Your mind, body, and DNA are all adapted to survive in an ancient world; in which a stone knife was best-avail-tech and obtaining enough food was a constant struggle. Today’s humans have brains and bodies very similar to ancient human Cro-Magnon ancestors, yet human cultures and technologies can change much much faster than human DNA sequences (ignoring ionizing radiation…for now). Sometimes, the human mind/body does not fit perfectly into the new technological clothes that humans seek to wear, no matter how superior. Here’s a few examples.
Human ancestors were primarily hunter-gatherers, with emphasis on the gathering. Most places had animals to hunt and eat, and humans did just that every chance they got. However, animals can be eaten much faster than they reproduce. Perhaps the best hunters had large families that turned into clans that turned into tribes, but at some point, the animals got scarce and roots, shoots, and fruits became what’s for dinner. Humans rarely got to eat as much meat as they wanted–then. Nowadays, a significant minority of humans could eat a couple pounds of bacon for dinner. All human cultures disseminate much food knowledge, and it is rare that humans will eat bacon by the pound no matter how good it tastes. They unually know a little about heart attacks, and saturated fat, and also steaks. Even so, there are many many people who are fat and sick, because they have unreliable hard-wired instincts regarding tasty and plentiful fatty acids.
Some of these fortunate humans now have access to new foods, some of which never existed previously. There are wonderful new breeds of plants and animals; plus food production, prep and storage have improved, but modern technologies also make it possible to turn starch and chemicals into a hyperpalatable Day-Glow Snak Fud. Alternatively, food chemists can turn corn starch into corn syrup while keeping a particular ratio of fructose-to-other-sugars that happens to taste very good, and they can do it to millions of tons of starch if the engineers and moneymen are willing. Other creations of theirs can be stored nearly indefinitely, or exhibit more vibrant colors than printer’s ink, or even make truckloads of soft white bread using only the endosperm from billions of wheat seeds plus yeast and chems. (A trick worthy of any magician, even tho the end product is often called white bread. How they do it while managing to sell it so cheaply is also marvel-worthy. Too bad it was not a common stone-age food.)
There’s always more to any good story. Your ancestors never had to deal with radionucleotides or bio-accumulators like DDD, a no-longer-used insecticide example thereof. Rachel Carson summarized one bit of DDD research in her 1962 book ‘Silent Spring.’
“Plankton organisms were found to contain about 5.3 parts per million of the insecticide (about 25 times the maximum concentration ever reached in the water itself); plant eating fishes had built up accumulations ranging from 40 to 300 parts per million; carnivorous species had stored the most of all. One, a brown bullhead, had the astounding concentrations of 2500 parts per million. It was a house-that-Jack-built sequence, in which the large carnivores had eaten the smaller carnivores, that had eaten the herbivores, that had eaten the plankton, that had absorbed the poison out of the water.”
*Carnivorous species had stored the most of all.* The world that has gotten much dirtier since 1962. To test an implied prediction, I’d expect to see modern meat-eaters with rising cancer rates, falling reproduction rates and/or increases in birth defects, and other medical problems. I’d expect people to test positive for chemicals that bio-accumulate. I’d expect to see other animals that eat high on the food chain exhibiting some of these problems. The science is out there; Rachel Carson reported the truth.
There are more reasons for humans to eat low on the food chain. The calories in the corn presently fed to cows far exceeds the calories present in the cow’s body, and there are seven billion humans on this planet. Cows and pigs (and to a lesser extent chickens and fish) are an inefficient use of human foodstuffs merely to activate taste buds and brain cells. Feeding inedible grasses to cows, an efficient way to obtain human calories, is now more difficult. Some radioactive by-products of certain nuclear misadventures bioaccumulate at various rates, and internal ionizing radiation exposure is vastly more harmful than external radiation exposure (like X-rays). Radioactive grass can become even more radioactive steaks.
Hope this helps my fellow SpaceShip Earth passengers maintain their good health!