Humans are not herbivores. Technically we are omnivores, but for the most part we are by design carnivores. Our proper diet is animal-based, high fat, medium protein, and low carb. This is the ancestral diet.
Our ancestors lived longer than we think. The lifespan was statistically less because of infant mortality, lack of antibiotics and dental care, and warfare. Otherwise many more lived beyond 100 than today, and they had little to no of what we call chronic disease. They were lean, muscular, high energy, mentally clear and focused. They had to be to survive and thrive. Or we wouldn’t be here.
We call this today the keto/carnivore diet. But it is the ancestral diet. The ancestral food pyramid is basically the false, inverted USDA food pyramid re-inverted in the proper order. At the bottom is fatty cuts of red meat; rib eyes, chuck roast, high fat hamburger meat, any beef, lamb, bison, chicken wings, chicken thighs, and chicken legs, pork ribs, pork belly, bacon.
The next level up is wild caught salmon, sardines, mackerel, shrimp, mussels, oysters, crab, and lobster. The next level up are eggs, especially farm fresh, organic, pasture raised. The next level up are occasional small amounts of organ meats: liver, bone marrow, heart, kidney, and sweet breads.
The next level up is a little dairy: especially grass fed butter, yogurt, keifer, and hard, high fat cheese like cheddar. The next level up are very modest amounts of low carb fermented veggies: saurkraut, kimchi, pickled artichokes/asparagus/cucumbers. The next level up are very, very modest amounts of non-fermented veggies: cruciferous vegetables, and leafy greens.
Towards the top is a small category for fruit: avocados and a few berries (blackberry, raspberry, and strawberry). At the very top is a daily piece of high percentage cocoa dark chocolate.
If you follow this way of eating, and are dealing with serious chronic illnesses, this will radically improve your health.