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Cow’s Milk Casomorphin, Crib Death, and Autism

Evolution devised an ingenious way to bond infant to mother: proteins in milk that break down into peptides that have opiate-like drug effects. But what if a breastfeeding mother is herself effectively suckling by still drinking milk into adulthood? Evolution never counted on that, which may explain a recent case report entitled “Cow’s Milk-Induced Infant Apnea With Increased Serum Content Of Bovine Beta Casomorphin 5” published in the Journal of Pediatric Gastroenterology and Nutrition.

Casomorphin is one of the opioid compounds formed in our stomachs when we drink milk. Infant apnea refers to when a baby stops breathing. The researchers “report a case of a breast-fed infant with recurrent apnea episodes, which have always been preceded by his mother’s consumption of fresh cow’s milk.” Lab tests revealed a high level of casomorphin in the child’s blood, leading researchers to speculate that it was the “opioid activity that may have a depressive effect on the respiratory center in the central nervous system and induce a phenomenon called milk apnea.”

“The aim of the present report,” the paper concludes, “is to draw researchers’ attention to the possibility of occurrence of a systemic reaction with an apnea seizure on the infant’s exposure to the proteins in cow’s milk. We are convinced that such a clinical situation occurs rarely; however, it is accompanied by a real threat to the infant’s life that can be avoided when applying a simple and not costly dietetic intervention…[a dairy-free diet]”. You can see more about the report in my 3-min. video Cow’s Milk-Induced Infant Apnea.

The reason this is so concerning is that as many as 1 in 10 infants with recurrent apneic episodes cannot be saved and die of SIDS, sudden infant death syndrome (also known as crib death). SIDS is the leading cause of death for healthy infants after one month of age. One in every two thousand American babies dies this way. Every day six babies stop crying and twelve parents start.

The suggestion that the opiate-like effects of a protein in cow’s milk could cause an infant to stop breathing was so provocative that researchers have started testing other high-risk kids. In my 2-min. video, Cow’s Milk Casomorphin and Crib Death, I detail a study in which the blood levels of the morphine-like peptides from cow milk averaged three times higher in infants with acute life-threatening episodes than those in healthy infants. It turns out there is an enzyme that gets rid of casomorphins, but the activity of that enzyme in the affected group was only half that of the healthy kids. Thus, some babies may just not be able to clear it out of their systems fast enough and are placed at risk for SIDS. The researchers conclude: “Penetration of beta-casomorphins into the infant’s immature central nervous system may inhibit the respiratory center in the brainstem leading to abnormal ventilatory responses, hypercapnia [too much carbon dioxide], hypoxia [not enough oxygen], apnea, and death.”

The opiate-like casomorphins liberated from the cow’s milk protein, casein, are also accused of participating in the cause of other conditions including type I diabetes, postpartum psychosis, circulatory disorders, food allergies, and autism–the subject of my 2-min. video Cow’s Milk Casomorphin and Autism.

Breast is always best, but the breast milk of women eating plant-based diets may be better still since they not only reduce or eliminate exposure to bovine casomorphins, but also contain lower levels of industrial pollutants like dioxins. See, for example, my 4-min. video Flame Retardant Chemical Contamination. For other effects animal products may have on healthy development see Dairy & Sexual Precocity and Protein and Puberty. No wonder Dr. Spock—the most esteemed pediatrician of all time—ended up recommending children be raised without exposure to meat and dairy.

-Michael Greger, M.D.


Michael Greger M.D., FACLM

Michael Greger, M.D. FACLM, is a physician, New York Times bestselling author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial.

21 responses to “Cow’s Milk Casomorphin, Crib Death, and Autism

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  1. I didn’t think I could be surprised by anything related to the effects of consuming animal foods, but this made me tear up. SIDS? How tragic. I’m almost speechless. 

    1. I don’t know what to do!!!
      I never give my 1yr old cow’s milk but cheese and sometimes yoghurt.
      I would like to avoid milk products totally but I need help how to provide my LO a balanced, healthy diet with enough calcium, phosphorus and riboflavin.
      Without alternatives I m too scared to abandon dairy products .

      1. Hi Sindy M Nagy,
        Please note Academy of nutrition and dietetics indicates that, since breast milk is such a rich source of nutrients, vegan mothers may want to breast-feed for more than one year. After 12 months, vegan infants may be weaned with full-fat soy milk that is fortified with calcium and vitamins B12 and D. If a vegan or vegetarian baby is weaned from breast milk before 12 months, they should receive iron-fortified infant formula until they are 1 year old. Milk alternatives, such as soy, rice, almond, hemp, etc., are not recommended during the first year of life because they do not have the right amounts of nutrients.

