most of life... naturally"
Our word “diet” comes from the Greek word “diaita”, which means “way of life”. To be sure, the foods we eat day in and day out are a major determining factor in our quality and way of life. Changing a person’s diet may be one of the most invasive therapies available to any practitioner and it should not be undertaken lightly. When you change your diet you change not only the foods you eat, but where you can eat, where you can go, who you can socialise with, and most people with think you at least a little bit crazy if you tell them you can’t eat this or you must eat that. Indeed, changing your diet means a huge change in your way of life.
Theories about ideal diets abound – at times there seems to be more theories about diets than foods on the planet. Facts and the truth are often obscured by baseless theories about diet. As a species, humans have demonstrated an astounding ability to adapt to nearly every environment on earth... from the tropics to the arctic, from the desert to rain soaked islands (like this one). Before modern agriculture, transportation, preserving, and refrigeration each of these regions and climates produced their own unique stable food supply, each one significantly if not completely different from the foods of other regions. The remarkable thing is that we humans survived in every one of these diverse environments, so the idea that some of these foods are good for us and that others are bad for us should be suspect at the very least.
Indeed, such biodiversity and adaptability calls into question dubious pseudo-ethical arguments about the types of food we “should” eat and “should not” eat. Arguments in favour of vegetarianism, for instance, run into trouble with the simple realization that the human brain could never have evolved without fish as a steady and substantial part of our ancestral diet. Similarly, arguments for a carnivorous “caveman” diet hit problems when we realise that not a single fruit, vegetable, nut or domestic land animal that we consume today existed 10,000 years ago – they have each been bred and hybridised into their present form by human ingenuity (not to mention that for the “caveman” diet to be authentic, you would also have to run at least 40km a day and live without central heating or air conditioning).
We can glean two very important principles from these observations. First, there is no such thing as an ideal diet for humans. All we can hope to do is clarify general dietary guidelines that will guide us to better health. Second, one of the most amazing things about us humans as a species is that we can eat almost anything and survive. Only the pig comes close to us in this ability to thrive by eating any type of food. (Interestingly, the pig is probably the second smartest land animal and both biochemically and physiologically is extremely close to humans – This similarity between pig flesh and human flesh may help explain why humans go into a mild state of shock every time they eat pork).
On the one hand, we are blessed like no other generation before us in terms of the abundance and varieties of food available to us. Thousands of years of plant selection and animal breeding have given us vegetables, fruits and animal products unimaginable to our ancestors. Worldwide distribution and refrigeration afford us the luxury of fresh strawberries in February and preserved foods that can remain edible for decades, making famine, at least in the developed world, little more than a distant nightmare. Few of us have known hunger, let alone starvation. Yet, the irony of this phenomenal success is that most of us will die from over-eating. 70% of all deaths are linked to some degree to simply eating too much. Heart disease, hypertension, diabetes, stroke, senility, and many types of cancer have overeating as a major contributing factor.