Discuss all medical advice, diagnosis, and treatment with your healthcare provider.

The Basics

What is a dietary supplement?

According to the Dietary Supplement Health and Education Act, a dietary supplement is a product (other than tobacco) that is intended to be used in addition to foods in the diet and should not be taken as a replacement for food. Dietary supplements usually contain at least one or more dietary ingredients including vitamins, minerals, herbs, amino acids and enzymes. Depending on the kind of dietary supplement you take, it may be providing you with essential nutrients that may be lacking in your diet or it may be helping to promote optimal health. Dietary supplements are taken orally, as either pills, capsules, tablets, or liquids.

Nineteen percent of adult Americans are taking dietary supplements both with and without a healthcare professional's advice. People take dietary supplements for many different reasons including:

• Ensuring nutritional adequacy
• Protecting tissue structures and functions
• Treating the symptoms of disease
• Decreasing the risk of certain diseases and age-related changes
• Enhancing physical performance

The scientific evidence to support the benefit and the safety of any one dietary supplement varies. Some supplements are supported with good quality scientific studies that provide evidence of the benefit and risks. Other supplements are not well supported and have limited studies with conflicting evidence (meaning that the evidence from one scientific study differs from another). Solid evidence for the benefit of a supplement it doesn't necessarily mean that it comes without side effects. Therefore before considering using a supplement, always discuss any potential side effects with your healthcare provider.

Some top selling dietary supplements in the United States include:

1. Multivitamins
2. Vitamin C and E
3. Calcium
4. Iron
5. Glucosamine
6. Chondroitin
7. Probiotics
8. Fish oils
9. Coenzyme Q10
10. SAMe (S-adenosylmethionine)
11. Garlic
12. Ginkgo biloba
13. Cranberry
14. St John's wort

Dietary supplements are regulated by the US Foods and Drug Administration (FDA), but the regulation process is different for food and drugs. A product is classified as a food, a drug, or a dietary supplement depending on its intended use. The FDA is responsible for taking action against a dietary supplement if it is unsafe only after it reaches the market. In other words, the independent manufacturer of the dietary supplement can market an entity without the FDA's approval. It is the responsibility of the independent manufacturer to ensure the information on the label of the product is truthful and not misleading. Once the product is on the market, the FDA is responsible for monitoring safety.

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Who should take dietary supplements?

Dietary supplements are intended to supplement the diet and are not intended to be a replacement for food. Not everyone necessarily needs to take dietary supplements. People take them for various reasons and often without consulting a healthcare professional. Clinicians often recommend dietary supplements for certain individuals for a variety of reasons including an inadequate diet, an inability to improve one's diet, or a restricted diet.

For example:

• Vegetarians (especially those who don't eat animal products)
• People with food allergies
• People with malabsoprtion (where nutrients cannot be adequately absorbed in the intestines)
• People in hospital who may not be able to eat properly due to undergoing a surgical procedure
• Elderly people in residential care facilities who do not eat a well-balanced diet and who infrequently go outdoors

Common supplements taken because of an inadequate dietary intake include calcium, vitamin D, and iron.

Clinicians may recommend dietary supplements to prevent certain diseases, whereby scientific evidence suggests that dietary supplements may be beneficial and whereby the benefits outweigh the side effects.

For example:

• Probiotics
• Omega-3 fatty acids
• Fish oils
• CoQ10
• Ginkgo biloba
• Cranberry
• Folic acid
• SAMe (S-adenosylmethionine)
• Glucosamine
• Chondroitin
• Calcium

Always talk to your doctor, pharmacist, or nurse before you take any dietary supplement, as these products may have risks. They could be harmful to your health if:

• You are taking other dietary supplements (it may result in a deleterious interaction)
• You are taking other prescription or over-the-counter medicines (it may result in a drug interaction)
• You use them instead of medicine that your doctor prescribes

It is also possible to take too much of certain nutrients, and this could lead to adverse consequences. For example, a pregnant woman who takes too much vitamin A may cause birth defects in her unborn child. Always be sure to talk to a healthcare provider before adding supplements to your diet.

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Dietary supplements and women: the statistics

• Americans spend over $13 billion on dietary supplements ranging from vitamins to herbal products like ginkgo biloba, kava kava, and St. John's wort.  
• A recent survey of interviewees showed that 49% had used a supplement within the past year, and 24% used them regularly.
• By sales, the two leading categories of supplements are "general health" and "sports/energy/weight-loss" with $4.4 billion and $4.7 billion, respectively.
• The United States leads the world in dietary supplement usage with 100.4 million Americans using vitamin and minerals every day and 37.2 million using herbal remedies regularly.

Common dietary supplements

Several dietary supplements can be useful in the prevention or treatment of common conditions, but there are often different ways of preventing and treating medical conditions. The important issue to realize is that when there is scientific data to support the usefulness of a therapy it often means that there is knowledge about what to expect with that therapy both in terms of positive and negative effects. Remember that with the Dietary Supplement Health and Education Act of 1994, manufacturers do not need to provide the US FDA with proof of the safety and effect of their product before marketing it.

