Some health stores recommend brewer's yeast as a natural way of reducing cholesterol - but does it work, and is it safe?
Brewer's yeast, which is essentially a powdered fungus used in beer production, is one of the many wonder products you can find in a health food store. It is sold both as a way of getting B vitamins and chromium, and is sometimes claimed to reduce cholesterol. This claim is based on a number of studies - but the evidence is weak, with some studies showing no effect at all, and several centres of expertise suggest there is no basis for the claim.
What is certainly true is that where it has been suggested that brewer's yeast has a cholesterol reducing benefit, the product is being taken in doses of around 500mg a day (1-2 tablespoons in powdered form). One concern this raises is that this would result in receiving around 1,000% of the RNI of niacin ((the amount that is enough, or more than enough for 97% of the population), and there is good evidence that high doses of niacin can have negative effects. There are simpler ways to reduce cholesterol.
The other claimed benefits of brewer's yeast tend to be from the trace mineral chromium (for which there are various claims with mixed evidence) and a source of B vitamins, but as we make clear in the Vitamins and minerals section (page 111) a normal adult on a balanced diet should not need supplementation. By all means enjoy the brewer's yeast containing spreads like marmite or vegemite if you are in the 'love' camp - but it seems unlikely that it will provide much benefit as a supplement.