What is lactose?
Lactose is a natural sugar found in milk and some milk products. Lactose is broken down in your digestive system by lactase (an enzyme in your small intestine) so that your body can use the lactose for energy.
What is lactose intolerance?
Lactose intolerance is caused by the inability to fully digest lactose. People with lactose intolerance have too little of the lactase enzyme in their small intestine to digest large amounts of lactose at once.
As a result, undigested lactose gets into the large intestine where it’s fermented by your gut bacteria. This can cause symptoms such as gas, bloating and cramps when large amounts of lactose are consumed at once.
Do people with lactose intolerance have to avoid milk completely?
No! The good news is that almost all people with lactose intolerance can still enjoy milk and milk products every day.
A large number of carefully conducted research studies show that people who have medically confirmed lactose intolerance report no symptoms after drinking up to 1 cup (250 mL) of milk at a time, especially when they enjoy the milk with food.
In fact, the National Institutes of Health (NIH) in the United States specifically recommends that people with lactose intolerance not avoid milk and milk products because almost everyone can tolerate some dairy foods, and those who do avoid dairy products are at risk for not getting enough calcium or vitamin D.(1)
Fun fact: The bacteria in fermented dairy products like yogurt, cheese and kefir breaks down some of the lactose, making these foods more easily tolerated by people with lactose intolerance.
7 Tips for Tolerance
If you have been diagnosed with lactose intolerance, you don’t have to deprive yourself of the nutritional goodness that milk products deliver. Try these tips to help you to continue to enjoy the deliciousness of dairy foods.
- Enjoy milk in small portions throughout the day instead of drinking a large glass all at once. If you’ve been avoiding milk, start with small amounts (less than 125 mL) and slowly increase your intake over a few weeks.
- Drink milk with a meal or with other food to slow down digestion.
- Use milk products in recipes.
- Eat yogurt or drink kefir. They have good bacteria that help break down lactose.
- Choose aged cheeses such as Cheddar, Parmesan and Swiss. They have almost no lactose at all!
- Take lactase enzyme drops or tablets before drinking milk.
- Try lactose-free milk products, which are widely available in grocery stores.
Good to know: Milk is more than lactose. A single cup (250 mL) gives you more protein than a large egg, as much calcium as 8 cups (2 L) of raw broccoli, as much potassium as a medium-size banana, and almost half the vitamin B12 you need in a day. Milk is a source of 15 essential nutrients!
Having tummy troubles?
Don’t self-diagnose – and that includes Googling it. Everyone’s gut health is unique. Consult a health-care professional, such as a registered dietitian with expertise in digestive health, to work out the best gut-health strategy for you.
Susan I Barr, PhD
Professor Emeritus of Nutrition
Food, Nutrition and Health
The University of British Columbia
1. National Institutes of Health. NIH Consensus Development Conference Statement: Lactose Intolerance and Health. NIH Consens State Sci Statements 2010;27(2).