Lactose, Dairy, and Eating Disorder Recovery

The Milky Way: Why We Encourage Inclusion of Dairy in Eating Disorder Recovery

by Shelly Bar, MD, KatieGrubiak, RDN, and Lauren Muhlheim, Psy.D.

Dairy is tasty and good for you. Despite this, there are a lot of folks who are scared of it. You may have eliminated dairy from your diet in pursuit of better health or better digestion. Maybe you believe that the elimination of dairy would help with weight loss. You may have experienced gastrointestinal distress following the consumption of dairy products, concluded that you are lactose-intolerant, and decided you should therefore avoid dairy-rich foods like ice cream and pizza. However, did you know that—especially if you have an eating disorder or disordered eating —this might not be necessary and might actually make things worse?

In this article, we will discuss the many dietary benefits of dairy. We will also explain lactose intolerance and various interventions to address it so that dairy can remain a part of your diet.

Why Dairy is Important

Dairy, in both solid and liquid forms, is an excellent source of macro and micronutrients. Besides providing a balanced synergy of protein, carbohydrates, and—when it has not been removed from the product—fat, dairy provides a significant source of vitamins and minerals, including electrolytes. Milk is a significant source of calcium (300 mg per cup), potassium, magnesium, phosphorus, iodine, zinc, and B vitamins. Vitamin A and D are usually added to milk during processing, making it a good source of these nutrients as well.

Calcium is a crucial mineral for all teens and all people with eating disorders due to the risk of bone loss. Four glasses of milk a day provide approximately 1200 mg of calcium, meeting the daily needs of most teens and adults. Other dairy sources—such as cheese—can have the calcium equivalency of a glass of milk. Therefore, consuming four calcium-rich food or beverage sources daily can prevent the need for calcium supplementation.

The Advantage of Dairy Milks

The U. S. Food and Drug Administration (FDA) requires standardization of products labeled as cow’s milk. This means the macro and micronutrient composition in one cup of milk must remain the same across all manufacturers.  The only variation allowed is the percentage of fat—skim/non-fat, 1%, 2%, or whole—which can in turn alter the amount of fat-soluble Vitamins A and D that are added. Thus, you can be guaranteed to know exactly what specific amount of each nutrient you are getting consistently by drinking a glass of milk.

By contrast, standardization is not required for non-dairy milks, so their nutritional content can vary widely. Each manufacturer can determine the formulation of their beverage and the amount of macro and micro-nutrients it provides. On the whole, they provide fewer nutrients than cow’s milk. Some people might even make non-dairy milks at home. These would almost certainly be deficient in nutrients compared to cow’s milk.

Bioavailability—the body’s ability to utilize a nutrient—is another concern.  Bioavailability depends not only on the specific form a nutrient takes in a food, but on the other nutrients alongside which it is absorbed. In cow’s milk, calcium appears as calcium phosphate, which on its own is 30% bioavailable. Cow’s milk also contains optimal amounts of Vitamin D, phosphorus, magnesium, and zinc, synergistically enhancing this availability. Non-dairy milks may not contain adequate calcium in a form or nutrient combination for the body to easily access it. Some manufacturers are adding these nutrients in an attempt to market the beverage as promoting bone health. If the manufacturers of non-dairy milks are trying to model their products after cow’s milk, one must ask the question: why not drink the real thing?

Other Factors that Make Cow’s Milk Superior to Non-dairy Milks:

• Protein: Nutritional recommendations encourage adequate protein intake. Cow’s milk contains significantly more proten than most non-dairy milks, with the exception of soy milk. Some manufacturers of non-dairy milk are seeking ways to boost their protein content in response to consumer demand.
• Carbohydrates: It is recommended that a majority of one’s total daily calories come from carbohydrates. Cow’s milk has carbohydrates sourced from naturally-occurring lactose. Non-dairy milks have varying amounts and sources of carbohydrates. Since manufacturers often market to “health-conscious” consumers—from our perspective, unnecessarily concerned about sugar—carbohydrate amounts in these products are often much lower. The naturally occurring carbohydrates in cow’s milk, in combination with protein and fat, assist in moderating blood sugar and replacing glycogen stores in muscle. Have you ever heard of refueling after a workout with chocolate cow’s milk? We cannot rely on non-dairy milks to offer the same synergy.
• Fat: Fat is an essential part of one’s daily intake. Whole –or 2%–cow’s milk contains vital fat. This provides an optimal amount of essential fatty acids as well as satiety. The non-dairy milk manufacturers, marketing to the “health-conscious” consumer provide lower-fat products which are less optimal for health and satiety.

Why Are So Many People Scared of Milk?

Diet culture—as well as the clever branding of alternative milk products—appears to have increased fear of dairy products. Many people succumb to the belief that dairy is somehow harmful. They may be afraid of the fat in milk products. It may be that people who are looking for a reason to justify dairy avoidance will pin the blame on lactose intolerance. It has become trendy to seek out non-dairy milk alternatives. This is often veiled under the belief that lactose is bad for health.

In this context, it is important to understand that our human ancestors continued to consume milk and dairy products despite displaying symptoms of lactose intolerance for thousands of years, without any ill effects. 

What is Lactose Intolerance?

Lactose intolerance is an inability to digest lactose, the sugar that occurs naturally in milk. Lactase—spelled with an “a”—is an enzyme produced in the small intestine which is responsible for breaking down lactose. When a person has insufficient lactase in their small intestine, the normal bacteria in our gastrointestinal tract take over and break down the lactose carbohydrate to create energy for themselves. When this happens, we get the production of gas and also increased motility of the gut. This is often what people refer to as symptoms of “toots and shoots.”

