The Adverse Effects of Milk
by Loren Cordain & Pedro Bastos
Came across this yesterday in my files. It’s good stuff and I’m choosing to post it. Apparently, a journalist had written to Loren Cordain for the truth on milk and the following is the response.
Inquiring about the adverse effects of milk consumption, which prompted the following responses from Dr. Cordain and Pedro Bastos.
Hello Dr. Cordain,
- I am working on an article about the negative impact of dairy products on some people. Basically, can you explain why milk is problematic? My understanding is that, similar to gluten, milk is potentially inflammatory, which is why it’s such a common allergen. Can you expand on this?
- If someone is drinking milk now, and not feeling any negative effects, does that mean he doesn’t have an issue with milk?
- What sort of changes have you observed in people who’ve given up dairy?
- Also, are all dairy products problematic, or is milk a particularly bad one?
- What do you recommend in place of milk to fill that nutritional gap?
Thanks so much for your help.
I really am not a world expert when it comes to health problems associated with milk, but I will copy Pedro Bastos, a colleague who is, and who has written a few pieces on this that may help to answer your questions:
Milk has numerous properties that may adversely affect health.
• Paradoxically, milk has a low glycemic response, but has an insulin response similar to eating a chocolate chip cookie or candy. In a recent study of young boys, they became insulin resistance after 7 days on a high milk diet compared to 7 days of a high meat diet.
• In humans, milk drinking elevates a hormone called IGF-1 which increases growth in children, resulting in an increased adult stature, but it also increases the risk for breast, colon and most particularly prostate cancer. How milk drinking increases IGF-1 is not completely known, but two mechanisms have been proposed: 1) bovine milk contains IGF-1 which crosses the human gut barrier, and 2) IGF-1 concentrations in human blood vary with insulin — because milk increases the insulin response so dramatically, then this response in turn may increase IGF-1.
• In numerous epidemiological studies, milk drinking has been associated with an increased risk for numerous autoimmune diseases including multiple sclerosis, rheumatoid arthritis and type 1 diabetes. Young children are particularly at risk for type 1 diabetes if bovine milk exposure occurs before the age of 1 year. In animal models of multiple sclerosis, a particular protein found in milk (butyrophilin) when injected into rats causes the animal equivalent of MS.
• In a series of epidemiological studies from the Harvard School of Public Health, milk drinking has shown to dramatically increase the risk for acne. Once again the mechanism has not been completely worked out but may once again involve milks highly insulinotropic effect and/or various hormones found in milk that bypass the gut barrier and enter circulation.
• In many epidemiological studies, milk drinking increases the risk for atherosclerosis and fatal myocardial infarctions independent of its saturated fat content. Again the mechanisms are unclear, but it likely involves chronic low level inflammation, or perhaps endocrine substances found in bovine milk that adversely interact with mechanisms known to underlie cardiovascular disease.
• Milk contains a hormone called betacellulin which binds a human gut receptor called the epidermal growth factor receptor (EGF-R). In many human cancers, there is massive over expression of this receptor which may be linked to chronic consumption of betacellulin in bovine milk.
• There are many more health problems associated with milk drinking, but these are the ones that come immediately to mind. I’m sure Pedro can add many more.
Are all dairy products problematic, or is milk a particularly bad one?
I believe that all dairy products are problematic. Cheeses do not cause the high insulin response as does milk, yogurt and other fermented dairy products, but is one of the most acidic of all foods. Paradoxically, despite its high calcium content, its net acidic load promotes calcium loss from the bones. Betacellulin is also found in cheese, but many of the other hormones found in milk do not survive the cheese making process.
If someone is drinking milk now, and not feeling any negative effects, does that mean he doesn’t have an issue with milk?
We cannot feel whether or not we are insulin resistant or if bovine hormones are entering our bloodstream, or if our arteries are becoming clogged with the atherosclerotic process, but we can notice improvements in acne and symptoms of allergy (wheezing, sneezing, rashes etc.), or autoimmune disease.
What sort of changes have you observed in people who’ve given up dairy?
I am not a clinician, and generally the anecdotal responses I am privy to involve people not just giving up dairy only, but rather adopting a Paleo diet in which all dairy is eliminated, along with all grains, processed foods, salt, legumes and potatoes. If you go to my website and look at the success stories section, you can read about these people.
What do you recommend in place of milk to fill that nutritional gap?
