Health professionals and nutritionists have been telling people for decades that full-fat milk and cheese (as well as other dairy products such as yogurt) are bad for the heart. They were sure that the saturated fat in such products would clog coronary arteries. Many people listened to their warnings and started drinking skim milk and eating low-fat yogurt and cheese instead. How well does the evidence support that shift?
Do Full-Fat Milk and Cheese Raise Cholesterol?
Scientists thought that full-fat dairy products, which are high in cholesterol, would raise cholesterol levels in the blood. This, they assumed, would lead to atherosclerosis and heart disease.
Does sticking with low-fat dairy lower cholesterol levels? A randomized controlled trial recruited 72 individuals with metabolic syndrome (American Journal of Clinical Nutrition, Sept. 2021). This condition is defined as elevated blood sugar, high blood pressure, a big belly and abnormal levels of cholesterol and triglycerides. Metabolic syndrome puts people at risk for cardiovascular disease.
Researchers assigned the volunteers to a diet containing less than three weekly servings of milk or three servings daily of either full-fat or low-fat milk, yogurt and cheese. After three months, there were no differences in LDL, HDL or total cholesterol. Triglycerides and free fatty acids were also unaffected.
The scientists conclude,
“Therefore, dairy fat, when consumed as part of complex whole foods, does not adversely impact these classic CVD risk factors.”
Grandparents Ignored Advice to Avoid Full-Fat Dairy Products:
Q. All my grandparents and my father were born in Europe. They dismissed the American scientists’ advice to avoid fat. Instead, they enjoyed nuts and full-fat dairy products. My father took cream in his coffee without guilt. They all lived well into their 80s, working in their gardens to the end. How did they live so long eating eggs and cheese?
A. The American Heart Association has been promoting a low-fat diet for decades. At one time, it also recommended limiting egg consumption to no more than three a week. Its recent guidelines stress an overall dietary pattern with plenty of vegetables, fruits and whole grains, such as a DASH or Mediterranean diet, and allows an egg or two a day.
The initial limits on eggs seem to have been based on the assumption that eating egg yolks, which are high in cholesterol, would increase blood cholesterol. That does not appear to be true (Current Atherosclerosis Reports, July 2023). Moreover, a diet containing full-fat dairy products does not seem to raise cholesterol more than one with low-fat dairy.
A recent review notes,
“A body of observational and clinical evidence indicates, however, that whole-milk dairy food consumption, despite saturated fat content, does not increase the risk for cardiovascular disease” (Advances in Nutrition, Nov. 2023).
There is growing evidence that ultra processed foods that are high in sugar and salt may be more harmful to cardiovascular health.
How Do Full-Fat Milk and Cheese Affect the Risk of Heart Disease?
A meta-analysis published in the European Journal of Epidemiology suggested even earlier that the advice to avoid full-fat milk and cheese may have been misguided. The authors analyzed data from 29 studies over more than two decades (European Journal of Epidemiology, Apr., 2017). Nearly one million subjects participated in these trials.
No Link Between Full-Fat Dairy Products and Death from Heart Disease:
The investigators could find no link between the consumption of milk or dairy products and heart disease or death. It didn’t matter whether people consumed high- or low-fat dairy products. There was no increase in mortality.
The investigators even detected a slight trend towards a lower risk of heart attacks or strokes among people who consumed fermented dairy products such as kefir, yogurt, sour cream and cheese. At this point, we should reconsider admonitions to avoid dairy products high in saturated fat.
This is not the first study to show that people who eat butter, cheese or other full-fat dairy products live just as long as those who go the low-fat route. Research published in 2016 under the title “Is Butter Back?” showed no link between butter consumption and heart disease. We doubt that the current study on the effect of full-fat milk and cheese on blood lipids will be the last one, either.
Is There a Link Between Dairy Products and Diabetes?
A study in the journal Circulation suggested that full-fat dairy products may actually be beneficial, especially for preventing type 2 diabetes (Circulation, online March 22, 2016 ). In this study, data from 3,333 adults between the ages of 30 and 75 were analyzed between 1989 and 2010.
The participants were part of the Nurses’ Health Study and the Health Professionals Follow-Up Study. None had diabetes at the start of the trial. Blood samples were collected at the beginning of the research and again four years later.
Who Was Less Likely to Be Diagnosed with Diabetes?
Although these participants are queried every two years about their diets, exercise and other lifestyle factors, the investigators did not rely solely on these reports. They also took blood samples and looked for markers that people were consuming full-fat dairy products rather than the skim or low-fat versions.
The volunteers whose blood fats indicated they were consuming full-fat dairy products were 50 percent less likely to develop diabetes during the 20-year follow-up period. These data add to the growing recognition that saturated fat in dairy products may be helpful rather than harmful.
