Fortified, filtered, or homogenized? Fat-free, lactose-free or full fat? Should you bother with organic?… Is bovine best? What are the reasons behind the existence of all these varieties of milk, could the white stuff really be so ‘hyperallergenic‘? This article makes use of all the relevant scientific literature and will get to the bottom of the health claims associated with this Western dairy tradition.
I got a little carried away researching this article, so it expanded to obscene proportions. Consequently, feel free to fast forward to your sections of interest:
– Milk is a Generally Nutritious Drink
– Milk is a Strong Sports Nutrition Beverage
– Remarkable rehydrator
– Calcium in Dairy is Useful For Fat Loss
– Milk’s Fat Loss Mystery Ingredient (NOT Calcium!)
– Does Milk Give You Strong Bones?
– Reduced Heart Disease and Stroke
– Lactose: Laudable or Lame?
– Milk and Cancer
– Cow Milk Allergy To Proteins
– Iron Deficiency
– Milk and Estrogen
– The Calcium is not always beneficial
– Consumption Problems With Dairy
– Bovine Somatotropin (rBGH) and IGF-1.
– A Word on Somatic Cell Quality
– Antibiotics in milk
– A Little More On IGF-1
– ORGANIC VS. NON
– FORTIFIED VS. UN-?
– WHOLE VS. SKIMMED?
– UHT vs. PASTEURISED vs. FILTERED vs. RAW?
– HOMOGENIZED VS. UN-
– GRASS FED VS. GRAIN FED
– FLAVOURED MILK?
– EVOLUTIONARY ARGUMENT
As I’m sure you’ve noticed, we are constantly bombarded with a huge variety of conflicting nutritional advice in our modern western world, and dairy produce is a typical subject. It is perhaps one of the most controversial foods, and amongst dairy, milk, in particular, sees much hype. So what exactly is the research regarding milk? Are whole milk drinkers fatter than drinkers of skimmed? Should you bother with organic? Does milk stand up to its health claims? I’ve collected as much relevant information I can find to give you the most informed picture of whether milk is indeed ‘healthy’ or not, and ultimately whether and how much you might drink, based as ever on our current understanding of ‘the nature of things’. Remember, as technology advance, we’re constantly experimenting, studying and re-evaluating.
Without further ado, here’s everything and anything of note you could ever want to know about milk… with a summary of recommendations at the end!
Firstly, what is milk exactly?
In our commercialised, humanised world it is easy to forget what milk really is. Think of milk not as another beverage for human consumption, rather, a life support cocktail for a newborn mammal. It doesn’t matter what milk you’re talking about, cows, goats, sheeps, human, they’re all made for the same reason, as an elixir of life. In order to complete its impressive task, it contains a wide variety of different ingredients all required to support the growth and development of the new life, whatever form it takes. Specifically, typical cow’s milk is broadly an emulsion of the following ingredients in the indicated percentages:
– 87% Water (Higher percentage if Skimmed)
– 3-3.5% Proteins (80% Caseins and 20% Whey)
– 0-4%Lipids (fats)
– 5%Lactose (milk sugar)
– <1%Vitamins & Minerals There’s an impressive array of these, although iron is absent.
Depending on quality and whether it’s organic or not, it also contains a certain amount of:
– White Blood Cells (Somatic Cells)
*Sometimes present in regular, non-organic milk.
Sounds good so far, what could possibly go wrong? As it happens there is a whole host of potential problems associated with humans’ insatiable appetite for milk, from the drinks production to its digestion. I’ll start with the positives, then move on to some of the potential causes for concern…
In weighing up the good vs. the bad, you might drink milk for the following reasons:
Milk is a Generally Nutritious Drink
I have just paid lip service to the fact that milk is a full source of nutrition, boasting protein, fat, carbohydrate, vitamins and minerals. Few drinks are so all-encompassing.
Milk is a Strong Sports Nutrition Beverage
There are data which suggest that fat-free milk is as effective as, and possibly even more effective than commercially available sports drinks at promoting recovery (think muscle gains and rehydration) from strength and endurance exercise. In one study, fat-free milk was shown to be a safe and effective post-exercise beverage that promotes recovery from exercise. As a result, it can be considered a viable alternative to commercial sports drinks by lactose tolerant individuals. Another study, but this time with chocolate milk, found that it improved time trial performance in cyclists when compared to a carbohydrate containing drink of the same number of total calories (think Lucozade and the like) .
For balance, another study found no difference between low-fat milk and regular carbohydrate-containing sports drinks on duration of exercise to exhaustion.
With regard to strength training, this study showed that in women, milk was an effective post workout beverage to tone muscle and reduce body fat. Just in case you were wondering whether this effect somehow only applies to women, I also found a study showing the same effect in men. How does milk do this? Could be its calcium and protein content or levels of the mystery ingredient. Read on to find out more!
Partly contained in the last point, milk is very effective in rehydration, more so than water or sports drinks, as demonstrated by this study. Another study shows the same benefits specifically after exercise-induced dehydration. How? Milk has naturally high concentrations of electrolytes and minerals which replenish those lost through exercise and aid fluid retention and when absorbed. As well as normally being cheaper than sports drinks, it packs a little extra nutrition, it should be a no-brainer for sports!
Calcium in Dairy is Useful For Fat Loss
You might have heard that dairy products help with fat loss . Well, some studies have certainly shown this, thanks it is thought (at least in part) to the calcium content. Calcium is a potent fat loss aid, but regarding the fat loss promoting effects of dairy we’re not if it’s just the calcium, or its combination with another potent ingredient which have the anti-obesity effects.
