Drinking three or more glasses of milk per day may be harmful to women’s health, a study suggests.Women in the study who drank at least three glasses of milk a day were nearly twice as likely to die over the next 20 years compared with their peers who drank less than a glass daily, researchers in Sweden found. In addition, the study, published in the British Medical Journal found that women’s risk of bone fracture climbed steadily as their milk intake increased.
The reason could be galactose, a simple sugar found in milk, said Karl Michaelsson, a professor at Uppsala University in Sweden and one of the study’s authors. “That compound might induce oxidative stress and low-grade inflammation, and that type of inflammation can affect mortality and fractures,” Michaelsson said.
Many health bodies recommend that adults get the equivalent of three cups of milk daily, based on the idea that dairy is good for the bones, and may reduce heart disease risk. But there’s actually little scientific evidence to support these recommendations, the study authors said.
The study included 61,433 women who were ages 39 to 74 at the study’s start, and 45,339 men ages 45 to 79. The women were followed for 20 years, on average. During that time, 15,541 died and 17,252 had fractures, including 4,259 hip fractures. After the researchers took into account factors like age, body mass index and alcohol consumption, they found that women who drank three or more glasses of milk daily were 1.93 times more likely to die during the follow-up period than those who drank less than a glass of milk daily. Among the men, who were followed for an average of 11 years, there was no association between mortality or fractures and milk consumption.
But dairy lovers need not despair. The researchers found that fermented milk products, like cheese and yogurt, which contain little or no galactose, had the opposite effect: women who ate or drank the most fermented milk products were less likely to die or sustain fractures during the study.