        Nutrients Needing Special Attention

        When feeding vegetarian or vegan children, pay close attention to the following nutrients:

        Vitamin B12: Vegetarians can obtain B12 from milk products and eggs and fortified foods such as soy beverages, cereals and meat substitutes. Vegans, both breast-feeding moms and children, need a good source of B12 and may require a supplement in addition to fortified sources of this vitamin.
        Vitamin D: The American Academy of Pediatrics recommends all breast-fed infants receive 400 IU per day of supplemental vitamin D starting shortly after birth. This should continue until your child consumes the same amount of vitamin D from fortified milk: at least one quart per day of whole cow’s milk or full-fat soy milk. However, these milks should not be introduced before 12 months of age.
        Calcium: Breast- and formula-fed babies, as well as toddlers who consume milk and dairy foods, usually get plenty of additional calcium from foods including yogurt and cheese. For vegan toddlers, calcium-fortified foods and beverages or supplements may be necessary. See a registered dietitian nutritionist for advice.
        Iron: The iron content of breast milk is low, even if moms are eating well. Full-term infants are born with enough iron for 4 to 6 months. After this age, breastfed infants need an outside source, so ask your pediatrician about supplemental iron until solid foods are introduced. Other sources of iron include iron-fortified cereals and formulas, as well as mashed tofu and well-cooked pureed beans.
        Protein: Babies need plenty of protein for rapid growth during the first year. Both breast milk and infant formula supply protein. When solid foods are introduced, plant-based sources of protein include well-cooked pureed beans and mashed tofu. After 12 months of age, fortified full-fat soy milk is another option. Lacto-ovo toddlers can get protein from yogurt, cottage cheese and eggs.
        Dietary Fiber: Lots of fiber can fill up toddlers quickly. Provide frequent meals and snacks. Use some refined grains, such as fortified cereals, breads and pasta, or peel the skin on fruits and serve cooked instead of raw vegetables more often.
        To help vegetarian children meet their energy and nutrient needs and to learn more about foods that may pose a choking hazard, consult a registered dietitian nutritionist.

  2. If people want to read more about this topic, I would strongly recommend the book Devil in the Milk by Keith Woodford. It covers a wide range of research and health problems associated with the bovine beta casomorphin and is written with meticulous scientific standards. The book is quite a rivetting read because it is all about the politics of the dairy industry and what they have done to try to cover this issue up. Woodford is a New Zealand Professor of Agribusiness, so he has great credibility to write this. The book is not however anti dairy milk consumption per se, it is anti the particular type of milk (A1) that is the standard cows milk available and which produces these problems because of the casomorphin component. There is another genetic strain of cows that produce a different type of milk (A2: available on a very small scale in New Zealand where I live), that has a different molecular structure so it does not produce the same problems. But most people can’t get A2 milk, so if you are looking for further reasons to give up cows milk, this book will provide it.

  3. Such information is very vital for new parents to know!!
    This should be printed out in guides and given to parents. It could prevent so
    many deaths and so many tears.

  4. How about milk and Type 1 diabetes?

    I quoted entire article because you have to sign up (free) to access the site and some may not want to. Thought this pretty interesting as it could explain the seeming link between early dairy consumption and T1 diabetes; perhaps the intestinal inflammation from the milk could be what allows the virus access to the blood stream and from there the pancreas. 

    Diabetes linked to flu

    16:08 02 November 2012 by Debora MacKenzie
    For similar stories, visit the Epidemics and Pandemics Topic Guide
    The flu virus has another trick up its sleeve – it may trigger diabetes. The good news is that this discovery may give us a way to prevent some forms of the disease.

    In diabetes, cells do not take up sugar from the blood. This can happen because cells have lost sensitivity to the hormone insulin, leading to what is called type 2 diabetes. Linked to diet and lifestyle, this form of the disease is rapidly becoming more common worldwide. Another cause of diabetes happens when the immune system destroys the pancreatic cells that produce insulin. People inherit a genetic predisposition for this condition, called type 1 diabetes, but an environmental trigger is also needed for it to appear.

    Since the 1970s, researchers have suspected that viruses may provide this trigger, as type 1 diabetes often sets in suddenly after an infection. Enteroviruses and rotaviruses were both implicated; something about these infections confuses the immune system enough to make it attack the pancreas. But the picture remained unclear.

    Then Ilaria Capua, of the World Organisation for Animal Health reference lab for bird flu in Legnaro, Italy, and her team decided to infect turkeys with flu. They did this because they knew birds with flu often have an inflamed pancreas, even when they have strains of the virus that do not normally spread outside the lungs. The team found that many of the turkeys developed severe pancreatic damage and diabetes.

    Next, the researchers infected human pancreatic tissue with two common flu viruses. Both “grew really well” in the tissue, including in insulin-producing cells, says Capua.

    Inflammatory response

    Crucially, the presence of flu in the pancreatic cells triggered production of a set of inflammatory chemicals that have been shown to be central to the autoimmune reactions that lead to type 1 diabetes. One theory is that immune cells present bits of the infected tissue to destructive T-cells, to teach them to recognise the virus. But in the process the T-cells also learn to recognise the cells that make insulin, and to destroy them.

    Can flu reach the pancreas? In humans, the virus is normally restricted to the lungs and gut, but can sometimes get into the blood. The virus might also travel up the duct that links the small intestine to the pancreas, Capua suspects. “Either way, when it gets to the pancreas it finds a good place to replicate.”

