Does Dairy Cause Inflammation? What the Research Says

This article contains additional reporting by Jennifer Chesak.

Does dairy cause inflammation? The short answer is maybe. Perhaps you're on the fence about whether you should skip dairy foods in your diet. The decision may come down to how dairy affects inflammatory markers in your body.

Historically, dairy was thought to cause inflammation. But newer research suggests it doesn't increase biomarkers of chronic inflammation in healthy people.

However, dairy may still not be suitable for some, based on underlying conditions, intolerances, or sensitivities.

Is dairy good for you?

You probably grew up hearing that milk is good for your bones and yogurt is good for your gut.

Indeed, milk contains calcium and vitamin D, which are good for your bones. Yogurt contains probiotics, which are good for your gut. These lines of thinking have likely led dairy to become a staple in many diets.

In developed countries, milk and dairy products make up about 14 percent of overall caloric intake.

Despite the mass production and consumption of dairy, however, allergies and sensitivities to milk are common. In these, and other instances, dairy can be an inflammatory food.

Are you lactose intolerant?

Those with lactose intolerance are unable to digest dairy well because they do not produce adequate amounts of the enzyme lactase, which is required to break down lactose, a sugar found in dairy.

About 65 to 70 percent of the population is lactose intolerant. However, the prevalence varies significantly among different ethnic groups and regions.

• About 20 to 25 percent of white adults are believed to be lactase deficient.
• About 75 to 90 percent of African Americans, Native Americans, and Asian Americans are estimated to have lactose intolerance.

Symptoms of lactose intolerance generally occur within 30 minutes to two hours after ingestion.

However, not all individuals with lactase deficiency experience symptoms of lactose intolerance. Symptomatic individuals represent only about 50 percent of lactase deficiency cases.

Some people with lactose intolerance do not experience symptoms with fermented dairy, like yogurt, or high-fat dairy products, like butter.

If you have small intestinal bacterial overgrowth (SIBO) or irritable bowel syndrome (IBS), you might also negatively react to dairy.

Lactose intolerance symptoms

• abdominal pain
• bloating
• flatulence
• nausea
• diarrhea

Do you have a dairy allergy or sensitivity?

If you produce the lactase enzyme but still react poorly to dairy, you likely have a milk protein allergy, In this case, you experience an allergic response to one or both of the proteins found in dairy—casein and whey.

Dairy protein allergies are most commonly seen in children but can also affect adults.

Symptoms of dairy protein allergy

• swelling of the mouth, lips, or throat
• skin reactions, such as hives or rashes
• increased nasal congestion and mucus production

People can also experience dairy allergy symptoms in the GI tract, such as loose stools, diarrhea, vomiting, and abdominal cramping.

Additionally, if you have increased intestinal permeability, or “leaky gut," your immune system may respond to allergenic components in milk and dairy products.

Dairy sensitivity and celiac disease

Celiac disease and dairy sensitivity share connections. Lactose intolerance is often a symptom of celiac disease, with about quarter of celiac patients experiencing it. This is typically due to secondary lactose intolerance, caused by damage to the small intestine villi.

For many celiac patients, dairy sensitivity is temporary. As the small intestine heals on a gluten-free diet, lactose tolerance often improves.

Does dairy cause inflammation?

If you have a dairy allergy, lactose intolerance, IBS, SIBO, gluten intolerance or intestinal permeability, dairy may promote an inflammatory response when consumed.

Additionally, researchers have found links between milk consumption and the occurrence of acne and eczema.

For Parsley Health members with any of these conditions, we usually recommend following a dairy-free diet. However, research does not support the notion that dairy is inflammatory for people who do not have any of these conditions.

A 2019 review, published in Advances in Nutrition, found that dairy had no pro-inflammatory effects on healthy people or people who have diabetes or metabolic syndrome.

Most recently, a 2020 review reported that eating dairy could even reduce biomarkers of inflammation in some cases where subjects did not have inflammatory disorders or other conditions.

Likewise, a 2017 review that evaluated 52 clinical studies concluded that dairy generally has some anti-inflammatory effects, except in people with known allergies or intolerances.

Additional research has found that total dairy intake could be associated with lower risk of cardiovascular disease and stroke—which have been linked to chronic inflammation.

What are the symptoms of inflammation from dairy?

If you notice bloating, changes in bowel movements, or any other type of digestive upset after eating dairy, these symptoms could signal that dairy causes inflammation for you.

Dairy inflammation symptoms may include changes in your skin: You might notice an uptick in acne, eczema, or psoriasis after dairy intake. If you’re super sensitive to dairy, it may even cause fatigue or brain fog.

An elimination trial is the best way to test whether dairy is inflammatory for you. An elimination trial involves 30 days of completely eliminating dairy from your diet. Then, your provider can work with you to slowly reintroduce dairy to see if you experience a reaction.

Not all dairy is created equal

If you tolerate dairy well and like it, it can be part of a healthy diet. Choose high quality, full-fat, organic, pasture-raised dairy that’s preferably from grass-fed cows, goats, or sheep.

Contrary to previous understanding, full-fat dairy may be more beneficial than low-fat varieties. This is likely because of the higher sugar content in low-fat dairy products.

The dairy source is also a major factor to consider. Conventional dairy products are made from milk that contains hormones, chemicals, and antibiotics—all of which may have negative consequences to your health.

Therefore, opting for organic and pasture-raised varieties from grass-fed cows is your best bet.

Dairy products from goat and sheep may be better tolerated because they contain lower levels of milk proteins since they come from smaller animals.

Milk from goats and sheep also contain the more easily digestible A2 beta-casein, which is a big part of the reason they’re less likely to cause GI symptoms and inflammatory responses when consumed.

For an added bonus, goat and sheep are also less likely to be factory farmed. Therefore, their milk may have fewer additives resulting from their feed.

Some studies suggest that A1 milk consumption may be linked to:

• inflammation
• digestive discomfort
• possible increased risk of heart disease and diabetes

However this research is largely inconclusive. A2 milk is often marketed as a healthier alternative to regular milk. But more research is needed to understand the differences between A1 and A2.

Takeaway

Knowing whether you have a dairy intolerance or sensitivity can help you decide if dairy is right for your diet.

Experimenting with a 30-day dairy-free diet, followed by a formal reintroduction trial, can help you assess any potential negative reactions to dairy.

You can get tested for dairy intolerances, like we do here at Parsley Health, and work with your doctor and other providers to develop the best nutrition plan for your unique needs.