Now, saturated dairy fat reduces the risk of a heart attack!
We have been told for decades that, to reduce our risk of a heart attack, we should cut down on saturated fats. And the fat on milk — the cream — is rich in saturated fat. Not surprisingly, more and more people are drinking skim and semi-skim milk, low-fat yogurt and 'light' cheeses.
However, studies over a decade have shown that use of low-fat dairy products increased the risk of prostate cancer in men,[1-4] and ovarian cancer in women.[5,6] So you won't be surprised that these cancers have increased in number since 'healthy eating' was introduced in the 1980s.
Now, a new study published in the prestigious American Journal of Clinical Nutrition, shows that, far from increasing the risk of heart attack, drinking dairy fat actually reduces the risk![7]
Not only that, but the researchers found that drinking full-cream milk and eating other full-fat dairy products also reduced the risk factors for the metabolic syndrome — a collection of conditions which includes obesity and diabetes.
The usual way studies like this are conducted is to get the participants to fill in a questionnaire. From these the researchers try to assess how much of each nutrient people are eating. It's a highly inaccurate protocol. The reseachers in this latest study took a different approach. Milk fats contain two unusualy fatty acids. Most fatty acids have an even number of carbon atoms, but milk fats have two saturated fatty acids with an odd number of carbons: pentadecanoic acid with 15 (15:0) and and heptadecanoic acid with 17 carbons (17:0). To assess the participants' intakes of milk fats, they measured levels of these two fatty acids. It is a much more reliable measure of dairy fat intake.
There was a reduction in heart attack risk in both men and women, as intakes of milk fats increased. However, the reduction in risk only reached statistical significance in women.
This study adds weight to other recent reviews which have shown that the idea that saturated fats are harmful is seriously flawed.
What is becoming clear is that giving up the pleasures of drinking full-cream milk is not the best way to maintain a healthy life. Not only is there no need to give up cream, butter, real Greek yogurt and full-fat cheeses, drinking skim milk can seriously damage your health.
References
1. Chan JM, et al. Dairy products, calcium, and prostate cancer risk in the Physicians' Health Study. Am J Clin Nutr 2001; 74: 549-554.
2. Tseng M, et al. Dairy, calcium, and vitamin D intakes and prostate cancer risk in the National Health and Nutrition Examination Epidemiologic Follow-up Study cohort. Am J Clin Nutr 2005; 81: 1147-1154.
3. Veierod MB, et al. Dietary fat intake and risk of prostate cancer: a prospective study of 25,708 Norwegian men. Int J Cancer 1997; 73: 634-638.
4. Grant WB. An ecologic study of dietary links to prostate cancer. Altern Med Rev 1999; 4: 162-169.
5. Kushi LH, et al. Prospective study of diet and ovarian cancer. Am J Epidemiol 1999; 149: 21-31.
6. Fairfield KM, et al. A prospective study of dietary lactose and ovarian cancer. Int J Cancer 2004; 110: 271-277.
7. Warensjö E, Jansson J-H, Cederholm T, et al.
Biomarkers of milk fat and the risk of myocardial infarction in
men and women: a prospective, matched case-control study. 19
May 2010 [epub ahead of print publication as Am J Clin Nutr
doi: 10. 3945/ajcn.2009.29054]
