A Swedish study of more than 106,000 men and women shows that both drinking milk and restricting fruits and vegetables are associated with increased risk for premature death (Am J Epidemiol, Feb 2017;185(5):345-361):
• Women who drank three or more glasses of milk and ate fewer than two fruits or vegetables a day were three times more likely to die than those who drank fewer than two glasses of milk per day and ate fruits and vegetables at least five times per day.
• Women who drank three glasses of milk per day and ate fruits and vegetables at least five times per day still had a 60 percent higher risk of early death compared to women who consumed the same amount of fruits and vegetables but drank little or no milk.
• Men who drank three or more glasses of milk per day were 30 percent more likely to die than men who did not drink milk.
Previous studies have shown increased association between milk and premature death and increased bone fracture risk (British Medical Journal, October 28, 2014; 349:g6015), but this is the first study to show that drinking milk harms women more than men. The authors speculate that women have more estrogen, which changes the way their bodies react to the milk sugar, galactose.
How Milk May Increase Risk for Heart Attacks and Diabetes
Milk is a high-sugar drink. We know that D-galactose, a sugar found in milk, causes the same oxidative damage and chronic inflammation that is associated with diabetes, heart attacks, certain cancers and bone loss (Biogerontology, 2004;5:317-25). The people who drank milk had increased urine levels of 8-iso-PGF2a (a biomarker of oxidative stress) and serum interleukin 6 (a major inflammatory biomarker). Chronic exposure of mice, rats and Drosophila flies to galactose caused their cells to develop signs associated with aging: shorter telomeres and DNA damage (Journal of Neuroscience Research, 2006;84(3):647-654).
Cheese and Yogurt Appear to Help Prevent Heart Attacks and Diabetes
Fermentation, used to create yogurt or cheese from milk, breaks down the galactose, which explains why fermented dairy products may help to prevent heart attacks (Journal of Agricultural and Food Chemistry, April 2015;63 (10):2830-9). People who ate a lot of cheese had very high levels of butyrate in their stool and urine and much lower blood levels of the bad LDL cholesterol. This means that the fermented dairy products are being converted by bacteria in the intestines to butyrate that prevents food from forming the bad LDL cholesterol that is associated with increased heart attack risk. The authors believe that they have shown that fermented dairy products encourage the growth of healthful intestinal bacteria that may help to prevent heart attacks. Another study of 27,000 people, ages 45 to 74, showed that eating cheese and yogurt lowered risk of type-2 diabetes by 25 percent (Am J Clin Nutr, April 2015).
Cheese May Explain the “French Paradox”
For more than 50 years, the medical community has speculated that the “French Paradox” — why people in southern France have a low rate of heart attacks — might be explained by the fact that they drink a lot of wine. Several recent studies have questioned whether alcohol in any form offers any protection from heart attacks. Taking more than two drinks a day and binge drinking have both been shown to increase risk for heart attacks and heart failure (Journal of Cardiopulmonary Rehabilitation & Prevention, May/June 2014;34(3):159-171). I think that instead of wine, cheese may be the explanation; the traditional French diet includes plenty of cheese and very little milk.
All Sugared Drinks Can Harm
Sugared drinks are associated with increased risk for obesity, diabetes, inflammatory-related pain, heart attacks, certain cancers and premature death. Eating or drinking sugar can cause a high rise in blood sugar that can damage all of the cells in your body. Sugar in drinks causes a much higher rise in blood sugar levels than sugar in food. When food reaches your stomach, the pyloric sphincter muscle at the end of the stomach closes and only a liquid soup is allowed to pass into your intestines. Beverages pass very quickly into your intestines and then into your bloodstream, while solid foods stay a long time in your stomach. An 8-ounce glass of milk contains:
• 122 calories, more than an 8-ounce glass of soda
• more than three teaspoons of sugar
• more than the current daily recommendations for sugar for children. Chocolate milk and other milk-based beverages often have even more sugar added to make them taste better.
Yogurt and other fermented dairy products do not need to be classified as sugared drinks because the fermentation process breaks down galactose (the main sugar in the milk from which they are made). However, check the labels to make sure that other sugars have not been added.
Recent research shows that the high content of the sugar, galactose, in milk, and not the cholesterol or saturated fats, may be harmful to your health. We do not know if milk causes diabetes or heart attacks, or whether cheese and yogurt help to prevent them. However, recent studies suggest that you may want to limit the amount of milk that you drink, and that cheese and yogurt may be healthful.