Dairy is indeed a source of calcium, a nutrient required for bone health, but there is no scientific evidence that consuming dairy improves bone health or prevents osteoporosis. Some studies even suggest the opposite. Countries that consume the most dairy milk actually have some of the highest rates of bone fractures. What is more important for bone health is regular weight-bearing exercise, vitamin D and all the nutrients, including calcium, obtained from eating plenty of fruit and vegetables.
Parents often worry that dairy is required for normal growth and development in childhood. But when you consider that more than 70% of the world’s population are in fact lactose intolerant after weaning, the inclusion of dairy for most children will result in distressing abdominal symptoms. In fact, dairy consumption is linked to the development of eczema, asthma and acne, conditions that negatively impact a child’s quality of life. Even though children that include dairy in the diet may grow to be taller, this may actually be a disadvantage as greater height increases the risk of developing cancer.
When you consider that the purpose of mammal’s milk is to promote rapid growth of their young, it won’t surprise you to learn that milk is high in growth factors such as insulin-like growth factor. In addition, dairy cows are kept pregnancy whilst being milked, so the milk is high in female hormones such as oestrogen. These growth factors and hormones are a concern for the development of cancers in humans, with the strongest evidence supporting dairy consumption as a significant risk factor for prostate cancer in men. Although the association in not as strong for females cancers, there is genuine concern that dairy consumption may increase the risk of endometrial, breast and ovarian cancers.
There are better choices we can make. Replacing cow’s dairy for soya milk and foods can reduce the risk of breast cancer. For example, regular consumption of tofu can reduce the risk of breast cancer by around 22% when comparing those who eat the most versus those that eat the least. Swapping dairy milk for soya milk could reduce the risk by up to 32%. Consuming soya in childhood and adolescence can even reduce the risk of developing breast cancer later in life. Similar findings are true for prostate cancer. Soya milk and foods are associated with a lower risk. Fortified soya and pea milks have the same amount of protein and calcium as cow’s milk without the saturated fat and health risks associated with dairy consumption. Health Canada’s 2019 dietary guidelines recognise that dairy is not essential in the diet and have removed it as a food group.
The addition of milk and other dairy products to an otherwise healthy plant-based diet centred around fruits, vegetables, whole grains, beans, nuts and seeds has no discernible benefits and may even cause harm. When the ethical and environmental considerations are taken into account, this leaves no doubt that dairy is best left off the plate.
For more information about vegan sources of calcium, check out this article by Lisa Simon, Registered Dietitian at Plant Based Health Online.
By Dr Shireen Kassam, Co-founder of Plant Based Health Online