Got Milk? Is Dairy A Good Choice For Humans?
This is a good question and (spoiler alert!) one that doesn’t really have a definitive answer.
There are many arguments for and against consuming dairy products and it probably comes down to whether you have an intolerance or not as to your choice in eating or drinking dairy. It is probably important, however, to be mindful of the fact that humans are the only creature on earth to continue consuming milk after childhood – and also the only creatures that consume the milk from another species.
Interestingly approximately 75% of the world’s adult population is dairy intolerant, which means that they have an inability to break down the milk proteins. Dairy intolerance can be a reaction to lactose, casein or whey. When we are born we produce a digestive enzyme called lactase, which enables us to break down lactose in our mother’s milk. Lactose is the natural sugar contained in milk. As we pass through childhood, many of us lose this ability resulting in digestive issues such as abdominal pain, bloating, diarrhoea, gas, and nausea.
Casein is a protein found in dairy, responsible for giving milk its white colour. A casein allergy or intolerance occurs when your body’s immune system mistakenly thinks the protein is harmful and inappropriately produces allergic (IgE) antibodies for protection. Symptoms include skin reactions such as hives, a rash, or red, itchy skin, nasal congestion, sneezing, runny nose, itchy eyes, coughing, or wheezing. Whey is another protein and is generally less problematic, however those with lactose intolerance may be likely to have an issue with whey.
Another complication with milk proteins is that they are so similar to other antigenic proteins, such as gluten, that they cause cross-reactions (this is particularly common with the casein protein), so if you have gluten immune activity, you are very likely to have an issue with dairy.
Different types of dairy have different types of casein (and other proteins like whey) in varying amounts. Each type of protein found in dairy affects our digestion differently (although some people are sensitive to all of it).
The Difference Between A1 & A2 Milk
There are 2 different types of casein in milk; A1 beta-casein and A2 beta-casein. A1 milk is found in cows that originate from Northern Europe such as Friesian, Ayrshire, Holstein and British Shorthorn, whereas A2 milk comes from cows that originate from southern France and the Channel Islands. Studies suggest that consumption of A1 type can cause gastro-intestinal symptoms similar to those of lactose intolerance, whereas consuming A2 type does not appear to cause, or worsen, these symptoms, even in those people who are lactose intolerant.
Cow’s milk, which is the most commonly consumed milk, comprises 3.3% protein, of which more than 80% of the protein is casein while the rest is whey. Sheep and goat milk are generally thought to be better for our health because although they do contain casein, they contain far less A1 beta-casein, the most inflammatory casein found in milk, and more A2 beta-casein, the easier-to-digest form of casein. So, although there are cows that are specifically bred for their A2 beta-casein content, this is not the case in general milk that is purchased from the supermarket and local shops.
Another reason for the poor digestibility of dairy is the process of pasteurisation. So, for example, many people have issues with pasteurised milk, but not with raw dairy.
The Process Of Pasteurisation
Raw milk is collected from farms daily and taken to dairies by tanker where it is then heat treated at a variety of temperatures to kill any bacteria (which, by the way, is more likely to be beneficial than harmful to health) and increase it’s shelf life. The lowest temperature is used in pasteurisation and the highest is used in ultra-high temperature (UHT). Most milk in the UK is pasteurised.
After pasteurisation, milk to be sold as liquid milk is separated from its cream in a centrifuge. Once the cream has been separated, what is left is skimmed milk. The cream is then blended back into the skimmed milk in measured amounts to produced whole milk – 3.3% fat (although whole milk would actually be over 4% naturally) and semi-skimmed milk – 1.7% fat. Or kept as skimmed milk without adding any back in. Excess cream is then sold as cream or used to make butter.
During the blending process the fat globules in the cream are usually broken up and dispersed throughout the milk to give the finished product a more uniform texture. This process, called homogenisation, also prevents the cream from rising to the top. Homogenisation passes milk through a fine filter, reducing the size of fat globules by a factor of 10 or more. Problems arise when protein molecules become attached to these smaller fat globules, allowing the proteins to bypass digestion in the stomach, which may lead to their incomplete digestion and subsequent allergic reactions. Whole milk in supermarkets is homogenised.
