WHAT IS A DIETARY SUPPLEMENT?
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Transcript WHAT IS A DIETARY SUPPLEMENT?
B IOLOGICALLY ACTIVE SUBSTANCES
D IETARY S UPPLEMENTS
F OODS
OR
D RUGS ?
D IETARY S UPPLEMENTS
Alternative therapies and
natural remedies
(Wholistic Medicine
Dietary supplements = 6.5
billion / Prescription Drug
sales = 85 billion
Increased consumer
dissatisfaction with
conventional health care
½ of US population use
Dietary Supplements
3
H ISTORY OF D IETARY
S UPPLEMENTS
1938 Act established standards of identity for
vitamins and minerals
Proxmire Amendments extended FDA
jurisdiction to advertising of Vits and mins
Prohibited FDA from setting max limits on
potency
Forbade FDA from classifying supplements as
drugs
H ISTORY OF D IETARY S UPPLEMENTS
1990 Nutritional Labeling and Education Act
Permitted use of therapeutic claims made about vits/mins
1994 President Clinton signed Dietary Supplement, Health
Education Act (DSHEA) into law
Defined D/S as “separate regulatory category of food”
W HAT
IS A
D IETARY S UPPLEMENT ?
Definition:
A product (other than tobacco) intended to supplement the diet
that bears or contains one or more of the following dietary
ingredients
Vitamins
Minerals
Herbs or other botanicals
Amino acids
Concentrate, metabolite, constituent, extract or combination of
above listed ingredients
D IETARY S UPPLEMENTS
Traditionally defined as products made of one or more
essential nutrients such as vitamins, minerals, and proteins,
but…
DSHEA broadened definition to include almost any product
intended for ingestion as a supplement to the diet
Must be identified on label as a D/S
D IETARY S UPPLEMENTS
Distinguished from Drugs:
Drug = article intended to diagnose, cure, mitigate, treat, o
prevent disease
Both intended to affect structure and function of body
Drug must undergo FDA approval after clinical studies to
determine effectiveness and safety
D/S = no pre-market testing
D IETARY S UPPLEMENTS
Distinguished from Foods:
Foods not intended to affect structure and function
D/S intended only to supplement diet
Not represented for use as conventional
food
Not intended as sole item of a meal or
the diet”
D IETARY S UPPLEMENTS
No premarket approval
Manufacturer responsible for safety evaluation
If D/S contains a new ingredient:
Manufacturer must submit information that ingredient “can
reasonably be expected to be safe” within 75 days of
marketing
Safe = no significant risk of illness
N UTRACEUTICALS / F UNCTIONAL F OODS
Nutraceuticals / Designer foods / Phytochemicals /
Functional Foods
“any food or food ingredient considered to provide
medical or health benefits, including prevention and
treatment of disease
T ERMINOLOGY
Nutraceuticals
Functional Foods
Nutrient rich products with limited health claims
Any modified food or ingredient that may provide a benefit
beyond the traditional nutrients it contains
Phytochemicals
Such foods that are derived from naturally occurring
ingredients
S OME E XAMPLES :
Benecol
“Plant stanol esters”
Glucosamine
New Approved Health Claims
Flavonoids (Teas) and heart
disease
Supplements, here, now.
Sales DS about $13 billion in 2000, growing 5% yr
Mayo Clinics 5/99: 61% pts said had used DS
FDA 1995 survey data > 55% adults
5/00 Texas HMO survey: 40%
Use elderly, females, white, obesity, EtOH
Most used per friend,relative, did not ask MD, Pharm
Most felt herbals “safe” and “no side effects”.
6/99 JFP: most said “MD’s closed minded, don’t know about DS”
Supplement regulation
1906: FDA to eradicate “misbranding and adulteration”
1938: FDA requires testing prior to marketing after
health elixir kills 105– but allows traditional herbs
1958 – 1993: GRAS list 250 trad. HS
1962: Thalidomide. Kefauver-Harris laws require proof
safety, efficacy, burden of proof on manufacturers.
New law, New label
1993: FDA proposal removal of HS from market if don’t
meet rules. Congress deluged c protest, $$ ads
1994 FDA (de) regulations: DSHEA
List ingredients, allowed nutrition claims on labels
Manufacturer responsible for safety
“This product has not been tested or approved by the
FDA and makes no claim to diagnose, treat, cure or
prevent any disease.”
