Home > Blog > Adrenal Health > Casein in Milk Friend or Foe? Should You Drink Milk? Learn More

Casein in Milk Friend or Foe? Should You Drink Milk? Learn More

casein in milk causing symptoms of lactose intoleranceThe number of people considered lactose intolerant is increasing on a daily basis. But this ‘lactose intolerance’ might, in fact, be due to something totally unrelated. Many of these people might, in fact, not necessarily be intolerant to lactose at all, but rather unable to properly digest the casein in milk. More specifically, they may be unable to digest a certain type of casein in milk found in American cattle.

Research indicates that up to one in every four Americans, considered lactose intolerant, are actually unable to tolerate A1, a type of casein, found in the majority of American milk-producing cows.

What is Casein?

Milk contains many nutrients, proteins, and carbohydrates. Of the protein content in milk, 80% of it is casein. Another example is whey protein. You do, however, get many different variations of casein, the most predominant two being A1 and A2. These two casein variations differ by a single amino acid. This small difference causes a difference in the milk’s action on your intestinal tract. The different amino acids present in A1 casein and A2 casein are histidine and proline respectively.

Those countries where A1 casein in milk is prevalent, more people have trouble with their gastrointestinal health. This is opposed to those countries where the A2 casein in milk is prevalent. America, for example, mostly relies on the high volume milk producing Holstein breed which mostly carries the A1 casein protein, while breeds such as the Jersey, Guernsey, and the majority of Asian and African cow breeds have the A2 protein in their milk. Although research is not yet conclusive, the A1 casein in milk has been linked to a wide range of health conditions, including heart disease, autism, and diabetes.

The Difference Between A1 and A2 Beta Casein in Milk

All cows, at one time, were A2 beta-casein cows. Then, a few thousand years ago, due to a mutation, A1 beta-casein cows came into being. Now there are cows that produce A1 milk only, A2 milk only, or a mixture of both A1 and A2 milk. The A1 beta-casein in milk, once ingested, releases beta-casomorphin 7 (BCM7).

BCM7 is a naturally occurring opioid with a structure that is very similar to morphine. Tests conducted on individuals with autism and schizophrenia have found that their blood samples have higher amounts of BCM7 than other people. Research on the gut has also shown a correlation between BCM7 and autism. Seemingly, BCM7, in gut cells, causes a chain reaction resulting in a shortage of antioxidants in your neural cells, most noticeably, glutathione. Furthermore, research conducted, specifically on mice, found that when fed a diet, rich in A1 beta-casein, the mice underwent an overproduction of enzymes and immune system regulators. A number of studies have shown links to heart disease and autoimmune issues such as asthma and eczema.

casein in milk you drinkThere is also growing support that A1 beta-casein in milk is a contributing factor towards gut inflammation; thus leaky gut syndrome. Seemingly, the BCM7 opioid moves through the damaged gut lining and enters the body, causing problems. This is because the histidine amino acid is not, biochemically, able to hold onto the BCM7 opioid. Your body’s immune response tries to fight the BCM7, resulting in inflammation and its accompanying symptoms, i.e. redness, swelling, pain, etc. and autoimmune issues. Lastly, studies would suggest that A1 casein in milk changes your hormone function and has a negative effect on your nervous system.

A2 beta-casein, on the other hand, is claimed to show none of the characteristics or negative health connotations of A1 beta casein. This implies that it does not promote the buildup of fats in injured blood vessels, does not break down into the BCM7 opioid to the same degree as the A1 casein, is easily digested and causes no inflammation to your digestive tract, and is not a contributing factor to the development of any kinds of autoimmune diseases. Studies, in fact, show that the majority of people who ingest milk containing A2 casein show none of the symptoms associated with an intolerance to A1 casein in milk.

