Book Review: "The Calcium Key"

Friday, December 15, 2006 - 9:25am

By Katie Clark, MPH, RD

Examining The Connections Between Calcium & Weight Loss

The self-proclaimed “discoverer” of the calcium-weight loss connection, Michael Zemel, author of The Calcium Key, claims that research links dairy and weight loss. What’s the truth behind this recent diet fad?

Fatally flawed research
The premise of The Calcium Key and its associated diet is the “scientifically-proven” connection between increased dairy intake and weight loss. However, conclusions are based on animal studies or a limited number of human studies with small sample sizes derived largely from within Zemel’s body of research.

Zemel does not dispute the claim that he is almost entirely funded by the dairy industry—an industry that has an agenda, which is to increase your consumption of milk-based foods. He has received over $2 million from the dairy industry and is the sole researcher pushing the idea that dairy foods help you lose weight.

Weight loss: It’s not all dairy’s doing
In the book, Zemel does provide a good explanation of calcium’s role in the body. However, there’s a dearth of scientific explanation as to why calcium alone causes weight loss, and particularly how it decreases abdominal fat.

Zemel advocates cutting maintenance calorie levels by 500 calories a day, while maintaining 3-4 low-fat dairy servings. Essentially, these guidelines create a calorie deficit. Hence, dieters following this plan may be losing weight because they’re eating less and cutting calories. This is the same mechanism that occurs with many other fad diets. When people learn to pay attention to their eating habits and make healthy adjustments, they lose weight.

On a positive note, the book includes some ingenious recipes. It also mentions the relationship between exercise and weight loss. There’s even a small contribution by a registered dietitian. However, many of the dietary suggestions in The Calcium Key mirror those of the American Diabetes Association, as well as other well-established dietary guidelines. The book does not contain conclusive evidence linking calcium and dairy’s role in weight loss.

The bottom line
Save your money. Cutting calories and increasing your exercise is the most surefire way to lose weight. The research linking dairy with weight loss is still in its initial (and questionable) phases. While adequate calcium intake is essential for your health, it isn’t entirely convincing that you must eat dairy to lose weight.