Before using any of these supplements you should discuss your condition with your healthcare provider because he or she may suggest other therapies more suitable for you. Here are some common dietary supplements that people use. In addition, we will describe their uses and the scientific data behind them.

1. Calcium

There is scientific data to support that calcium supplementation is useful for reducing bone loss in postmenopausal women, and therefore can help towards preventing osteoporosis.

There is also scientific data to support that calcium supplementation of 1200 mg to 1600 mg per day is useful as a treatment option for premenstrual symptoms.

2. Iron

People who do not get enough iron in their diets will show low iron levels on their lab tests. The lab test for iron is called iron studies. Vegetarians, for example, will often have abnormal iron studies. Iron deficiency is the most common nutritional deficiency worldwide and iron supplementation is often the treatment of choice. There is scientific evidence to suggest that taking vitamin C together with iron supplements is important to ensure that iron is absorbed in the gut.

3. Vitamin D

Natural forms of vitamin D are found in animal-based food products and in the skin as a result of sun exposure. Studies show that elderly people with medical conditions who cannot properly absorb fat into their gut and vegans may have deficiency in vitamin D, which is required for strong bones (for example, Crohn's disease, cyctic fibrosis, and liver disease).

Your healthcare professional can do lab tests to diagnose vitamin D deficiency. Therapy with vitamin D supplements is important if blood levels are low.

4. Glucosamine/Chondroitin

Glucosamine/Chondroitin is actually the third top selling nutritional product. Glucosamine is made from shellfish and those allergic to shellfish should avoid using it. Chondroitin is made from animal cartilage (mainly shark and cow).

There is scientific evidence to suggest that glucosamine is useful in improving symptoms in osteoarthritis as well as helping to prevent the joint from deteriorating further.

For the relief of pain in osteoarthritis there are other therapies that may be useful also such as acetaminophen and anti-inflammatory medications. Therefore, it is always important to discuss with your healthcare professional the right treatment for you.

5. Probiotics

Probiotics are live organisms that may effect human health by altering the bacterial colonies in the intestines. There are different strains of probiotics and some strains have scientific data to support their benefit. Lactobacillus rhamnosus and Saccharomyces boulardii for example reduce the risk of diarrhea associated with the use of antibiotics. Some strains may be beneficial for irritable bowel syndrome and vaginal yeast infections.

6. Omega-3

Omega-3 fatty acids can be found in fish or fish oil supplements. There is scientific data to suggest that omega-3 fatty acids reduce triglycerides in the blood and, to some extent, can also alter in some people the deleterious outcomes of cardiovascular disease. Recommended dose of omega-3 fatty acids is 1 g to 1.5 g per day.

7. Coenzyme Q10

There is evidence to suggest that supplementation with coenzyme Q10 may benefit cholesterol levels in people over the age of 65 and it may also be beneficial in people with cardiovascular diseaseheart failure.

8. SAMe (S-adenosylmethionine)

There is evidence to suggest that supplementation with SAMe can help in the treatment of depression, although people with bipolar disorder should not take it. If you are feeling depressed or have been diagnosed with depression you should discuss your treatment with your healthcare professional as he or she will know all the treatment options that exist for you.

9. Ginkgo Biloba

There is evidence to suggest that ginkgo can improve symptoms of early dementia. However, other evidence suggest that ginkgo may cause bleeding and, therefore, you should discuss your condition with your healthcare professional before using it.

10. Cranberry

There is scientific evidence to suggest that cranberry reduces the number of urinary tract infections in some women. Cranberry can be taken in capsule form or as cranberry juice.

The following commonly used dietary supplements have conflicting reports of their benefit:

11. Garlic

Garlic may have slight benefit in reducing cholesterol, but the scientific data varies and are conflicting. Large doses of garlic can interact with medication that thins the blood, such as coumadin.

12. St. John's wort

St. John's wort has been used by some people for the treatment of depression. However, there is no consistent scientific data to back up its benefit. If you suffer from depression you should always see your healthcare professional for advice because depression is a serious and complicated illness that requires an individualized treatment plan.

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Which dietary supplements in particular affect women?

Menstruation
If you have exceptionally heavy periods, you may develop iron deficiency and need iron supplementation.

Pregnancy
During pregnancy, calcium, folate, and iron are nutrients in high demand. Folate is important early in pregnancy to protect your developing baby from birth defects like spina bifida (incomplete closure of the spine). Iron is found in red blood cells that help deliver oxygen to you and your baby. Calcium helps to keep your bones strong.

Menopause
After menopause, women experience a sudden decline in estrogen levels, which hastens bone loss. To help prevent bone loss, you need to supplement your diet with vitamin D and calcium.

Weight Loss
Diet pills are some of the most common dietary supplements, and they are often the most misused. Women will often jump on the new fad pill in hopes that they can loose weight easily and fast. Some woman are searching for a miracle cure or "magic pill" in order to loose weight.