Before you start glugging milk to help lose weight, I should add a caveat which will become clearer in later sections. This is that milk is linked to increased estrogen, and also contains a sugar called lactose; both of which are linked to weight gain. Lactose is present in relatively high quantities in milk, but not in aged dairy produce like cheese and yogurt, which are still high in calcium. Equally, dairy isn’t the only source of the mineral, although it is the most well known. In fact, many other foods are also high in the calcium, so check some of those out if you’re not a huge dairy fan or have an intolerance.
On the topic of calcium, residents of less sunny parts of the world will do well to remember that they need the sunshine vitamin D to absorb the mineral, and they might well be deficient, especially over winter months when sunshine is weak and at a minimum. It might be wise to get some bloodwork done to accurately assess serum vitamin D levels, and if a supplement should be taken, how much. That said, for most people in temperate climates in the northern hemisphere, 1,000 IU vitamin D per day is a helpful but inert dosage, but you should check with your general practitioner before supplementing.
Milk’s Fat Loss Mystery Ingredient (NOT Calcium!)
A recent, 2012 Study indicated that when mice were given high doses of an ingredient called nicotinamide riboside, known to be present in milk, they burned more fat and became better runners from improved muscular endurance. The good news is this molecule may also be found in beer and other foods, but the bad news is that it is extremely small, hard to find and measure, and challenging to synthesize. It’s benefits have been likened to resveratrol, the molecule that has been giving red wine all the health fame of late (although there have been some disappointing revelations regarding resveratrol research recently). Nicotinamide riboside therefore offers some promise for the future, but as of yet its potential benefits are frustratingly unfulfilled.
Does Milk Give You Strong Bones?
It has been suggested that the calcium in milk not only helps with weight maintenance and fat loss, but also helps to develop strong bones. However it’s not just calcium that leads to strong bones, and this is crucial. In fact it is now claimed that the most important dietary components for strong bones are vitamin D which regulates calcium absorption and deposition in the body (seeing a trend in the importance of this vitamin?) , magnesium, boron and zinc, together with regular exercise. Stop focussing on calcium, as it needs to be accompanied by vitamin D (and vice versa) to have the greatest beneficial effects on bone density.
Ironically with regard to the strong bones claim by pro-milk campaigners, it is a fact that osteoporosis and associated fractures are actually highest in prevalence in countries with the highest milk consumption. However, it just so happens that countries with the highest dairy consumption are Nordic and Northern European Countries, who also have low vitamin D levels in their respective populations. Quite honestly, in my mind this reinforces the importance of vitamin D in developing strong bones, as no matter how much calcium you obtain from milk, if you can’t absorb it with the help of vitamin D, or if you absorb too much relative to your vitamin D intake, it will adversely affect bone density.
Reduced Heart Disease and Stroke
A 2009 study showed that regular milk drinkers suffered fewer strokes and were less likely to develop heart disease than those who weren’t. Perhaps this is a result of another mysterious ingredient we have to identify or study? Or is it that milk drinkers tend also to exercise more or are more health conscious generally? Give it time, and the studies will emerge with answers.
Now that we’ve dealt with the advantages, let’s take a look at some of the most obvious problems with milk…
Lactose: Laudable or Lame?
For millions of years of human history we have been breastfed as infant mammals, but after weaning we were not exposed to milk for the rest of our lives. This was the case until around 9,000 years ago, when during the Neolithic Revolution we began to domesticate and regularly milk our animals for human consumption. Thus began our history with milk, and the sugar it contains: lactose.
It should come as no surprise that this strange act, namely drinking the milk of another species, is an anthropologically recent occurrence, hence poorly biologically tolerated, right? No? What, don’t you accept the theory of evolution? Over the last few thousand years, Westerners have genetically developed lactase persistence, i.e. the ability to digest milk sugar well into later life, which has increased somewhat in prevalence across the population. Importantly, this is not a characteristic of the population at large. In fact, 38% of caucasian and as many as 95% of African populations are unable to digest lactose (lactose intolerant). So what happens when they drink milk (ingest lactose)? Normally they get symptoms such as abdominal bloating and cramps, flatulence, diarrhea, nausea, borborygmi (rumbling stomach), or vomiting.
Thankfully, modern science has provided an answer to lactose intolerance, in the form of lactose-free milk. Great! People who still display human evolutionary traits for not tolerating contra-evolutionary drinks can now enjoy the cultural mainstay that milk has become. Needless to say, whilst cow’s milk is natural in a ‘naturally created’ way, what is not really that natural, which we have touched on before, is consuming the milk of another species. Additionally it is suggested that lactose intolerance can even be overcome with regular small quantity milk consumption on a full stomach. Maybe it’s just not that bad, after all?
Another thing which we have not addressed sufficiently is that yes, lactose is a sugar. Metabolically it is little different to plain table sugar. Surprising as it is for most people, from a weight loss perspective the main problem with milk is the sugar, rather than the fat (addressed in the Whole vs. Skimmed section). Amount of fat and total calories have less of an effect on weight gain than the hormonal effect of certain foods on fat storage and energy partitioning. Despite Ancel Keys’ erroneous nutritional legacy that still permeates all too resoundingly today, dietary fat has consistently been shown not to be linked to Coronary Heart Disease, total mortality or cardiovascular mortality. An excellent book on this topic is Gary Taubes’ Why We Get Fat And What To Do About It. So cow’s milk contains the sugar lactose, which digest down into glucose and galactose. Just as what would happen if you ate a spoonful of sugar, some milk chocolate, a coca cola, or any other simple carbohydrates, the ensuing insulin release will lead to fat storage. Essentially, insulin is the hormone that makes us fat, and you stimulate your body to produce insulin mainly when you ingest carbohydrates, especially simple carbohydrates like sugar. Normal milk contains lactose, so stimulates insulin. In fact milk is a unusually insulinogenic drink based on its glycemic index, thought to be attributable to the whey protein content. Lactose in Skimmed milk contributes to 55% of its calories, about the same as soda. Interestingly, despite being lower in calories (1g fat is more than twice as many calories as 1g carbohydrate, or sugar), skimmed milk has higher lactose content than full fat because of a partial volume increase in all remaining ingredients once the fat is removed. Obviously this would make it difficult to lose weight, particularly if your genetics predispose you as being someone who preferentially stores food energy rather than burns it. As an interesting aside, when you remove cream from milk, its density increases as cream is less dense than milk, not more dense as you might assume based on appearance. When you think about it, this makes sense, after all, that’s why cream floats on non-homogenized milk!
