We don’t often give a lot of thought to why some things taste good and others don’t. Why do almost all humans enjoy things that are sweet, salty or savory?
Charles Darwin has the answer to that question, and it’s the same reason behind the obesity epidemic that America and other nations are facing.
Imagine living as an early human, a hundred thousand years ago. Food, while not scarce, wasn’t easy to come by. We didn’t farm grains or raise livestock, so anything we ate had to be killed or found first.
When faced with new terrain, animals and plants, it’s natural to assume that the people who were best at telling the difference between nutritious foods and poison were the ones who would live to reproduce.
It’s because of this evolutionary imperative that we now find certain taste sensations, like those we get when eating salty, savory or sweet foods, enjoyable.
Why we like salty and savory things
Salt is the prime example of an evolutionary need that is over-satisfied by today’s diet. In hunter-gatherer times it was necessary to develop a separate sensation for saltiness, because salt was difficult to come by and we need trace amounts of it in our diets. However, salt is no longer scarce, so we often over-indulge in something that our bodies tell us we want.
Salt is linked to many cases of obesity and rapid weight gain – one of the fastest ways to lose weight is to cut salt from your diet.
The taste we call ‘savory-ness’ developed because early humans needed to be able to tell which foods were good sources of protein. Protein was scarce, because early humans didn’t have regular access to meat.
The sweet taste of obesity
Sugar has a similar back story. We all need sugar to survive, as it is one of the most readily available forms of energy. Simple and complex starches are always broken down into basic sugars, but digesting these things into usable energy is more difficult than just eating a spoon of sugar.
In nature, without refining natural sugar, the only way to get any simple sugars in your diet is to eat sweet fruits and vegetables. This is why we developed a taste for sweet things. Sugar wasn’t very plentiful, and since we led much more active lifestyles in general, being overweight was extremely uncommon, and normally only occurred as a result of a hormone imbalance.
Unfortunately, it’s no longer very difficult to get sugar in our diets. Almost all processed foods contain some kind of sugar – even lunchmeats and things where you wouldn’t expect it. Our ability to manufacture food has increased dramatically, but our digestive systems are largely unchanged.
The amounts of sugar we take in on a daily basis represent a complete energy overload. That’s why a lot of dieticians are recommending diets like the Paleo Diet, which emphasize lean meats, vegetable proteins and complex carbohydrates.