this is my personal take on dieting, and the basis for any dietary knowledge i give to those that ask me:
your body has been around for a few million years really. the "source code" for how it uses molecules found outside itself, converts them into energy and nutrients, and all the physiology involved therein, has been around - think very deeply on this thought - for millions of years. modern human bodies have been around for around half a million years. thats a very long time.
i believe the last mass extinction event to really threaten homo sapiens was 65,000 years ago (almost all of our genetic diversity was wiped out in this massive climate change, resulting in the gene pool we have around today). so weve got a backstory millions of years old, and all of us today can draw a connection to the few hundred (to potentially tens) thousand humans that survived to procreate. sidenote: cooking is also around this time period (although some argue ~2mil).
agriculture is around 12,000 years old, and having become globally prolific around 9,000 years ago. reminder - this is when grains effectively entered the diet. animal domestication is only around 7000 years old, and even with that, it may really be about 4-5,000 years ago until it was on a scale we could compare to times of recorded history. civilization is only about 6000 years old, and history starts to effectively enter the scene around 4000 years ago, but real recorded and well documented history is only around 2500-2800 years old.
in the last 50 years, food and food availability has seen an absurd and shocking change. now i started this timeline millions of years ago. 50 years is not a long time. 50 years is one fraction of a blink of an eye in the history of our genetic source code, our digestive systems, and how we make use of food for energy and nutrition.
our bodies are in no way shape or form adapted to the means with which we currently consume food in the West (and well, the world).
so with this, i make the claim that veganism is entirely dependent on modern culture. youd die very quickly in the world our bodies are adapted to, highly unlikely you would survive long enough to procreate. is it "healthy?" certainly more healthy than eating red meat and cheese every day of your life. however, the human body is not adapted to it. i wouldnt recommenced any person on earth become a vegan.
vegetarianism is not plausible in a time without civilization, although possible. our bodies are not well adapted to the absence of meat, but provided that we have access to all the proteins we need, and get plenty of them, there isnt much of a problem. however, grocery stores and restaurants are rather alien to this world, and without modernized societies, you take what you can get. you are entirely dependent on agriculture to survive.
eating meat and animal products: how easy do you think meat was to come by in this prehistoric world our bodies are finely adapted to? meat is a luxury. its packed with vitamins, wonderful source of proteins and heavy minerals, magnanimous in fat, its like an ancient world multivitamin. not something youre going to see every day either. in fact, our bodies are wonderfully adapted to consuming meat in very small doses only a day or two our of what we now call a week. not only this, but the amount of energy required to obtain meat was immense. not only do you have to catch up with and fight your meat to the bloody death, you had to be damn sure you diddnt fuck yourself up in any way in the process. then, much energy is required just getting to the meat. then there is the aspect of bringing it back home and cooking it (cooking and adapting to cooking has had wonderful advantages, something that may have given us a great advantage over other hominids who lived on earth around 50,000 years ago).
eating meat every day has terrible, and insidious, consequences. even if you feel healthy, and look healthy, your body is in no way adapted to eating meat every day, and with other animal products, they should be kept to a minimum in a day (but hey, having a bit of yogurt every day is pretty kickass). eating meat several times a day is wasteful and gluttonous. the amount of calories, fats, and nutrients in meat is very high (lets hope were all eating organic, free range, all natural diet fed animals

). eating excess amounts of steak, for example, is doing nothing productive and giving your body way to much stuff to process that it simply is not adapted to do. the result is all the nasty side effects of eating
too much meat we see in the USA and elsewhere today. keep it real - keep it ancient world real - meat is a luxury to be enjoyed once or twice a week. the environmental benefits of eating this little meat would be astounding as well.
junk food: it shouldnt exist. there is where i stand on that.
view molecules as data, and your body as a computer. its adapted to taking in a certain profile of data every day, and skewing that profile heavier in some directions and lighter in the others will fuck up the computer in enough time.
my core spiritual beliefs include a longing for the return to our nomadic, harmonious, and balanced existence with this universe (planet, whatever scale you wish). that being said, i am fond of envisioning an existence free of the dependencies on the world weve created. in any event, think about the scale between how modern society has affected food and nutrition, and how new and sudden this advent is. then think of that every time you are making dietary decisions.
again, think on this thought: modern technology has made food available to me in this manner in the last few decades (centuries), but my body is adapted to a world millions of years before these conditions.
how much meat did i eat today? this week? this month?
how many animal products did i consume today and recently?
how many leafy greens did i eat today? this week?
how many fruits did i eat today? how diverse were they, and what colors were they?
how many other veggies have i been eating today and all week?
tubers? legumes? whole grains? think of these in context of the amount of protein and carbs youve consumed already.
at what point am i at through today's dietary profile? proteins? get enough unsat fats? am i close to or over the limit for saturated fat? carbs? fibers? vitamins and minerals?
to make this easier, pay attention to the nutrition in what you eat. learn what appropriate levels for the above are, and make mental notes all the time. it will become easy with enough constant thought, and you should always be giving your diet constant thought, as it is what becomes the physical you. it determines the greater part of your mood. your energy levels. your perception on the world. your health. your endurance. your awareness. in fact, it is a social obligation to be the healthiest you can be.
start now. what did you eat today...