It’s worth considering that lactose free milk still contains sugar, just in its component parts: glucose and galactose. The difference is that the work of the enzyme lactase is already done. On the other hand, fat is not at all insulinogenic (does not stimulate insulin release), but don’t think you can eat unlimited energy from fat and not gain weight! In this way, milk is avoidable from a low-carbohydrate diet perspective.
Milk and Cancer
In the notoriously flawed China Study, casein consumption was linked to cancer incidence. I would not read too much into this, because of the multitude of factors that were not taken into account within the study, and the fact that it was epidemiological, which by design cannot elucidate cause and effect.
To further discount the China Study, I found another epidemiological study demonstrating the effects of low fat milk and total dairy but not cheese and other types linked to an overall reduced risk of colon cancer. Further, if you have heard anything about a potential link between milk consumption and breast cancer, this is being seriously doubted by modern research, with some very respectable studies suggesting that dairy consumption is not unrelated but may actually lower breast cancer risk. Don’t you just love nutritional epidemiology?
Cow Milk Allergy To Proteins
In a similar fashion to the way some people are lactose intolerant, others are unable to digest some of the proteins found in milk, specifically casein. Thus a small number of the population are actually allergic to casein, but needless to say that tolerance varies. Immunologically speaking it is interesting that the molecule that we call casein is quite similar to gluten, and as result some gluten free diets are combined with casein free diets.
The problem with this intolerance comes when people don’t actually realise that they are allergic, and consume casein on an ongoing basis. It can get into their blood improperly digested and cause an immune response. Accordingly, such unfortunate people suffer low level inflammation which can lead to a multitude of problems such as mucus production, respiratory problems and digestive issues, as well as skin problems ranging from rashes to acne. Low level inflammation from milk consumption has also been linked to the antibiotic residue in milk. More on antibiotics later.
Consequently, if you are an ongoing sufferer of any of these symptoms, it might be worth trying to go dairy free for a while to see if there is an improvement. Don’t expect changes to happen over night, in the case of acne it can take several months for a noticeable change to occur.
Milk consumption has been inconclusively linked to poor dietary iron consumption. It has been suggested that, in addition to not including any iron in the first place, milk actually binds to iron in the intestines, preventing its absorption and helping excrete it. Chronic milk consumption would therefore lead to increased potential for iron deficiency. However, this theory has been questioned in various studies. It is worth bearing in mind if you are already anaemic, or have been in the past, and frequently drink milk but do not eat many iron containing foods, e.g. if you are vegetarian. Here’s a list of foods high in iron. This has only been shown to apply to cows milk, and I should stress that more research must be done before we are sure. Indeed breastfeeding infants with human milk has been shown to be important to actually avoid iron deficiency.
Milk and Estrogen
Estrogen is present in milk, especially that from pregnant cows, and when it accumulates in unfavourable quantities in men, apart from scaring the bodybuilding community (who supplement with testosterone) it can unhelpfully affect prostate cancer incidence in older men.
For male individuals seeking to be lean, estrogen (which all men have a certain degree of in their body anyway) itself has been linked to decreased lipoprotein lipase activity, translation: more potential to store and save body fat. Together with lactose content, estrogen in milk is another feather in the cap of the fat promoting effects of milk, conflicting with the fat burning effects of milk’s calcium. I knew the ‘milk+weight loss’ question wouldn’t be simple!
The Calcium Is Not Always Beneficial
What? But it can help me shed the kilos, and is good for my bones! I know, it’s tiring to hear the latest nutritional advice only to have it replaced with more, seemingly conflicting advice in the future, but the human body is absurdly complex and we build on our knowledge each year. Although dairy producers have been touting the benefits of the high calcium content of dairy for a while now, it is clear to medical science that consuming too much calcium is bad for you. We touched on the importance of vitamin D before, and the harrowing truth is that calcium reduces already low vitamin D levels in populations living at higher latitudes (sociologically these societies eat more dairy, and geographically they get little vitamin D from our main source: the sun). The issue is that there are many many downsides associated with vitamin D deficiency. It can reduce the body’s defenses against cancer and increase cell proliferation in the prostate (i.e. promote prostate cancer). Interestingly, fructose, the sugar found in fruit, has the opposite effect and increases the active vitamin D concentration, thus lowering prostate cancer risk. So gentlemen, have some berries with that yoghurt (or a vitamin D tablet)!