“This product has not been tested or approved by the FDA and makes no claim to diagnose, treat, cure or prevent any disease.”
Hey what’s in that bottle?
Ingredient mixups harvest bottle
Belgium: ARF: Fang-ji (Stephania tetandra) slimming herbal –
consumed: Fang-chi (Aristolochia)
Contamination
1990 L-tryptophan “E” 1000 eosinophilia, 38 deaths
Lead: “natural” Ca, 1994, 2000 -- Azarcon, Rueda
Kombucha “antioxidant, tonic” yeasts + soil bact (+ anthrax)
Adulteration
Unlisted ingredients–NSAIDs, steroids
1995 aplastic anemia- Phenylbutazone “natural” cold Rx.
More trouble
Interactions
Dong Quai, Tonka Beans– natural coumarins
Grapefruit Seed – Cyto P450 inhibitor
Overuse, “More is better” dosing (evidence in athletes)
Vit C– mega procarcinogen, calculi
Ginseng overdose syndrome– aggression, manias
Abuse
“Herbal Ecstasy” Ephedra, “Liquid ecstasy” GHB
Artemesia Absinthium (Oil of Wormwood)- thujone, neurotoxin
Testing?
“Consumer Lab” testing 6/00:
Vit C (n=26): 15% failed. (<95% amt claimed)
Glucosamine/ Chondroitin (n=25): 30% failed
Gingko, Saw Palmetto, Methionine… similar.
Products “passed” see ConsumerLab website
Many calls for 3rd party review- FDA hearings, 2000
NIH Office of Alternative Medicine– underfunded
1997 Fed Commission on DS: “Rec scientific evidence”.
Meanwhile, we’re stuck
GRAS/ German Health Authority 1998 Comm. E publ, 300 HS
URI
Echinacea (e. purpura, purple coneflower, 9 spp)
Biggest selling HS in US, as it was pre-abx.
RCT’s 1993, 94, show some URI sx, proph. RCT’s 98, 99 Ø.
Animal Studies: WBC, cytokines.
No sig toxicity known. Usual dose 50 drops, or 400 mg tid.
Zinc Gluconate, “Cold Ease”
RCT x 2 1996, ‘98 conflicting. Nausea at effective doses (qid)
Licorice (Glychyrrhiza glabru) For cough. Avoid - aldosterone
Ephedra / Ma Huang
Ephedra / Ma Huang
Stimulant, weight loss, decongestant
Ephedrine: sympathomimetic, vasoconstrictive effects.
>3 billion products containing sold in US per yr
>1400 rpts to FDA 1999-2001 (HTN, CV, CVA, sz, )
Poison Cntrl: 876 rpts 1997-99 (ASA 2000 qy)
12/00 NEJM review 31% “probably” + 31% “possibly” caused
Interactions- MAO inhib’s: life threatening
Banned by the NFL, etc.
Weight Loss
“Metabolife”, “Herbal Phen-Phen”…
Ephedra, St. John’s Wort, caffeine
Phenylpropanolamine- avoid
Use with caution per individual ingredients
“No effect” trials: Garcinia, Yohimbine, creatine, DHEA
Unknown effectiveness: Cola Acuminata, Dwarf Elder,
Germander
Sedatives / Hypnotics
Melatonin
Pineal hormone, normal trigger bright light
Irregular sleep cycles of blind pts improve c melatonin
Studies: Ø effect nl patients sleep latency, quality
Usually safe, if pure product.
Chamomile
Apigenin, binds benzo receptors, mice: mild sedative
Cross rxn’s ragweed allergy.
GRAS, no adverse rpts pregnancy, lactation. Tea prn.
Still not sleepy?
Valerian (Valeriana Officialis root)
Effective per 2 small RDBCT. In-vitro binds GABA, like benzo’s
Some pts paradoxical effects. Not rec pregnancy.
GRAS, long hx use, no sig toxicity. 400 mg qhs.
Kava-Kava (Piper methysticum)
Some evidence better than placebo, Oxazepam 15 mg
Very heavy use: reports of adverse sx.
Generally safe, intermittent use no known toxicity.
Mistletoe, Catnip, Gutu kola, Hops, Lavendar, Skullcap
Passionflower… No evidence.
