Are alarm bells about whole milk much ado about nothing?

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On Nutrition

When the congressional Committee on Education and the Workforce voted last month to advance the Whole Milk for Healthy Kids Act of 2023, a bill that would allow schools to offer whole milk to students, there was much hand-wringing. Would this increase saturated fat in kids’ diets, setting them on a path to heart disease? Would this — gasp — make kids fat? (I use fat as a neutral descriptor, like tall or brown-eyed.) Let’s see what current nutrition science has to say.

National dietary guidelines and many health experts recommend avoiding whole milk and other forms of full-fat dairy to help meet the broader recommendation to limit saturated fat intake to 10% of calories. However, while about 70% of the fats in whole milk are saturated — with 25% monounsaturated and 2.3% polyunsaturated — there are hundreds of different types of fat in milk, including many we don’t get much of from other foods. Some may have beneficial effects, either alone or together. Plus, milk is a source of calcium, potassium and vitamin D, which many Americans don’t get enough of.  

For decades, much nutrition advice was based on specific nutrients rather than on foods themselves. This ignores how a food’s many nutrients interact together — as with other whole foods, milk is a complex matrix of vitamins, minerals, proteins, carbohydrates and fats. It now appears that part of the controversy and inconclusiveness about the role of saturated fat in health and disease is because the type of saturated fat and the other qualities of the food it’s packaged in matter.

Fortunately, researchers have started to look more closely at whole foods rather than isolated nutrients. For example, the Multi-Ethnic Study of Atherosclerosis (MESA) found that saturated fats from meat were associated with higher risk of developing cardiovascular disease, while dairy fat was associated with a lower risk. The authors concluded that something about dairy foods may minimize the general association between saturated fat intake and cardiovascular disease risk.

A 2023 systematic review found there is little robust evidence that a higher dairy intake — including full-fat dairy — increases blood pressure or cholesterol, and some studies are finding that whole milk might have more benefits than low or nonfat milk. For example, a study published in May found that whole and low-fat milk reduced the risk of high blood pressure, while skim milk increased the risk. A small 2021 randomized controlled trial found that in men and women with metabolic syndrome, a diet rich in full-fat dairy had no effects on blood pressure or cholesterol and triglyceride levels compared with diets with little dairy or those rich in low-fat dairy. 

Let’s circle back to the Sturm und Drang about whole milk making kids gain weight — a main reason behind long-standing recommendations that children stop drinking whole milk at age 2. A 2020 systematic review and meta-analysis found that drinking whole milk is associated with a lower likelihood of kids having a BMI in the “obese” range, perhaps because whole milk is more satisfying. Another 2020 systematic review had similar findings, concluding “the limited literature in this field is not consistent with dietary guidelines recommending that children consume preferably reduced-fat dairy products.” 

Along those lines, in a 2020 narrative review for the New England Journal of Medicine, Walter Willett and David Ludwig of the Harvard T.H. Chan School of Public Health concluded that “no clear benefit of consuming reduced-fat dairy over whole dairy products has been established” and that guidelines should “de-emphasize reduced-fat milk as preferable to whole milk.”


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