Here are some other reasons why overweight woman may choose to use dietrary supplements for weight loss:

• Being overweight has a social stigma
• Being a normal weight is healthy and benefical to the heart
• They want a "magic cure" for weight loss
• Diet pills seem an easier option than exercise and diet
• They have failed to loose weight despite trying over and over again
• Dietary supplements can be purchased over the counter
• A false sense of trust: thinking that dietary supplements must have no side effects and are natural
• False advertising

Usually the most effective and safest way to lose weight is to eat a balanced diet and to exercise. You should talk to your healthcare professional if you are thinking of loosing weight. He or she will advise you on what is the best weight loss plan for you, and may also advise you to see a dietitian for further advice.

Here are some facts about diet pills currently on the market. For the following products there is evidence that either they lack quality, safety, or a beneficial effect and therefore are not recommended. For example, use of products that contain ephedra should be actively discouraged because of serious safety concerns. Chitosan appears to be ineffective for weight loss and should also be discouraged. The use of guar gum for weight loss should be discouraged because of its lack of beneficial effect.

Dietary or herbal supplement	Claims	What you should know
Bitter orange	Increases number of calories you burn	Has emerged as a substitute for ephedra, but may cause similar health problems to ephedra
Chitosan	Blocks the absorption of dietary fat	Relatively safe, but unlikely to help with weight loss Can cause constipation and bloating
Chromium	Alters metabolism or carbohydratess and fats	Relatively safe, but unlikely to cause weight loss
Conjugated linoleic acid (CLA)	Reduces body fat	Can cause gastrointestinal problems
Country mallow (heartleaf)	Increases number of calories you burn	Contains ephedra, which is dangerous
Ephedra	Decreases appetite	Can cause high blood pressure, heart rate irregularities, sleeplessness, seizures, heart attacks, strokes, and even death Banned from marketplace for safety concerns, but still sold legally as tea
Green tea extract	Increases fat metabolism	Limited evidence to support this claim May cause indigestion, vomiting, and diarrhea
Guar gum	Increases the feeling of fullness, leading to decreased calorie intake	Relatively safe, but unlikely to cause weight loss

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Ask your Healthcare Provider

Talking to your healthcare provider

Dietary supplements are products intended to be profitable. While there are plenty of reputable supplements that can be beneficial to your health, it's important to be wary. Talk to your healthcare professional before taking new dietary supplements. To help you inform him or her of important points, be prepared to share the following information:

• Are you currently taking a dietary supplement?
• If so, what kind?
• What is your purpose for taking a dietary supplement?
• Are you taking any other medications?
• Do you eat fewer than two meals per day?
• Is your diet restricted? (Are you a vegetarian? Do you eat dairy?)
• Do you have more than three alcoholic drinks per day?

It's also good to keep a dietary supplement diary. You can share this with your healthcare provider to ensure that you are not taking anything conflicting or that might cause complications. When completing your dietary supplement diary, make sure to take into account your supplements as well as any fortified foods that you consume. For example, if you have orange juice fortified with vitamin D, make a note of that in your diary as well. Here is an example of a dietary supplement diary:

Supplement	Amount	How often	Reason
Multivitamin-mineral	One tablet	Once a day	Supplement diet
Vitamin-D fortified orange juice	8 oz	Once a day	Promote healthy bones

Ask your healthcare provider the following questions:

• Is taking a dietary supplement important to my total diet?
• Are there any precautions or warnings I should know about?
• Are there any known side effects?
• If I am scheduled for surgery, should I discontinue use of dietary supplements?
• If I am pregnant, will dietary supplements affect my unborn child?

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How do dietary supplements interact with drugs?

One of the reasons it is so important to talk to your clinician before self-medicating with dietary supplements is that there are some serious reactions between certain supplements and medications. Your healthcare professional knows your medical history and can give you the best advice.

For example, St. John's wort may interact with selective serotonin reuptake inhibitor (SSRI) drugs (that is, antidepressant drugs and birth control pills), digoxin, cyclosporine, and oral contraceptives. And large doses of garlic can interact with blood thinners, for example, coumadin.

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Frequently asked questions

What are the best foods to eat in order to get enough calcium in my diet?

This is how much calcium you should be getting:

Female Age	Calcium (mg/day)	Pregnancy & breast feeding
0 - 6 months	210	N/A
7 - 12 months	270	N/A
1 - 3 years	500	N/A
4 - 8 years	800	N/A
9 - 13 years	1300	N/A
14 - 18 years	1300	1300
19 - 50 years	1000	1000
51+ years	1200	N/A

*mg = milligrams

Foods with calcium

Food	Calcium, milligrams
Milk (skim, 2%, or whole, 8 oz)	300
Yogurt (6 oz)	370
Orange juice (with calcium, 8 oz)	300
Tofu with calcium (1/2 cup)	435
Cheese (1 oz)	195-335 (hard cheese = higher calcium)
Cottage cheese (1 cup)	130
Ice cream or frozen yogurt (1/2 cup)	100
Soy milk (1 cup)	100
Beans (1/2 cup cooked)	60-80
Dark, leafy green vegetables (1/2 cup cooked)	50-135
Almonds (24 whole)	70
Orange (1 medium)	60

How can I get more information about a particular dietary supplement such as whether it is safe and effective?
Scientific evidence supporting the benefits of some dietary supplements (for example, vitamins and minerals) is well established for certain health conditions, but other supplements need further study. This is partly due to the way dietary supplements are regulated by the US Food and Drug Administration (FDA).

