This is going to be the shortest piece of advice you will ever read on nutrition:
Find out what works for you and stick to it. The end.
Okay, a little explanation: I have found talking about nutrition to be more controversial than religion, so I am not giving any advice on it other than my one nutrition rule above. Whether you are vegan, paleo, carb-loading, carb-loving, carb-hating, plant loving, juicing or protein shakes, I really do not care. What I do care about is that you are paying attention to your nutrition as one of the three critical components of boosting and maintaining your energy, the other two being sleep and exercise. I’ll never forget what I heard at a CrossFit seminar on nutrition the 1:23 rule: it doesn’t matter if you exercise diligently for an hour every day, if you don’t pay attention to what you eat in the other 23 hours, you are wasting your time.
Microsoft used to offer an incredible free benefit to its employees: Free nutrition coaching and guidance with their free local gym. You would see employees transformed over a period of several months as they changed what they ate. The plan was irrelevant; the priceless part was the accountability. The program that had a $4,000 value was free if you hit your target goals. That level of commitment meant nobody signed up unless they genuinely believed they could stick with it and hit their goals.
If you need to change what you eat, consider how you can be held accountable to change and stick with it.
To your continued success,