Report from the LI Conference, part 15

Scientists are nothing is not methodical. After examining the consequences of dairy avoidance in children, you couldn't have found a sports book in all Las Vegas that would be willing to take money against what the next panel would be.

Consequences of Excluding Dairy or of Avoiding Milk in Adults
Robert P. Heaney, M.D., FACP, FACN
John A. Creighton University Professor
Osteoporosis Research Center
Professor of Medicine
School of Medicine
Creighton University

To no one's surprise, Dr. Heaney found that adults who think they have lactose intolerance tend to avoid dairy. And in fact, studies have found anywhere from 33% to 80% lower calcium intake in lactose intolerant populations.

Part of his talk did differ from expectations. In what should also be to no one's surprise, taking a properly close look at the nuances give a picture of reality at odds with conventional wisdom.

But it is an oversimplification to focus exclusively on single nutrients, even calcium. Nutrients are not drugs, and they do not act in a vacuum. Rather, like the instruments in a symphony orchestra, they produce their effects in concert with one another. A striking example of this mutual dependence is seen in the interaction of calcium and protein in the diet. Until recently, high protein intakes were considered to be potentially harmful for bone because of their effect on urinary calcium excretion. Increased calciuria was clearly demonstrated for protein and for pure amino acids, whether taken orally or intravenously. However, when protein was fed as a food, strangely there was no effect on calcium balance. More recently, it has become clear that calcium and protein, rather than antagonists, are actually synergistic in their skeletal effects. In postmenopausal women with low protein intakes, increasing calcium intake can slow bone loss, but not much more. By contrast, with high protein intakes, added calcium leads to actual bone gain. This is an important consideration in our context because individuals with low dairy intakes are missing not only the calcium but also a rich source of dietary protein, which is as necessary for bone rebuilding as is the calcium that is the more obvious component of bony material.

In brief, dairy supplies a broad spectrum of nutrients that work together better than gaining them individually or from foods less gifted. Even calcium-fortified orange juice isn't anywhere as good a source as dairy.

And here's a tidbit that will infuriate those who cherry-pick the medical journals for anti-milk reports.

While the focus of this session is predominantly on skeletal effects, it should be stressed that inadequate dairy intake has multiple other consequences as well, including increased risk of metabolic syndrome, hypertension, preeclampsia, obesity, and certain forms of cancer, particularly colon cancer. Thus milk avoidance is, for most adults, a risky behavior.

Reality is a harsh mistress.