Food

The Science of What an Absolute Meat Ban Can Do to Our Brains

Recent research is beginning to throw some light on whether eating meat during pregnancy impacts the development of the foetus’s brain.

Beef on the plate. Credit: melitaschuller/pixabay

Beef on the plate. Credit: melitaschuller/pixabay

“Life is a contradiction present in things and processes themselves, and which constantly originates and resolves itself; and as soon as the contradiction ceases, life too comes to an end, and death steps in.” I was reminded of this quote by Frederick Engels when I started thinking about the recent ‘Prevention of Cruelty to Animals (Regulation of Livestock Markets) Rules, 2017’ notification by the Government of India.

My own contradictions: I am a Hindu albeit a non-practicing one, I refrain from eating animals that are known to have nociceptors, and I oppose governmental imposition of any dietary restrictions in India.

So after some thought, I decided to discuss the science of meat, more specifically the effect of meat on our brains, evolution and the future, rather than analyse my own dichotomous beliefs.

We would not have been human without meat

Early on, in the six million years of human evolution, our ancestors were essentially vegetarians. A change in our dietary practices came about around 2-2.5 million years back. Research has now proven that the size of our brains increased exponentially only after we turned carnivorous. There are several reasons why meat helped us become what we are today, and much smarter than other primates like chimpanzees.

First: the vegetarian diet did not provide the energy and key nutrients as efficiently, or in as much quantity, as meat did. The brain of the modern human has a very high energy requirement. Second: the gastrointestinal tracts of early humans used to be much larger to help digest fruits, leaves and roots, and had a very high energy requirement as well. So as we changed our diets, our guts became smaller and the brains, much bigger, by preferentially receiving a higher percentage of energy from our diet. The fact that we became more adept at using tools and started cooking also helped.

Recent history and the future

Delhi University professor D.N. Jha received death threats after he published a controversial book in 2002 called ‘The Myth of the Holy Cow’. The book documented the results of his rigorous scholarly research about the dietary preferences during the Vedic times. He wrote that cows were sacrificed and beef was eaten during those times. If we are to believe him, about 30% of Indians have turned vegetarian since then.

India has the world’s highest rate of vegetarianism. In absolute numbers, it has more vegetarians than the rest of the world combined.

So humans’ recent nutritional history throws up a few questions. Did the meat-eating habit of a few thousand years back fuel further evolution of our brains? Does a meat-eating habit remain important for us humans to develop our brains even further? And if all Indians stopped eating meat for long, will there be an appreciable difference in the size of our brains as a result? Will our intelligence remain comparable to that of the others who remain carnivorous? For one, the Government of India notification seems to go beyond just beef. If strictly implemented, it may impact other meat-eating habits and even hamper the availability of other animal protein sources like milk.

The answers to these questions are less clear and not well studied. A hypothetical assessment would be that a few thousand generations of dietary practices may perhaps have an impact – rather than those of merely a few thousand years.

Recent research is beginning to throw some light on whether eating meat during pregnancy impacts the development of the foetus’s brain. As the brain slowly develops during a normal and uneventful pregnancy, it becomes more complex and mature. A recent study utilised innovative neuroimaging techniques and found that iron deficiency in mothers negatively impacted the complexity of the offsprings’ brains at birth. In other words, more normal levels of iron were associated with more mature brains at birth. Since meat is rich in iron, this study provides some indirect evidence that meat-eating may be beneficial for the foetal brain. This may be of particular significance for India, which has high prevalence rates of anaemia among pregnant women.

The potential impact of dietary restrictions on the brain and evolution is probably a blip on the radar of the present dispensation. It appears focused on foisting ideology with disregard not only for history and science but even for economics.

Jay Desai is a neurologist. He tweets at @JayDesaiMD.

