense, intermittent activity, such as running and weight lifting. For endurance activities, such as running long distances, it seems to have little value. Creatine may cause weight gain because it tends to cause water retention, but is otherwise considered safe for healthy adults. Do you have any more questions? See the section on creatine in our fact sheet on dietary supplements for exercise and sports performance.
The other thing to consider is the quality of the protein. Protein is made of amino acids. The body produces some amino acids, but it needs to obtain others (known as essential amino acids, or EAAs) from food. Animal foods contain all the EAAs, but plant foods do not.
So, if you eat mostly or only plant foods, eat a variety of them to make sure you're consuming all the EAA. Most protein powders and beverages contain whey, a milk protein that provides all the EAAs. Do you have any more questions? See the section on proteins in our fact sheet on dietary supplements for exercise and sports performance. Here are some examples of interactions that can occur.
If you take medications and also plan to take dietary supplements, talk to your healthcare provider first and watch for any side effects or problems. We have a registry of dietary supplements and medications that you can use to keep track of dietary supplements and medications you take, so that you can share this information with your healthcare provider. Small changes in vitamin K intake from day to day are inevitable, but larger changes can cause problems. Vegetables, especially leafy greens, such as spinach, kale, turnip greens, collards and broccoli are particularly rich in vitamin K.
If you eat a spinach salad every day, it should be fine, but only if you eat it every day. Being so consistent can be difficult to achieve, which is why doctors sometimes recommend avoiding foods high in vitamin K to be safe. The same goes for any dietary supplement that contains vitamin K, including multivitamins. If you take one every day, that's no problem, but if you're inconsistent, it could cause problems.
Do you have more questions or want to see lists of foods that contain vitamin K? See our vitamin K fact sheet. My surgery is scheduled for a few weeks from now and my surgeon told me to stop taking my dietary supplements. Dietary supplements can cause problems during surgery. This can happen in a number of ways.
Some dietary supplements, such as garlic, ginkgo, and vitamin E, tend to thin the blood, which can increase the amount of blood that is bled during surgery. Some may react with anesthetics and others may affect blood pressure. All of this can cause unexpected problems during surgery. If you plan to have surgery, tell your surgeon and other healthcare providers about the dietary supplements you take and follow their instructions.
Do I need to take a dietary supplement during the COVID-19 pandemic? AT. Like many people, you may be wondering if you should take a dietary supplement to boost your immunity or improve your overall health in these unprecedented times. Some of you have asked us, for example, if we should take zinc or vitamin C, or if copper kills the COVID-19 virus. My child has ADHD and I want to avoid using medications.
Are there any dietary supplements that can help? AT. Many parents wonder if dietary supplements can help their children with attention deficit hyperactivity disorder (ADHD). Unfortunately, most supplements haven't been proven to help people with ADHD and some could be dangerous, so it's important to be careful. If you're considering natural therapies, such as dietary supplements, for your child, seek information from reliable sources and talk to your healthcare provider.
Vitamins and minerals are some of the most common supplements promoted for ADHD. If your child has a vitamin or mineral deficiency, your healthcare provider may recommend dietary changes or specific dietary supplements. But beyond that, taking extra vitamins and minerals won't necessarily help. And keep in mind that high doses of some vitamins and minerals can be harmful.
Scientists are studying other dietary supplements, such as fish oil, to see if they hold promise for ADHD. However, this research is still in its early stages, so we don't know if these products are effective. Do you have any more questions? See our fact sheets on dietary supplements and MedlinePlus information on ADHD. When did the new complementary information labels appear and how are they different from the old labels? Q.
Where can I buy dietary supplements? AT. Dietary supplements are available without a prescription at many retail outlets, such as grocery stores, pharmacies, general product retailers, health food stores, and specialty health and nutrition stores. Many dietary supplements can also be purchased online via the Internet. What brand (s) of dietary supplements should I buy? AT.
There are a number of factors, such as price, quality and availability, that can influence your purchase decision. The Office of Dietary Supplements (ODS) does not test, review, or rate dietary supplements, nor can we recommend certain brands. You may want to ask your healthcare provider for a recommendation. In addition, several independent organizations offer quality tests and allow products that pass these tests to display a quality assurance seal that indicates that the product was manufactured correctly, contains the ingredients listed on the label and does not contain harmful levels of contaminants.
These seals do not guarantee that a product is safe or effective. How can I know if the supplement I bought contains the ingredients that appear on the label or if it is contaminated? AT. You should keep in mind that the U.S. The Food and Drug Administration (FDA) does not test the content of dietary supplements.
However, the FDA has published good manufacturing practices (GMP) for dietary supplements, a set of requirements and expectations under which supplements must be manufactured, prepared and stored to ensure quality. Manufacturers are expected to guarantee the identity, purity, concentration and composition of their supplements. For example, GMPs aim to avoid the inclusion of wrong ingredients, the addition of too much or too little of a dietary ingredient, the possibility of contamination (by pesticides), heavy metals such as lead, bacteria, etc. Some manufacturers use the term standardized to describe efforts to make their products consistent.
