Why some people can’t drink milk

Published on: 14/04/2022

Lactose intolerance explains why some individuals are unable to consume milk. Find out what you can do about it.

Have you ever wondered why some people choose to forgo dairy-based food and beverages for their plant-based counterparts? Besides personal preference, many people do this because their bodies cannot digest dairy products and milk, causing a myriad of symptoms. This condition is known as lactose intolerance.

This condition is in large part due to a deficiency of the enzyme lactase, which is in charge of breaking down the milk carbohydrate lactose. Lactase allows our bodies to break down milk for proper digestion in our gut. In the lactose intolerant, the undigested milk compounds irritate the linings of their intestines, causing symptoms like diarrhea, abdominal pain, bloating, and nausea. Though, symptoms vary for everyone and may also depend on the amount of dairy consumed by the person. Some may trigger mild effects from several glasses of milk, while others may need a visit to the hospital after a few slices of cheese. 

Around 65% of humans become intolerant to lactose (in varying degrees) upon reaching adulthood. This is because lactase is most commonly found in our bodies during infancy when we depend largely on our mothers’ milk for survival, and our dependence rapidly decreases as we age. Out of all human populations, East Asians are the most affected by this, while Northern Europeans are the least affected. This correlates to each cultures’ use of milk products in their cuisine. Very few East Asian foods make use of milk in traditional dishes, while cheeses, creams, and kinds of butter are widely used in Europe. Aside from culture, genetics can also play a role, since people can be lactose intolerant from birth. This is known as congenital lactase deficiency and it makes feeding affected infants a challenging task for doctors. Though, this condition is much rarer.

Lactose intolerance can generally be easy to live with, as many in the world do. There isn’t a treatment for it, so people mostly avoid dairy and milk products to cope with the condition. Lactose-free kinds of milk like soya milk, rice milk, and almond milk are now staples in supermarkets for this reason. These can easily replace cow’s milk in recipes that call for its use. While the tastes are slightly different, people can learn and grow used to them. 

Ever hear the idea that “milk is good for the bones?” This is true, as cow’s milk contains a lot of the mineral calcium, which makes up our bones and teeth. Calcium also plays a heavy role in ensuring our muscles can contract properly. Needless to say, it’s a crucial part of our diets. However, there is little to be worried about if you’re lactose intolerant (or vegan) since many other plant-based foods can be sources of calcium. 

The National Health Service of the United Kingdom recommends the following foods:

  • Tofu
  • Nuts
  • Soya beans
  • Fish
  • Leafy greens

You may not hear about it often, but lactose intolerance affects many around the world. Though, thanks to today’s technology and modernization, alternative products are widely available for consumption. If you or someone you know suffers from this, just know that minor diet changes can go a long way in improving your health and enjoyment of food. It may even expose you to foods you’ve never tried before!


References (APA)

Medline Plus. (2020, Aug 18). Lactose intolerance. Medline Plus. https://medlineplus.gov/genetics/condition/lactose-intolerance/

NHS. (2019). Lactose Intolerance. https://www.nhs.uk/conditions/lactose-intolerance/