If you are eating the right diet, it is not stressful any more than proper training is "stressful". A bit of discipline is needed, just like you wouldn't do just random workouts with no guiding principles to fulfill your running potential. If you want to realize your health potential, your diet should be free of cravings and impulses, should provide consistent energy all day, it should leave you free from pain, injuries and inflammation, and make it effortless to maintain lean muscle mass, i.e less than 10% bodyfat for men. When the shirts come off in the summer it is easy to tell who has theses things figured out.
Just like with training methods, study what others are doing, try it yourself, and see if it works or not. And as with training, rather than being stuck in dogma ("x" miles/week, hit every split, etc), allow your diet to evolve based on your body's feedback. You may be very pleasantly surprised where you end up in a few years.
One thing is for sure, if you get all of your information from mainstream media, you will get the results that every one else is getting. Which, in my country anyway, is of a very low standard and personally unacceptable. Just take a look at pictures of random people in the U.S. from the 40s, 50s and '60s, compared to teh general public today. Something very wrong happened with food and diet in the '70s and the result is the Tsunami of obesity and health dysfunction we see today.
The mind and body as a system is very complex and dynamic, especially in the context of aging and performance. Nature doesn't care about your beliefs or good intentions. It's either evolve or die out. On the other hand, when it all comes together, the simplicity, freedom, power and ease is almost overwhelming to behold. You have become that rarest breed: the happy, healthy human animal.