Nutrition is a wide topic for general discussion from which we can take various scientific facts to explore this field, but where especially personal experience and testament always plays a central figure, since we all do eat, right? In essence our biology is certainly designed to eat a certain way, but we are also highly individual. Sex, age, body type, which already creates unique genetic factors, the climate and natural environment one lives in, level of physical activity, other subtleties yet undiscovered, all these set the conditions which can make the difference between my and your ideal dietary choice. So in that respect I think that not only is everyone directly responsible for their health and longevity, which should be obvious, but also it's everyone's job to explore what is right for them, and actually undergo the personal journey of trial and error which will ultimately lead one to discover the language of one's own DNA, to know what makes you feel vibrant and true to God healthy, rather than what just merely sustains you..
This is IMO the mistake of standardizing diet, take the standard American diet for instance, or the typical food pyramid which we've all seen on the side of cereal boxes and public school classrooms, which is really just a sustenance model, not a guide for a healthy lifestyle. There is no one hat for every head, just like there is no one person who is just like you. So even while taking in all the health science out there, I would still continue to value what my body tells me more so than the scriptures, as long as they don't clearly conflict with another. My personal journey to leading a healthy lifestyle has been one of shaky commitment for a very long time. I used to read a lot and only occasionally put my findings into action. I would let myself become too influenced by habit and the habits of culture, which really only lead me down a mediocre road. Something recently switched on within me, as most times in life, unexpectedly.
Today I eat nearly 80% raw and unprocessed fruits, greens, and vegetables and the way it's going right now I aim to increase it up to 90% by the end of the summer. I cannot cease to repeat how much greens and especially the blue-green microalgae spirulina have increased my energy levels while at the same time decreasing my caloric intake. This has also caused me to begin to question the century old model of calorie requirements for the human body, but I do not wish to jump to any conclusion at this point, only that I feel that a new paradigm of nutrient density lies somewhere unwritten in the works..
A couple of tips just to share, take what fits your shoe 
- Drink out of a huge freaking glass. Yes, size it up. I drink my water, tea, and smoothies out of a 1 liter mug. Water is so so vital, sometimes I still try and wrap my head around this fact. People today just simply do not drink enough liquids. Increase the size of your glass, and you increase the amount of water you have available to drink. Just do not drink this much right before or after a meal. Give it an hour space. Nobody benefits from diluted digestive juices. Drink immediately in the morning as you are most dehydrated at this time of the day. I manage to check this by drinking my breakfast.
- Make meat a kind of luxury. This may prove difficult for some who view meat as a cornerstone of their diet, but there's plenty of evidence out there showing that the human being is not biologically built to be carnivorous, he just plain isn't. This doesn't mean that meat will not sustain, but it's too easy to become excessive with it, and that's when meat becomes a really big health issue. A large population of the technological civilizations suffers greatly from this, disease statistics alone show this. Try to consume meat in small servings when it is available, but do not actively seek it out. So at family dinners, social events, things like that. On anybody's road to the best attainable health possible, cutting meat out of one's diet will always be a very significant turning point!
- Inspire yourself! Make a calendar. Create a piece of art that is your eating style. Align yourself with a mission, and set out in small steps. Big breakthroughs will come, but probably only spontaneously so out of your control. Long term gains will reveal themselves based on all the small steps you took to get to where you are!
That's all I got for now. My body's telling me it would love a banana. I think so too. 
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