- Adventist Health Victoria

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Transcript - Adventist Health Victoria

Unit 14
Prepared by Sibilla Johnson, B.Sc. Nutrition
Ref: Craig W; ‘Nutrition and Wellness’ 1999. Wahlqvist M; ‘Food and Nutrition’ 2002
Vitamin Supplements
Some studies on the use of
supplements have had some very
negative findings
• A study using beta-carotene (thought to
protect against cancers and heart disease)
had to be stopped, because mortality was
higher in the people taking the supplements
• A study of 22,000 men taking betacarotene for 12 years found that they were
no better off than the men on placebo
(dummy tablets)
• A study of 18,000 smokers and former
smokers found that those who took betacarotene supplements had almost 30%
increased chance of developing lung cancer
compared with those who took a placebo
• In another study subjects taking betacarotene supplements developed more
bowel polyps
• The latest study from Copenhagen looked
at 14 separate trials to see if antioxidant
vitamins A, C and E decreased the incidence
of intestinal cancers.
Conclusion: “We could not find evidence
that antioxidant supplements can prevent
gastrointestinal cancers, on the contrary, they
seem to increase overall mortality”.
Dietitian Matt O’Neil believes:
• Vitamins can cause more harm than good.
The types of antioxidants in fruits and
vegetables have been shown to reduce risk
better than higher doses in vitamins
In the U.K.
• The Food Standards Agency has taken to
warning consumers about the risks of
overdosing on certain vitamins
Associate Professor Caryl Nowson
(A Nutritionist at Deakin University)
• Vitamin A is her chief concern: “You can
certainly overdose on vitamin A & D. And
Vitamin E has been found to be detrimental
in terms of cancer risk” she says.
• “Vitamin A is a particular worry during
pregnancy, if women are taking a Vitamin A
supplement it can cause skeletal deformities
in the infant”.
• “We also have some evidence to show
Vitamin A is associated with increased risk
of fractures for older people”.
If supplements are taken they should
be below the RDI (recommended daily
intake), high intakes are to be avoided
Taking vitamin supplements should
be viewed as a short term measure.
The long term use of supplements can
lead to symptoms of overdosing.
If you feel that you could be lacking in
certain vitamins and minerals, it may be
better to look at changing your diet and
lifestyle rather than reaching for
supplements
Vitamin Deficiencies
Your body only needs a small amount of
vitamins everyday.
A varied diet generally provides enough of
each vitamin and mineral.
However, there are people who may benefit
from supplements and they include:
• Pregnant women
• Women who are breastfeeding
• Alcoholics
• Cigarette smokers
• Illegal drug users
• Crash dieters or people on chronic lowcalorie diets
• Some vegetarians
• People with allergic reactions to certain
foods
• People with malabsorption problems,
such as diarrhoea, coeliac disease or
pancreatitis
• The elderly, those that are disabled or
chronically ill
Vitamins from food are best!