Does red meat make you smarter?
For the record, I'm not a vegetarian and I happen to think that meat is a valuable source of nutrients. However, when I see advertisements that imply meat eaters are smarter than vegetarians, I see red.
Actor Sam Neill has previously spruiked for Meat and Livestock Australia (MLA), running the line that humans developed their unique brain size and intelligence by eating red meat. Sam's latest campaign tries to convince Dennis, an orang-utan, that red meat is an ‘amazing food' that could help his brain perform everyday activities such as thinking clearly, concentrating, remaining alert - and even staying happy! To demonstrate the happiness, Dennis and Sam ride their bikes and dance together under the trees. I suspect poor Dennis may have been better off in his forest with his bananas!
From a scientific perspective, these red meat campaigns run on decidedly shaky ground, and vegetarians and those who choose fish and chicken over red meat can feel justifiably insulted by the unfounded implications.
Sam Neill tells us the brain connection is all due to five nutrients. He spells them out for us.
1: "Iron: wonderfuel for brains"
MLA correctly notes that iron's major function is to carry oxygen to cells so they can produce energy. They extrapolate from that to imply that since the brain needs lots of fuel, it must need red meat to supply iron.
Fact: Every cell in the body requires energy. Iron is needed for making haemoglobin, the red pigment that carries oxygen to cells, but even the most brilliant of brains doesn't know (or care) where its iron comes from. The iron in seafood, poultry, legumes, vegetables or grains will do nicely. It's also worth noting that the iron in red meat is a prime suspect for why a diet high in red meat is related to many problems, including a higher risk of colorectal cancer.
Verdict: misleading
2: "I Zinc therefore I am"
MLA correctly notes that zinc is a vital part of brain cells and assists in growth and repair.
Fact: Zinc also helps growth and repair in the skin, liver, pancreas, kidneys, eye and the prostate gland. Zinc deficiency occurs in some regions of the world where people have very little food and even less food of high nutritional quality. It is rare in Australia (except in chronic alcoholism), probably because zinc is widely distributed in foods. The top sources - by far - are oysters and mussels. But you'll get plenty from any other kind of seafood, or chicken, legumes, rolled oats and other cereals, dairy products and nuts.
Verdict: misleading
3: "Omega-3s: mega brainy"
MLA is correct to note that omega 3 fats contribute to the structure of the brain, although they didn't add that these fats are most important during pregnancy and infancy.
Fact: There's a family of omega 3 fats. The main one in the brain is DHA (docosahexaenoic acid), found in fish and all Australian seafood. Red meat contains DPA (docosapentaenoic acid) - probably useful, but under-researched. However, DPA is only found in the meat of animals that graze on grass - grain-feeding doesn't cut it. Studies where pregnant women and babies have been given supplements of DHA show no extra cleverness. But one study did show that brainier kids were more likely to choose a vegetarian diet!
Verdict: misleading
4: "Amino acids: food for thought"
MLA is correct that meat contains amino acids - they're part of all proteins.
Fact: MLA told me they use the term ‘amino acids' rather than protein, because amino acids are part of neurotransmitters in the brain. Actually all protein must be broken down to amino acids before it can be used anywhere in the body. Australians don't suffer from protein deficiency and the brain has no idea if amino acids come from meat, milk or muesli.
Verdict: misleading
5: "B12: the B in Brain"
MLA correctly notes that vitamin B12 is needed for electrical impulses to be transmitted along nerve fibres.
Fact: Vitamin B12 is supplied only by animal foods, but chicken, fish, milk, cheese, yoghurt or eggs can supply it. Dennis would get it from the insects on his favourite fruit.
Verdict: OK
MLA says that if we don't get these five critical nutrients the "brain can feel the strain". Perhaps MLA thought we weren't smart enough to digest the fact that the brain needs many more nutrients than the five Sam discusses. And you don't need to eat red meat to get them.
A note for vegans
For those who consume no animal foods, a lack of vitamin B12 is a very real possibility. Too little of this vital vitamin can lead to permanent defects in the nerves that service the spinal cord. The body can store enough vitamin B12 for up to five years, so many people who eat no animal foods feel fine for some time. Sadly, by the time they discover the deficiency, the damage is done.
The options for vegans are:
1. Use soy products with added vitamin B12.
2. Take a supplement.
Plant foods that claim to contain vitamin B12 - such as comfrey and spirulina - have a form of the vitamin that is not absorbed by humans. Mushroom stalks can contain small amounts of B12 if the fungi have been grown in a medium that includes animal manure. However, the quantity is too small to prevent a deficiency of this vital vitamin.
In most people over the age of 85, the ability to absorb vitamin B12 decreases. For those people, a supplement makes good sense. ☼