Diets are like cars; we all deal with them, and up to a certain point the more you know the more you'll get out of them. That certain point is actually a pretty low threshold of knowledge in either case - but you wouldn't know it from the vast literature and ongoing conversations on tinkering with cars or tinkering with diet. A few recent and lengthy posts at Chronosphere serve as an example of the tip of the iceberg:
- Interventive Gerontology 1.0.02: First, Try to Make it to the Mean: Diet as a life extending tool, Part 1
- Interventive Gerontology 1.0.02: First, Try to Make it to the Mean: Diet as a life extending tool, Part 2
- Interventive Gerontology 1.0.02: First, Try to Make it to the Mean: Diet as a life extending tool, Part 3
There's enough reading material beyond those links to keep you occupied for a while, and it's the merest drop in the ocean of basically sensible discussion on optimizing diet, which in turn is the merest drop in the ocean of published nonsense and idiocy when it comes to what we eat. At this point in my years of looking into life extension, and despite a general lack of interest in the finer points of nutrition, I could probably run up a lengthy essay or two of my own - but the final paragraph would be "and ignore all of what came before: just practice calorie restriction as laid out in any of the Calorie Restriction Society-recommended books on the subject, exercise as recommended by your physician, and take a good multivitamin."
Optimizing your diet is like optimizing the engine in your car for long-term use. How much time and money do you want to spend on this as a project? However large your answer, you can easily find ways to spend those resources - it's a deep rabbit hole, with many side-passages, and one that lacks firm measures of success. Unless you make it your hobby and are happy tinkering for the sake of tinkering, I'd suggest that it's largely not worth it. You'd be better off doing something with your time that is more likely to prove constructive in the end.
Look at it this way: the research community has established that no dietary practice is better for health and longevity in a range of species than calorie restriction - coupled with any of the standard, sane, recommended balanced diets of the sort that have been well known and well publicized for decades. The results in humans are eye-opening when it comes to measures of health - if calorie restriction was a drug, pharmaceutical companies would be advertising it on every billboard and it would be a household name. Do you think you can do better than the decades of work put in by the entire scientific community? You can't. If you're investigating odds and ends of interesting publications and theories on diet around the edges of the field, then by all means have fun if that's the way you like to spend your spare time. But don't think that you're getting ahead of the game - that's not the way the world works.
The bottom line is that if you want to optimize your diet, just sensibly practice calorie restriction. End of story.