There was a study, although observational, that went one step further and actually linked milk consumption to prostate cancer. However, it was only low fat milk that provided this link, there was no such relationship with high fat milk. It is thought that the reason lies with the fact that US milk, like that in other countries, is fortified with vitamin D, which is fat soluble. So is the cancer risk down to people absorbing more protective vitamin D in the greater amounts of fat found in full fat milk? It certainly seems plausible. If you want strong bones my money is on proper vitamin D levels (how much you supplement depends mainly on your sun exposure, where you live, weather, time of day and skin type) rather than excessive calcium in the diet. For an iPhone app that calculates your Vitamin D levels based on location, weather and time of day, see here. Remember that you can consume larger amounts of calcium without worry so long as your vitamin D levels are high enough. Say you live in Spain or Florida.
It is thought that raised Insulin-like Growth Factor (IGF-1) levels in milk opens male hormone receptors (known as androgen receptors) in men and women, which are known to cause acne . Milk also contains the correct hormones to fit those receptors, further triggering a spread of spots. Unfortunately, IGF-1 is in all milk, whether organic, rBGH-free, grass-fed or not, though levels of IGF-1 have been found to be higher in rBGH treated milk. This is covered shortly.
Other potential causes of acne from milk include (with varying levels of reliability):
– a reaction to the milk proteins
– a reaction to antibiotics residue
Consumption Problems with Dairy
Dairy products in general have been blamed for cases of heartburn, migraines, irritable bowel syndrome, colitis, eczema, acne, hives, asthma (‘When I gave up dairy, my asthma went away completely’), gall bladder issues, body aches, ear infections, colic, ‘seasonal allergies,’ rhinitis, chronic sinus infections and more. These are attributed to milk in general so it is unclear whether they result from an as yet unidentified allergen or protein intolerance, lactose intolerance etc. Dr Mercola claims these symptoms and illnesses are not attributed to raw milk, insinuating they may result from the pasteurisation process (see below). Usually, cows milk is more problematic than others like goats milk, and consequently many people get all the relief they need from these conditions by swapping from bovine to caprinine, so to speak (i.e. drinking goat’s milk rather than cow’s).
I’ll discuss the antibiotic residue in non-organic milk later on, but it is thought that the antibiotics themselves are responsible for some of the allergic reactions to milk.
Bovine Somatotropin (rBGH) And IGF-1.
Don’t let the long name and ‘heavy’ science put you off, this is a relatively simple but essential section for US readers, and I’ve alluded to it a few times already. The context goes something like this…
In 1937 it was discovered that injecting cows with growth hormone called Bovine Somatotropin (confusingly also referred to as any of the following: BST, Bovine Growth Hormone, BGH, rBGH) extracted from cattle cadavers increased milk production in live, lactating animals. In the 1970s and 80s , it became technically possible and economically feasible to produce large quantities of Bovine Somatotropin using recombinant DNA technology.
In 1993, the FDA deemed rBGH usage to be safe, thus permitting its use in the US. What has caused so much contention in the US, the only country permitting its use, is the hormone’s effect on milk quality, and additionally but to a lesser extent, the cows welfare.
Ordinary milk contains and raises levels of a bodily growth hormone called IGF-1 in humans. Unsurprisingly for a growth hormone, IGF-1 causes the growth of cells… including cancer cells. The cancer worries came from studies indicating that Bovine Growth Hormone stimulates increased IGF-1 levels in milk, therefore increased levels in humans. At elevated levels, IGF-1 increases cancer rates in humans.
For a thorough round-up on Bovine Somatotropin from the company that produces it, Monsanto, click here. But don’t exclude episodes of deliberate bias and manipulation of evidence. Not that there necessarily is any. I’m just trying to remain objective. Want balance on this side of the argument? This ‘independent’ publication found rBGH to be absolutely worry-free for human consumption, and could not find appreciable evidence that it adversely affected cow health. Please feel free to ignore the inverted commas around independent in the previous sentence. On the other side of the coin, here’s an organic association extolling hatred for rBGH usage using a good old-fashioned conspiracy-style article.
I’ve alluded to the cows welfare under this hormone, as healthy cows produce healthy milk. Studies claim that although IGF-1 consumption from milk does not adversely affect humans, cows fare significantly worse when given rBGH. Mastitis is a bacterial udder infection leading to increased ‘somatic cell count’ (including pus) in milk. Supplementing cows with rBGH increases cases of mastitis in cattle by 25% according to and this meta-analysis. Also according to these studies the cows suffer a 40% reduction in fertility and a 55% increase in lameness; therefore animal welfare really does take a hit. In the EU, rBGH usage is said to be banned simply for animal welfare reasons. Canada independently came to the same conclusion. But do the conclusions of these studies put into question the previously claimed cancer-causing effects of excess IGF-1? Perhaps, or perhaps such effects weren’t adequately studies in these analyses. Never say never. For lack of agreement in the literature, I would always advise prudence in these situations.
A Word On Somatic Cell Count
The Somatic Cell Count of milk is essentially the number of cow ‘body’ cells present in the milk. It is an indication of the milks quality, the lower the count, the better, as most somatic cells in milk are white blood cells (a.k.a. pus) used for fighting infections. Disturbingly, this means that increased mastitis udder infections, from supplementing cows with rBGH, increases pus content in milk. I am glad I live in the UK! The idea of drinking cow teat pus doesn’t exactly appeal. All non-organic cows are fed antibiotics prophylactically to ward off infections, but once diagnosed with mastitis they are given more powerful, specific antibiotics to combat it, and are removed from dairy production. Worryingly for humans, antibiotic residue is found in the milk from cows recovering from mastitis, so it is crucial that they are left for enough time before being put back into production. The issue there is the lack of financial incentive for the farmer to do this, who might be eager to milk his cows before they are fully safe again. Given proper practise and well administered randomised testing of milk batches, antibiotics and pus in milk should not be a concern but can we trust that every single farmer’s standards are impeccable? Or that on a huge dairy farm every cow receives adequate attention. Hardly. However efficient we are, people make mistakes.
