by Tyler J. Arsenault B.A.Sc (Nutrition)

I love nutritional science; how those little molecules from other things that we jam into our mouths eventually become pieces of ourselves. We literally are what we eat – that’s a fun notion that has kept me passionate about nutrition for nearly 20 years. Outside of the applied science however, I also love discussing nutritional philosophy; it rarely grants us truth or answers with respect to nutrition and the way we should eat for maximal health, but it’s an exciting and thought stimulating process.

Among my favourite nutritional musings is the notion of “what we are meant to eat”. Not a week goes by where I don’t discuss what humans are “meant” to eat. Examples such as:

“Humans weren’t meant to drink milk. We’re the only species to drink the milk of another animal”

“Humans weren’t meant to eat meat for (insert reason here)”

“Human were meant to eat a paleo diet. Basically, we should have stopped eating differently after the Paleolithic era – that makes total sense.”

Let’s ponder the word “meant” for a second. What does the word “meant” imply? First, it implies that there is a plan for how we should eat; it implies that we were designed a specific way. “Meant” implies that we have a fate, a purpose, a destiny – attributes that frankly can only be associated with the position that we were created by a divine being with a purpose. Now, I’m not going to get into a theological argument for two reasons. First, because you can’t discuss God(s) in a blog post, and second, because God has no actual place in a discussion regarding the applied science of nutrition. God is unfalsifiable and no living being can claim to know the mind of God with respect to how we should eat. Only if this were true could we truly say “we were meant to eat a certain way”.

When someone says “we weren’t meant to eat that”, they are committing a logical fallacy – the “appeal to nature” specifically. Just because something appears to be unnatural, doesn’t mean that it’s wrong for us to do. Riding in an elevator appears unnatural, texting our friends by harnessing the powers of electrons and wavelengths appears unnatural, and eating fruit in the middle of winter living at 45 degrees of northern latitude appears unnatural. But the mere fact that we do these things without breaking the laws of physics makes them perfectly natural. Raising the dead with necromancy?  Unnatural.  

Inedible by Geoff Stearns licensed under CC BY 2.0

Let’dive (briefly) into a few common examples:

Statement: We’re the only species to drink the milk of another animal. We’re not “meant” to drink it.

Reply: We’re the only species that wears shoes when we leave the house, but if you place a plate of milk down for your dog or cat, watch what it does. Many animals will drink milk given the opportunity; in fact predators often do when they kill a lactating female. Humans drink milk because we have the capacity to do so and a dog will drink a plate of milk because their human counterparts have the capacity to do so. Are there discussions to be had about the consumption of milk? Yes. Is milk for everyone? Absolutely not. Is drinking milk natural? It so happens that millions of people do it – therefore in a strictly scientific perspective it most certainly is natural.

Statement: Flies won’t even eat margarine. It’s not even real food and we’re not “meant” to eat it.

Reply: First of all, there are a lot of things that flies won’t eat. Raisins, cashews, tea, table sugar (long list), and my dog doesn’t eat cucumbers for some reason. Does that mean that those foods are also unfit for human consumption? Not all margarines are equal and some are certainly far worse than others, (and it’s most certainly not “almost plastic”), but humans have found a way to recombine fatty acids on a glycerol backbone to make liquid oils solid at room temperature. It’s true that margarine isn’t naturally occurring – but neither is the vitamin B12 that’s in your almond milk. Choosing to categorize foods as either healthy or unhealthy based upon the likelihood of another entirely arbitrary species eating it? Come on.

Statement: Humans were meant to eat the Paleolithic diet. I mean, that’s what humans ate originally right? We weren’t meant to harvest grain and turn it into bread!

Reply: Why would /should eat the same way humans ate over 10,000 years ago? So we can die of starvation and malnutrition like they did? Don’t get me wrong, I’m a big proponent of many of the recommendations of the paleo diet – the strict adherence to whole foods and avoidance of refined sugar being the bigger ones – but they are consistent with mainstream advice so it should come as no surprise.

Modern nutritional science has been based on nutritional need; identifying vitamins, minerals, phytonutrients and macronutrients that cause a person to not just scarcely survive (as they did in the Paleolithic age), but rather thrive. The Paleo diet makes some good recommendations, but the rationale for eating it is just not something widely accepted by the vast majority of nutritionists including myself.

So you see, “we were meant” is something that no human could possibly know. It places limits and barriers in our lives without any good reason for doing so. There are things that are good for our health, and things that are bad for our health, and not in any absolute sense. Take care not to confuse nutritional science with nutritional philosophy, as only the former can be discussed with any level of fact while the latter makes for some interesting and exciting conversation but should never be taken too seriously.

If you have a nutritional topic you’d like to discuss, feel free to leave it in the comments below!