DIET

How do you ensure that your selenium intake is adequate?

Dietary Supplement Fact Sheet: Selenium

Selenium availability from soil

In Norway the concentration of Se in soil is 0.4-2.7 mg/kg. But only about 4% of this is extractable (in warm water).

Thus the availability for plants is relatively low, leading to low levels in locally produced plants. In Norwegian wheat the level is 0.5-1.9 µg/100 g. In North American wheat it is much higher.

Selenium in fish

Fish contains a high concentration of selenium, but it is not bioavailable. Why?

• Antagonist with mercury?
• Antagonist with arsenic?
• Intake of unsaturated fatty acids in fish leads to increased oxidative stress, increased turnover of GSH, and loss of Se?
• Well absorbed, but an alternative metabolic fate?

Selenium and health in Norway

Norwegians have been at the top in Europe with respect to selenium levels in the blood. This position presumably results from the high level of imports of wheat from countries such as Canada with high levels of Se in the soil. With an increase in the share of home-produced wheat, selenium status of the population will decline (as it has already in Britain). The significance of this for public health is uncertain.

Recommended selenium intake

USA:

• Women 55 µg/day
• Men 55 µg/day

Nordic countries:

• Women 40 µg/day
• Men 50 µg/day