Unsurprisingly and reassuringly, in organic farming rBGH usage is banned. Just like you might buy free range eggs, therefore, American’s have an extra reason here to go organic (or ‘rBGH-free‘) with the milk. Having said this, because of a consumer backlash about the possible adverse health affects of rBGH usage in cattle, today oday only 15.2% of dairy farms, and 17.2% of US cows, are treated with rBGH.
Antibiotics In Milk
As we just touched upon, general antibiotic residue can be found in non-organic milk, forgetting cases of mastitis. The levels deemed safe are quite low and milk is frequently tested, but a US study found that 21% of milk contained above safe levels of antibiotics. Why might this be a cause for concern? Consuming antibiotics through your milk can develop antibiotic resistant strains of bacteria, which is a bad deal if we get ill from these in the future, as it means our cure is ineffective. I should add that this mechanism for antibacterial resistance is theory, and as of yet unproven in the literature.
A Little More On IGF-1
Essentially, cows milk is ‘designed’ to make calves grow. Hence, it should come as no surprise that milk naturally contains IGF-1, irrespective of whether it is organic, rBGH-free, grass-fed or not. The thing about rBGH cows is that there is more IGF-1 in their milk. Recently, Eli Lilly & Co., who manufacture rBGH, reported a tenfold increase in IGF-1 levels in milk of cows receiving the hormone. Direct from the horse’s mouth. Organic milk, anyone? . But isn’t there a difference between bovine IGF-1 and human IGF-1 I hear you ask? Apparently, their structures are remarkably similar. IGF-1 is essentially the same molecule in both humans and cows, and is not destroyed by pasteurisation. In fact, some claim that the pasteurisation process can actually increase IGF-1 levels in milk. Hmmmm…
In addition to actually containing growth hormone, whether organic or not, milk’s consumption stimulates further growth hormone production in humans, leading to still greater levels in the body (see this, and this study).What’s wrong with growing? Well the problem lies in the stimulation of growth in all cells, including cancer cells (cancer is essentially unregulated cell growth and division). Too much IGF-1 has been suggestively linked to increased cancer incidence. See this study. It is even suggested that IGF-1 can actually cause cancers of the breast, colon, and prostate, rather than just stimulate their growth should they develop. Other than cancer, additional IGF-1 has been somewhat anecdotally blamed for the early onset puberty or increased growth in children of today. To be fair, the latter his would be challenging to substantiate with a study.
But is there any evidence to the contrary? Is the milk you’re drinking giving you tumours and supersizing your children? Essentially, we have no inconclusive proof either way, but there is a school of though which claims that the active form of the additional IGF-1 in milk from rBGH treated cattle does not make it past our digestive system, as it is a protein, and effectively broken down in the stomach like any other during digestion. It’s also worth remembering that it’s hard to accurately measure hormone levels in living organisms, so treat studies questioning how hormones in foods affect our bodies with the skepticism they deserve. It could be that we don’t absorb much of the extra hormone, or even if we do that our body doesn’t use it like we think. The problem is that nothing is convincing without a thorough grounding in the literature. One study is not really that powerful.
However (un)satisfied you now feel with rBGH treated milk, the case remains that it doesn’t make hormone supplementation any less damaging for the poor dairy cows. Even if you don’t care about your health, think of the cows!
ORGANIC VS. NON-?
Moving away from US centred issues on milk, what’s the fuss with organic? Firstly let’s determine what exactly ‘organic’ farming entails that is different to the conventional approach.
Organic milk, according to the standards set by the U.S. Department of Agriculture, (DEFRA in the UK has similar such guidelines) comes from livestock that must follow these measures:
– At least 30 percent of the food they eat must be grazed at pasture during a grazing season of at least 120 days.
– No antibiotics or growth hormones may be used.
– All feed must be organic, no unapproved pesticides or herbicides used in its production.
– No meat or poultry by-products can be in the feed. These have historically been linked to the spread of mad cow disease, so the importance of avoiding them in obvious.
Seems like there is something to it, and to me the above measures appear sound and ethical. But is it all necessary? Well, despite organic was nutritionally nothing more than a load of hot air, there might be health benefits of organic milk:
– Organic milk has more beneficial fatty acids, antioxidants and vitamins.
– The practice of grass feeding the animals, an integral part of (but not limited to) organic farming (but not limited to leads to healthier animals, which makes for healthier produce. This goes for the meat too.
– Organic milk was shown to contain60% higher CLA content (beneficial omega 6 fatty acid). This benefit is likely from the grass feeding aspect of production.
So whilst there may be some nutritional benefits of organic produce, specifically organic milk, these seem to vary quite dramatically according to the study you choose. Increased CLA content is likely conferred from grass feeding, which can be provided irrespective of organic status, as it is here in the UK. This 2012 study failed to elucidate any concrete benefits of going organic in terms of human health, according to the current literature. Even if organic were not that nutritionally beneficial, that’s not the whole story. The Stanford study essentially asked the wrong question; it’s an issue not of what organic produce contains, rather of what it does not contain. For example, organic produce exposes you to fewer pesticides, which have been linked to human disease. Additionally, and of extreme importance, organic farming is less damaging to the environment; less polluting to water supplies and less destructive of farmland ecosystems.
So because of environmental benefit, and because we’re essentially not sure if ingesting pesticides designed to kill other organisms is bad for us (sounds stupid when put like that), and organic milk is certainly no worse for us nutritionally (likely offering some benefits), it seems fair to say that it is a worthwhile cause. As a health conscious, environmentally caring individual, I would go for it where your budget allows!
