What’s the deal with “fat”?
The “fat” controversy has been rampant in the nutrition world for years. For those of us who choose to consume dairy as part of our diet, we’re faced with the decision to purchase non-fat, low-fat, moderate or high-fat products. So what does the research tell us about what type of dairy is best?
The truth is, there is little research in the area of whole milk or high-fat dairy products and what’s out there is often contradictory. However, the old school of thought which recommended non-fat or low-fat dairy has been recently challenged after several studies have found high-fat may offer protective effects compared to low-fat counterparts.
Here’s the convincing evidence:
A 2013 meta-analysis of 16 observational studies concluded that there was not enough evidence to support the hypothesis that high-fat dairy foods contribute to obesity and heart disease. In fact, the reviewers found the opposite was true in that high-fat dairy was associated with a lower risk of obesity.
In another recent cohort study that spanned 12 years, researchers found that middle-aged men who consumed high-fat milk, butter, and cream had a significantly lower risk of developing central obesity than those who followed a meal pattern that included low fat dairy. The same was found for women middle-aged women in a 2016 study that found consumption of high fat dairy was associated with reduced risk of becoming overweight over an 11 year follow-up.
Studies are not only looking at the effects of dairy fat on weight, but also the risk of diabetes. A 2016 study that spanned 15 years of follow-up found that higher dairy fat concentrations were associated with lower risk of developing diabetes.
And when it comes to saturated fats, relatively high in full-fat dairy and long thought to be a major contributor of cardiovascular disease, perhaps not all are created equal. The most recent report from the Dietary Guidelines Advisory Committee states that more research needs to be done on the effects of saturated fat as different sources contain different fatty acid profiles which may have varying effects on our metabolism. There is currently no consensus from studies on whether cardiovascular risks are lowered with a diet inclusive of low-fat dairy. In a Multi-Ethnic Study of Atherosclerosis, saturated fatty acids that were found in meat were associated with a higher risk of cardiovascular disease while dairy was associated with a lower risk.
Of course, there may be other considerations when it comes to the fat content in our dairy foods. A well-known study published in 2007 from the Nurses’ Health Study found that intake of high-fat dairy may be associated with a decreased risk of anovulatory infertility, suspected to be associated with levels of estrogen and progesterone, which are removed during the process of making fat-free products. (For more information on this, be sure to jump on over to my full review here with 20 fertility fueling dairy recipes for females!)
So what’s the deal?
While there’s no clear explanation of how high-fat dairy and its associated benefits, it may be due to increased satiety (feeling fuller) from fat as well as slowing the absorption of sugars found in dairy. As a result, we end up eating less and are better able to stabilize blood sugar. Another hypothesis is that the processing involved in removing fat from dairy products also removes important bioactive content of whole milk and other high-fat dairy products. These substances may positively impact our metabolism in a way that helps to utilize the fat rather than store it.
Stay tuned. Research doesn’t clearly point us one way or the other but emerging evidence suggests the higher fat dairy we have been avoiding for years is likely not as bad as we once thought. And if you haven’t tried whole fat dairy, you’re in for a treat.