Common symptoms shown by those with intolerance to A1 casein in milk include:

  • Gastrointestinal issues such as constipation, diarrhea, bloating, stomach aches
  • Brain fog
  • Fatigue
  • Weight gain
  • Acne
  • Asthma
  • Eczema
  • Allergies
  • Aching joints, arthritis

The Role of Inflammation and Hormonal Dysfunction on Your Health

Your body can be likened to a sophisticated piece of machinery. Each part contributes to the perfect function of the whole. When one part, however, becomes infected or broken down, it affects the functionality of the whole machine – in this case, your body. Of course, when one part of a machine becomes over-worked, it starts failing eventually, causing a cascading effect which implies other parts of the machine are no longer able to work at their optimal level. Your body functions in much the same manner.

When under stress, your body goes into protective mode, immediately producing more and more cortisol in order to combat the problem. This is typically your body’s first line of defense, as the cortisol hormone is your fight or flight hormone. It, thus, helps you to cope with stressful events.

The stress talked about here can come from anything. Emotional, financial, physical, etc. As such, it can even come from drinking A1 Casein milk.

Hormonal imbalance

The constant production of cortisol is not always a good thing. When your body produces cortisol, other functions are either paired down or completely stopped. They are not considered necessary to sustain life. The problem arises when the threat persists. Your adrenal glands, as part of the hypothalamic-pituitary-adrenal (HPA) axis, keeps on producing cortisol, often at elevated levels. When this occurs, a hormonal imbalance often results due to other necessary hormones not being produced as they should. As the situation progresses and the stress continues, your adrenal glands can no longer produce the needed cortisol, as they tire and the cortisol precursor hormones are depleted. Adrenal fatigue syndrome is often the result.

casein in milk and sugar balance

Sugar imbalance

While this is happening, your blood sugar levels are affected. The elevated cortisol production inhibits your insulin production in the pancreas because it needs the glucose in your blood for energy.

Immune system is suppressed

Cortisol serves to reduce inflammation. However, a prolonged period of cortisol production resulting in a constant suppression of inflammation, ultimately, suppressing your immune system. This can occur when you drink milk on a daily basis and are constantly exposing your body to inflammatory compounds. A weakened immune system is not able to combat inflammation and leads to many health problems, such as an increased susceptibility to colds and flu, a higher risk of getting cancer, food allergies, autoimmune issues, and gastrointestinal problems.

Gastrointestinal problems

Because cortisol production activates your sympathetic nervous system, your parasympathetic nervous system is suppressed. This is because these two nervous systems are not able to operate at the same time. Your parasympathetic nervous system is important for the digestion and absorption of nutrients. During periods of high cortisol production, the digestion and absorption of nutrients becomes compromised, causing many gastrointestinal problems, including irritable bowel syndrome (leaky gut).

The A1 Casein in Milk Connection to Adrenal Fatigue

While the A1 beta-casein in milk may not cause adrenal fatigue, evidence suggests that it is a contributing factor. This is due to the amino acid BCM7 which is an opioid. Opioids, it would appear, have an inhibiting effect on your body’s cortisol production in the adrenal gland. This results in what is known as secondary adrenal insufficiency. As mentioned, low cortisol production results in a weakened immune system and a decrease in your body’s ability to fight inflammation. At the same time, Casein can inflame your body, putting stress on your adrenals to produce more cortisol. This can be a vicious cycle if continued on a daily basis.

Casein and Milk Allergies or Sensitivity

A milk intolerance is vastly different from a milk allergy. A milk allergy implies you are allergic to the specific proteins found in milk, while an intolerance is usually ascribed to the lactose (sugar) in milk or the milk proteins. Intolerance is not an allergic condition but rather refers to the body’s digestive system not being able to digest these substances in milk properly.

Symptoms of lactose intolerance include diarrhea, bloating, and discomfort in the abdominal area. The symptoms of milk protein intolerance usually take a few days to manifest and include irritable bowel, constipation, bloating, headaches or migraines, sinusitis, mood fluctuations, general fatigue, eczema, and skin rashes.

A definite milk allergy is only picked up by means of allergy tests.

People who have a milk allergy should preferably stay away from both A1 or A2 beta-casein milk and milk products.