Research studies to prove that a dietary supplement is safe for people are not required before the supplement is marketed, unlike for drugs. It is the responsibility of dietary supplement manufacturers/distributors to ensure that their products are safe and that their label claims are accurate and truthful. If the FDA finds a supplement to be unsafe once it is on the market, only then can it take action against the manufacturer and/or distributor, such as by issuing a warning or requiring the product to be removed from the marketplace.

The manufacturer does not have to prove that the supplement is effective, unlike for drugs. The manufacturer can say that the product addresses a nutrient deficiency, supports health, or reduces the risk of developing a health problem, if that is true. If the manufacturer does make a claim, it must be followed by the 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."

In some cases, dietary supplements may have unwanted effects, especially if taken before surgery or with other dietary supplements or medicines, or if you have certain health conditions. Be advised that supplements should not replace prescribed medications or the variety of foods important to a healthful diet.

Do not self diagnose any health condition. Work with your healthcare provider to determine how best to achieve optimal health and always check with your clinician before taking a supplement, especially when combining or substituting them with other foods or medicine.

Where can I find information about the use of dietary supplements for a particular health condition or disease?
One of the best places to start is to talk to your healthcare professional. You can also find information on the Internet, though it is essential to make sure it is a reliable source. Here are some reliable sources of information on dietary supplements:

• Health Information from the National Library of Medicine's MedlinePlus Database: http://www.nlm.nih.gov/medlineplus/
• Fact sheets on dietary supplements from the National Institutes of Health: http://dietary-supplements.info.nih.gov/Health_Information/ Information_About_Individual_Dietary_Supplements.aspx
• IBIDS database of dietary supplement literature: http://dietary-supplements.info.nih.gov/Health_Information/IBIDS.aspx

Where can I report a complaint about a particular dietary supplement?
To report an illness or injury associated with a dietary supplement, please talk with your healthcare provider and contact the US FDA. To report a complaint involving misleading advertising, fraud, or other consumer protection matter associated with a dietary supplement, please contact the Federal Trade Commission: https://rn.ftc.gov/pls/dod/wsolcq$.startup?Z_ORG_CODE=PU01

Where can I purchase dietary supplements?
Dietary supplements are available without a prescription through a number of retail outlets including grocery stores, drug stores, general merchandise retailers, natural food stores, and specialty health and nutrition stores. Many dietary supplements can also be purchased online through the Internet.

Which brand(s) of dietary supplements should I purchase?
There are a number of factors including price, quality, and availability that may influence your buying decision. The Office of Dietary Supplements (ODS) does not test, analyze, or rate dietary supplements, nor can we recommend certain brands. You may wish to ask your healthcare provider to make a recommendation.

If you have questions about a specific brand of dietary supplements, you can contact the manufacturer for more information. Ask to speak to someone who can address your questions, some of which may include:

• What information does the firm have to substantiate the claims made for the product? Be aware that sometimes firms supply so-called "proof" of their claims by citing undocumented reports from satisfied consumers, or graphs and charts that could be mistaken for well conducted scientific research.
• Does the firm have information to share about tests it has conducted on the safety or efficacy of the ingredients in the product?
• Does the firm follow good manufacturing practices and have a quality control system in place to determine if the product actually contains what is stated on the label and is free of contaminants?
• Has the firm received any adverse events reports from consumers using their products?

In addition, there are a few independent organizations that offer "seals of approval" that may be displayed on certain dietary supplement products. These indicate that the product has passed the organization's quality tests for things such as potency and contaminants. These seals of approval do not mean that the product is safe or effective; they provide assurance that the product was properly manufactured, that it contains the ingredients listed on the label and that it does not contain harmful levels of contaminants.


How do I know if the supplement that I purchased contains the ingredients that it claims on the label or if it is contaminated?
You should be aware that the US FDA does not analyze the content of dietary supplements. At this time, supplement manufacturers must meet the requirements of the FDA's Good Manufacturing Practices (GMPs) for foods. GMPs describe conditions under which products must be prepared, packed, and stored. Food GMPs do not always cover all issues of supplement quality. Some manufacturers voluntarily follow the FDA's GMPs for drugs, which are stricter.

Some manufacturers use the term "standardized" to describe efforts to make their products consistent. However, US law does not define standardization. Therefore, the use of this term (or similar terms such as "verified" or "certified") does not guarantee product quality or consistency.

Who is responsible for overseeing the regulation of dietary supplements in the United States?
The FDA has regulatory responsibility for dietary supplements. The FDA regulates dietary supplements under a different set of regulations than those covering conventional foods and drug products (prescription and over-the-counter). Under the Dietary Supplement Health and Education Act of 1994, the dietary supplement manufacturer 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 product after it reaches the market.

Manufacturers must make sure that product label information is truthful and not misleading. The FDA's postmarketing responsibilities include monitoring safety, for example, voluntary dietary supplement adverse event reporting, and product information, such as labeling, claims, package inserts, and accompanying literature.

