This has taught me that only extremely healthy, attentive and energetic individuals can afford to go on a time-consuming vegetarian diet without becoming nutritionally deficient in the long run.
Unhealthy, innattentive and lazy individuals eventually become nutritionally deficient. You don't say?
it is clear that the majority of animals end their lives, not of old age, but of being eaten alive. Circle of Life thing.
Animals that are farmed for human consumption are treated as a commodity. A crop. A product manufactured for the profit of the producer. Not for the welfare of the animal, and definately not with the nutritional requirements of the consumer in mind. Circle of life has nothing to do with it. Neither does nutrition or sustainable practice. I'm not sure Animal Planet is the best place to go to understand this.
I consider a humanely, properly treated ranging domestic animal in a varied and interesting environment who is killed as fast as possible before being eaten as having had a more valuable life than a wild animal who goes through the whole eaten alive to death thing.
No matter what you've been told, the overwhelmimg majority of animals produced as a food are not treated humanely. They do not live in varied or interesting (whatever that means) environments. Their slaughter is dirty, painfull, bloody and drawn out. Are you really saying that domesticated food animals have more value than non domestic animals because we eat them? do you really mean that? Or are you having a brain fart?
A couple of other things....
Doctors, on the whole, know absolutely feck all about nutrition. Neither do hospital nutritionists. Thats why the budget for a hip replacement is about $20,000, and the budget to feed an in-patient during their recovery from illness in a hospital is about $2 a day.
Animal docummentaries on the whole, are not considered a reliable source of objective information about animals. Sorry, but thats just the way it is.