A little selenium goes a long way

The Department of Health's recommended daily selenium intake is 75 μg (micrograms) for men and 60 g for women. That's about the amount contained in a small can (20-25 g) of tuna. Other selenium-rich foods include Brazil nuts and kidney while beef, shellfish and chicken also contain relatively large amounts of the element. In general, however, selenium intake in Europe has fallen dramatically in the past 30 years. The average person in the UK now gets about half of the recommended amount in their diet. 

Scientists believe the problems began when the UK stopped importing Canadian wheat and switched to home-grown varieties. Canadian bread-making wheat can contain up to 50 times more selenium than the UK equivalent because it is grown in soil that is naturally selenium-rich. In contrast UK soil contains very little selenium. What, then, is the role of selenium in the body, and are such deficiencies a cause for concern?