St. John’s Wort (Hypericum perforatum)
2nd most popular HS. Effective per 1996 meta-analysis.
MAO (-) ?, SSRI. Interactions, photosensitivity
Avoid pregnancy- ctx. Case reports thrombocytopenia.
300 mg tid TCA’s, amytriptilene 75mg qd
NIH currently studying vs. fluoxetine.
Gingko ( G. biloba)
Dementia, memory. Some evidence intracerebral circulation
Gingkolides: (-) PAF, bleeding rpts.
Germany: (Egb 761), US trials: similar to tacrine, donezepil.
Gingko seed: neurotoxin. Egb 761 (leaf extract) 80 mg bid
Athletics I
Creatine: Big sales, Big stars
Precursor to creatine phosphate, ADPATP
Small wt bodybuilders (? H20). ? Weight lifters, sprinters.
Ø effect rowers, swimmers, cyclers, runners
Elderly Ø effect. Serum creatinine can .
Caffeine blocks ( - phosphocreatine resynthesis)
Probably safe : 20g qd x 1 wk, then 5g qd. (Diet 1-2 g qd)
Chromium
Ø evidence efficacy.
Anemia concern: binds transferrin
> 600 g qd RF. Not rec. but probably safe < 200 g qd
Athletics II
Androstenedione, DHEA
Testosterone precursors, oxytestosterone. Estrone may
Studies: Ø effect performance or muscle mass but HDL ~ 5.
GHB (gammahydroxybutyrate)
“Growth hormone releaser” No evidence effective.
“GHB intoxication” syndrome: MS , coma,13% intubated
Banned FDA for OTC, but still available internet
GBL (gammabutyrolactone) available, similar toxicity
Amino acids, muscle tonics: Ø evidence. Carbo load better.
Anti-inflammatories
Glucosamine/ Chondroitin
Meta-analysis (flawed) studies : moderate sx OA.
Less SE’s than NSAIDS
Some RCTs show progression OA (unlike NSAIDs)
Feverfew (Tanacetum parthenium)
Arthritis: Ø effect in studies. Conflicting evidence for HA’s.
Parthenolide (-) arachadonic acid, serotonin.
Rebound HA, nausea common. Avoid in preganancy, ctx.
Commercial prep’s weak, “placebos”.
Not recommended
Anti-inflammatories to avoid
Chaparral / Creosote Bush/ Greasewood
(-) cyclooxygenase, lipoxygenase
Chronic use assoc hepatitis/ hepatic vein occlusions
Aconitum
Opens cardiac, neuronal Na channels
SE’s similar to cardiac glycosides, vent Dysrhthmias, neuro
Arnica
Long traditional use but not rec. due reports hepatitis, myalgias
Homeopathic preps probably safe, low concentration
Antioxidants / Cancer
Selenium
Intracellular metalloid assoc with glutathione peroxidase
Selenosis in overdose amounts- similar to arsenic
No evidence effectiveness.
Vitamin A
Frequent toxicity reports
Megadose levels > 25,000 IU/kg ICP, hepatotoxic
Chronic use > 4,000 IU/kg neuro, hepatic, derm sx
Beta-carotene: Slow absorbtion, no Vit A toxicity
Skin discoloration
Avoid in smokers
Antioxidants / Cancer
Vitamin E
No evidence anticancer effectiveness.
CHD: Large trials (HOPE, GISSI) now show no benefit CAD pts.
Physician’s Study 2001, Vit E CV death rate.
Extreme doses– anti-coagulation, but wide safety margin.
Vit C:
Studied more than any other DS but no proof definitive benefit
Procarcinogenic, nephrolithiasis in some studies hi doses
MANY-- Green Tea, Glutathione, Gingko, Grape Seed, nacetylcysteine, Melatonin, Bilberry, curcumin, Laetrile...
General Tonics
Garlic (Allium sativum)
HTN: maybe 5%, cholesterol: probably Ø
Allicin degraded by crushing, heat, acid.
GRAS, rec dose: 1 clove qd. Commercial tabs 93% Ø allicin.
Comfrey tea
“Wound healing” no evid. but may be carcinogenic, hepatotoxic
Esp. avoid pregnancy (DNA damage in vitro), lactation.