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Empower Yourself

What to know about dietary supplements

Chances are, if you're thinking about using dietary supplements, you are concerned about your health. Just remember that these products do not have to be approved by the FDA to be on the market. That means that it is up to you to know what you are putting in your body. Don't believe the advertisements—do your research! Remember that natural doesn't always mean safe—there can be toxicity in naturally-occurring substances. Follow these guidelines to make sure you don't put anything harmful in your body:

• Do not substitute a dietary supplement for a prescription medicine or therapy.
• Don't chase the latest dietary fad. Real health advice is generally based on many research studies over time, not a single study touted by the media. Be wary of results claiming a "quick fix" that depart from scientific research and established dietary guidance.
• Remember: "If something sounds too good to be true, it probably is." Some examples of false claims on product labels:
  • Quick and effective "cure-all."
  • Can treat or cure disease.
  • "Totally safe," "all natural," and has "definitely no side effects."
  • Limited availability, "no-risk, money-back guarantees," or requires advance payment.
• More may not be better. Some products can be harmful when consumed in high dosages, for a long time. Don't spend a lot of money on a product because you feel pressured by a salesperson. Some supplement products can be very expensive and may not provide the benefit you expect. For example, excessive amounts of water-soluble vitamins, like C and B vitamins, are not used by the body and are eliminated in the urine.
• Always talk to your healthcare provider if you are concerned about your health and if you are thinking of using a dietary supplement.

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Glossary of dietary supplement terms

Absorption: The digestibility of a dietary supplement into the bloodstream (similar to bioavailability).

Adequate intake (AI): A dosage recommendation that may be used on a product label where RDA information is lacking and that is labeled as DV's.

Adverse event report (AER): A report of an incident where it is believed that a substance may have caused a health problem or detrimental event.

Amino acid: Molecules that are the building blocks of proteins. The body requires amino acids to sustain life, some of which the body can make and others it cannot, therefore it needs to come from food. These are called essential amino acids.

Assay: The analysis of a substance or mixture to determine its constituents and the relative proportion of each.

Bioavailability: The rate and extent to which a drug or dietary supplement is absorbed into general circulation, thereby permitting access to the site of action. Measured by the concentration in body fluids, usually blood, or by the magnitude of the pharmacological response. Expressed as a fraction of an administered dose.

Biological assay: Estimation of strength of a drug or substance by comparing its effects in test animals to a reference standard.

Biological marker compound: A compound for which a product is tested to determine if a particular plant material is present. Used for quality control.

Bipolar disorder: A psychiatric condition characterized by recurrent episodes of mood disturbance fluctuating between depression and mania.

Botanicalsz: Products made from plants, including herbs.

Cardiovascular disease: Disease of the heart and circulatory system, meaning the arteries and veins.

Celiac disease: A chronic gastrointestinal disease caused by intolerance to gluten. The intolerance means that gluten consumption leads to damage of the wall in the small intestine, which results in malabsorption of nutrients.

Certificate of authenticity: Documentation that accompanies raw materials used to manufacture dietary supplements that attests to their authenticity.

Chondroitin: An important ingredient in cartilage and is found often in combination with glucosamine in dietary supplements.

Clinical trial: Research studies that use human beings (rather than animals). Clinical trials are conducted in healthcare settings with voluntary patient-participants.

Coenzyme Q10: A substance present in all human cells that has antioxidant properties meaning that it can protect human cells from the detrimental effects of free radicals. It is found in dietary supplements.

Control group: The group of patients in a clinical trial who receive either the current standard care or a placebo. Results of the control group are compared with results of the treatment group. No patient is placed in a control group without treatment if any beneficial treatment is known.

Crohn's disease: A chronic gastrointestinal condition where there is inflammation in the wall of the intestines leading to pain, diarrhea, and other symptoms. The cause is not known and there is no cure. As a result of intestinal inflammation people with this condition experience malabsorption and are at risk of nutritional deficiencies.

Cystic fibrosis: A genetic disease of the lungs and gastrointestinal system. Some of the most troublesome complications in cystic fibrosis are shortness of breath, recurrent chest infections, malabsorption, and much-reduced life expectancy.

Dementia: A progressive brain disease resulting in a gradual decline of cognitive function that effects certain areas such as memory, attention, writing, speech and problem solving.

Dietary reference intakes (DRIs): An umbrella term for groups of values (including RDAs, AIs, EARs, and UIs) that specify recommended dosages. Proposed by the Food and Nutrition Board of the Institute of Medicine of the National Academy of Sciences in partnership with Health Canada.

Dietary supplement: The term "dietary supplement" has a specific legal meaning in the US established by DSHEA. It refers to a product that supplements the diet and whose label clearly states that it is a dietary supplement. It is distinct from a drug which is represented as a substance that is intended to diagnose, cure, mitigate, treat, or prevent diseases and which must undergo extensive testing and be preapproved by the FDA before being sold. There are specific cases where dietary supplements may also be labeled as impacting disease.