FORTIFIED VS. UN-?
‘Fortified’ is a word used increasingly in the world of food, but what exactly does it mean? Fortification is essentially the idea that food manufacturers will add micronutrients or vitamins to the food, in theory to ‘make it more healthy’, and help tackle nationwide nutrient deficiencies. This ranges from adding iodine to table salt to combat iodine deficiency, to adding flouride to water supplies for improved dental health.
With regards to milk, this frequently involves adding more vitamin D, which is helpful as we can’t absorb calcium without it, and milk naturally contains relatively little of the vitamin relative to its calcium levels. Additionally, there aren’t many foods you can fortify with vitamin D as it’s a fat soluble vitamin, so the food needs to be relatively high in fat (one advantage of whole versus skimmed, see below). Other than that, sometimes vitamin A is added to reduce nationwide deficiencies in the US which result in poor eye health.
But why fortify foods with vitamin D at all? As it happens, this type of fortification is very useful, but not always practised. Including vitamin D in milk and dairy is extremely helpful in countries whose populations live in less sunny parts of the world, particularly in the (Northern) Northern Hemisphere- think of the UK and Scandinavia. Our bodies can make vitamin D from cholesterol using UV light from the sun, but people in these parts of the world are most at risk of deficiency, particularly in winter due to weakness of UV exposure. Just 4 minutes spent outside in shorts and T-shirt on a bright summer’s day is often enough for the day’s vitamin D requirements, but when we don’t get enough sun we become vitamin D deficient. And no matter how long you spend outside in the winter months above a certain latitude, the suns rays are just not the right wavelength for you to make vitamin D. Also, as we have touched on before, it just so happens that the least sunny countries in the world also unhelpfully consume the most dietary calcium. Given the health benefits of the vitamin, it’s a recipe for disaster. For instance, weight conscious individuals might find this 2009 study interesting, in which Vitamin D was linked to lower body fat. Before upping your vitamin D this was an observation, and needs further study to determine cause and effect. For example, we know that calcium requires vitamin D to be absorbed, and that calcium helps lower body fat, so could it be rather that higher vitamin D levels lead to greater absorption of calcium, which leads to lower body fat levels? Effect on weight is however rather secondary in the physiological importance of the vitamin, which is implicated in cancer prevention and bone health amongst other key health issues.
In summary, if you don’t live in a part of the world renowned for it’s sunny weather, you could well be vitamin D deficient. In which case, fortified milk is a good bet to help you top up. If you live in the dark, get a good supplement too. However, watch vitamin A intake as it’s important not to overdo it, which should be hard from milk alone. Just don’t supplement that vitamin!
WHOLE VS. SKIMMED?
Here I’ll discuss the fat content of milk, referred to differently depending on where you are in the world. There’s much more to this than whole milk is higher fat therefore higher calories, so we’ll look at the benefits and pitfalls of the varying levels.
Firstly, the fat content of milk naturally varies a little depending on the breed of cow, time of year the milk is produces, weather, feed, etc. but usually whole or full fat varieties boast more or less the same fat content that milk contains when unadultered, between 3.5 and 4%. By contrast, you can get fat free milk with 0-0.5% fat or less, or semi-skimmed with around 2%. So why the options and what are the benefits?
As most people avoid whole milk in an attempt to become or remain slim, it might be worth looking at whether this is effective. i.e. Are whole milk drinkers fatter than skimmed? Although it is by no means watertight, this 2009 Swedish study found that children drinking whole milk every day were on average 4kg less heavy than other children. Amongst the overweight group, children drinking whole milk daily were less overweight. As discussed in the last section, is this due to increased vitamin D uptake, a helpful effect of the extra fat content? It’s possible, if vitamin D does indeed help with getting lean.
By numbers, semi-skimmed is most popular in the UK, accounting for roughly 63% of all sales, but why is this? Is it a mere compromise between slightly lower fat and better taste of fat containing milk? As a society we’ve been demonising fat for decades, but few prefer the taste of fat free milk to full fat. Thus it is a national, logical compromise to buy the one with a little fat for flavour, but not too much! Interestingly, the majority of studies seem to show that drinking milk in general, be it whole or skimmed, lead to improved cholesterol levels, and that drinking 2-3 glasses a day might lower risk of heart attack and stroke. Again, these are hardly concrete observations, but suffice it to say that full fat milk really is not a whole lot worse for you than skimmed. Trying to get a few puns in here somewhere.
One particular and obvious saving grace with low-fat milk, as opposed to full-fat milk, is that the former is lower calorie, so will help you stay below any calorie targets you have more effectively. The issue here is that calorie counting is in now way as helpful to the weight conscious as is carefully controlling one’s macronutrient profile (i.e. how many of their calories come from protein, carbohydrate and fat respectively). To quote nutrition author Gary Taubes, ‘Of all the reasons to question the idea that overeating causes obesity, the most obvious has always been the fact that undereating doesn’t cure it.’ Some contest that eating fewer calories just makes you hungrier, so drink whole milk and you’ll feel fuller, leading you to eat less throughout the day. More important than the fat content of milk with regard to weight loss is lactose. Essentially, lactose stimulates insulin release, and in simple terms it is insulin which promotes fat storage. Counter-intuitively, dietary fat does not stimulate insulin, so does not directly lead to fat storage in the way the sugars like lactose do. On the other hand, in weight training you are trying to gain weight, so go for the high fat option despite the indirect role it plays in body fat accumulation, as higher fat milk which has been shown to be 2.8 times more effective at building muscle than skimmed. For lack of a better explanation, I’d like to simplistically attribute the muscle growing effects to the higher calorie content.