    Capua is now testing the effects of flu on mouse models of type 1 diabetes. She is also looking for signs of recent flu infection in people with newly diagnosed diabetes. She suspects the H1N1 swine flu virus that caused the pandemic of 2009, and is still circulating, could be a particularly good trigger. Doctors in Japan and Italy have reported many newly diagnosed cases of type 1 diabetes in people who had recently had flu, and an upsurge in type 1 diabetes after the 2009 pandemic.

    Real impact

    “The great thing is that even if flu only causes a few per cent of type 1 diabetes cases, we can vaccinate and prevent flu in people who are genetically predisposed, and that can have a real impact,” says Capua. There are 65,000 new cases of type 1 diabetes worldwide annually, and that figure is growing by 3 to 5 per cent each year.

    The link between diabetes and flu adds to growing evidence that many diseases considered non-infectious are actually caused by infection – and can therefore spread.

    There is also new evidence that flu can cause heart attacks. Previously, this was suspected, because of the surge in heart attacks that regularly follows the annual flu season. But researchers at the University of Toronto, Canada, have now demonstrated the effect in individual patients. They reported this week that vaccinating adults for flu, whether they already have cardiac problems or not, makes them half as likely to have a heart attack or stroke in the following year (Canadian Journal of Cardiology,

    Journal reference: Journal of Virology,

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  6. Thanks Dr. Greger for this important info. But “evolution devised”? Only intelligence can create information. Only intelligence can devise. :-)

    1. So Wedi, don’t you think that “evolution” is intelligence (or maybe more appropriately “Intelligence”) in motion/action?

      1. Unless I miss your point, or you just want to play with word definitions, my answer is No. “Evolution” normally implies the involvement of no intelligence in any meaningful sense. Motion is irrelevant. Yet evolution requires increase in, that is, creation of, information. And there is no scientific basis to suppose that can happen without some intelligent being thinking it up and making it happen. Therefore in the paradigm of our current scientific understanding of how the universe works, naturalistic evolution is impossible. Thus I believe it was God who devised the “ingenious way to bond infant to mother.” If you are suggesting that God used evolutionary processes to create, well, that’s another discussion.

        1. You are playing with words if you think “intelligent design” as somehow separate from the process itself is somehow par of our current scientific paradigm. It in no way requires a somehow mystically separate from the act intelligence to make the act itself intelligent. The entire Universe is of a piece and that is inherently intelligent, creative; no need for outside agency. We are it and it is us.

          1. Cool. If you want to ascribe intelligence to a mystical personless concept of “Universe,” that’s fine with me. But if the 2nd law is true, “Universe” couldn’t have always existed. And so I wonder how it created itself. I believe a theistic view squares with the facts best, as I understand them.

            1. I agree in a sense. Universe is the Theos; Universe is the divine person, not a separate old dude w/ a long white beard somehow outside of creation. And Universe likely not created but always has been; creative process unfolding eternally forever and ever, ahmen. Ahwomen.

  7. Good article, very intereststing, very one sided thou – would like to read an article on the million reasons why you SHOULD have dairy products in your diet!

    1. I think Dr. Greger would reply that whatever nutritional benefits you can get from dairy are available in plant foods, without the dangers, which are proven by multiplied scientific studies. The reasons why you SHOULD consume dairy products include the good taste, and perhaps a desire to support those in the industry. The important thing is to learn about the pros and cons, weigh the known dangers and benefits, and then make an informed choice which is right for you.

    2. eka: There are a million articles about aliens at “Area 51”, but that doesn’t sway me into believing that they are or were there. :-)

      An article is only one sided if there are really two sides to report. I would encourage you to do a lot more research on dairy if you are still eating it. Good luck.

  8. There is simply not enough evidence to say for sure what is going on here. It is interesting and I hope the people researching it can get grant money, but if you look at the literature it’s not possible to say that we actually know eating wheat or milk has an opioid like effect. Only the studies that support his point are mentioned here but there are plenty that cast doubt on these hypotheses that weren’t mentioned (selection bias perhaps). For example one study showed that injected casomorphins had no effect likely because they could not cross the blood brain barrier (it has only been speculated that they can cross it). This is just a correlation at this point meaning it could be caused by other factors related to this casomorphin degrading enzyme or lower levels of this enzyme could be co-occuring with something else which is causing adverse effects. This is one of the reasons the scientific community thinks all of the stuff related to autism and vaccines and etc. is fake, because people are presenting the information in an inaccurate and alarmist manner. This causes a reactionary response from experts and they immediately discount the information because it was introduced in such a biased way. It’s also offensive when people who have some other profession try to act as though their ideas, or the ideas from some blog or youtube video, are just as valid as an actual experts who spent half their life studying it so they could help heal people. They don’t know everything, but they know mountains more than the average person. A small amount of knowledge is a dangerous thing, because you’re not aware of the knowledge you’re still missing. If you believe something just because you read it or watched it without actually understanding how the science works or the other relevant research in the field, don’t pretend your opinion has any clout. If the public health community keep these things in mind when trying to learn and communicate, the science will proceed much faster and with less opposition. Because of the bad press and armchair science associated with some of these issues its damn near impossible to get funding to study them.

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