Dietary supplements may contain the following kinds of ingredients: vitamins, minerals, herbs, botanicals, other plant-derived substances, amino acids (the individual building blocks of protein) and concentrates, metabolites, constituents, and extracts of these substances. They are intended for ingestion in pill, capsule, tablet, or liquid form and are not represented for use as a conventional food or as the sole item of a meal or diet.

Disease: The term disease commonly refers to any deviation from the normal structure or function of the human body that is manifested by a characteristic set of one or more signs or symptoms. The FDA is no longer proposing to broaden the definition of disease to include such conditions as pregnancy, menopause, and aging.

Disintegration: The drop in potency of a dietary supplement while in storage as a function of time and storage conditions (light, heat, moisture, and air). Stable supplements have a low rate of disintegration allowing for a later expiration date, while others lose potency comparatively quickly.

Dissolution: The portion of an ingredient, usually expressed as a percentage, that dissolves in the human digestive tract — thereby making it available for absorption in the body. The combined effect of dissolution and absorption determines how much of a consumed ingredient ends up in the bloodstream.

Double blind research: A clinical trial in which neither the researchers nor the patients know who is receiving the treatment being tested and who is in the control group. Blinding a study prevents personal reactions and bias from influencing the study results. If necessary, treatment received by any specific individual can be quickly identified by a special code. (See also single blind research.)

Drugs: In the United States, medicinal products used for the treatment of diseases.

DSHEA: The Dietary Supplement Health and Education Act passed in the United States in 1994. DSHEA served to deregulate the labeling of dietary supplements by giving manufacturers freedom to market more products as dietary supplements and to provide specified kinds of information about their products' benefits.

DV "Daily value": New dietary supplement regulations went into effect in March of 1999 that require labeling of dietary reference intakes (DRI) and which appear as "DV" on product labels.

Efficacy: A synonym for effectiveness. Effectiveness (in the context of dietary supplements): The likelihood of benefit from use of a product when taken according to published or labeled guidelines.

Enzyme: A protein that acts as a catalyst in a chemical reaction. The body is full of naturally occurring enzymes.

Estimated average requirement (EAR): The intake value that is estimated to be optimal for about half of the individuals in a specified group. In other words, the EAR meets a specified requirement in 50% of an age- and gender-specific group. At this level of intake, the remaining 50% of the specified group would not have its needs met. EAR is one of the guidelines encompassed in DRI (dietary reference intakes) established by the National Academy of Sciences.

Excipient: An inert substance used as a medium in pills and capsules that forms a vehicle for delivery of a drug or dietary supplement.

Extract: A solution obtained by soaking a plant in solvent, then allowing it to evaporate.

Extramural research: Studies conducted by outside organizations.

Folate (folic acid): Water soluble form of vitamin B9 found in vegetables such as spinach, dried beans and peas, fortified cereals, sunflower seeds, and certain other fruits and vegetables.

Food additive: Substance added to food to increase its flavor, storage characteristics, color, aroma, nutritional content, or other qualities.

Functional foods: Generally refers to a broad category of food that is formulated for (and promoted as having) special health benefits.

Genetically modified organisms (GMOs): Foods that have been created or modified by the use of genetic engineering techniques in which DNA has been introduced, deleted, or inhibited.

Ginkgo biloba: A tree with leaves that contains extracts used in different supplements and pharmaceuticals.

Glucosamine: A substance found in the shells of crustaceans and commonly used as a treatment (although not FDA approved) for people with osteoarthritis.

Good Manufacturing Practices (GMPs): Procedures for manufacturing dietary supplements that are used to ensure a consistent level of quality. GMPs embody procedures that ensure purity, cleanliness, freshness, and proper labeling.

GRAS (generally recognized as safe):  a category of food additives designated by the US Food and Drug Administration.

Hazard analysis critical control points (HACCP): Protocol adopted by Codex for controlling outbreaks of contaminated foods. The USDA and FDA are working to integrate Codex guidelines into US regulations. This could affect dietary supplements for specific cases where food bacteria or other extreme conditions infiltrate a supply.

Health claim: A claim that a dietary supplement or drug can be used to prevent or treat abnormalities or disease.

Heart failure: A disorder of the heart where for various reasons the heart has a reduced capacity for filling with blood and/or a reduced ability to pump blood to the rest of the body.

Herbs: A supplement derived from a seed-producing plant that does not develop persistent woody tissue but dies down at the end of a growing season.

Homeopathy, homeopathic remedies: The term homeopathy comes from the Greek homoios (meaning "similar") and pathos (meaning "suffering"). Homeopathic remedies are usually dilutions of natural substances from plants, minerals, and animals. These remedies act to stimulate the body's natural healing responses to specific symptoms. Homeopathy was founded by Dr. Samuel Hahnemann in the late 18th century.

In vitro research: Studies that use biological substances.

Interaction: Side effect resulting from concurrent use of multiple drugs or dietary supplements. The result may be antagonism (counteracting) or synergism (amplifying) and consequently may be adverse in some cases.

Irritable bowel syndrome: An intestinal disorder characterized by abdominal pain and changes in bowel habits (either constipation, diarrhea or a combination of both).