All female mammals produce milk to feed their young. The nursing babies digest the milk with the help of lactase. Usually, when the young mammals are weaned, they stop producing lactase, which makes sense practically. Why should our bodies waste energy making an enzyme that is no longer needed?

Humans, however, are unique among mammals in that we continue consuming milk and dairy products into adulthood. Approximately one-third of the population has a genetic mutation that allows us to produce lactase throughout our lives, making it easier to digest milk.

What are the Symptoms of Lactose Intolerance and How Common is It?

The other two-thirds of humans experience some degree of lactose intolerance. It is estimated that 36% of Americans and 68% of the world population have some degree of lactose intolerance. 

The symptoms of lactose intolerance include:

• Diarrhea
• Nausea, and sometimes vomiting
• Stomach cramps
• Stomach pain
• Bloating
• Gas

These symptoms usually occur within 30 minutes to 2 hours of consuming products with lactose. Lactose intolerance often runs in families and is most common in Asian Americans, African Americans, Mexican Americans, and Native Americans.

The other question that often arises is why some dairy foods cause gas and abdominal pain while other dairy foods do not. There is no clear answer to this question. Some people will say that their symptoms will start only after eating a great deal of dairy-based foods—such as pizza followed by ice cream.  Others will feel it immediately after only small amounts of dairy. It is thought that fermented dairy products like yogurt and hard cheeses are easier to digest.

What Are the Health Risks of Being Lactose-Intolerant?

Research shows that people who cannot make lactase do not suffer any significant health consequences. They do not die at a higher rate, do not have weaker bones, and have just as many children as people with the mutation do. In short, the risk is discomfort.

Most people have a partial deficiency rather than a complete deficiency of lactase enzyme, meaning they make some—if not a totally sufficient—amount of lactase. For people with eating disorders, it is important to understand that temporary partial deficiencies can occur when one decreases the amount of dairy they are eating, thus depressing the production of lactase enzyme. When a person is malnourished, it is likely they will produce less lactase. This may occur when someone has been restricting dairy foods, either because they fear that the foods are not “healthy” or because the dairy foods are causing physical distress.

This can in fact become a self-maintaining cycle: where someone has started to restrict dairy, then starts producing less lactase, then experiences distress when eating dairy, concludes they are intolerant and restricts further. At many eating disorder treatment centers, it is often presumed that patients who have been restricting their intake will experience at least temporary partial lactose intolerance and so they are treated with the presumption that they will need additional lactase.

How Do You Manage Lactose Intolerance?

Fortunately, the solution need not be to avoid dairy altogether. The pharmaceutical industry has introduced lactase pills that clients can ingest prior to eating dairy products. The pills work like lactase produced in the body to break down the lactose in milk. Lactase pills help clients with malnutrition from any cause, as the amount of lactase enzyme produced and/or available is insufficient in their gut due to malnourishment even though they are not technically lactose intolerant. This allows them to better digest the dairy products that often add higher fat content to foods. The milk industry has also introduced lactose-free milk with added lactase. This product has nearly the same taste, texture, and nutritional benefits as milk. It does tend to be a little sweeter.

The Importance of Dairy for Eating Disorder Recovery

For a person with an eating disorder, dairy can be a critical food source. Milk has more calories and total macro and micro-nutrients than alternatives and can facilitate the refeeding process for those needing to restore weight. By contrast, milk avoidance undermines recovery by perpetuating fear around commonly-encountered animal-based foods and beverages and creating situations in which one can’t get all of one’s nutritional needs met. Just think about how many situations in which you find yourself in which pizza is the primary nutritive substance. While ethics around consuming dairy are often stated as a reason to avoid it, our highest obligation is to the patient.  In the context of an active eating disorder, it is best to reincorporate all foods and beverages. Later in recovery when rationalization is less of a concern, ethical tradeoffs can be re-evaluated.

If dairy products cause physical distress, we encourage the use of lactose-free milk or lactase pills until dairy is better tolerated. Dairy can also be gradually added back in an exposure-based hierarchical way. This is essential in preventing any fear associated with dairy and allowing the normalization of dairy into everyday diets. Most people can work through “temporary” lactose intolerance in this way.

We do not encourage the elimination of dairy from the diet unless a medical doctor trained in eating disorders has deemed it medically necessary. A medical doctor is also the only one who should recommend the removal of dairy due to a milk protein allergy (specifically whey protein or casein protein). However, this type of allergy is rare, occurring in less than 2% of the population. Children are more susceptible to milk protein allergies, but most outgrow their allergy by 5 years of age.

Why Include Dairy in Eating Disorder Recovery

We know that more varied and higher fat diets lead to more lasting recovery.  It is in the best interest of every person with an eating disorder to include as many dairy foods as possible in their recovery meal plan. If you have eliminated dairy from your diet or are supporting someone who has, we strongly encourage working towards the inclusion of dairy products. We recommend adding dairy back gradually and to use lactase pills to manage any physical symptoms. You may use lactase pills safely long-term.

Dairy-rich foods are a traditional part of many food cultures. We want you to be able to enjoy an ice cream outing with friends, shared late-night pizza ordered in, and social gatherings around a cheese board. Dairy foods are some of the tastiest and most joyful foods. You deserve to able to enjoy them while strengthening your eating disorder recovery.

Source

Evershed, R.P., Davey Smith, G., Roffet-Salque, M. et al. Dairying, diseases and the evolution of lactase persistence in Europe. Nature 608, 336–345 (2022). https://doi.org/10.1038/s41586-022-05010-7