Low Fat Milk And Health Issues
What we should remember is that fat is a natural constituent of milk and is there for a reason. Vitamins A and D are valuable nutrients contained in milk, both of which are necessary for the uptake and use of the calcium and protein elements in milk. Without these vitamins, milk protein and calcium are more difficult to absorb and can even become toxic to the body. And, because these vitamins are fat soluble, without the fat the vitamins are not present! Stripping the fat from milk also removes anti-cancer components such as conjugated linoleic acid (CLA).
Low fat milk has been linked to various health problems:
- Prostate cancer – the risk is higher ONLY with low fat milk, not whole milk. Whole milk may actually protect against prostate cancer.
- Increases women’s cancers.
- Linked to infertility in women.
- Linked to acne.
- Linked to coronary heart disease.
- Weight gain
This study observed that higher intakes of high fat dairy were associated with LESS weight gain, whereas higher intakes of low fat dairy were significantly associated with becoming overweight or obese. Yes, you read that correctly – the exact opposite of what we have been told for years!! If you want to consume dairy products, make sure they are full fat.
Some nutritionists are of the opinion that dairy is not actually a food for humans since it is primarily a food for growing animals. This may also explain why dairy can be problematic for some people as far as weight gain is concerned, as it is nutrition specifically designed in nature for growth. Once we are past childhood we no longer require foods that promote growth in the same way. Evolutionarily we do not need to consume dairy for optimal health. However there are purported benefits from consuming dairy, so let’s take a look at some of them.
Benefits Of Dairy:
- Vitamin D
- Riboflavin (Vit B2)
- Vitamin B12
- Vitamin A
- Vitamin B1
- Vitamin B6
- Vitamin K2 (this is particularly high in grass fed cows) which is important for bone and heart health
- Omega 3 fatty acids – particularly in grass fed cattle
- Conjugated linoleic acid (CLA) – amounts depend on the cows diet
Ancestral Health And Dairy Consumption
Weston A Price, a dentist in the mid 1900s, travelled the world in order to discover what sort of diet made humans have healthy teeth, gums and facial structure. What he discovered was that as long as every different culture was eating their original, traditional diet, they did not have any issues such as cavaties, gum problems and had amazingly symmetrical bone structure and no jaw problems. As soon as the same people (or those from their communities) strayed from their traditional diets and started to eat westernised foods, they got tooth problems such as cavaties and bleeding gums, and within one generation the facial structure and jaws were already starting to decline. Interestingly, the doctors he came into contact with along his travels also noted that those people who ate their traditional foods had no diseases of civilisation such as obesity, diabetes, heart disease, cancer, and once they started to eat a western diet these issues became commonplace.
Weston A Price noted that those who were eating dairy as part of their traditional diets did not suffer from any of the problematic conditions and diseases, but it is important to note that they were consuming raw, full fat dairy, not the commercial, pasteurised, homogenised dairy we are generally consuming today. Indeed there are studies showing that people who consume raw dairy are less likely to suffer from allergies generally than those who consume pasteurised dairy.
Problems With Dairy
Dairy milk is a glandular secretion from another species, which is designed for growing a baby animal and is different from human breast milk. As humans we only drink milk from our mothers for the first few years (and many for far fewer than that – a few months perhaps). Again, human breast milk is designed for optimal growth and contains growth factors such as vascular endothelial growth factor, hepatic growth factor, epidermal growth factor. The question we should perhaps be asking is whether we still need to be consuming something intended for growth once we become adults? (Unless you are a bodybuilder and then you might benefit from it!)
Dairy can be responsible for many unwanted conditions such as:
- Lactose intolerance
- Casein intolerance
- Weight gain
These problems may, indeed, be linked to consumption/overconsumption of other foods that are cross contaminating with dairy produce. Gluten, for example, is a very similar protein to lactose, and those with a gluten intolerance often find that they are more susceptible to issues with dairy. If you have intestinal permeability (leaky gut) then you will be very likely to have problems digesting dairy products.