So if you’re saving calories and have enough vitamin D, by all means stick to fat free milk. If you’re weight training or need all the vitamin D you can get, it might be advisable to go for whole milk. If you’re trying to lose weight, probably avoid milk altogether, but make sure you get some calcium and vitamin D from elsewhere.
The following are methods of preserving and decontaminating milk, again with associated controversy. Why does milk have to be so damn complicated?
UHT stands for Ultra Heat Treatment and involves heating the milk to a very high temperature, around 135 degrees celsius, for only a few seconds. This kills bacterial spores in the milk, thus preserving it for a considerable period of time, providing a shelf life of up to 6 months, unrefrigerated. That’s particularly useful for reducing refrigerated transport costs and associated effects on the environment in warmer countries like Spain. There are however disadvantages to UHT, like heating it to this extent destroys certain beneficial nutrients, such as folate, vitamin B12, vitamin C and thiamin. Additionally, the flavour and smell is affected. UHT is technically a type of pasteurisation, but milk normally referred to as ‘pasteurised’ undergoes a procedure called HTST (High-Temperature, Short-Time) treatment
Pasteurised milk as described above, called HTST, is by far the most popular form of milk available today. Typically, HTST heats milk evenly to 71.5-74 degrees celsius for 15-30 seconds, and as such is less severe than UHT. It maintains colour and flavour better than UHT, at the expense of a reduced shelf life (2-3 weeks as opposed to 3 months or more), but still kills 99.999% of the microorganisms in milk. Nutritionally superior to UHT, pasteurised milk containing up to 9 times as much folate as UHT.
So UHT and pasteurisation are great for preservation, but they do impact the milk’s composition. According to biohacker and Bulletproof Diet performance nutritionist Dave Asprey, heat treatment kills of the beneficial probiotics in the milk, denatures milk proteins, and turns lactoses into beta-lactoses that spike insulin more severely.
Other than affecting the nutrient status of milk, another downside to heat treatment is that when the carbohydrates in milk react with the proteins at high temperatures, small amounts of toxic compounds may be formed. The resulting impact on your health in uncertain. Granted it is unlikely that they are acutely pernicious, as us Westerners have been drinking huge quantities of pasteurised milk for a number of decades now. However the case remains that they may adversely affect our health in more undetermined ways. The point is we can’t know without the relevant studies, so it’s best to avoid pasteurised milk if you can, opting instead for high-quality, local, raw milk.
As heating damages the nutritional properties of milk, you might wonder if there is a method to kill bacteria in milk without the damaging effects of heat treatment. There is, and it’s a high tech filtration method called membrane filtration which some dairies now use instead of pasteurisation. Done carefully, filtered milk is possibly preferable to raw.
There’s no doubt: nutritionally, raw milk is best. The disadvantage is potential contamination from dangerous bacteria, leading to the product’s illegality in some US states. Raw milk is legal in the UK, but its sale and quality are tightly regulated, such that consumers can only purchase it from the farm’s gates, and health warnings must be displayed on packaging. Regarding the benefits of raw milk, Dr.Mercola has this to say in his article: The Real Reasons Why Raw Milk is Becoming More Popular:
‘While it is certainly possible to become sick from drinking contaminated raw milk, it is also possible to become sick from almost any food source. But it seems that raw milk has been unfairly singled out as a risk, when only a very small risk exists… Raw milk is an outstanding source of nutrients including beneficial bacteria such as lactobacillus acidophilus, vitamins and enzymes, and it is, in my estimation, the finest source of calcium available…People who have been allergic to pasteurised milk for many years can typically tolerate and even thrive on raw milk.’
Dr. Frank Lipman of the Eleven Eleven Welness Center in New York also anecdotally claims that raw milk is less allergenic than the processed variety.
So raw milk might have a stronger nutritional profile than the pasteurised variety, but raw requires the milking farm to be immaculately clean which is a difficult task on an industrial level. As a result, local raw milk from a small, well-managed farm is worth trying, industrial raw milk could be risky. Finally, if you opt for raw, drink it as freshly as possible, because it spoils significantly more easily, even at cold temperatures.
HOMOGENIZED VS. UN-?
Given that most people don’t grow-up on a farm, this is one area which escapes a few people today. In milk that has not been homogenized, the fat it contains will naturally settle at the top when it is left to stand. What homogenization does therefore is distribute the cream (milk-fat globules) evenly throughout the milk so this separation does not occur. So what’s the problem with that? It makes it look more appealing, and stops you having to shake it before you have some to redistribute the fat. Again, whilst seemingly innocuous, insufficient scientific study has been done into the health implications of homogenisation. In essence, facts don’t stand until scientifically established.
In fresh milk each lipid globule is surrounded by apical plasma membrane from the mammary epithelial cell. In milk homogenisation the fat globules with their globule membrane are broken up into many new small lipid droplets with just a small fragment of the originating membrane. This only has potential health implications, and nothing serious appears to have come of it as of yet. One could argue, like with pasteurisation, that we’ve been conducting a rather large experiment for decades in Western society as we ingest huge quantities of homogenised milk to seemingly no ill effect in the general population (salut, epidemiology). Equally, maybe homogenization does entail adverse health effects, but they are cumulative, very subtle, or only affect a significant minority. For fear of succumbing to the bad science of epidemiological studies, we’ll have to hold out on this one. For now, as you might hope, it appears that homogenized is just fine.
