Some people choose a plant-based diet for health reasons, while others do so with more ethical concerns in mind. On the other side of the dinner plate, some meat lovers put little thought into whether they should or shouldn't eat meat, while others will defend their right to chow down on animal muscles until the end of time.

Passions can run surprisingly high when it comes to dietary decisions. Food is a matter of survival, and deep down in our primate brain, we still feel that we need to defend our food sources.

Today, we are not concerned with the ethics of the meat industry; it's not that they aren't important, but that we are more focused in the biology involved. Similarly, we tend not to dabble in the debate surrounding the environmental impact of meat rearing; we will leave that for others to chew over.

This article will be served in two courses. First, we ask whether or not humans are "designed" to eat meat — did we evolve to consume it? Then, we will ask which option is best for our health.


So, are we carnivores?
This is the first question to answer, and, anatomically, it seems to be a simple one. We don't look like carnivores; our teeth are no good for ripping flesh, and our guts are too long. Are we herbivores, then? No; our guts aren't long enough, and our teeth don't quite fit the bill.

We are, it seems, omnivores; our bodies can handle both meat and plant matter pretty well. It's not quite that simple, though. Just looking at an animal's teeth and gut is no surefire way to distinguish its diet. The panda — with killer canines and a bamboo diet — is an excellent example.

That being said, it is true that most creatures have a gut suited to the diet that they consume. Lions, for instance, have huge, smooth-walled stomachs for holding hunks of animal. Many herbivores, meanwhile, have massive, plant-destroying factories in their abdomens, where bacteria smash apart the tough constituents of plant matter.

We humans like to think of ourselves as special, and, in many ways, you could argue that we are. But when it comes to our internal tubing, we are monumentally average.

Rather boringly, the human gut is very similar to that of our closest relatives: monkeys and apes. It follows that, if we are looking to work in harmony with our guts' design, our diet should be at least similar to our cousins'.

When we examine the diet of virtually all monkeys and apes, it's nuts, fruits, leaves, insects, and the occasional snack of flesh. You may have seen rather shocking footage of adult chimpanzees killing and eating baby ones, but that's a relative rarity compared with the quantities of non-meat products consumed.

From these observations, we can perhaps conclude that evolutionarily speaking, we shouldn't necessarily be vegetarian and evolved to eat only the occasional tidbit of animal matter.