If you’ve read anything I’ve said, it’s based on Paul Jaminet’s calculations of the body’s need for glucose. He estimates 600 total calories from carbohydrate and protein, with at least 200 calories coming from each, will meet glucose needs and preserve lean mass. You’d need to add roughly 100 calories per hour of moderate exercise. Total calories will depend on weight, metabolic rate, activity level etc.
An example might be 5 eggs, 600ml of kefir, 100g of oat bran, 200g of Greek yoghurt, some onion and turnip for roughly 75g, or 300 calories, each of protein and digestible carbohydrate. Non-starchy vegetables aren’t reliable for carbs because they’re largely bacteria fodder. In this scenario, you’d need to get 1400 calories, or whatever allows you to get what you require, from fat, but you could up either of the other macros to a ratio that suits you.
The effect of diet on brain chemistry is incredibly complicated and individualised. I only recently learnt that amino acids can affect it, so getting all your protein from one source may not agree with you. Glycine, found in large amounts in gelatine, may help, and can be purchased in an easily dissolvable form, e.g. Great Lakes.
Meeting the 200 calorie carb target will also keep you out of ketosis, which reduces your body’s need for cortisol (a stress hormone). It also makes life easier for your thyroid, which should lower anxiety and increase energy, appetite, libido etc. Keeping your thyroid in top shape is actually incredibly helpful in recovering. If you suspect any weaknesses, get it checked out.