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by Robert Keith Wallace, PhD, and Samantha Wallace

Welcome to the Dairy Wars. If we Google the words “dairy” and “inflammation” contradictory research papers and blogs appear. Some are adamant that dairy causes inflammation. Others completely dismiss the idea as unscientific and cite recent review articles, which actually say that dairy is largely neutral and even anti-inflammatory (1-15).

Let’s take a step back to get the big picture: There are two main types of substances in dairy products that might cause inflammation. The first is the milk sugar or lactose; the second includes the proteins, casein and whey.

Dairy Sugar

Lactose is composed of two simpler sugars, glucose and galactose. As infants, most of us can produce an enzyme called lactase, which breaks the lactose into glucose and galactose. These two sugars are absorbed in the cells of our small intestine without difficulty and help provide energy for our growing bodies. In time, and depending on our genetic make up, the situation may change.

From 65% to 75% of the world population loses the ability to digest lactose in early childhood and develops the now well known condition, lactose intolerance. This condition occurs when we do not produce the enzyme lactase. As a result, lactose is not broken down and absorbed by the small intestine, but instead, goes to the large intestine and is fermented, causing symptoms such as abdominal pain, bloating, diarrhea, gas, and nausea—similar to the symptoms seen in Irritable bowel Syndrome (IBS) and Inflammatory Bowel Disease (IBD). What all of these symptoms have in common is a disturbed microbiome and an aggravated gut lining. And it is widely accepted that a disruption in the gut tends to cause a type of low-grade inflammation.

How common is lactose intolerance? Only 5% to 10% of Americans, whose origins are from Northern Europe, have this condition. Other ethnic populations in the US have a much higher percentage. Asian Americans, for example, are 90% lactose intolerant, while Mexican Americans are 50% lactose intolerant. And approximately 75 % of African Americans, Native Americans, and Jewish Americans are lactose intolerant (3).

Some genetically lactose intolerant groups, however, manage to consume large quantities of milk, largely without symptoms. Experts suggest that one explanation for this is that these people regularly eat some type of natural probiotic, like yogurt, which alters the microbiome so that the lactose is digested without the usual symptoms of lactose intolerance.

The genetic trait of lactose intolerance manifests at different ages and in different degrees. For some, it comes between the ages of one and three, while for others it occurs later in life. We might be able to enjoy milk in the morning with our coffee or cereal, but if we have an ice cream later in the afternoon, we suddenly become gassy and bloated. Each of us is a mixture of genes that can be turned on and off at different times in response to specific environmental stimuli, including age and diet.

There are ways to cope with lactose intolerance. We can switch to lactose-free milk, or plant-based milks such as soy milk, rice milk, almond milk, and coconut milk. Most of the lactose is removed in the making of butter, and even more in clarified butter or ghee. The process of making yogurt produces an enzyme that removes most of the lactose, although the amount removed can vary depending on the type. Lactose can be removed in the fermentation process of cheese making, especially in a hard, aged cheese. Dairy products are often present in other types of food, so if you have this condition, you probably know that you must check the ingredients of almost everything you eat.

Dairy Proteins

The second element in dairy products, which might cause inflammation, is protein. And the most obvious type of inflammation caused by proteins is a milk allergy. A milk allergy is a serious inflammatory reaction and symptoms include an itchy rash, throat or tongue swelling, shortness of breath, vomiting, lightheadedness, and low blood pressure. Milk allergies are present in 1% to 3% of the world population, being highest in infants and lowest in adults (8). It is important to be properly tested and diagnosed. Six major allergenic proteins have been identified in cow’s milk as the cause of a milk allergy. Four of these are from casein proteins, and two from whey proteins.

The amount of casein protein varies in different types of milk. In cow’s milk, casein makes up to 80% of the protein. In human milk, it makes up only 40% of the protein. Casein is also found in cheese, and is used as a food additive. There are two distinct types of casein—A1 and A2 beta-casein. The difference between these two proteins is one amino acid in each. In A1 casein there is an amino acid called histidine, and in A2 casein there is an amino acid called proline in that same position.

Scientists believe that this difference was caused by a genetic mutation in cows, which occurred when cattle were taken north into Europe some 5,000 to 10,000 years ago. Modern day cows in Europe (excluding France), the United States, Australia, and New Zealand produce a mixture of A1 and A2 beta-casein, while there are cows in Asia and Africa that produce only the A2 beta-casein. Breeds such as Guernsey, Jersey, Asian herds, human milk, and others (sheep, goat, etc.), produce mostly A2 beta-casein, while Holstein, Friesian, Ayrshire, and British Shorthorn breeds produce equal amounts of A1 and A2 casein (9).

This genetic difference in the breeds affects the way casein is broken apart by the digestive enzymes in our gut. In the digestion of A1 casein, an opioid peptide is produced, called beta-casomorphin-7 (BCM-7). It is still unclear how much of this peptide is absorbed into our blood and what effects it has, but a number of papers suggest that it is harmful to our health (10,16).

The difference between A1 and A2 milk was brought to public attention when a company in New Zealand, The a2 Milk Company Limited (previously A2 Corporation), made claims that A1 milk was responsible for a number of diseases. They have since been forced to withdraw these claims, and in 2009, the European Food Safety Authority (EFSA) reviewed the scientific literature and found no relationship between chronic diseases and A1 milk (11).