GRASS FED VS. GRAIN FED
I should point out that this section really only affects North American readers. UK cows are largely fed a diet of fresh grass as standard, and dried grass in the winter. Wtih regard to the health of the animals, it’s clear from studies that grass fed cattle are healthier and leaner animals that produce healthier and leaner produce. This study also proves that the health benefit is indeed transferred to those who eat this superior produce. Needless to say it is likely that the animals have a better quality of life. Studies aside, does it not make sense that a healthier animal makes for healthier animal produce? Grass finished is better than only grain fed, but look for cattle produce that is grass fed for as long as possible. This is sometimes difficult or impossible to determine from the food labels, so do a little research on the farm it came from. It might surprise you! The reason cows are grain fed in the States is due to the government-subsidised overproduction of corn. This overproduction is likely the underlying cause of America’s obesity problem, but that’s a story for another day.
Schools in America offer children flavoured milk, often chocolate. The only fundamental difference here is sugar content, with chocolate flavoured milk adding additional sugar to the children’s diet, therefore despite the improved taste, it is certainly less healthy.
In theory, the above analysis is all well and good. But analysing milk like this is missing an important point. Biologically speaking, are we even supposed to be drinking milk? The answer is an overwhelming ‘no’ after childhood. And that goes for milk of any kind, even human. Anthropologically, Mark Sisson has written a good, critical article on dairy consumption and how it progressed to the modern day. Given that we’ve only eaten dairy for 9,000 years or so, we only used to receive mother’s milk as an infant, then historically progressed to be dairy free for the rest of our lives. We’ve evolved therefore not to continue to consume milk of any kind after infancy, let alone habitually consume that of an animal that is morphologically quite different to us throughout our lives.
Before you breathe a sigh of relief that the potential dangers of dairy have finally waned, I have deliberately left out heart disease from the list, as frustratingly, epidemiological studies have linked milk consumption to increased as well as decreased risk of cardiovascular disease, so that particular area is currently inconclusive.
It’s tempting to make the case not to drink milk based on the evolutionary argument, plus the fact that the list of problems appears longer than that of the benefits. Of course, that could be down to my skewed research, or personal, educational or cultural biases. Perhaps the best thing is to take a reductionist approach and simply decide if you’ll drink cows milk or not. Period.
After all this research can we say that milk is healthy? Or is it just ‘not unhealthy’? The point is that it varies depending on our genetics. Using BGH is a bad idea given the increased incidence of mastitis in cattle, and the IGF-1 content of the milk they produce. As such, milk itself is not the problem if you’re lactose tolerant and handle the hormones unproblematically, what is problematic is milk produced intensively under strenuous conditions, where output is put above absolute human health and animal welfare. North Americans might want to avoid milk from rBGH treated cows and get grass fed. Buying organic is wise if your budget allows it, and raw milk may be an even better option if you can guarantee the cleanliness of the source. Otherwise, you can’t really go far wrong buying raw milk of some fat content, preferably organic, fortified if you need it, and definitely rBGH-free if you’re in the US. And for goodness sake fat-free isn’t necessarily better- indeed it’s worse if you’re vitamin D deficient or trying to gain muscle.
As for fat loss… there are clearly conflicting ideas here, on the one hand lactose is present in all milk, independent of the fat content (even lactose-free still contains sugar!), whey proteins are highly insulinogenic, milk is not without caloric load and can promote estrogen production, on the other hand dairy contains calcium which is proven to help with fat loss, as well as unknown quantities of nicotinamide riboside which might additionally help burn fat. However, the fact that studies have linked dairy consumption in general to better weight management and reduced fat tissue might lead us to believe that despite the lactose and estrogen, milk does help with weight loss. Perhaps it has a strong, hitherto undescribed effect on satiety? Perhaps those seeing reductions in weight with dairy might be consuming it as opposed to much less healthy, sugar-laden alternatives, and as such it is not the dairy, rather the exclusion of less healthy products that leads to their noted fat loss? As ever, more study is needed to really determine the weight loss attributes of milk and dairy produce. Since the jury is out, if you’re watching your weight it would be best to avoid milk for the insulin-spiking effects
Whatever you have decided, the current trend is that milk sales are declining. In the US milk consumption has reached its lowest levels since 1984. Whilst no one truly knows what is causing the decline, it is thought to be due to increasingly strong sales of new drinks such as energy drinks, sports drinks and protein shakes, but also bottled tea and humble old water, rather than any inherent problem with the white stuff.
What do I do? I rarely drink milk at all, even post-workout. If I do, I opt for local, whole, organic, raw milk. I would get milk fortified with vitamin D wherever possible, and prefer filtered to pasteurised if buying the industrial variety.
Any clearer? I fear I may have raised more questions than I set out to answer!
If you’d like an alternative, why not try one of the following? Avoid products with added sugar, and realise that some of these come with their own health concerns, such as soy milk, which harbours hormone disruptors and might not be good for your teeth (see this and this article). The following options are non-bovine animal or plant-based alternatives:
Non-bovine Animal Milks
– Goat’s milk (widely stocked in supermarkets)
– Buffalo milk (now stocked in British supermarkets)
– Camel’s milk (supposedly very well tolerated, good luck finding it!)
– Almond milk
– Cashew milk
– Coconut milk
– Hazelnut milk
– Walnut milk
– Hemp milk
– Sesame Seed milk
– Sunflower seed milk
– Soy milk
– Lupin milk
– Pea milk
– Peanut milk
– Oat milk
– Rice milk
– Rye milk
– Quinoa milk
– Spelt milk
– Einkorn wheat milk
And that concludes things. If you got this far, thanks you for reading!
Have I missed something? Do you disagree? Have your say, leave a comment.
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