In recent years, the consumption of milk has become a controversial topic. The world seems to be divided into two camps: those who strongly advocate the health benefits of milk and assert that it's an essential part of the human diet; and the other side, which vehemently disagrees, claiming that milk has no nutritional value whatsoever and does more harm than good.
If you're on the fence - or just wondering what the big deal is about that innocent glass of white liquid - keep reading.
We're the only species to drink breast milk as adults.
Think about it: Humans are the only species on Earth who, after infancy, digest breast milk--that too, of another species. As babies, humans, like any other mammal species, produce lactase, an enzyme that helps break down lactose (the sugar found in milk). For most other species, lactase production slows down once the baby starts to grow. Yet, somewhere in the course of human evolution, there was a mutation in the lactase gene, which led to lactose persistence--that is, the ability to digest milk as adults. However, several studies indicate that a large percentage of the world's population continues to be lactose intolerant. You can look at this two ways: One, humans were never meant to consume milk as adults in the first place; or two, we are evolving into higher, milk-drinking beings. Science offers no clear-cut conclusion to this yet.
Pasteurized milk is not the best or only source of calcium.
Clever advertising through the years has reinforced the belief that milk is a source of calcium essential to our diet--and our bones. But many experts argue that we can do just fine without it. Harvard nutritionists David Ludwig and Walter Willett are among the forefront, saying that "humans have no nutritional requirement for animal milk." While a lay person might equate milk with calcium, milk also contains animal protein, the digestion of which requires calcium. So, if you're a non-veg milk drinker, you might actually be using more calcium in digestion than you're storing to strengthen your bones. On top of this, milk is not as calcium-rich as many believe. For example, the American Academy of Pediatrics recommends the following calcium intake for children:
- 500mg per day for children aged 1 to 3 years (~ 2 glasses of pasteurized milk per day)
- 800 mg per day for children aged 4 to 8 years (~3 glasses of pasteurized milk per day)
- 1300 mg per day for children aged 9 to 18 years (~ 5 glasses of pasteurized milk per day)
There's no doubt that's a lot of milk. Some nutritionists suggest instead that leafy greens, beans and nuts are a more reliable source of calcium. Check out this list of non-dairy foods high in calcium for alternatives to milk.The milk we drink today is not necessarily pure.
In 1998, India surpassed the US to become the largest milk producing nation in the world, owing to the success of Operation Flood, a 1970 project of the National Dairy Development Board (NDDB). Amul, India's largest dairy cooperative, was at the centre of the movement, which helped reduce seasonal price fluctuations of milk and generate employment and regular income for millions of Indians. But there's another side to this story that one doesn't read about in history books.
To meet the growing demand for milk, cows are artificially and continuously stimulated for lactation through injections of Oxytocin, a synthetic form of a natural hormone that has been banned for use on animals by the central government--but it is still used commonly, though illegally. The extent to which Oxytocin is found in the resulting milk supply is not fully known, though the hormone's general effects on humans are: "Oxytocin adversely affects growth hormones, especially in females, because of which minor girls attain early puberty," Dr Rahul Kumar, a pharmacologist from Chhatrapati Shahuji Maharaj Medical University in Kanpur, UP, was quoted as saying in a 2012 Times of India report. Scientists continue to study the extent of Oxytocin's - and milk's - effects on puberty onset.
Most unpasteurized milk is contaminated--even after you boil it.
Packaged milk in India is synonymous with pasteurized milk, which means an assurance of quality and hygiene--though, say some, at the cost of nutritional benefits. Unfortunately, raw, unpackaged milk sold by doodhwallahs isn't the answer. The first National Survey on Milk Adulteration, by the Food Safety and Standards Authority of India, in 2012, revealed an alarming trend: "Most urban Indians drink contaminated milk, with 70 per cent samples containing anything from starch to detergents and bleaching agents to fertilizers." Boiling raw milk at home is a common way of killing the bacteria in milk, that is, pasteurizing it--but boiling doesn't solve the problem of other contaminants.
So while science is still looking into many of issues above, the one fact to emerge clearly from this debate is that there's a lot more to a glass of milk than you might imagine. At the end of the day, moderation in everything is generally the best way to go in life. We imagine that applies to drinking milk, too.
This post originally appeared on The Swaddle.