I don’t view it as a nutritional gap, but rather a liability which causes our health to suffer in the long run. We have run nutritional comparisons of the following food groups (meats, seafood’s, fresh fruits, fresh vegetables, whole grains, nuts & seeds, milk) and published our results in the highest impact nutritional journal in the world, the American Journal of Clinical Nutrition. We found that for these 7 food groups, milk ranked third from last for the 14 most commonly lacking nutrients in the US diet. Hence, the commonly held notion that milk is a highly nutritious food is simply untrue.
Except for calcium, milk is a lightweight for many of the vitamins and minerals needed for optimal human health. Healthy bones result from positive calcium balance. Calcium balance is like a bank account and results from how much calcium we put into our bodies minus how much we lose. The Dairy Council focuses their ads upon the input side of the calcium equation — more, more, more. However, the calcium that we ultimately lose in our urine is just as important. If we lose more calcium in our urine than we take in, we will never be in calcium balance, no matter how much milk we drink.
The most important factor determining urinary calcium loss is acid base balance. A net acid yielding diet promotes calcium loss in the urine, whereas a net base yielding diet prevents urinary calcium loss. Foods which are base yielding are fruits and vegetables. Studies have shown that by consuming about 25-30 % of our daily energy as fruits and veggies, we can maintain calcium balance at low calcium intakes without milk consumption. Humans have existed on this planet for 2.5 million years, and only in the past 10,000 have we ever consumed milk or dairy products. Like all other mammals on the planet, we did quite well without milk (once we were weaned) for the rest of our adult lives. Have you ever thought about how an elephant can grow such large, health and strong bones without drinking the milk of another species?
I hope this helps.
Loren Cordain, Ph.D., Professor
There is a large body of evidence that up until 9,000 years ago in the Middle East1 and 7,000 years ago in Northern Europe2, no human being on the planet consumed non human milk or dairy products. So on an evolutionary time scale, non-human milk is a relatively newcomer into human diet. By using the evolutionary template, and knowing that that milk is species specific, we would expect this new habit to have unintended consequences, which go way beyond lactose intolerance (which is actually very common), since only a minor percentage of the world’s population continues to produce lactase into adulthood3.
Indeed there are several lines of evidence raising concerns with milk and dairy intake, such as:
1) Milk and fermented milk (yoghurt, for instance), despite having a low glycemic index and load, elicit a very high insulin response and this has been shown repeatedly in intervention studies 4-9.
As you may be aware, constantly increasing insulinemia may downregulate the insulin receptor, and hence lead to insulin resistance10-12, which in turn is the primary metabolic defect underlying The Metabolic Syndrome13, and may be a driving force in obesity14, 15. It should also be mentioned that a chronic state of Hyperinsulinemia may set a hormonal cascade that ultimately results in cancer, acne and juvenile myopia, among other diseases13.
Indeed, a high bovine milk diet has been shown to cause insulin resistance in boys9. Moreover, dairy intake is strongly associated with a higher incidence of Acne16-18 and moderately associated with Prostate Cancer19-23.
2) Cow’s milk appears to be involved in certain autoimmune diseases (AD):
• Various epidemiological studies have associated it with Type 1 Diabetes24-31, especially when the initial exposure begins in the first months of life.
• Epidemiological studies have repeatedly shown a strong correlation between Multiple Sclerosis and cow’s milk consumption32-36.
• There is molecular mimicry between Bovine Serum Albumin and Human Collagen Type 1, which has implications for Rheumatoid Arthritis37. Indeed, case studies have shown that elimination of milk and dairy products from the diets of patients with RA improved symptoms, and the disease was markedly exacerbated on re-challenge37.
• Bovine milk is also implicated (or appears to have adverse effects) in other auto-immune diseases, such as Crohn’s disease38, Sjögren’s syndrome39, IgA nephropathy40-42, Behçet’s disease43, and even Celiac disease40.
3) Hormones in Milk:
In addition to proteins, fats, lactose, vitamins and minerals, milk contains various growth-stimulating steroid and peptide hormone and also catalysts, transporters and stabilizers that ensure their maximum bioactivity45.