Allergies, asthma, hay-fever and skin problems, which have been increasing in the last 30 years or so amongst children drinking shop bought, processed milk, are rare in children drinking raw, whole, unprocessed milk straight from the farm. And the timing of exposure to raw milk has been shown to be critical, in that children exposed during the first year of life demonstrated the greatest protective effect. Allergic reactions and intolerances tend to be caused by pasteurised, processed milk from large herds crowded into barns receiving hormones and antibiotics.
Unfortunately we aren’t allowed to buy raw milk in Scotland because of the suggested risk of brucellosis. However, studies have shown that the risk of brucellosis is very low in small herds, increasing as herd size goes up. The nutrition that the animals receive is also very important so that small, grass-fed herds with appropriate supplemental feed, together with regular testing, hygienic conditions and refrigerated trucks all contribute to producing healthy, clean raw milk.
Before the agricultural revolution humans rarely drank dairy. The Maasai tribe in Kenya are one of the exceptions as they subsist on milk, blood and meat from their cattle. They are an incredibly healthy population with no diseases of civilisation (where their traditional diet is consumed).
What About Other Alternative “Milk” Products?
There are many different milk alternatives on the market, but unfortunately most of them do not contribute to good health. A great many have a long list of ingredients, including preservatives, sweeteners and fillers, which I would recommend staying away from.
There are lacto-free milks available, however unless one is intolerant to dairy, there is not really any reason to drink lacto-free milk. And, indeed, some of the lacto-free products may contain other dubious additives that you would be better off avoiding. And lacto-free milk may still contain casein and whey – which would still cause problems in some individuals. However, if you like dairy products then I would suggest that these are far healthier than the alternative options such as almond, hazelnut and, particularly, soya “milks”. These contain additives and are high in Omega 6 fatty acids, which are pro-inflammatory.
In human and rodent studies early exposure to oestrogenic compounds has been demonstrated to affect the reproductive system. In this study girls fed soy formula had altered DNA methylation in vaginal cells. A review looking at various phyto-oestrogens and their potential role in negative effects in the development of sexual and reproductive function, the immune system, neurobehavioural development and thyroid function found that results are conflicting. A high aluminium content of soy formula has been thought to cause problems, particularly in premature babies, because as well as potential neurotoxicity alumiunium competes with calcium for absorption leading to the possibility of osteopenia, which has been documented in 32% of 125 premature babies that were fed soy formula. Additionally, phytates contained in soy may impair absorption of vitamins and minerals. Isoflavones contained within soy have a molecular structure similar to oestradiol, a female hormone, and exert an oestrogenic activity in the body, and although different brands may have different amounts, it has been calculated that the average intake by an infant can be as high as 11mg/kg body weight, which is significantly higher than the amount required to exert hormone effects in an adult and also significantly higher than babies and infants who are breast fed or given cow milk formula.
“As they have a chemical structure similar to the hormone estrogen, sugar-free isoflavones can bind to both estrogen receptors (ER) α and β. However, its binding and transactivation are much weaker than that of oestrogens. Moreover, binding occurs preferentially to ERβ, in contrast to estrogen, which binds to and transactivates ERα and ERβ equally. This difference can have relevant clinical importance because the two ERs have different tissue distributions and functions and, when activated, can have different and sometimes even opposite physiological effects. ERα can be mainly detected in the mammary glands, uterus, ovaries (thecal cells), bone, testes, and epididymis, prostate (stroma), liver, and adipose tissue. By contrast, ERβ is found mainly in the prostate (epithelium), bladder, ovaries (granulosa cells), colon, adipose tissue, and immune system. Both subtypes are markedly expressed in the cardiovascular and central nervous systems. The preference of isoflavones for ERβ is the primary reason that isoflavones are seen as capable of having tissue-selective effects. However, phyto-oestrogens have several other ER-independent functions, including the alteration of epigenetic marks and the inhibition of oestradiol, which can play a role, at least theoretically, in conditioning normal sexual development and reproductive function. Finally, phyto-oestrogens affect T3 and T4 synthesis by inhibiting thyroid peroxidase (TPO). Moreover, they interfere with the absorption of administered thyroid hormone”.