And this particular Dairy War is not yet over. Recent studies in China found that there are a number of benefits of A2 milk, compared to A1 milk, in terms of digestive discomfort and elimination. It should be noted the researchers involved in these studies were supported in various ways by the a2 Milk Company (12-16).

Another type of protein found in milk is from whey, which has become a popular protein supplement for athletes. Again, the potential benefits of whey are not without controversy and a wide variety of studies differ in outcome.

Finally, there is the issue of the hormones, antibiotics, and other contaminants that are given to cows, as well as the regularity that each of these get into our dairy products. Although strict government regulations are in place, the problem continues.

The Dairy Wars are full of conflicting information. Dairy products can cause inflammation, especially in the case of milk allergies. They can also cause many digestive problems in large numbers of people who are lactose intolerant. But dairy products have been an integral part of many of the great traditions of health, including Ayurveda, Apk. The answer to this seeming paradox may have to do specific recommendations. For example, Ayurveda says that milk should always be boiled with the addition of digestive spices like ginger. It also says that the milk should be taken warm and not cold. Ayurveda considers milk more beneficial for one type and not another, depending on seasonal factors and the health condition of the individual.

Each of us is different and we may have periods in our lives during which we are more or less sensitive to dairy and other foods. Tests and experts can help evaluate our tolerance to dairy products, but the simplest procedure is for us to eliminate dairy for several weeks, then reintroduce it into our diet and carefully monitor its effects.

Learning which foods are right for us is part of our personal path of self-discovery.


  1. The Danger of Dairy:
  2. Bordoni, A et al., Dairy products and inflammation: A review of the clinical evidence, Critical Reviews in Food Science and Nutrition, 2017; 57:12, 2497-2525
  3. Lactose Intolerance:
  4. Lordan, R et al., Dairy Fats and Cardiovascular Disease: Do We Really Need to be Concerned? Foods 2018, 7(3), 29
  5. Drouin-Chartier, J-P et al., Comprehensive Review of the Impact of Dairy Foods and Dairy Fat on Cardiometabolic Risk. Advances in Nutrition. 2016;7(6):1041-1051
  6. Lordan, R and Zabetakis, I, Invited review: The anti-inflammatory properties of dairy lipids. J Dairy Sci. 2017; 100(6):4197-4212
  7. Telle-Hansen, VH et al., Does dietary fat affect inflammatory markers in overweight and obese individuals?—a review of randomized controlled trials from 2010 to 2016. Genes & Nutrition. 2017;12:26
  8. Bahna SL, Cow’s milk allergy versus cow milk intolerance. Ann Allergy Asthma Immunol. 2002; 89:6(1): 56–60
  9. Casein:
  10. Kost, NV et al., Beta-casomorphins-7 in infants on different type of feeding and different levels of psychomotor development. Peptides. 2009 Oct; 30(10):1854-60
  11. Truswell, AS, The A2 milk case: a critical review, European Journal of Clinical Nutrition, 2005; 59 (5): 623–631European Food Safety Authority, Review of the potential health impact of β-casomorphins and related peptides. EFSA Journal. 2009; 7 (2): 231r
  12. Pal, S et al., Milk Intolerance, Beta-Casein and Lactose. Nutrients. 2015; 7(9): 7285-7297
  13. Jianqin, S et al., Effects of milk containing only A2 beta casein versus milk containing both A1 and A2 beta casein proteins on gastrointestinal physiology, symptoms of discomfort, and cognitive behavior of people with self-reported intolerance to traditional cows’ milk. Nutr J. 2016; 15:35
  14. Jianqin, S et al., Erratum to: ‘Effects of milk containing only A2 beta casein versus milk containing both A1 and A2 beta casein proteins on gastrointestinal physiology, symptoms of discomfort, and cognitive behavior of people with self-reported intolerance to traditional cows’ milk’. Nutr J. 2016; 15:45
  15. He, M et al., Effects of cow’s milk beta-casein variants on symptoms of milk intolerance in Chinese adults: a multicentre, randomised controlled study. Nutr J. 2017; 16:72
  16. Brooke-Taylor, S et al., Systematic Review of the Gastrointestinal Effects of A1 Compared with A2 β-Casein, Advances in Nutrition, 2017; 8: 5, (1) 739–748

ROBERT KEITH WALLACE is a pioneering researcher on the physiology of consciousness. His work has inspired hundreds of studies on the benefits of meditation and other mind-body techniques, and his findings have been published in Science, American Journal of Physiology, and Scientific American. After receiving his BS in physics and his PhD in physiology from UCLA, he conducted postgraduate research at Harvard University.

Dr. Wallace serves as Professor and Chairman of the Department of Physiology and Health, Director of Research, and Trustee of Maharishi University of Management (MUM) in Fairfield, Iowa. He helped create the first fully accredited Masters of Science degree in Maharishi AyurVeda and Integrative Medicine in the US.

Dr. Wallace is the author of several books, including Gut Crisis: How Diet, Probiotics, and Friendly Bacteria Help You Lose Weight and Heal Your Body and Mind with his wife Samantha Wallace.

SAMANTHA JONES WALLACE is a former model, featured in Vogue, Cosmopolitan, and Look Magazine. A lifelong practitioner of Transcendental Meditation, she has a deep understanding of Ayurveda and its relationship to health and wellbeing.

The coauthor of Quantum Golf, Samantha is an editor of Dharma Parenting, and coauthor of Gut Crisis. She is finishing a book called Real Deep True Beauty, which emphasizes Essential Oil Skincare, and Ayurveda.