Therefore, the use of this term does not guarantee the quality or consistency of the product. With so many dietary supplements to choose from, how can I compare the ingredients and doses of one product with those of another? AT. The Dietary Supplement Label Database (DSLD) contains information on the labels of thousands of dietary supplement products available in the U.S. It can be used to search, for example, for a specific ingredient in a product, a particular supplement manufacturer, the text of a label and a specific health-related statement.
Who is responsible for overseeing the regulation of dietary supplements in the United States? AT. In the United States, the. The Food and Drug Administration (FDA) has regulatory responsibility for dietary supplements. The FDA regulates dietary supplements according to a set of rules different from those related to conventional foods and medications (prescription and over-the-counter).
Under the Dietary Supplement Health and Education Act of 1994, the manufacturer of dietary supplements is responsible for ensuring that a dietary supplement is safe before it is marketed. The FDA is responsible for taking action against any unsafe dietary supplement once it hits the market. Manufacturers must ensure that the information on the product label is true and not misleading. The FDA's post-marketing responsibilities include monitoring safety, for example,.
Notification of adverse events on dietary supplements and product information, such as labeling, claims, package leaflets and accompanying literature. The Federal Trade Commission (FTC) regulates the advertising of dietary supplements in national or regional newspapers and magazines; in radio and television commercials, including infomercials; by direct mail to consumers; or on the Internet. The FTC requires that all information about supplements be truthful and not misleading. For more information, contact the FTC through its website.
How can I produce, market, import, distribute, or sell a dietary supplement in the United States? Q. Where can I find information or data on the sale and use of dietary supplements? AT. The ODS Population Studies Program evaluates the use of dietary supplements by the U.S. The population and specific population subgroups and the contributions of dietary supplements to nutritional status.
However, the Office of Dietary Supplements (ODS) does not track sales of dietary supplements. You can search for publications on this topic through scientific literature databases, including PubMed. In addition to searching for scientific publications, you can contact market research companies that provide sales and marketing data for the nutrition industry. Can I reproduce the fact sheets and other materials found on the Office of Dietary Supplements website? AT.
Most of the information available on the Office of Dietary Supplements (ODS) website is in the public domain and, unless otherwise stated, can be freely downloaded and reproduced, as long as the content has not been changed or modified. You can also link to individual pages within the ODS website, provided that the attribution is made to the ODS and any descriptive note accurately reflects the content of the page to which it is linked. Can I add a link to the Office of Dietary Supplements website from my website? You can also link to individual pages on this site, provided that it is attributed to the ODS and that any descriptive note accurately reflects the content of the page to which it is linked. How can I propose a link to my website from the Office of Dietary Supplements website? These criteria may change to reflect the new SDG web policies.
If your website meets the above criteria, you can propose a link to your website from the ODS website by contacting us. All submissions will be reviewed by ODS staff or external reviewers with experience in the subject. The linked sites are currently subject to regular review. You'll receive a decision by email in about 1 week.
To provide information from websites not sponsored or supported by the government to visitors to our website, ODS links to the MedlinePlus website of the National Library of Medicine. MedlinePlus provides good health information for health professionals and consumers from the National Institutes of Health and other reliable sources on more than 700 diseases and conditions. If your website provides reliable, science-based information about dietary supplements, we suggest that you contact MedlinePlus to request information on how to establish a link from their website. How do I know if the information I find on the Internet is reliable?.
Every day, thousands of people take dietary supplements. Experts from the Centers for Disease Control and Prevention (CDC) say that some of these supplements aren't as safe as you might think. A new CDC study published in The New England Journal of Medicine shows that nearly 23,000 people visit the Emergency Department (ED) each year because of dietary supplements. Many of these trips to the emergency room involve heart problems caused by weight-loss products and stimulants.
A key issue is that many over-the-counter dietary supplements aren't regulated by the Food and Drug Administration (FDA), so there's often no way to know if a supplement is safe or if it will cause adverse side effects. Donald Hensrud says: “The evidence supporting the beneficial health effects of most dietary supplements is not very strong and there are possible adverse effects.”. One of the reasons people take dietary supplements is to improve their overall health. However, the evidence supporting a healthy and balanced diet is much stronger than that of any dietary supplement.
You're the majority if you take vitamins and supplements regularly, but did you know that herbal or dietary supplements are on the rise? Most people take daily supplements in an attempt to stay healthy, increase energy before going to the gym, or even lose weight. However, research has determined that many of these supplements are causing liver damage. Dietary supplements are regulated by the FDA as foods, not as drugs. However, many dietary supplements contain ingredients that have strong biological effects that may conflict with a medication you are taking or with a medical condition you may have.
Products that contain hidden drugs are also sometimes falsely marketed as dietary supplements, putting consumers at even greater risk. For these reasons, it's important to consult with a health professional before using any dietary supplement. Read these consumer updates for more information. .
