I've been really impressed by Dr. Terry Wahls, who developed multiple sclerosis, tried all the usual medical treatments, got some small improvement with nutritional supplements and then got amazing results when she fed herself a super nutritionally dense diet. She figured that whole foods likely contains thousands of useful compounds that are not yet identified and included in nutritional supplements, and I think she is right.
Through years of personal study, Dr. Wahls identified 31 microntutrients that the mitochondria need to function. She then learned what foods provide those nutrients and came up with her "9 Cups Daily" protocol: 3 cups (about one heaping plateful) of leafy green vegetables, such as kale, collards, chard, spinach or lettuce, which provide vitamins A, B, C and K. 3 cups of sulfur-rich vegetables, such as cabbage, broccoli, cauliflower, onions, garlic, mushrooms and asparagus, because they support the removal of toxins from the body. 3 cups of colorful vegetables and fruits (ideally three different colors each day), because they're full of antioxidants. They have to be colored all the way through, so apples and bananas don’t count as colored, but berries, peaches, citrus, beets and carrots do.