Rather than “fruits, vegetables, and nuts” being healthy, consider it from an evolutionary standpoint: go into the wild today. Pick some random plant. Eat a bunch of it. What’s the chance you would get extremely sick? Plants want to live and protect their offspring and do so by creating tons of toxic compounds.
Take a modern staple crop: Potato. Potato wants to live and thus produces glycoalkaloids alpha-solanine and alpha-chaconine, which can reduced by peeling the skins off. They are concentrated in the sprouts and flowers because these are the reproductive parts of the potato.
Mashed potatoes should be boiled once before use and the water discarded. If you taste the foam that comes out from boiling them, it tastes quite bitter. Green potatoes exist because when potatoes are about to sprout, protecting the new growth with chemicals is the highest priority to ensure its survival.
Cassava wants to live and thus produces linamarin, a cyanide containing compound. It should be noted that growing stress increases the toxicity of plants.
Some traditional cultures are aware of this characteristic of plants and soak/peel their almonds. Other cultures peel and deseed their cucumbers.
Methods for dealing with plant toxicity
These are some common methods that cultures use on plants to make them less toxic. Sometimes, a combination of these are used. Some toxins may not be removable with these methods.
- Peeling
- Deseeding
- Washing
- Soaking and discarding water
- Parboiling and discarding water
- Fermenting
- Sun bleaching
- Soaking then peeling
- Sprouting
- Pressure cooking
- Grinding into flour
- Selective breeding
- Eating a specific part of the plant
- Not stressing the plants when growing or handling them
Advice for the modern age
As a general principle, avoid things that are bitter. This database of bitter foods includes caffeine, quinine (tonic water), and so on. Quinine was implicated in causing deafness in pregnant women in the first half of the 1900s. Stores sell bitter things such as cacao water and lettuce in sandwiches often tastes bitter. Yes, humans can get past their natural feelings, but I don’t advise it. In my framework, the some of the worst foods tend to be seeds: beans, lentils, pulses, and nuts.
Though a lot of drugs are chemically synthesized, it makes sense that a lot of things such as tobacco, opium, paciltaxel,