Dairy foods, including cow’s milk, make up a substantial part of the typical western diet. Many contemporary humans consume milk for breakfast every morning, as well as regularly eat other dairy products such as yogurt and cheese. This is particularly true in the U.S. and in Northern European countries such as Finland and Sweden.
It’s not surprising that dairy consumption is so widespread in those parts of the world, seeing as most people who live there are able to consume lactose-containing foods without experiencing acute gastrointestinal distress and hold the belief that it’s healthy to consume milk and other dairy foods. This widely held belief has gradually been incorporated into the public’s mind over generations, helped by the dairy industry and public health authorities who both highlight the fact that dairy foods such as milk and yogurt are rich in calcium, protein, and vitamins.
What’s often forgotten is that dairy products are a very recent addition to the human diet. Throughout more than 99.6% of the evolutionary history of our genus, Homo, no humans on this planet regularly consumed the milk of another animal. Moreover, milk is a very special type of food, in the sense that its purpose is to induce mammalian, postnatal growth, development, and immune maturation. In other words, from a Darwinian point of view, it seems highly plausible that cow’s milk (or milk from another animal for that matter), as well as other dairy foods, don’t agree with the human biology.
Does milk really do the body good?
Let’s listen to the “milk-expert”, who is the single best expert on epigenetic effects of milk consumption: Dr. Melnik. This guy is very high on the list of people on this planet who know the most about milk as it relates to human health and nutrition. In other words, when he speaks, you’d be wise to listen to the interview below.
1. In your scientific papers, you present evidence indicating that milk consumption is a risk factor for a variety of western illnesses. What types of diseases are particularly relevant in this respect?
Diseases promoted by milk consumption are acne, obesity, type 2 diabetes, prostate cancer, and Parkinson´s disease.
2. A lot of people grow up learning that cow’s milk is packed with high-quality protein, calcium, and vitamins and is an essential part of a healthy diet. Part of the reason for this is undoubtedly that the dairy industry has managed to imprint these ideas into the public’s mind via clever marketing campaigns. The fact that mammalian milk is a very powerful, complex substance that was designed, via natural selection, to promote the growth and development of suckling infants is given much less attention. What don’t people know about milk? How does the consumption of milk derived from another animal (e.g., a cow) affect the human body? What makes milk different from other foods that are a part of the human diet? I’m particularly interested in hearing about how milk consumption affects mTORC1 signaling and growth, which has been the focus of much of your research.
I came to the conclusion that milk is not a simple food but a most sophisticated endocrine signaling system of mammals to promote postnatal growth, let´s compare it to a specialized form of postnatal doping. I realized that milk provides two key signals fulfilling its task: essential branched-chain amino acids (BCAAs=milk´s hardware) and milk´s gene regulatory software (milk-derived miroRNAs transported in nanovesicles called exosomes).
These two pathways enhance the activity of the kinase mTORC1. Over-activation of mTORC1 drives all diseases of civilization such as obesity, type 2 diabetes, cancer, and neurodegenerative diseases.
3. Dairy foods such as cow’s milk contain many different substances that don’t do an adult body good. Could you talk a little about one or more of these substances, for example miRNAs and/or nutrients such as casein or galactose?
Persistent activation of mTORC1 promotes age-dependent diseases. mTORC1 is activated by BCAAs such as leucine which are abundant in whey (14%) and casein (10%) proteins. Milk-derived microRNAs such as microRNA-148a not only promote lactation performance but also adipogenesis in humans. The microRNAs of milk are an arachaic signaling system, which explains their sequence homology between human and bovine species. They survive pasteurization and with the invention of the refrigerator were spread into civilized societies. Notably, microRNA-148a, the most abundant microRNA of milk, promotes lactation performance and milk yield and is overexpressed in high performance dairy cows.
With the selection of high performance dairy cows, pasteurization and refrigeration, civilized societies are persistently exposed to milk´s microRNA signaling. MicroRNAs control about 60% of human genes. With the introduction of bovine microRNAs into the human food chain, which are able to regulate human gene expression, humans got under gene control by another species, the dairy cow. The microRNA system of cow´s milk has the natural purpose to promote anabolism and growth of the calf, but not of human beings for life time. In contrast, fermentation, boiling and ultraheat treatment destroys milk´s micro RNA system, which explains why fermented milk products have a reduced risk profile.
4. You are probably the world’s foremost experts on the role nutrition, and in particular milk consumption, plays in the pathogenesis of acne vulgaris. Could you please talk a little about your research in this area and the link between diet and acne?
There is accumulating evidence from epidemiological and placebo-controlled clinical studies that milk consumption promotes or aggravates acne vulgaris. During the last three years, dermatological societies changed their mind and accepted the link between nutrition and acne. There are two major drivers of acne: milk and hyperglycemic carbohydrates. Both activate mTORC1. Milk consumption increases the levels of BCAAs, insulin and insulin-like growth factor 1 (IGF1), which all activate mTORC1. High glycemic food as well enhances insulin levels and provides abundant energy (ATP), which activate mTORC1. Thus, milk and sugar (regular components of Western diet) synergize in the activation of mTORC1.
5. The dermatological community, as a whole, has not yet embraced the idea that diet plays a critical role in the pathogenesis of acne vulgaris, despite the fact that this idea is very much scientifically sound. Do you think dermatologists will soon incorporate dietary interventions/strategies into their treatment repertoire?
Academic dermatology was misled by a paper of Fulton et al in 1969, which compared the effect of chocolate bars with vegetable oil bars on acne. Unfortunately, the glycemic index of verum (chocolate) and control (vegetable bars) were identical, and thus showed no significant differences in acne outcome leading to the conclusion that diet has no effect on acne.
6. Milk is just one of the many dairy products that the modern, westernized man consumes on a regular basis. How do other dairy products, such as whey protein supplements and yogurt, compare to milk with respects to their impact on MTORC1 signaling, IGF-1 levels, growth, and the development of western diseases like acne vulgaris?
There are several reports including own clinical experience that show an aggravation of acne by whey protein abuse. This is not uncommon in the body building and fitness environment. Total dairy protein consumption is related to IGF1 serum levels, which promote sebaceous lipogenesis and acne. Cheese consumption increased in Germany from 1950 to today by the factor of 5, which demonstrates excessive dairy consumption in developed countries. Notably, fresh pasteurized milk is special, because it simultaneously transmits milk´s amino acid hardware and gene regulatory microRNA software, which are closest to milk´s natural program.
7. It’s generally believed that dairy food consumption is beneficial with respects to bone strength and osteoporosis risk. However, much research, including some large epidemiological studies showing that bone fracture risk correlates positively with dairy intake, questions the validity of this idea. What’s your take on the link between bone density/osteoporosis risk and dairy food consumption? What does the evidence show?
Recent epidemiological research, especially of the Harvard group around Walter Willett (see Homepage) provided strong evidence that dairy food and milk consumption increase the risk of bone (hip) fractures in people of higher age. Furthermore, Prof. Michaelsson of the Karolinska Institute (Sweden) showed a significant correlation between the dose of milk consumption and mortality risk.
8. What types of foods would you recommend that we should eat to optimize our calcium intake? Do you think people will put themselves at risk of calcium deficiency if they cut dairy foods from their diet?
There is abundant calcium in vegetables like broccoli and mineral water (see recommendations of the Harvard Homepage of the Willett group). Important for bone health is sufficient exercise and sufficient vitamin D supply (sun light). The amount of calcium in cow´s milk is intended to promote skeletal growth of the calf, which doubles birthweight after 40 days compared to human infants with 180 days. Furthermore, skelet weights of adult cows and humans differ significantly.