Dietary Supplements
Dietary Supplements
• Majority of adults in US take 1+ dietary supplement either every day or occasionally
• May include vitamins, minerals, herbals, botanicals, amino acids, enzymes, others
• Can be in tablet, capsule, powder, drink, energy bar forms
Na#onal Ins#tutes of Health, Office of Dietary Supplements, Dietary Supplements: What You Need to Know, 2011
Supplement Sales
Dietary supplement sales in the US are $22.5 billion per year (2006)
Source: Natural Products Founda#on’s Dietary Supplement Informa#on Bureau, 2009. Image: Jose Paolo S. Borromeo
European Union
• EU Food Supplement’s DirecMve of 2002 • Establishes purity criteria • Must be proven safe before sale • Must be labeled “this is not a medicinal
product” if similar to medicinal product
United States
• Dietary Supplement Health and EducaMon Act of 1994 (DSHEA)
• Includes vitamins, minerals, herbs, botanicals (except tobacco), amino acid or combinaMon of any of these used to supplement the diet
• Regulated as a category of foods, not drugs • Don’t have to prove efficacy or safety before sale –
FDA regulates aYerwards if safety issues arise • Enforcement is spoZy, industry largely unregulated
Dietary Supplement Facts Panel
Quality
• Quality standards exist – although may be quesMonably reinforced
• IdenMty, purity, strength, composiMon • Independent, extra-‐governmental
organizaMons may add addiMonal quality tesMng: U.S. Pharmacopeia, ConsumerLab, NSF InternaMonal
Concerns
• May contain trace amounts of lead and other contaminants
• May displace income that could otherwise be used for Rx drugs and healthy foods
• Users do not always disclose to pracMMoners; pracMMoners do not always ask about supps
• Herbals can contain dozens of compounds and acMve ingredients may not be known
Supplement Savvy
• “Natural” means nothing • “High-‐potency”, “pharmacy-‐grade”,
“prescripMon-‐strength” • Self-‐diagnosing is harmful • More expensive supplements ≠ beZer quality • Some may interact with prescripMon and
over-‐the-‐counter medicaMons
Contraindications
• Vitamin K can reduce ability of blood thinner Coumadin to prevent blood from clofng
• St. John’s wort can expedite breakdown of many drugs – including oral contracepMves and anMdepressants – and reduce effecMveness
• AnMoxidants such as vitamins C and E may reduce effecMveness of certain chemo therapies
Na#onal Ins#tutes of Health, Office of Dietary Supplements, Dietary Supplements: What You Need to Know, 2011
IOM Tolerable Upper Intake Levels Nutrient UL Nutrient UL
Vitamin A 3,000 mcg Iron 45 mg
Vitamin C 2,000 mg Magnesium 350 mg
Vitamin D 100 mcg Manganese 11 mg
Vitamin B6 100 mg Molybdenum 2,000 mcg
Vitamin E 1,000 mg Niacin (Vitamin B3) 35 mg
Calcium 2,000 mg Phosphorus 4,000 mg
Choline 3,500 mg Selenium 400 mg
Copper 10,000 mcg Zinc 40 mg
Folate (Vitamin B9) 1,000 mcg No UL for: thiamin, riboflavin, pantothenic acid, biotin, vitamin B12, vitamin K, chromium or carotenoids
Claim: “Promotes joint health” • “Joint health” = $800 mil/annual sales • Glucosamine & chondroiton – mostly negaMve results • 2006, Glucosamine/ChondroiMn ArthriMs IntervenMon Trial
(GAIT) found no clear benefit for most paMents • 2009, RTC found glucosamine + chondroiMn no more
effecMve than placebo to slow carMlage damage from OA • 2010, Norwegian researchers tested glucosamine for
chronic LBP & degeneraMve lumbar OA, no significant difference between glucosamine & placebo
NEJM 2006 Feb 23;354(8):795-‐808; JAMA 2010 Jul 7;304(1):45-‐52
Claim: “Improves memory, focus” Ginkgo EvaluaMon of Memory (GEM) • Randomized, double-‐blind, placebo-‐controlled trial of
3,069 people age 72-‐96 at 6 academic medical centers • Twice-‐daily doses of 120 mg ginkgo extract did no beZer
than placebo to slow cogniMve decline over 6 years • Earlier GEM findings: debunked benefit against
Alzheimer’s & demenMa • DeKosky, UVA author, “I’ve got no good reason to suggest
you conMnue to take it beyond your own blind faith”
JAMA 2009 Dec 23;302(24):2663-‐70; JAMA 2008 Nov 19;300(19)2253-‐62.
Claim: “Prevents aging” • Resveratrol: anMoxidant found in red wine • Appears to inhibit enzymes that regulate cell energy • 2006, Improves health & longevity of overweight, aged mice • 2008, May slow age-‐related deterioraMon and funcMonal decline of
mice on a standard diet – doesn’t increase longevity when started at middle age
• Clinical studies of resveratrol in humans use 1 g/day = 667 boZles of red wine
• Long-‐term effects & safety are unknown • Great example of exploiMng preliminary animal study data for
profit before science unquesMonably can prove benefits
Cell Metab 2008 Aug;8(2):157-‐68;
Who May Need a Supplement? Group Why?
Dieters <1600 kcal per day may benefit from vitamin/mineral supplement
Vegans, no dairy Vitamin B12, calcium and vitamin D
Infants, children Fluoride, vitamin D, iron
Pregnant women 400 mcg folic acid from forMfied foods or supplements; prenatal vitamins
Older adults Vitamin B12 (gastriMs, decreased IF producMon), calcium and vitamin D
Darker skin Vitamin D
CigareZe smokers Vitamin C – helps prevent cigareZe smoke-‐induced oxidaMve damage
Alcohol abusers B vitamins – alcohol inhibits B vitamin absorpMon and metabolism
MedicaMon Many medicaMons may interfere with normal vitamin/mineral metabolism
In Summary • Just because you don’t need a prescripMon doesn’t mean a
supplement is harmless • Don’t waste Mme and money on supplements if you don’t
need to • Changing diet and exercise paZerns IS harder than
popping a supplement pill • Most individuals can obtain all nutrients from foods alone • When supplements are indicated, they should be taken
with cauMon and under the supervision of a qualified medical professional
For More Information • Office of Dietary Supplements, Dietary Supplement Fact Sheets:
hZp://ods.od.nih.gov/factsheets/list-‐all/ • UC Berkeley, Berkeley Wellness LeZer Dietary Supplements
Guide: hZp://www.wellnessleZer.com/ucberkeley/best-‐of-‐wellness/dietary-‐supplements-‐guide/
• MedlinePlus, Herbal Medicine: hZp://www.nlm.nih.gov/medlineplus/herbalmedicine.html
• NCCAM, Using Dietary Supplements Wisely: hZp://www.nccam.nih.gov/health/supplements/wiseuse.htm
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