A new study concludes that intake of vitamin A, vitamin E and beta-carotene seems to increase mortality. The National Food Institute, Technical University of Denmark finds the study thorough and reliable and thus recognises the results.
The Danish Veterinary and Food Administration has asked the National Food Institute to assess a new study conducted by researchers from Copenhagen University Hospital, among others. The study is a systematic literature review (SLR) aimed at examining beneficial and harmful effects of antioxidant supplements in relation to preventing adult mortality. The study includes 78 studies from all over the world with a total of 296,707 participants.
The study concludes that no preventive effects have been found from taking antioxidant supplements, but rather that beta-carotene and vitamin E as well as increased doses of vitamin A appear to increase mortality among adults. The further conclusion is that antioxidant supplements should be considered as pharmaceuticals and thus be subject to the necessary evaluation before being marketed.
The results also support previous study results of a similar SLR from 2008. The new study includes a further 11 new studies, i.e. an additional 64,000 participants compared to the 2008 study.
Assessing the study
The National Food Institute finds the study to be thorough and the conclusions to be based on high-quality individual studies. The assessment is based on an internationally recognised check list for quality assessing SLRs. On a scale from A to C, the study received an A score corresponding to “reliable”. The National Food Institute thus recognises the study results.
The study did not aim to examine the doses required to trigger beneficial or harmful effects. On this basis, the National Food Institute points out that the study results cannot immediately be used to assess which doses of vitamin A, vitamin E or beta-carotene may lead to over-mortality.
Diet usually covers basic vitamin requirements
Dietary habit surveys conducted by the National Food Institute show that, with a few exceptions, most Danes are able to cover their vitamin and mineral requirements through their normal diet without requiring supplements. You do not have to fear getting too many vitamins and minerals through your diet. The only recommended supplements are:
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Combined supplements of vitamin D and calcium for all aged 70 and above as well as people at risk of developing osteoporosis
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Supplements of vitamin D throughout the whole year for men and women with dark skin
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Iron supplements for pregnant women and folic acid supplements for women planning pregnancy
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Adults that for different reasons eat relatively little or children with very unbalanced diets may benefit from taking a multi-vitamin pill.
The National Food Institute generally advises against a high vitamin intake from supplements as it increases the risk of exceeding the upper safety limits. However, this does not apply to doctor-prescribed supplements.
Read more
The study was published in the Cochrane Database of Systematic Reviews: Antioxidant supplements for preventing of mortality in healthy participants and patients with various diseases.
For more information about the recommendations of the Danish Veterinary and Food Administration on supplements and multi-vitamins www.altomkost.dk. See also the press release (in Danish) from the Danish Veterinary and Food Administration Tag trygt en multivitaminpille (in Danish).
Contact
Gitte Gross, Head of Division, gigr@food.dtu.dk, tel. +45 35 88 74 11