Food Politics

Amanda asks: “I also read that once you take the fat out of milk, it is difficult to absorb the calcium from it. Marion, can you state whether this is true?”

Oops. No. Where this idea came from, I can only guess. Fat is required for absorption of fat-soluble nutrients like vitamins A and E but minerals like calcium are water-soluble so would be expected to be absorbed better from watery solutions. As it turns out, calcium absorption has been measured under all kinds of fat conditions. The result: about the same proportion is absorbed from dairy products–about 30%–no matter how much fat they have. We tend to absorb smaller proportions of calcium from foods that contain a lot of oxalates (spinach and rhubarb for example). When dairy products are added to spinach, more of the spinach calcium is absorbed, so maybe that’s where the idea came from. Does this help?

And while we are on the subject, how’s this for a proposed solution to the non-problem of calcium absorption: genetically modified carrots! Bet you never thought of that one.

A new analysis of all kinds of studies on the use of calcium to prevent fractures is just out in the American Journal of Clinical Nutrition. The results? “calcium intake is not significantly associated with hip fracture risk in women or men…[results] show no reduction in hip fracture risk with calcium supplementation, and an increased risk is possible.” It sure would be nice if it were that easy to prevent fractures but bone strength requires a good diet containing ALL nutrients, not just calcium (with or without vitamin D), as well as plenty of physical activity, so these results should not come as a surprise. The bottom line: eat healthfully and move!