Relationship between calcium, Vitamin D and fat

DEAR DR. BLONZ: My nutritionist friend keeps telling me that calcium from fat-free milk products is not absorbed into the body. She says calcium needs to be consumed with a little fat in order to be absorbed, and that my body is not absorbing any calcium from all the fat-free milk and yogurt I eat. Is this true? Do I need to switch to low-fat milk products for the best bone health?

— S.F., Phoenix

DEAR S.F.: I question this information from your friend. The calcium absorption from these dairy products would not be significantly different between fat-free and low-fat versions. You can make the switch if you want, but do so for other reasons.

Consider the possibility that your friend may have confused calcium with vitamin D: a fat-soluble vitamin that does experience better absorption when it is consumed alongside some fat. This would be understandable, as the two nutrients are connected. Among other functions, vitamin D forms the calcium-binding protein that facilitates the absorption of calcium from the foods we eat.

In order to have the calcium-binding protein ready, the body needs adequate vitamin D levels in place before calcium-containing foods, such as dairy, are consumed. If the body is deficient in this vitamin, this cannot be overcome by simply consuming vitamin D and calcium in the same meal; the vitamin D would help with calcium absorption in future meals, but not that one.

DEAR DR. BLONZ: I inherited the family genes for high blood pressure, so I know there are limits to how well I can manage it with diet alone. I enjoy cooking, I watch my sodium intake and I don’t use too many processed foods, which helps a lot. But like most people, I’m busy and can’t cook everything from scratch —especially beans. Canned beans tend to be high in sodium, but they are such a convenience. Is the sodium still that high when they are rinsed and drained?

—O.E., Concord, California

DEAR O.E.: It is good that you are avoiding excess sodium, given that hypertension (high blood pressure) runs in your family. Always keep in mind that the only reliable way to determine whether your blood pressure is elevated is to have it checked regularly. If ordered by your doctor, your insurance may cover an athome unit.

Regarding your question, low-salt and no-salt-added varieties of canned vegetables are now widely available. If you don’t see them at your local grocery, ask the manager about carrying them. A check of the Nutrition Facts panel will reflect the differences in these products and their standard counterparts.

As some of the sodium in the canned liquid clings to the beans, you are correct that draining the contents in a colander, then rinsing well, will significantly cut the sodium content. An examination of this process reported that draining and rinsing reduced sodium by 41%. You can do a taste test before and after your drain-and-rinse to note the difference.