The Availability of A2 Casein Milk

There is no way, as yet, to remove the A1 casein compound in cow’s milk. Fortunately, there are certain ranchers that breed only A2 homozygous herds. These herds are, unfortunately, not yet fed on a 100% organic diet. In other words, they are not solely fed on grass. This is largely due to the presence of snow during the winter months and ranchers having to feed their herds stored foodstuffs.

casein in milk, organic optionsIf you are in the fortunate position of being able to source outlets for this milk, do know that it is slightly more expensive than the more freely available A1 produced milk. If you want to cut out A1 milk, and A2 milk is not available, a safe option is a plant-based milk. These include soy milk, almond milk, rice milk, and oat milk.

A2 protein powder milk is not, as yet, available in the U.S.A. It is, however, available in Australia and certain Asian countries such as China – in both a whole cream and nonfat variety.

Milk Is, Generally Speaking, Good for You

There is no denying that milk, indeed, is good for you, although, as an adult, you do not really need milk as a food source. There are so many better options to get the nutrients you need. Babies are totally dependent on it for sustenance during the first few months of their lives, although in this instance it would be mothers’ milk or baby formula which is specially formulated and prepared. After weaning off mother’s milk, there are not many good reasons to continue consuming cow’s milk.

Milk is a source of:

  • Calcium: necessary for the maintenance and development of bones and teeth. It also plays a role in your blood clotting ability and thus the healing of wounds and maintaining blood pressure.
  • Choline: plays a role in muscle development, the transmission of nerve impulses, learning, and memory.
  • Vitamin D: needed for calcium absorption and proper immune function.
  • Potassium: reduces your risk of stroke, high blood pressure, and heart disease. Additionally, it preserves bone density, reduces the development of kidney stones, and guards against the loss of muscle mass.
  • Magnesium: much needed to support the adrenal glands during the early stages of adrenal fatigue. Too much magnesium may not be tolerated in advanced stages, of adrenal fatigue.
  • Vitamin B6 and vitamin B12: play a role in cellular metabolism. Additionally, vitamin B6 is a necessary component for the creation of many hormone types. Vitamin B12 maintains red blood cells, helps with cellular repair, and is needed for energy production.

Reverse Inflammation with Glutathione

Glutathione is a powerful antioxidant made by our bodies. Its role is to fight off inflammation, protect cells from oxidative damage, and aid in liver function. Chronic stress, however, causes your glutathione reserves to become depleted, resulting in a number of related symptoms. These include chemical sensitivities, leaky gut, inflammatory disorders, and autoimmune diseases, to name but a few.

In order to improve your body’s ability to create the necessary levels of glutathione, in addition to supplementation, you need to remove the stressors that cause the depletion. These include metabolic imbalances (e.g. a hormonal imbalance or immune system), food intolerances, too much sugar in the diet, processed foods, smoking, and even alcohol consumption, among others.

There are two ways in which to supplement with glutathione: orally, and intravenously. There are, however, certain precautions to keep in mind with glutathione supplementation.

glutathione and casein in milkPrecautions when taking glutathione supplements

  • Oral glutathione may not be safe during pregnancy or for younger children.
  • It may not be safe to use by those with low blood pressure.
  • Oral supplementation with glutathione, especially in large doses, may be harmful to those suffering from asthma.
  • Oral intake of glutathione, as well as topical applications, may inhibit melanin synthesis.
  • May result in neurological side effects in those who suffer from headaches and neurological disorders.
  • Flooding your bloodstream with glutathione for a long period may reduce inter-cellular production.


There is no doubt that A2 beta-casein milk is much healthier for you than A1 beta-casein. Many people who believe they are lactose intolerant are actually sensitive to the A1-beta casein found in much of the milk purchased in stores today. If in doubt, however, remember that adults and older children do not really need milk in their diet. Although milk has many health benefits, these same benefits are to be had by following a healthy diet.

© Copyright 2017 Michael Lam, M.D. All Rights Reserved.
Ready to Start Your
Adrenal Fatigue Recovery Journey?
Dr. Lam Coaching is rated 4.7 / 5 average from 70+ reviews on Google