Ginseng (Panax ginseng) “Siberian g” (E. Senticosis)
Mild stimulant, no other proven.
Ginsenosides: wide variation of content
GRAS, rare mastalgia, PMP bleed. “Ginseng abuse syndrome”
GI
Hepatitis: Milk Thistle (St. Mary’s Thistle, Holy Thistle)
Sylmarin: some evid. LFT’s, esp in EtOH cirrhosis
Europe uses IV, mortality 50%, mushroom poisoning cases
GRAS: Long used safely as food in Mideast
Diarrhea: Goldenseal (Hydrastis canadensis)
Berberine: intraluminal antidiarrheal (E. Coli, Vibrio studies)
Drug screens: doesn’t mask.
Contraindicated: pregnancy, lactation, anti-coagulation, sz.
See also pregnancy, below
CAD: Is Merlot a Vitamin?
EtOH and cardiac dz:
490,000 pts: 1 qd 21% overall mortality, 30-40% CHD.
Evidence 2-6 drinks qw 34-53% CHD mortality, overall 28%.
But: heavier drinkers 51% overall mortality.
Other agents
Omega-3 CVA, MI in post-MI pts. (GISSI prevention trial)
(850mg eicos + 750 mg decos qd)
Folate, Vit B6 homocysteine, unk. effect on CHD.
Diet works: low Na, DASH and Ornish…& exercise
Female
Pennyroyal (Hedoma pulegioides)
Birth control, ctx. Hepatoxicity, neurotoxic, deaths. Teratogen.
Pulegone – effects similar acetomin toxicity, TD 10ml. Avoid.
Blue / Black Cohosh
Midwives: cervical ripening, labor,menopause. Does seem ctx.
Possible teratogenic effects, in-vitro coronary artery constrict.
Soy / isoflavones (Many formulations, inconsistent dosing)
Ob/Gyn 2000 review: Some menopause sx, prob safe.
Evening Primrose Oil- Some evidence breast sx relief, GRAS
Pregnancy
UCSF 1999-00 150 pts, 13% used, 75% reported
Similar stats: 2000 N. Carolina midwives study
Echinacea 9%,
Not rec. By German Commmission E > 8 weeks
Recent study 5-7 d, 206 women all trimesters: no malformations
Pregnancy Tea 9%
Spearmint, raspberry, strawberry, nettle, rosehip, lemon
verbena, alfalfa “uterine toner”. No data x use.
Nausea/ pregnancy
Ginger (Zinziber officinale) 7%
Nausea: data mixed, but results similar to Reglan.
70% vs. 15% placebo (n=27), other RCDBT also good results.
Contraindicated in bleeding disorders. (- Thrombox synth)
GRAS, rec. dose ¼ to 1 g powder qid.
B6 / pyridoxine 2%
Nausea/ hyperemesis: some evidence helpful
No known toxicity, 50mg po tid rec.
Male
Saw Palmetto (Serenoa Repens)
BPH some evidence sx, (flow, nocturia)
In-vitro 5- R (-), similar to finasteride, not effective as 1(-)
Few side effects (HA, GI). Usual dose 160 mg bid.
Yohimbine (Pausinystalia yohimbe bark) ED: central adrenergic feedback inhib– HTN, emesis
Ch’an Su (Bufo toad)
Bufalin aphrodisiac- sx similar to dig toxicity (Digibind)
Elderly
“Aggressive marketing tactics”
Atrophic Gastritis
Affects 1/3 elder adults -- past h.pylori usually
Absorbtion Fe, Folate, Ca, Vit K, Vit B-12
Intolerance of lactose/dairy further Ca.
Overall small intestine, pancreatic fxn stays intact
Nutritional health most affected mobility, diet, $
RDA’s need further study for elders per recent FDA rpts
Kids
Avoid all but the safest DS
Fluoride – Effective preventer tooth decay.
Public Health Service Rec [.7-1.2 mg/ L]. Seattle 2001 [1mg/L]
Supplementation Recs per AAP if H20 < .6 ppm.
No evidence current levels carcinogen, etc.
Flouride Overdosing?
Poisonings: 1992 Alaska, ‘93 Hawaii, ’98 Miss. All 200 mg/L
Fluorosis: Usually small opaque areas tooth, can be brown
Avoid excess flouride/ toothpast in kids- rice sized glob enough