Animal studies investigating phyto-oestrogens and reproductive health date back more than 50 years, with cows and sheep that grazed on red clover, which is rich in isoflavones, becoming infertile. Similarly, cheetahs in captivity fed on soy-based diets were also discovered to be infertile. If these findings are having effects on babies and children fed with soy based formula, it is more than likely that adults consuming soya milk may also experience similar issues.
Almond milk can also have disturbing health consequences. Almond milk is generally thought to be a healthy alternative to cows milk (as is also almond flour compared to wheat flour), but almonds are very high in oxalates. Dietary oxalate is plant derived and binds to calcium in the stomach during digestion and exits the body via the stool. When oxalate does not bind to calcium it leaves the body in the urine. Eight out of ten kidney stones are calcium oxalate, formed by fragmentation when there is too much oxalate and not enough liquid in the urine. A study showed 3 three children who all presented with kidney stones and hyperoxaluria, which was found to be related to their consumption of almond milk. Once they stopped drinking it, all their symptoms resolved.
A better dairy alternative is coconut milk, (provided that you can find one that does not contain preservatives!). Although they are classified as a nut, coconuts are technically a fruit, and so do not present allergy issues like other nuts. A coconut allergy is very rare. However, they do contain fermentable carbohydrate and so may cause some people gastric distress such as diarrhoea or constipation, and may contribute to symptoms of IBS.
Coconut milk has many purported health benefits such as:
- Weight loss – coconut milk contains medium chain triglycerides (MCTs), which are known to help aid fat loss. MCTs are not stored in the body but are utilised immediately for energy. MCTs have also been linked to an increase in insulin sensitivity, which can promote weight loss, particularly within a low carbohydrate protocol.
- Gut Health – MCTs have been associated with better gut health and a balanced microbiome, which, in turn, has been linked to a reduction in obesity.
- Heart health – particularly when used within a low carbohydrate diet as the high fat content helps to contribute towards a more ketogenic profile. Saturated fats have long been maligned as the villain in heart conditions, however this is now being proved to be not the case. You can read more about fats here.
- Immune system – coconut contains lauric acid, which contains both anti-inflammatory and anti-microbial properties and has been shown to boost immune health. Lauric acid can effectively inhibit the growth of certain pathogens such as Staphyloccocus aureus, Mycobacterium tuberculosis and Streptococcus pneumoniae, although this research was looking at coconut oil as opposed to coconut milk. There is also some evidence to suggest that lauric acid may inhibit cancer cell growth.
Coconuts also contain a variety of vitamins and minerals including:
- Vitamin C
And many brands are often fortified with Vitamins A, B12 and D2
So, as always, it comes down to n=1 – what works for you may not work for the next person. Finding out whether you are sensitive to dairy involves an elimination process, taking out dairy products for at least one month and then slowly re-introducing certain products and seeing whether you suffer from any deleterious symptoms. Sometimes these can be difficult to detect if you don’t experience very definitive symptoms.
On a personal note I suffer from gastro-intestinal issues such as lower abdominal pain if I consume regular dairy, but not when I consume raw dairy – however my smell and taste (which returned after a 20 year absence when I started eating a carnivore diet) diminishes when I eat or drink it, which would suggest that even raw dairy contributes to intestinal permeability, despite not experiencing any gastric symptoms. So, without the fact that my sense of smell and taste becomes weaker, I wouldn’t actually know that even raw dairy was contributing to a leaky gut. I do, however, have gluten intolerance, so perhaps it shouldn’t come as a surprise that even raw dairy could be problematic. Needless to say dairy is not part of my diet.
How does dairy affect you? Your thoughts and comments, as always, are very welcome!
It was really interesting to hear your take on this. There is a lot of grey area surrounding whether we should be consuming dairy, so it was great to read a piece which really breaks the argument down. Similar to you, I have to be careful about regular lactose intake otherwise I get stomach cramps as I suffer from IBS. I definitely agree it is about listening to your body and figuring out what is right for us as individuals. 🙂
Thanks for your comment Gemma. It is a much debated topic and there are definitely arguments for both sides. I am glad you have worked out what is right for you! 🙂
Me too! Thank you 🙂