The Skinny on Dairy Fat
Whole or full-fat dairy is actually a topic I want to cover in a lot of detail. I personally feel that this is a grossly misunderstood topic, and I want to clarify several things here.
There is actually a good amount of research, in several populations, that shows that full-fat dairy consumption is associated with lower BMI, lower waist circumference, and lower risk of cardiovascular disease (especially stroke). Yes, you read that right: whole fat dairy is associated with a decreased risk of CVD, especially stroke. Low-fat or fat-free dairy is actually often associated with increased BMI and waist circumference (though to be fair this is not always the case).
In fact Dr. Ronald Krauss, one the worlds leading lipid researchers, showed that while saturated fat from dairy does raise LDL, it is an increase in large, fluffy and benign LDL not the small, dense and atherogenic LDL.
Whole fat dairy from grass-fed cows contains a boatload of powerful vitamins and healthful fatty acids. These vitamins are fat-soluble, meaning they are bonded to the fatty acids in the dairy, and are therefore nearly non-existent in fat-free dairy, same for the fatty acids obviously. The fat is where vitamins A, D, E and K2 are, as well as conjugated linoleic acid (CLA), butyric acid, omega-3 fatty acids, trans-palmitoleate and medium chain triglycerides. Low-fat and fat-free dairy are woefully lacking in these properties.
CLA is present in human body fat in proportion to dietary intake, and has been shown to be a powerful ally in the fight against cancer. Meat and dairy from grass-fed animals provide the richest source of CLA on the planet, containing three to five times more CLA than feedlot-raised animals. CLA has been found to greatly reduce tumor growth in animals, and possibly in humans as well. In a Finnish study, women who had the highest levels of CLA in their diet had a 60% lower risk of breast cancer than those with the lowest levels. Simply switching from conventionally-raised grain-fed meat and dairy to pasture-raised grass-fed versions would have placed all the women in the lowest risk category.
In addition, CLA may also help to fight against heart disease. In a study of 3626 Costa Rican men and women (a country that uses traditional pasture-grazing for dairy cows), people with the highest level of CLA in their body fat were 49% less likely to have had a heart attack, compared to those with the lowest level. This may be due to CLA intake and tissue levels being associated with greater amounts of large and fluffy LDL, and inversely associated with small and dense LDL.
Vitamin D is pretty much the best thing since sliced bread, and getting some from food is always a good thing. Low blood levels of vitamin D are associated with lowered immunity, increased risk of 17 cancers (and counting), increased risk of heart disease, neurological and psychological disorders (including ADD and depression), diabetes, stroke, hypertension, bone loss, and loss of muscle mass and strength as we age and more.
Omega-3s are absolutely amazing, as they may improve nerve, brain, eye, heart and cardiovascular function as well as decreasing inflammation, joint pain, arthritis, psychological disorders, and risk of breast cancer and heart disease all while improving mood and body composition!
Medium chain triglycerides are unique fatty acids that are more readily utilized as fuel rather than stored as energy, as well as particular ones, like lauric acid, containing anti-viral and anti-microbial properties.
Vitamins A and E are powerful antioxidants.
Butryric acid may help with bodyweight regulation, and is a primary fuel source for our intestinal flora.
Notice that I didnt mention vitamin K2 yet? That is because I was saving what might be the best for last. Several studies have found that a higher vitamin K2 intake is associated with a lower risk of heart attack, ischemic stroke, cancer incidence, cancer mortality and overall mortality. Men with the highest vitamin K2 consumption had a 51% lower risk of heart attack mortality and a 26% lower risk of all cause mortality compared to men consuming the lowest amount!
One of the ways vitamin K2 improves cardiovascular health is its ability to prevent and decrease arterial calcification by 30-40%. And, this only speaks to vitamin K2s effects of cardiovascular health; it is also crucially important for proper fetal development and bone health, to name a few additional benefits.
What about Dairy and Diabetes?
With little fanfare, a study recently came out by Dr. Dariush Mozaffarian and colleagues. Why so little fanfare, you ask? Because the study suggests that dairy fat may actually protect against diabetes, and that goes against conventional wisdom and government recommendations.
Dr. Mozaffarian and company collected two measures of dairy fat intake in 3,736 Americans. They took six 24-hour dietary recall questionnaires, as well as taking blood levels of trans-palmitoleate. Trans-palmitoleate comes almost exclusively dairy fat and red meat fat, and therefore it reflects the intakes of these foods. Dairy provided most of the trans-palmitoleate fatty acid in this study.
Adjustments were made for confounding factors, and trans-palmitoleate levels were associated with a smaller waist circumference, higher HDL cholesterol, lower serum triglycerides, lower C-reactive protein, lower fasting insulin and lower calculated insulin resistance. In addition to that awesome data, people who had the highest levels of trans-palmitoleate had 1/3 the risk of developing diabetes over the 3 year study period.
Again, it is important to note that trans-palmitoleate is a fatty acid, and so is only significant from whole fat dairy, not from low-fat or fat-free. The investigators also noted that greater whole-fat dairy consumption was associated with lower risk for diabetes. This is an important distinction as it wasnt just trans-palmitoleate levels that were associated with the decreased risk, but the actual consumption of the food that provides that element was as well.
Heres another nice quote from the authors: Our findings support potential metabolic benefits of dairy consumption and suggest that trans-palmitoleate may mediate these effects. They also suggest that efforts to promote exclusive consumption of low-fat and nonfat dairy products, which would lower population exposure to trans-palmitoleate, may be premature until the mediators of the health effects of dairy consumption are better established.
While it is certainly possible that trans-palmitoleate is mediating a lot of these positive health outcomes that were associated with it, in all reality it only makes up a tiny fraction of the fat content of milk. I tend to believe that instead it is more of a marker of dairy fat intake, with the benefits more likely coming from the other elements contained in dairy fat CLA, vitamin K2, butyric acid, vitamin D, etc.
Stay tuned for part 3!