LOAEL (lowest observed adverse effect levels): The lowest intake at which some adverse effects have occurred under certain circumstances; the lowest dosage of a particular dietary supplement at which an adverse effect was reported.

Malabsorption: A condition where due to various disorders there is a problem with the absorption of certain nutrients in the intestine and usually results in symptoms of diarrhea and problems meeting adequate nutritional requirements.

Metabolism (assimilation): Physical and chemical changes that take place within an organism; all energy and material transformations that occur within living cells. Includes growth as well as energy changes: all transformations of chemical energy of foodstuffs to mechanical energy or heat. Includes anabolism (the conversion of ingested substances into the constituents of protoplasm), and catabolism (the breakdown of substances into simpler substances, the end products usually being excreted).

Metabolite: A substance essential to the metabolism of a particular metabolic process.

Mineral: A chemical substance formed through natural means on Earth.

Monograph: A published research report about a dietary supplement or class of dietary supplement that includes information regarding category, pharmacology, precautions, side effects, patient consultation, and general dosing information.

Multivitamins: A dietary supplement that contains more than one type of vitamin or mineral.

Natural foods: Usually identified as foods or foods containing products that are either unprocessed or organically grown.

Naturopathy, naturopath, naturopathic physician: Naturopathic medicine focuses on the body's innate ability to heal. Naturopathic physicians provide complete diagnostic and therapeutic services and are licensed or accredited, depending on where they received their degree and in which state they practice. They consider a patient's diet, lifestyle, work, and personal history when designing treatment—which may include nutrition, herbs, homeopathy, acupuncture, hydrotherapy, massage, and counseling as well as more conventional therapies.

NOAEL (no observed adverse effect levels): Intake level of a dietary supplement at which there are no credibly-substantiated adverse reactions observed in humans.

Nutraceutical: A legal definition that, according to the Dietary Supplement Health and Education Act (DSHEA), is any nontoxic food extract supplement that has scientifically proven health benefits for disease treatment or prevention. DSHEA requires that this food component be standardized in the nutraceutical product and manufactured under good manufacturing practices (GMPs). Nutraceuticals are not whole foods, yet are partially or completely derived from them. There are four types of nutraceuticals:

• Vitamins, minerals, and other dietary supplements in the form of pills or capsules
• Products based on extracts from foods or beverages in normal use (such as garlic, broccoli, red wine)
• Food extracts claiming a medical benefit (such as oat bran lowering cholesterol, aloe vera juice healing ulcers)
• Natural substances that people might not usually eat but that may prevent or treat illness (such as colloidal silver, hypericin, ginsenosides)

Nutrient: Food or substance that supplies the body with elements necessary for metabolism.

Nutrition: All the processes involved in taking in and utilizing food substances whereby growth, repair, and maintenance of activities in the body as a whole or in any of its parts are accomplished; includes ingestion, digestion, absorption, and metabolism.

Omega-3 fatty acids: A polyunsaturated fatty acid found in some foods, like fish, that is useful in preventing cardiovascular disease.

Organic foods: A labeling term for products produced under the authority of the Organic Foods Production Act, which regulates allowable soil conditions and restricts the use of irradiation, genetically-engineered organisms, pesticides, fertilizers, and additives in the production of foods. From the Organic Trade Association.

Osteoathritis: A condition in the joints where the cartilage wears down and results in joint inflammation, pain, swelling, and joint deformity.

Osteoporosis: A condition characterized by reduced bone strength and an increased risk of developing fractures.

Over-the-counter drugs: In the United States, drugs that do not require a prescription.

Overage: Excess potency that is manufactured into a dietary supplement to allow for disintegration so that the product maintains the potency level of its labeled unit amounts through the expiration date.

Peer review: Analysis of research by a group of professionals of comparable knowledge and expertise in a specific scientific or medical field.

Pharmacology: The study of drugs and dietary supplements and their origin, nature, properties, and effects upon living organisms.

Pharmacopoeia: Authorized treatise on drugs or dietary supplement and their preparation, especially a book containing formulas and information that provides a standard for preparation and dispensation.

Phytochemical: Relating to the chemistry of plants, plant products, and plant processes.

Phytomedicinals: Medicines derived from plants.

Placebo: An inactive substance with no medicinal effects that sometimes is used in research control groups.

Postmenopausal: The period of time after a woman has gone through her menopause.

Premenstrual: The period of time before a woman's menstruation begins.

Probiotics: Dietary supplements that contain bacteria or yeast that may be beneficial to human health.

Protocol: A treatment plan or outline. In clinical trials, a protocol is the plan for using an experimental procedure or treatment.

Random off-the-shelf testing: Testing of one or more products performed by an independent laboratory to measure quality. Products are picked randomly from a retail store shelf in accordance with a procedure that ensures random and unbiased selection.

Randomized controlled trial: A research study that uses two or more groups of research subjects. The treatment group receives the experimental treatment while the control group receives either a placebo or current standard treatment. (If the research is also a clinical trial, these research subjects are people.)

