To date, there are few food groups that are as controversial as dairy. Although years of research have suggested consuming dairy is associated with reduced risk of chronic disease and improving overall health, more recent studies have begun to question the necessary role of milk and other dairy products in a healthy diet.

Despite the decades-long success of “Got Milk?” — one of the most iconic ad campaigns of all time — there seems to be growing skepticism among the general public and even some medical professionals about the health consequences of dairy, especially for those living with a dairy intolerance or allergies.

So is dairy bad for you? How do we know if we should swap milk and other forms of dairy for non-dairy alternatives such as almond milk? In this article we’ll review federal nutrition guidelines, opinions from leading medical organizations, and research on the pros and cons of keeping dairy in your diet.  

What Constitutes “Dairy”?

A simple definition for dairy is any food or drink that is made from the milk products of mammals. Many dairy products come from cows, but the food group also includes foods from goats, sheep, and buffalo.

When we think of dairy, many of us conjure up a glass of milk or a slice of cheese, but dairy comprises more than just those 2 foods. The following items are all considered to be part of the dairy group:

• yogurt
• kefir
• ghee
• butter
• cream
• whey products
• lactose-free milk

(Source)

Can Dairy Be Plant-Based?

The U.S. Department of Agriculture (USDA) currently classifies fortified soy milk and yogurt as dairy in their Dietary Guidelines for Americans (DGA) but this inclusion is far from universal. The USDA doesn’t consider plant-based alternatives made from almond, rice, coconut, oat, and hemp to be part of the dairy group because their nutrition content isn’t similar to dairy milk or fortified soy milk. (Source, Source)

Current U.S. Dairy Guidelines

Every 5 years the USDA and the U.S. Department of Health and Human Services (HHS) publish the DGA, the nation's go-to resource for nutrition recommendations and dietary advice. The goal is to educate Americans on the importance of fueling their bodies with nutrient-dense foods and beverages, including dairy. (Source)

The 2020–2025 DGA recommends adults consume 3 servings of dairy products per day and that children consume 2 to 2.5 servings per day. Examples of a single dairy serving include 1.5 ounces of hard cheese or 8 ounces of dairy milk, soy milk, or yogurt.

For those who are lactose intolerant, the guidelines suggest low-lactose and lactose-free dairy products. The DGA also includes alternatives that are fortified with calcium, vitamin A, and vitamin D — such as soy beverages and soy yogurt — in the dairy group for people who simply prefer to avoid dairy.

Let’s Ask the Professionals: Is Dairy Bad for You?

The decision to continue recommending dairy doesn’t come without debate from the medical community.

Some Experts Are Skeptical

Leading up to the publication of the 2020 DGA, Harvard University professors Walter Willett and David Ludwig published a review claiming that “the role of dairy in human nutrition and disease prevention warrants careful assessment.” (Source)

Willett and Ludwig explained that while cow’s milk does offer a valuable combination of macronutrients and micronutrients, those nutrients are also found in other food sources. In their opinion, the optimal intake of milk depends on a person’s overall diet quality, and in some cases too much dairy may actually cause harm.

In August 2020, the Physicians Committee for Responsible Medicine submitted a letter to the USDA and HHS asking them to reconsider the recommendation for 3 daily servings of dairy products. Signed by nearly 500 health care professionals, the letter states that the guideline “preserves antiquated, racially biased dairy-promoting guidelines, despite clear contributions to health problems that take a disproportionate toll in Black Americans and other demographic groups.” (Source)

Canada Offers a Model

As an alternative, the Committee suggested mirroring Canada’s guidelines, which recently stated that dairy isn’t necessary for a balanced diet. In an official recommendation, our neighbors to the north demoted dairy from being its own food group to being an optional protein source. (Source)

Another team of researchers released a similar review on dairy’s place in the federal guidance. Led by Elizabeth Jacobs of the University of Arizona, the team also suggested following Canada’s approach and grouping dairy with protein in order to account for underserved populations with a growing proportion of individuals who cannot digest lactose. (Source)

Is Dairy Actually Important?

Now, before you pour your cow’s milk down the sink, let’s review the research. Below we break down some of the leading reasons to consider keeping — or removing — dairy from your diet.

Dairy Supports Healthy Bones

Although some studies suggest the link between dairy and strong bones is tenuous at best, others conclude that dairy is beneficial for bone health and preventing conditions such as osteoporosis. Dairy products are rich in calcium as well as magnesium, vitamin D, and protein — all nutrients that support healthy bones. Dairy has been shown to improve bone density and decrease the risk of hip fractures. (Source)

If you do opt to drop dairy products, it’s important to find other sources of calcium such as leafy green vegetables, sardines, fortified soy products, and calcium supplements. This is especially important for those living with an autoimmune disease, because calcium plays an important role in keeping the immune system healthy. (Source, Source)

Dairy May Reduce Risk of Obesity

Some research suggests milk and other dairy products may be linked to a lower risk of childhood obesity, possibly due to dairy's supply of protein and amino acids. That same analysis suggests dairy products may help improve body composition and contribute to weight loss among adults. (Source)

Another meta-analysis of randomized controlled trials that studied the effects of dairy on body weight and composition in 18- to 50-year-olds also pointed to a weight loss effect. Evidence found that consuming 2 or more daily servings of dairy as part of a low-calorie diet led to greater body weight and fat mass loss compared to following a low-dairy diet. (Source)

