We are what we eat, true or false?

“Tell me what you eat, I’ll tell you what you are”, this sentence is atrociously poetic, isn’t it?

But even Jean Anthelme Brillat-Savarin, the French lawyer we cite, had no idea years ago of the snowball effect this phrase would have in the scientific community.

Will I become an apple because I ate one this morning? Hmm, not sure it works like that

Why then, and for decades, has this phrase been used around the world to promote a healthy and balanced diet? Every day, a human being replaces 330 billion cells in their human body. The replacement of these cells is fueled by the food we eat. Indeed, it is our diet which provides the energy necessary for the production of these new cells (through many physiological mechanisms).

It therefore makes sense to say that what we consume gradually becomes part of us, literally.

Do you realize how eating a piece of fudgy brownie, or drinking hot chocolate after a hard day at work helps you feel better instantly? The science behind the "sugar rush" is simple: after eating foods high in sugar, the brain produces spikes of dopamine. The latter plays a role in the feeling of pleasure and contributes to a feeling of “euphoria”. This is why the brain begins to consider foods high in sugar (or more precisely foods with high palatability = foods providing maximum energy for minimum effort) as a reward.

A serious study on the relationship between spicy foods and an aggressive temperament showed more aggressive reactions on people who consumed spicy foods compared to others who did not consume spices.

High-protein diets showed individuals with higher motivation and higher feelings of satiety (no longer feeling hungry more quickly).

Aside from the neurological control that diet has, a remarkable study conducted by the Department of Plant Science at the University of Oxford has indicated that our diet affects our genetic makeup. Indeed, the extent of changes in dietary nitrogen showed how genome evolution can be influenced by adaptation to different diets and environments . Our diet therefore has an impact on our genetic makeup!

We can also ask ourselves: how does food impact the way we age, and how it triggers physical changes in our body. So, if we dig a little deeper, a recent study showed that the Ybx1 gene, a major transcription factor regulating cellular homeostasis and the maintenance of our stem cell population, was down-regulated during aging. On the other hand, it is upregulated after caloric restriction, which would therefore play a role in the prevention of aging at a cellular level.

Finally, a second study, to analyze the effects of “junk food”, was carried out on young male children aged 12 for 5 days. This led to a reduction in the ability of their muscles to transform glucose into energy, and the development of insulin resistance, which is correlated with an increased risk of type 2 diabetes.

After reviewing these different studies, we can understand that our food choices do not only impact our external appearance, but also the way our brain acts and the functioning of our body.

So if we are what we eat, what would you be?