MILK IS NOT ESSENTIAL TO MAKE BONES STRONGER IN ADULTS - STUDY FINDS

Maryam Adegboyega
2 days ago
2 min read

New evidence suggests that milk alone may not significantly strengthen bones or reduce fracture risk in adults, challenging long-held beliefs about dairy and calcium.

For decades, “Strong Bones” has been the dairy industry’s best-known advertising campaign because milk is high in calcium. A cup of milk contains about 300 mg of calcium, but scientists have noted that this calcium content does not automatically produce stronger bones or fewer fractures.

In agreement, Walter Willett, a Harvard professor of epidemiology and nutrition, mentioned in an interview with The New York Times that the claim that milk prevents fractures is not fully supported by the research. Estimates of calcium bioavailability from milk are commonly cited near 30%, which would mean that roughly 90 mg is absorbed from a 300 mg serving, and absorption varies by study and individual factors.

Clinical trials and randomized studies more consistently show that milk or dairy intake can improve bone mineral density (BMD), which is strongly linked to height. This was confirmed in a study that showed that milk consumption, particularly between ages 12-18, is linked to taller statures in adulthood. Research in fact shows that a taller stature is one of the greatest risks of bone fractures.

Unlike in childhood, the benefits of drinking milk for bone health is still unclear for adults. In a review published in the New England Journal of Medicine, researchers showed that countries with lower milk consumption, such as Indonesia, South Korea and Japan, had a lower incidence of hip fractures compared to countries with high milk consumption. The study also raises concerns around the risks of high consumption of milk in adults, including prostate and endometrial cancer.

Some observational studies and recent reviews have reported that fermented dairy products (for example, yoghurt or kefir) show more favourable associations with bone markers or lower fracture risk than plain milk in certain analyses. These results were not linked to high calcium contents but rather the probiotics present in these foods. Some studies have suggested that probiotics can help enhance calcium bioavailability and absorption and promote bone health by reducing inflammation that can damage the bones. However, the evidence of fermented dairy on stronger bones is inconsistent and more evidence is required.

Overall, milk alone is not the answer to improved bone health; bone strength depends importantly on lifestyle and activity, adequate vitamin D and magnesium status, and other dietary calcium sources such as leafy greens, small bony fish (e.g., sardines), tofu, and fortified beverages.

Sources