Here’s a short list of some hormones present in cow’s milk that could be problematic for humans:
Cow’s Milk, as well as human milk (and presumably milk from all mammals) contains insulin46-49, and we know that bovine insulin – BI (which differs from human insulin by three amino acids50) survives pasteurization, because immunity to this hormone is common in children who consume cow’s milk or who have been exposed to infant formulas containing cow’s milk51-54. This not only confirms that BI is present in commercial pasteurized milk, but also in infant formulas and perhaps other dairy products (although direct evidence is lacking). Moreover, these studies provide evidence that BI survives the human digestive processes and crosses the gut barrier intact, although this could be related to the fact that infants have higher intestinal permeability than older children and adults50. Nevertheless, various factors may cause the so called “leaky gut” in virtually everyone, so we shouldn’t dismiss bovine insulin altogether.
Cow’s milk contains active IGF-155, but this has been largely dismissed as relevant, since pasteurization (time and temperature are crucial factors) and fermentation appears to reduce its content56, 57. Yet cow’s milk consumption, compared to various foods, is associated with a higher plasma IGF-1 concentrations in humans (both children58-61 and adults62-66), which could be due to calcium in milk (which has been shown to increase IGF-1 in boys and girls67), the effect of milk upon insulinemia (the high elevation of plasma insulin caused by milk drinking 4-9 could lead to a higher plasma IGF-113) or indeed residual IGF-1 in casein68 (the major protein in milk).
Betacellulin (BTC) belongs to the Epidermal Growth Factor family of hormones69, and is found not only in cow’s milk70 and whey70, but also in cheese70. Therefore, it survives pasteurization and processing. Although no direct evidence yet exists, bovine milk does contain peptidase inhibitors which prevent human gut enzymes from degrading EGF5 (and most likely BTC), and a low pH such as that found in the gut, it does not impair or prevent BTC from binding its receptor71. Finally, there is a luminally expressed EGF receptor in the gut, through which BTC may enter circulation69.
The major sources of animal-derived estrogens in the human diet are believed to be milk and dairy products, which presumably account for 70–80% of the total estrogens consumed72, 73. Furthermore, it has been pointed out that most milk for human consumption is obtained from cows in the latter half of pregnancy when estrogen metabolites levels are greatly elevated72-74. Confirming this, US researchers have measured estrogen metabolites in various milks and shown that buttermilk contains the highest total amount of estrogen metabolites, followed by skim milk, 2% milk and whole milk72. Therefore, estrogen metabolites appear to survive pasteurization, and estrone sulphate, which comprises 45% of the conjugated estrogens in Premarin and Prempro (the most frequently prescribed hormone replacement therapy for menopausal women73) has high oral bioactivity73, and is the most prevalent form of estrogen in cow’s milk72, 73.
There are also other steroid hormones in commercial pasteurized cow’s milk, such as progesterone, 5α-androstanedione and 5α-pregnanedione, which are dihydrotestosterone (DHT) precursors75.
As expected from the evidence presented, dairy intake is strongly associated with a higher incidence of acne16-18, moderately associated with prostate cancer19-23, and mildly associated with ovarian cancer76, 77.
Dairy consumption was also associated with an increased incidence of testicular78, 79, kidney80, and head and neck cancer81, but very few studies have been conducted to draw more significant conclusions.
Although epidemiological evidence can’t show a clear cause and effect, and clearly much more studies need to be conducted, the current evidence strongly suggests that cow’s milk may be implicated in a variety of autoimmune diseases, certain cancers, as well as acne.
4) Milk has a very high calcium/magnesium ratio and may contribute to some micronutrient imbalances.(#1 see note)
5) There is evidence of higher fracture incidence rates in countries with higher milk and calcium intake82, some long term prospective studies have failed to show a benefit from drinking milk or taking calcium supplements83-85, and a recent meta-analysis, which analyzed seven prospective cohort studies (170,991 women), five prospective cohort studies (68,606 men), five clinical trials, (5,666 women, and 1,074 men), and four clinical trials with separate results for hip fracture (6,504 subjects), concluded that calcium intake doesn’t decrease the risk for fractures86. Calcium intake is only part of the story; we need to consider GI absorption and renal excretion. In these regards, vegetables from the brassica family have a clear advantage over milk87.
I know this may sound overly alarming, and possibly exaggerated, but given what I know about milk, I have a hard time recommending it – even though it has some positive effects, such as being a cheap source of high quality protein and various micronutrients.
For those who are fortunate and have access to good (real) food, supplements such as Vitamin D, (which by the way, may be needed in much higher doses than the ones provided by three or four servings of dairy a day), and adopt a diet that has a low glycemic load, is moderate in fructose, is net base yielding and provides sufficient protein, soluble fiber, essential fatty acids, especially EPA, DHA, GLA and AA (with a w6/w3 ratio < 4/1) and all the micronutrients, I believe milk is not necessary.
