Why so much hate for milk? It’s the source of life after all. Let’s explore what milk is and answer some FAQs.
300ml whole milk contains C14 P10 F10 349mg Calcium 442mg Potassium
It also contains magnesium, phosphorus, iodine, B12, riboflavin and vitamins A, D & K2.
Carbs: Lactose + galactose Proteins: Casein (80%), whey + immunoglobulins (20%) Fats: saturated, monounsaturated, and unsaturated fats such as CLA, Omega-3 fatty acids and trans-palmitoleic acid.
What is milk? Milk is a mix of water, proteins, sugars, minerals, and vitamins. Nutrient composition depends on the animal it comes from. I’m just going to focus on cows milk here as it seems the be one most under fire from mainstream media and click hungry bloggers.
First things first, as it currently stands there is no clear link between milk consumption and any diseases or health problems at a population scale level. We have a lot of research on milk and so far nothing hugely concerning has risen.
It’s got whey in it, whey is pretty cool: It’s not just for muscle building, it’s also been shown (with solid evidence) to:
lower triglyceride levels
lower blood pressure
improve the function of our blood vessels
improve insulin function
improve glucose control
sometimes lower total cholesterol and triglycerides
increase total antioxidant capacity (by increasing glutathione levels)
Not all milk is created equal. Milk from grass fed cows has significantly more fatty acids (we need these) than that of grain or corn fed cows. It’s got 2x more conjugated linoleic acid (CLA) and 62% more omega-3 fatty acids. Pretty cool huh.
Isn’t casein addictive and bad? No, casein is not more addictive than heroin. Don’t believe anything your hear on a Netflix documentary. It doesn’t get into your brain, there is a thing called the blood brain barrier that makes sure no cheese is making it’s way to your brain to wreak havoc. There isn’t enough evidence to blame type 1 diabetes, coronary heart disease, digestive upset, or your cheese obsession on A1 beta-casein.
But what about all the nasty hormones? There are hormones in cow’s milk, even in organic milk, and even in human breast milk too. There are estrogens in dairy. However as the current research stands there is no solid evidence saying these estrogens are able to enter our bloodstream or that they can negatively influence health or development when consumed in milk or dairy products. Ingested steroid hormones are broken down by the liver after absorption so are not harmful. This is why people who use exogenous steroid hormones such as diabetics and bodybuilders with low self esteem inject them rather than taking them orally, to bypass the liver. If we could take hormones like insulin orally and see effects why would we be giving diabetics injectables?
But but… what about the growth hormones? There are some dairy farmers that use bovine growth hormone (bGH) or somatotropin (bST) to increase milk production. These hormones do appear in the milk but they don’t absorb as hormones in humans, they are not biologically active in humans and never enter the bloodstream. What happens to them is they get broken down into peptides which are small bits of protein. These types of hormone are present in teeny tiny amounts (about 1/1000 of a gram per litre of milk) and there’s also that thing called pasteurisation that kills 85-90% of them anyway.
But but but… what about IGF-1? IGF-1 or Insulin-like growth factor-1 is a hormone we already have in our body, it does what it says on the tin; helps you grow. Insulin, would you believe it, it helpful for anabolism (making muscle gains) and needs to stop being victimised. If you are interested in building or maintaining muscle mass then IGF-1 is your pal. There is some concern that all this growing could cause unwanted tumour growth but as it happens consuming milk only causes about a 2-10% rise in IGF-1 (above fasting levels). All protein rich foods from BOTH PLANT AND ANIMAL sources increase levels of IGF-1. It’s not just the milk.
Isn’t it linked to cancer? Current evidence clearly indicates that regular dairy intake does not pose increased risk of several types of cancer.
Does it support bone health? Yes. It’s common knowledge that milk is ‘good for building strong bones’. The last 40 years of research supports this. Dairy consumption has been shown to improve or maintain bone mineral density and prevent or slow bone loss. Resistance training is also hugely beneficial and so pairing a healthy diet with some training works hand in hand to keep our skeletons strong as we age.
What about cardiovascular disease risk? If you are exercising regularly and eating a balanced diet, moderate dairy consumption is unlikely to put you at extra risk for cardiovascular disease or stroke. Consumption of some dairy products (like greek yoghurt and hard cheese) have actually been linked to decreased risk in some studies. Likely because the people that eat these make more intelligent dietary choices on the whole.
What if I have allergies/ intolerance? People fall on a spectrum of tolerance and digestibility to dairy that’s influenced by genetics, age, digestive health and intestinal microbiota. If you have a dairy allergy, you should probably avoid dairy. If you are lactose intolerant you can try out lactose free dairy products or just steer clear of it.
But what about the dairy industry? We made the dairy and beef industry through many years of genetic engineering for the purpose of having these nutrition options. This is going to ruffle a few feathers, but getting milk from a cow that otherwise wouldn’t exist doesn’t seem too morally reprehensible to me.
‘Humans are the only animals that drink another mammals milk’: That’s actually not true. There are birds called Red Billed Oxpeckers that perch on the udders of Impala and drink their milk. On the Isla de Guadalupe in Mexico, feral cats, seagulls, and sheathbills have also been seen stealing milk directly from the teats of elephant seals. That’s not even considering carrion birds and other scavengers. My second point here would be: yes, but humans are also the only animals to ever wear clothes, watch TVs or go into a separate room and lock the door to use the toilet.
The verdict: If you tolerate it, like it, and benefit from it then drink milk. If you don’t tolerate it, don’t like it, or feel it upsets you in any way then maybe don’t drink milk. In my opinion milk is useful and there is no other substitute for it (outside of dairy) with the same macronutrient composition.
CV disease, other diseases & general health:
Yoghurt being good:
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