dietary supplements

Question 1

who in the general population is likely to be at risk of
vitamin or mineral malnutrition

Answer 1

1. vegeterians/vegans
2. elderly
3. malnutrition
4. malabsorption
5. alcoholics

Question 2

evidence for the use of vitamins and minerals in general population

Answer 2

1. some evidence choline has benefits on memory and behavior
2. in vitro studies suggest glucosamine (part of cartilage) can increase cartilage synthesis (used for osteoarthritis)
3. creatine increases energy in athletes by producing ATP needed for short term energy store in skeletal muscle
4. pre and probiotics may be useful for IBD and acute diarrhoea. some proposed uses for diabetes, obesity, psychiatric disorders, fatty liver disease. mechanism not known maybe compete with pathogens for nutrients
5. some evidence that stanols decrease serum cholesterol and LDL cholesterol. (compete with cholesterol for uptake) not v. effective on their own good complement.
6. some evidence that fish oils beneficial for rheumatoid arthritis.

Question 3

evidence against the use of vitamins and minerals in general population

Answer 3

1. no evidence vitamin c reduces duration or severity of colds
2. no evidence antioxidant supplements (A, C, E, Selenium) decrease mortality rate
3. beta carotene supplements can increase risk for lung cancer
4. no evidence for effx of coenzyme q10 hypertension or heart failure (required for etc to produce energy) theoretically helps preserve mitochondrial funtion which can protect cells from aging. not very bioavailable
5. no evidence for effx of choline in dementia
6. no evidence for asthma, cardiovascular disease, cognitive decline and IBD prevention with fish oils

Question 4

what are legal issues around dietary supplements

Answer 4

classified as foods, food laws apply not controlled under medicines act no sale restrictions no license requirement.
cannot make medicinal claims

Question 5

what are classifications of dietary supplements

Answer 5

1. vitamins and minerals
2. unofficial vitamins and minerals (no evidence for requirement or deficiency)
3. natural oils with fatty acids and pre/probiotics
4. natural substances (herbal ingredients)
5. enzymes
6. amino acids and derivatives
7. food supplements (high calories)
8. slimming products

Question 6

what are some potential risks of dietary supplements

Answer 6

drug-supplement interactions ex: warfarin and vitamin E both thin blood

some supplements have doses above the safe dose for deficient people.
zinc above safe dose can cause gi effects and anemia
B6 above safe dose can cause peripheral neuropathy
increased doses of vitamin A can cause increased risk of osteoporosis.

benefits of getting extra vitamins and minerals not clear.

prebiotics could also increase growth of pathogenic bacteria