I hope this helps.
Pedro Carrera Bastos
Nutrition Researcher, Lisbon, Portugal
(My Comment: With especial regard to #4 above “Milk”, and it’s high calcium-magnesium ratio. Readers know that I have been pounding the books concerning cardiac-pulmonary causative factors and with this in mind am still deeply immersed in Dr Mildred Seelig’s “The Magnesium Factor.” Tho now deceased, she remains the imminent authority and her book is definitive.
Those of us with these problems soon learn that there is no help for this condition until the magnesium factor has become harmonized and balanced. This is easier said than done Her book explains the various kinds of magnesium and discusses the bio-availability of the different formulae, i.e., a 500 mg capsule may have only 35, 80 or at most 125 essential magnesium available for the body’s absorption. So it is easy to see how hard it is to acquire enough of this into our system.Healthy, normal consumption would be about 700 to 1,000 mg daily. Almost no one is getting this amount. Critical cardio patients need 1200 and up to double that amount – but under a doctor’s care.
At a time 7 or 8 years ago I was taking so much magnesium at doctors orders (for my heart condition and the severe arrhythmia which was beating up my heart, I was literally housebound because I couldn’t stray too far from the toilet. I was trying to take 1200 mg daily and it still wasn’t enough. I obviously was so out of balance and no one knew how to solve this. But then doctors were primarily trying to correct the condition with pharmaceuticals and weren’t really into herbal solutions. If it hadn’t been for this one sainted man on the west coast who consented to help me long distance, I probably wouldn’t be here now. Still, my dilemma wasn’t solved which is why I’m still at it.
Dr Seelig’s book speaks of some who can’t be helped with oral magnesium alone if they are too far out of balance as they can’t absorb what they are given. One can need different procedures – even injections, but mostly difficult cases require a physician trained in natural methods if true correction is to be forthcoming. I am my mother’s daughter, have a bit of her iron will and fortitude, I guess, cause I sure haven’t had the resolve I needed. But I’m workin on it.
The book says to back off when diarrhea arises. Perhaps the doctors didn’t really understand my predicament or believe me. After five years of severe diarrhea, I discovered Transdermal Magnesium and bought that book explaining it all. Helped enormously. I put it on my belly 2 – 3 times a day and rubbed it in. In time, I came out of the diarrhea phase, but the docs said I needed more. So I take pills and also rub it on. Now, I’ve ordered something called Nature’s Calm, a liquid (well – a powder which you mix in water) which the book says is effective and fast acting. This obviously is a good thing if one is having a scary pounding session.. . can take a spoonful
CALCIUM – MAGNESIUM RATIO (thank God I’ve had the good sense NOT to take calcium supplements of any kind)
Both elements have an important role in our health; they are like two sides of a physiological coin. Calcium exists outside the cell and it’s job is to stimulate or excite the nerves. Magnesium exists almost entirely inside the cells and it’s influence is to calm down. Calcium, together with potassium are involved with muscle contraction and clots the blood. While magnesium is needed to relax the muscle and keeps the blood flowing and helps to prevent congealing.
Calcium is found mainly in bones and gives hardness, while magnesium is mainly in soft structure and the bone matrix , the soft structure within the bone (marrow) which is mainly protein and magnesium. The normal concentration of the Magnesium ion inside the cell is 10,000 to 1 with that of intracellular calcium ions – – under healthy conditions.
If however, magnesium becomes depleted or insufficient, the calcium ions float into the cell which is where they do not belong and all hell can break loose.. This puts the cells into hyperactive state. For a cardio patient, this is not a good thing. Okay, I’m going to cool it now – not going to keep on about the book. Just know that it is a great read and if one has Syndrome X, diabetes, or heart disease and so on – – this is so relevant. Course, I’m kinda a bibliophile, don’t worry, it’s not catching – you either have it or you don’t. Was hoping to show how relevant this article truly is. What a great service someone like Loren Cordain has given to the world. He remains the top of the heap for me.
If only we could all just get back to basics with our eating routines – go simple and easy, uncomplicated – – get away from anything prepared and comes in a can or box, maybe grow something (like sprouts), and quit for good, grains and dairy and learn something about low glycemic foods, we could look in the mirror and smile knowing that we are doing our best, because we love ourselves and we deserve it. . .because we know – You Are What You Eat. Jan)