In the comment section of a previous post, Mark from Calorie Lab offers a helpful link to a new study on dairy weight loss, which fails to support the dairy weight loss claims. Still, Mark has doubts about the harmfulness of dairy weight loss messages: "[G]iven that dairy is a good source of calcium, and is not soda pop, why not just let it ride and go on to more important battles?."
I give great weight to the importance of clear government communication about the best science on diet, nutrition, and healthy weight. When more burdensome regulatory policies seem unwise or politically infeasible, clear communication stands out as a key arena for good policy. At the very least, the government should not directly sponsor unhealthy consumer messages.
Why are dairy weight loss messages -- especially for high-fat dairy products -- unhealthy? First, there is the problem of fad diets. I'll quote the Federal Trade Commission's report written by Harvard scientist George Blackburn: “By promoting unrealistic expectations and false hopes, [fad diets] doom current weight loss efforts to failure, and make future attempts less likely to succeed” (Blackburn, 2002). Second, fat is more calorically dense than other foods: it has 9 calories per gram, whereas protein and carbohydrates have 4 calories per gram. Third, the saturated fat in high-fat dairy products contributes to heart disease. After all, weight loss is not the only measure of good health.
There is nothing wrong with promoting skim milk and lowfat yogurt. Most cheese is high-fat, but if there were product or advertising innovations that developed a market for low-fat cheese, that would be fine also. Indeed, I think it would be sound policy for the checkoff programs to promote any messages consistent with the Dietary Guidelines. If promoting low-fat dairy received a large fraction of milk and dairy board spending, I would support these boards myself. But these federally sponsored messages spend most of their $200 million plus dollars per year to support high-fat dairy products with misleading health claims. Federally sponsored advertising on this scale swamps healthier messages. We shouldn't just ignore it and "let it ride."
[Update later that morning: See also the curious report by Kate at Accidental Hedonist. Dairy Management Inc. (DMI) is the operating arm of the federally sponsored dairy checkoff program, and it incorporates other previously independent organizations such as the National Dairy Council. There is more information than I can immediately process, including budget information, about this web of organizations in the USDA report to Congress released this week.]