The Consensus: Milk and Dairy Are Not Bad for Your Bones

Calcium is a mineral that the body needs for many functions, including building and maintaining bones and teeth, blood clotting, the transmission of nerve impulses and the regulation of the heart’s rhythm. About 99 percent of the body’s calcium is stored in the bones and teeth. The remaining 1 percent is found in the blood, muscle and other tissues.

Calcium is an essential nutrient and needs to be obtained in adequate amounts in the diet. Calcium requirements change over the lifespan with the highest amount needed in the critical growing period of adolescence which leads into when a person achieves their peak bones mass in their early 20s (for women) or late 20s (for men). At that point, bones have reached their maximum strength and density. Bone is slowly lost throughout the remainder of life with women experiencing accelerated loss after menopause. Too great a loss of bone mass can lead to osteoporosis.

The link between dairy and bone health

Bone building is a complex process that requires a range of nutrients such as calcium, vitamin D, protein, vitamin K, zinc and B vitamins. Calcium rightly gets a lot of focus for bone health, and dairy foods come up trumps here as they are an excellent source of calcium.

Along with the calcium, dairy foods contain a range of nutrients important for bone health including protein, phosphorus, magnesium and zinc. In developed countries, dairy is a significant contributor to the intake of calcium, protein and other essential nutrients needed for healthy bones.

As Kasper Hettinga from Wageningen University noted most observational studies and randomised controlled trials have shown that higher dairy intake is associated with increased bone mineral accretion during childhood and adolescence and reduced rate of bone loss and reduced risk for fracture in older adults.

Not all studies show the expected relationship between dairy consumption and bone health. This could be because some studies focus on calcium only, whereas milk provides other bone health-related nutrients. It could also be related to not including an important variable next to nutrition for bone health: exercise. In the end, bones only develop well and stay healthy if the right mix of nutrition is combined with sufficient exercise.

Looking at the most recent systematic reviews and meta-analysis, there is a clear favourable benefit of dairy consumption on bone health. A 2018 review published in Nutrition Research Reviewsfound an increase in bone mineral density and a reduction in fracture risk with increasing dairy consumption. An even more recent review and meta-analyses published in Advances in Nutrition in March 2019 found that a healthy diet that included milk and dairy was linked to less chance of having low bone mineral density or of having a fracture. Overall, there is a clear Metafact consensus that dairy is not bad for bones as some people claim.

Some brands of tofu that have been set with calcium, nuts such as almonds and some seeds (such as sesame seeds and tahini) can supply calcium for the person who doesn’t consume dairy. Canned fish with bones can also be a great source of calcium.

Calcium-fortified soy milk is also an excellent substitute for cow’s milk in terms of providing an equivalent amount of calcium. Calcium can also be found in good amounts in plant-based foods such as bok choy, kale, parsley, broccoli and watercress. Then there are supplements that contain both calcium and vitamin D which is a better choice than taking calcium alone.

If you choose to include dairy foods in your diet, then there is nothing to be concerned about that these foods will somehow be bad for your bones. Dairy foods can be a part of any healthy diet as they provide many valuable nutrients that keep bones in good health.