  • Rohini

    I am disturbed by the attempt to create an unfounded fear in pregnant women about the development of the foetus’s brain and link it to meat, for which there is NO evidence whatsoever in that study!
    His conclusions in the last paragraph are specious, to say the least.
    i.e.,*** “Since meat is rich in iron, this study provides some indirect evidence that meat-eating may be beneficial for the foetal brain. This may be of particular significance for India, which has high prevalence rates of anaemia among pregnant women.”**
    There is NO way to arrive at this conclusion scieentifically fromt he study he has refernced..no way. Noot even with ‘maybe’ and ‘but’ or ‘perhaps’. NO scientist wirth her salt would add her name to such a conclusion from that study. Why? Because:

    The stud shows that that maternal iron intake is related to for fetus brain development. It does NOT study the effect of iron from meat vs iron from vegggies or other sources in the maternal diet
    All one can say is…Iron MUST be consumed at the required levels during pregnancy to ensure good fetal brain development. That’s it.
    The study also acknowledges its limitations: Copy – paste:
    ————————————
    “This study has several limitations. First, because of the highly technical nature of the brain assessment,** the sample size was relatively small and limited our statistical power to detect real effects**. Second, **we cannot assert true developmental effects relating maternal iron intake to newborn brain characteristics in a cross–sectional study.** We also **do not know the cognitive and behavioral correlates of our iron–related FA values and newborn brain tissue organization****, or **whether these results will generalize to pregnant adult women and their newborns.** Finally, FA interpretation presents challenges in studies of newborn infants** without knowledge of the effects of changing intra– and extra–cellular water concentration with age on FA values (34) and how variations in maternal iron intake can affect those changing water concentrations.**
    —————————-
    Gynecologists are well aware of this need for iron (obviously!! ha) and prescribe iron supplements as soon as pregnancy is confirmed. Healthy diets is important (veg or non veg, doesn’t matter, so long as it includes a lot of iron, vitamin, protein and calcium sources) though this is usually a problem for pregnant women given the nausea and aversion to many types of food/drink. Which is why supplements of all sorts are a given for every pregnancy.

  • Rohini

    W ho on earth is a ‘practising’ HIndu and what exactly does Jay Desai not ‘practice’ to make him a non-practising HIndu? In Hinduism, atheists can call themselves HIndu..so what’s all this, Jay Desai? Just askin’,…

  • Rohini

    How right you are! There is an attempt to give selective information to the public because they are relying on the inability of the general public to understand scientific subjects..for e.g, the bit on evolutionary biology leaves out the fact that the human intestine or facial and teeth structure are not suited for meat eating and that meat eating would not have been possible for humans had they not invented stone tools (to break down the meat) and cooking (to help intestines digest and absorb). It also does not mention that agriculture and a sustained supply of food was in fact most responsible for the survival and spread of homo sapiens. Many more such links in our evolution have been purposely left out to suit the ‘story line’.
    Also, since evolution is all about natural selection based on adapting to the environment, man today is clearly adapted to the environment we live in and the foods we consume. MOST importantly, traditional diets VARY widely across the world and our genetic make up is uniquely adapted in groups to be able to handle the traditioanl foods each group consumes (there is a LOT of scientific literature on the specific genes that 100s of races/ethnicities/tribes/peoples worldwide have to deal with their specific diets).
    This article is selective in what it presents and how it concludes.

  • Rohini

    Why would you want a carnivore to turn vegetarian? Stupid thing to do to arrive at a common sense conclusion…and btw, what is really wrong with cannibalism?
    Nature has shown that some species turn cannibal when they have a shortage of food or even in other circumstances. Some species do it, some don’t. Nature doesn’t conform to your human imposed false code of revulsion for cannibalism.

  • Rohini

    The fact of science is that amino acids were necessary for brain development…that is true. So, those chaps millions of years ago had no great sources of quick good quality amino acids from plants, so they discovered meat, and bingo! It helped.

    However, what the author refuses to say is that agriculture is a highly evolved and civilized construct of the human species, homo sapiens. Thanks to agriculture, we have myriad sources of the essential amino acids from plant/veggies. The discovery and cultivation of pulses and a wide variety of legumes etc are substitutes for the amino acids that meat provides.
    Its simple dietary science. But the author won’t tell you that.

  • Rohini

    Same logic applies as my previous response. Whatever the reason, when there is a shortfall of something, nature will do what it takes to correct it. What are you trying to prove with your statement?

  • Rohini

    So, no point to make. That’s what I thought.

  • Rohini

    No amount of effort will help me understand gobbledegook.