A recent Danish study followed 54,903 healthy men and women, 50-64 years old, for 16 years. Those who ate primarily fermented dairy products such as cheese and yogurt were significantly less likely to suffer heart attacks than those who drank milk (The Journal of Nutrition, January 9, 2020). It made no difference whether the milk was whole or reduced fat.
Fermented dairy products were also associated with reduced risk for heart attacks in Australians (Journal of Nutrition, Oct 2019;149(10):1797-1804) and Finns (British Journal of Nutrition, Oct 29, 2018). A review of 15 prospective studies showed that fermented dairy products were associated with reduced heart attack risk (Eur J Nutr, Dec 2017;56(8):2565-2575), and other studies showed reduced levels of inflammation (Br J Nutr, Apr 2015;113 Suppl 2:S131-5) and LDL cholesterol (Am J Clin Nutr, 2000 Mar;71(3):674-81).
Galactose, the Inflammatory Sugar in Milk
Milk is a high-sugar drink and sugared drinks are associated with increased risk for heart attacks, obesity, diabetes, and premature death (Circulation, March 18, 2019). Milk and other unfermented dairy products are full of the sugar, galactose, that is one of the four pro-inflammatory sugars that can pass from the intestines into the bloodstream — glucose, fructose, mannose and galactose (Cytokine, Sept 2014;69(1):150-153). Inflammation means that your immune system is overactive. When you are infected by germs, your immune cells and proteins try to kill the invading germs, but as soon as the attacking germs are gone, your immune system is supposed to dampen down. If it stays active, it can use the same cells and proteins to attack you and damage your own cells, including the cells that line your arteries.
Fermented dairy products (such as yogurt, kefir, quark, and many cheeses) are made by adding live bacteria that “eat” the galactose and break it down. Milk, butter and cream contain large amounts of galactose, while aged cheeses and yogurt made from these products contain very low amounts of galactose because it has been destroyed in the fermentation process (Nutrition, Metabolism and Cardiovascular Diseases, May 21, 2018). Cheese and yogurt (with no added sugars) lower high blood sugar and insulin and are not associated with increased risk for heart attacks or diabetes (Nutr Rev, 2015;73(5):259-275) or gaining weight (BMC Med, 2014;12:215).
These studies do not prove that milk causes heart attacks or diabetes, or that cheese and yogurt help to prevent them. They suggest that you should limit the amount of milk that you drink, and that cheese, yogurt and other fermented dairy products may be more healthful choices.
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