The way I see it, we can use food (nutrition) for 1 of 3 things:
1. To get fat, get diseases and generally promote ill-health by eating the wrong stuff (usually from being uninformed), addicted to food in one way or another, or by seeking food for pleasure only.
2. As medicine to get health* by repleting adrenals, recovering the gut, and generally giving the body what it needs to heal itself… because it will.
3. As a drug to get lean/muscular/perform better by timing elements to manipulate hormones to get desired effects on performance and/or body composition.
Obviously there is a lot of overlap here. Things aren’t clear cut… but there are general concepts for each that must be understood.
The general recipe to get fat and unhealthy:
Eat predominantly refined carbohydrates and processed foods and drinks with lots of chemicals and preservatives. Eat sweeteners everyday and avoid anything natural. Don’t exercise, sleep badly, drink lots of alcohol, and stress out about life/work/finances/relationships all the time. Worry as much as you can and be sure to keep your energy levels high with lots of stimulants. Look negatively at everything and make sure doubt is always present in your mind. Get angry with people around you and have general resentment for life. Oh, and throw in some really hard exercise that you are not ready for.
This lifestyle will lead to adrenal fatigue and insulin resistance very quickly… this will make you unhappy, fat and diseased. How many people do you know that live elements of this extreme example?
General recipe for health:
Have a greater focus on nutrient density. Think: a diet of rotated organic whole/natural state foods (rotation is for intolerances) with journaling, vit/min, fish oil, fermented foods, high quality fresh vegetable juices, raw dairy, and high quality meats for starters. Low level exercise at first, walking, meditation, food awareness work especially if you are very overweight… develop a relaxation ritual that you do whenever you feel stressed. Get your guts in line with probiotics and hcl/digestive enzyme supplementation if you need it. Work on intuitive eating and sensing what the body needs. Work to get at least 8 hours of high quality sleep every night and sleep before 10pm. Gradually incorporate a well rounded training protocol based on your goals and predisposition. Play recreational sports. Enjoy life, laugh a lot and generally have fun with friends often.
General recipe for leanness/performance: 
First and foremost you MUST workout. Then you MUST have health or have a good framework of understanding so you can make informed decisions. Once you have these things in place you can use timing and specific nutritional tactics to mimic drugs… almost like taking steroids if done right. Basically using food as a fuel only and removing feelings about ‘what you like’ or ‘want’ to do. Literally using food as you would drug doseages… like a scientist. It is not necessarily healthy long term.
Again, there are ways you can mix these and have high health and performance together, but I want to draw clear distinctions.
Health and understanding is first. Those who are unhealthy and uninformed who try to manipulate timing, use tactics, or do other ‘diets’ will usually fail due to a poor foundation physically, mentally and/or emotionally. You HAVE to build a groundwork because there are no shortcuts. You, reading this, do at least one thing really well. Maybe better than anyone you know… and to get that skill you had to work hard right? If someone asked you “hey, how can I achieve what you achieved in 10 years, in a few months?” You would probably say… “umm, sorry, you can’t dude”
So understand that, like with everything, these things take time. One step, one more day of learning new things and gaining more experience.
* By health I mean (among other things) someone who is happy, laughs a lot, loves the people around them, sleeps well, digests and poops well. Is horny and has high energy through the day and is sleepy at night. Someone who can do any normal physical task (carry grocery bags or take a hike for 3 hours on a saturday without being accommodated for) and doesn’t worry about things all the time. Cool?