Dairy’s Role in Cancer Risk Is Uncertain

Recent research shows milk and other dairy products may be associated with a greater risk of breast cancer, ovarian cancer, and prostate cancer. However, other studies were unable to confirm a link between consuming dairy and developing breast or ovarian cancer. (Source, Source, Source, Source)

Importantly, data also suggest that some cancers and their treatments may increase the risk of developing an autoimmune condition, and certain autoimmune diseases increase a person’s risk of getting cancer. If this is relevant to you (approximately 50 million Americans are living with autoimmune condition diagnosis, so you wouldn’t be alone), you may want to consider consulting a professional to discuss your dairy intake, among other nutritional and lifestyle changes to support your symptom healing. (Source, Source)

Dairy’s Role in Heart Disease Is Also Uncertain

USDA dietary guidelines recommend choosing low-fat dairy products to limit saturated fat intake. Whole milk and dairy products are high in saturated fatty acids, which are linked to increased risk of cardiovascular issues such as cardiovascular disease, coronary heart disease, and stroke.

Results from three prospective cohort studies support opting for low-fat milk, finding that low-fat milk was associated with less cardiovascular disease and lower mortality than whole milk. The study also found that while 2 servings of dairy per day might not be beneficial for cardiovascular disease, it may be the least harmful — with greater consumption associated with increased cardiovascular disease and mortality. (Source)

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Dairy May Cause Allergy or Intolerance

Dairy contains proteins and sugars that are difficult for some people to digest. Casein and whey are proteins that can cause an immune reaction, while lactose is a sugar that is linked to enzyme deficiency and digestive issues. For those with a dairy allergy, even trace proteins in something like ghee can cause health problems.

One of the leading reasons people choose to avoid dairy products is lactose intolerance, or the inability to digest lactose. Up to 50 million American adults are lactose intolerant, with the highest prevalence among Asian Americans, African Americans, American Indians, and Hispanics or Latinos. (Source)

For people who are lactose intolerant, eating foods with dairy can cause gas, diarrhea, and bloating. Lactose intolerance can be inherited or it can develop due to certain health conditions such as Crohn’s disease or celiac disease. Some people can go years consuming dairy before their intolerance becomes noticeable. (Source)

Dairy should also be avoided by those who are following an autoimmune protocol (AIP) diet to help with gut issues or an autoimmune condition. One of the reasons, as taught by WellTheory’s Certified Nutritionists and Registered Dietitians, is that cow’s milk proteins are known to be gluten cross-reactors. This means if you are sensitive to gluten, the dairy proteins may stimulate your immune system as if you were eating gluten. (Source)

The Form of Dairy Matters

According to the USDA, America’s dairy habits are changing. While overall dairy consumption has remained the same over the last 40 years, people are now eating more yogurt and cheese and drinking a lot less dairy milk. In fact, milk consumption has dropped by about 40% during the past 4 decades, from 0.9 cup-equivalents per person in 1979 to 0.5 cup-equivalents per person in 2019. (Source)

Cultured Dairy May Be More Digestible

The form of dairy consumed is particularly important if you are reintroducing dairy products as part of the AIP diet. In this case, it’s best to choose the products that are least likely to cause a reaction. Nutritionists recommend cultured dairy — such as yogurt, sour cream, and kefir — because the fermentation process converts lactose, a sugar, to lactic acid, leaving these products lower in both sugar and lactose. When it comes to cheese, it's best to choose aged, hard options like cheddar, swiss, and parmesan as they also tend to be low in lactose. (Source)

Full-Fat vs. Low-Fat Dairy

While some high-fat foods, such as olive oil, nuts, and avocados, offer your body essential nutrients, the same logic doesn’t apply to whole milk and full-fat cheese. Organizations such as the American Heart Association and the National Heart, Lung, and Blood Institute suggest choosing fat-free or low-fat dairy products in order to take advantage of the calcium without the saturated fat. (Source, Source)

That said, some research shows the full-fat variety does offer some benefits. And as discussed, full-fat dairy may offer more nutrients and fat-soluble vitamins, without certain proteins and sugar, which makes it more tolerable for those with an autoimmune disease.

Organic vs. Conventional Dairy

Organic food is growing more popular across the country, and organic dairy products are the second-largest organic food group behind organic produce.

Organic milk and conventional milk provide similar nutritional value, but some research suggests that organic milk has higher levels of healthy fatty acids such as omega-3 and polyunsaturated fats. Organic milk may also contain more of another type of fat called conjugated linoleic acid, which is associated with reducing the risk of cancer, obesity, osteoporosis, and heart disease. (Source)

The Bottom Line on Whether Dairy Is Bad for You

Is dairy bad for you? If you’re still struggling with that question, know that the answer is largely personal. Research on the health benefits of dairy consumption is inconclusive, but most professionals agree that up to 3 servings per day is fine for most people, unless you have a dairy intolerance or allergy or are following a plant-based or paleo diet.

If you’re still debating the role of dairy in your diet, don't hesitate to consult a health care provider to review your health history and nutrition goals. At WellTheory, you can work with a Certified Nutritionist and Registered Dietitian to combine dietary and lifestyle changes to help you feel your best. Learn how you can get personalized support from our WellTheory care team.

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