Recommended Dietary Allowance (RDA): Dietary intake goals for healthy people in 16 different age and gender groups based on a consensus of the Food and Nutrition Board of the Institute of Medicine of the National Academy of Sciences. RDAs serve as the basis for the US Recommended Daily Allowances, the Food and Drug Administration's standards for required nutrition labeling of foods.

Recommended Daily Allowance (US RDA): Dietary intake goals established by the U.S. Food and Drug Administration and based on the highest RDA values in a gender/age group. US RDAs are more widely used than RDAs.

Research: Many varieties and categories of research are relevant to dietary supplements. See clinical trial, control group, double-blind study, in vitro research, peer review, placebo, randomized controlled trial, single-blind study, treatment group.

S-adenosylmethionine (SAMe): A dietary supplement that may have potential benefit in the treatment of depression.

Safety: A safe dietary supplement is one that does no harm when used under defined conditions and as intended. An unsafe substance may result from toxicity, drug interactions, contraindications, allergies, or contamination.

Scientific evidence (scientific data): Evidence which supports a particular hypothesis or theory that has been validated through a valid scientific or clinical research study or trial.

Selenium: A naturally occurring chemical element that is also an essential human nutrient.

Shelf-life: The period of time during which a dietary supplement remains sufficiently potent to be effective. The expiration date on a product label should indicate the end of this time period.

Single-blind research: Clinical trials in which the patients do not know which treatment they are receiving—but the researcher does.

Soy milk: A drink made from soy beans.

Spina bifida: A birth defect where there is abnormal brain and/or spinal cord development as a result of defective and incomplete closure of the embryonic neural tube (the neural tube is the origin of the central nervous system).

Standard operating procedures: Internal procedures for manufacturing and quality control of dietary supplements.

St. John's wort (Hypericum perforatum): A plant that is found in dietary supplements and said to have a potential benefit in reducing symptoms of depression and anxiety.

Structure/function claims: Claims that a dietary supplement benefits by maintaining healthy or normal structures or functions of the human body—as opposed to preventing or treating abnormalities (health claims).

Tofu: A food made from curdling soy milk.

Tolerable upper intake level: The maximum level of daily nutrient intake that is unlikely to pose risks of adverse health effects to almost all of the individuals in the group for whom it is designed. UI is one of the guidelines encompassed in DRI (dietary reference intakes) established by the National Academy of Sciences.

Toxicity: The extent, quality, or degree to which a substance is poisonous; in other words, the degree to which it interferes with normal physiological functions. Because almost any substance can be poisonous if consumed in sufficient quantity, toxicity generally refers to intake of excessive dosages.

Treatment group: The group of patients who receive the new treatment in a clinical trial. Results of the treatment group are compared with results of the control group. Researchers can then judge whether the new treatment is as good as or better than current standard care.

Urinary tract infection: A bacterial infection of the kidneys, ureters, bladder, and urethra

Vegan: Excluding the consumption of any animal products.

Vitamin: Chemical compounds that are required by the body for certain chemical reactions.

Zinc: An essential metal element, necessary to sustain life.

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Resources and tools

Government Agencies

*Accepts Spanish calls

*Office of Dietary Supplements
National Institutes of Health
Suite 3B01
6100 Executive Boulevard
Bethesda, MD 20892-7517
Phone: 301-435-2920
Fax: 301-480-1845
http://ods.od.nih.gov

*National Women's Health Information Center, OWH, HHS
8270 Willow Oaks Corporate Drive
Fairfax, VA 22031
Phone: (800) 994-9662
TDD: (888) 220-5446
Fax: (703) 663-6942
http://www.4woman.gov/faq/depress.htm#e

*National Center for Complementary and Alternative Medicine, NIH, HHS
PO Box 7923
Gaithersburg, MD 20898
Phone: (888) 644-6226
TTY: (866) 464-3615
Fax: (866) 464-3616
http://nccam.nih.gov/health/supplements.htm



Private Organizations

National Mental Health Association
Mental Health America
2000 N. Beauregard Street, 6th Floor
Alexandria, VA 22311
Phone: (800) 969-6MHA (6642)
TTY: (800) 433-5959
Fax: (703) 684-5968
http://www.nmha.org

Mayo Clinic
4500 San Pablo Road
Jacksonville, FL 32224
Phone: (904) 953-2000
http://www.mayoclinic.org

National Women's Health Network
514 10th Street, NW, Suite 400
Washington, DC 20004
Phone: (202) 628-7814
http://www.nwhn.org


Newsletters, Magazines, Reports

Healthy Women Today
The National Women's Health Information Center
http://www.womenshealth.gov/newsletter

FDA Newsletter
Check out the FDA electronic newsletter for updates on dietary supplements.
http://www.cfsan.fda.gov/~dms/fda-dsfl.html

Dietary Supplement Information Bureau
Sign up for the newsletter.
http://www.supplementinfo.org/newsletter.asp


Tools

News In Health
"Supplementing Your Diet: Vitamins, Minerals, and Beyond"
http://newsinhealth.nih.gov/2006/March/docs/01features_01.htm

Dietary Supplement Health and Education Act of 1994
Read the legislation passed by the FDA.
http://vm.cfsan.fda.gov/~dms/dietsupp.html

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