A new study reveals dairy products may not protect women’s bones during menopause, when preserving bone mass is most critical. The study, published in the May 2020 issue of The North American Menopause Society’s journal Menopause, shows that during menopause, women who consume dairy products experience neither a slowing of bone loss nor a reduction in the incidence of fractures. The findings run counter to popular opinion that a woman should consume dairy products for bone health later in life.
To determine whether dairy intake was associated with a reduced risk of bone fracture or bone density, the researchers reviewed data from the longitudinal Study of Women’s Health Across the Nation (SWAN), which has tracked the health of more than 3,000 women since 1997.
To do this, they looked at data from 1,955 SWAN participants over a 10-year “menopausal transition” period. They grouped the women into four categories based on total intake of dairy foods, ranging from less than half a serving to greater than 2.5 servings a day, and looked at the incidence of bone fractures and change in lumbar spine and femoral neck bone mineral density. Their analysis showed no significant differences among the four groups.
These results held true across various models and even when researchers controlled for race/ethnicity, age, height, weight, smoking status, physical activity, alcohol consumption, calcium use, menopausal status, and total caloric intake.
“It’s the latest disappointment for the dairy industry, but not surprising, actually,” says Neal Barnard, MD, FACC, president of the Physicians Committee for Responsible Medicine and author of Your Body in Balance: The New Science of Food, Hormones, and Health. “Evidence from many studies has shown that dairy consumption has little or no effect on bone health. The dairy industry made healthy bones its main marketing pitch as a way to promote lifelong milk consumption. But scientific studies have shown that this to be largely a myth.”
Separating fact from fiction regarding dairy foods and bone health is especially important for middle-aged women. During the transition into menopause, women lose bone mineral density at an accelerated rate. This can lead to osteoporosis, a disease characterized by brittle, porous bones that puts sufferers at greater risk of fractures—from falls and even from minor stressors such as bending over or coughing.
“Because two of the greatest risk factors for osteoporosis—age and sex—are beyond a woman’s control, there is an increased focus on possible modifiable risk factors to slow this irreversible, age-related, progressive, degenerative skeletal disease that makes a woman more susceptible to bone fractures,” the North American Menopause Society said in a statement.
NAMS recommends at least 45 minutes of weight-bearing exercise, such as walking, jogging, or climbing stairs, three times each week to keep bones strong.