Lactose Intolerance: Health Authorities' Recommendations

This overview of how to manage lactose intolerance focuses on the recommendations of national authorities such as the National Institutes of Health,¹ the American Academy of Pediatrics Committee on Nutrition,² and the National Medical Association.^3,4

Health concerns of restricting the consumption of dairy products

Many individuals who perceive themselves to be lactose intolerant avoid dairy products. However, according to health authorities, it is not necessary for those with lactose intolerance to restrict their intake of dairy products or exclude them from their diets.^1-5

Although restricting lactose intake may improve gastrointestinal symptoms, the long-term effects of a diet low in or free of dairy products are of nutritional concern.^4,6 Restricting dairy intake deprives individuals of readily accessible sources of calcium, vitamin D, and other key nutrients.^1,4

The 2020-2025 Dietary Guidelines for Americans (DGA) recommends 2.5 servings of dairy/day for most children and 3 servings/day for adolescents and adults, acknowledging its nutrient density.⁷ A 2024 study using data from the National Health and Nutrition Examination Surveys (NHANES) 2015-2016, and 2017-2018 revealed that dairy foods are among the largest contributors of nutrients in the US food supply.⁴ Among children and adolescents (2-18 years), the nutrient contributions of dairy foods were approximately:

• 66% of total vitamin D;
• 62% of total calcium;
• 38% of total  vitamin A and B12;
• 36% of total phosphorus.

Among adults (19+ years), dairy foods contributed:

• 50% of total calcium;
• 46% of total vitamin D;
• 27% of total vitamin A;
• 25% of total vitamin B12 and phosphorus.

Evidence indicates that children and adolescents who do not consume the recommended amounts of milk and milk products fail to meet their calcium requirements, which may prevent them from reaching peak bone mass. Insufficient dairy intake may also increase the risk for osteoporosis among older adults and has been linked to a higher risk of fractures.^1,6 Studies have linked the regular intake of dairy products (especially fermented and vitamin D fortified products) to improvements in bone health, body composition, oral health, and potentially mental health among the children and adolescents age groups.⁴

Moreover, studies have revealed the beneficial effects of milk and milk products on different health outcomes, including a reduced risk of hypertension, stroke, cardiovascular disease, colorectal cancer, osteoporosis, obesity, metabolic syndrome,  Alzheimer’s disease, and diabetes.^9,10 In a national multi-ethnic U.S. survey, higher rates of hypertension and diabetes were observed among individuals with self-perceived lactose intolerance.⁸

Management strategies for lactose intolerance

Various management approaches have been shown to effectively alleviate the symptoms of lactose intolerance:

1. Ingesting limited amounts of lactose at a time

It is best to incorporate small amounts of milk or other lactose-containing foods in one's diet and space out intake throughout the day. Most studies show that individuals with lactose intolerance do not experience symptoms after ingesting small amounts of lactose-containing foods. In general, up to 12 grams of lactose (the equivalent of 1 cup of milk) in a single dose can be tolerated without significant symptoms, especially if taken with other foods.^1,4 Most people with lactose intolerance, including children, can tolerate up to 2 cups of milk a day, divided into smaller quantities.^2,5 Regular consumption of lactose-containing foods may promote microbial adaptations in the colon in response to higher lactose levels, thereby reducing symptoms of lactose intolerance. In this way, the undigested lactose that ends up in the colon can act as a selective prebiotic, potentially improving microbiome composition while offering health benefits.⁴

2. Consuming milk and dairy products with other foods

Milk and dairy products are better tolerated if consumed with other foods or incorporated in a dish. The digestion of milk is slowed down when it is taken with a meal, resulting in a slower release of lactose in the small intestine, thereby reducing the lactose load to be digested at any one time.^4-11

Ingestion with other solid foods, particularly those high in soluble fibre, also delays gastric emptying, which provides additional time for intestinal lactase to digest the lactose.^2,5

3. Opting for dairy products such as yogurt, kefir, cheese, and chocolate milk

Yogurt, kefir, and cheese are produced by the fermentation of milk by lactic acid bacteria (in the case of kefir, yeast is used). During this process, a certain quantity of lactose is converted to lactic acid acid while a wide variety of health-promoting bioactive metabolites are produced. Therefore, many fermented dairy products are generally well tolerated, as they not only often contain lower amounts of lactose but also contain beneficial active bacteria cultures which can alter the gut microbiome to better digest lactose.^4,5,12 In particular, long-standing research suggests that yogurt demonstrates the strongest effects on reducing symptoms of lactose intolerance, potentially due to the specific probiotic strains used during production, namely lactic acid bacteria and bifidobacteria.⁴ In addition, the semisolid state of yogurt slows gastric emptying and gastrointestinal transit, providing more time for lactose digestion.^2,3

Some examples of cheeses that contain very little lactose are Mozzarella, Cheddar, Swiss, Brie, and Blue (see table below).^1,3

Chocolate milk also tends to be better tolerated than plain milk, although the reason is unclear.¹¹ 

4. Preferring lactose-free and lactose-reduced milk and dairy products

In its Updated Consensus Statement, the National Medical Association reports that lactose-free dairy products are the most ideal substitute for regular dairy products among individuals with lactose intolerance.³ In addition, palatability is important; evidence indicates that children prefer lactose-free cow’s milk over soy beverages.³

Furthermore, fortified beverages and other calcium-containing foods are not nutritionally equivalent replacements for cow’s milk. Incorporating such foods in one's diet may alter the overall dietary pattern, resulting in suboptimal intake of other key nutrients such as protein, magnesium, potassium, riboflavin and vitamin B₁₂.^3,4 Additionally, it is important to consider that both the quality and quantity of many nutrients, such as calcium and protein, in plant-based may differ from dairy, often negatively. Consequently, dairy and plant-based beverages should not be regarded as nutritionally interchangeable options.⁴

5. Taking lactase enzyme pills

Oral lactase enzyme pills are another option to improve lactose digestion for those with lactose intolerance.^1,3,4 It is recommended that the pills be taken with the first sip or bite of the dairy product.^1,3

Calcium and lactose content in common milk products¹³

Lactose intolerance, whether real or perceived, should not be a barrier to achieving a healthy diet.

Milk and milk products are nutritious foods that provide several essential nutrients such as calcium, vitamin D, magnesium, potassium, and protein, and are associated with several health benefits including bone health and a reduced risk of hypertension, type 2 diabetes, and colorectal cancer.

Among individuals with diagnosed lactose intolerance, various approaches can be employed to maintain milk and milk products as part of a healthy diet.