Radioactive strontium (Sr 90) is a hazardous by-product of nuclear fission. Taking trace amounts of strontium may possibly protect us from picking up the radioactive form when exposed to it. Generally, we do not need to worry about strontium, even if it is essential, because it is available in most diets, through the soil. This means that the strontium content in food will vary geographically.

Strontium absorption varies from about 20-40 percent. It is stable in the tissues, mainly the bones and teeth, and most extra strontium is eliminated in the feces.

Sources: Strontium is present in seawater and some other waters. Soil content may vary. Strontium is found, generally in low amounts, in most foods.

Function: Strontium may help improve the cell structure and mineral matrix of the bones and teeth, adding strength and helping to prevent tooth decay or soft bones, though it is not known if low body levels of strontium causes these problems.

Uses: There are no clear uses for supplemental strontium. The use of strontium to help bone metabolism and strength in osteoporosis has been investigated, but is still questionable. Whether strontium will prevent tooth decay has not been shown. As stated, trace amounts of nonradioactive strontium may be taken to reduce uptake of the radioactive form of this element.

Deficiency and toxicity: There have been no cases of known toxicity from natural strontium. Nor are there any deficiency symptoms related to humans, though in rat studies, strontium deficiency may correlate with decreased growth, poor calcification of the bones and teeth, and an increase in dental caries.

Requirements: There is no RDA for strontium. Food intake may supply us with about 2 mg. daily.