Bears, like true omnivores, eat bugs and fruits and animal flesh and grass and practically anything to fill their bellies. Bears also, like true omnivores, can't get atherosclerosis from things they consume.
Humans, feeding on primarily fat based diet get atherosclerosis very often. Best epidemiological/history research on that topic is done on Inuits where remains of children showed atherosclerotic plaques in the vessels - their diet, although not ketogenic, contained mostly animal fats and proteins. Other mechanistic studies proved that direct causal mechanism exists but the same thing happens also with sugary diet, or essentially any diet with a caloric surplus (highest effect of course with highly caloric diets or diets rich in cholesterol over long timespans).
Essential fatty acids (omega-3 and omega-6), on the other hand, are abundant in animal flesh (if we ignore plant oils). Human reliance on these sources definitely implies we are omnivores but with a certain complex twist.
Given the young age of nutrition science, lack of personalized methods, and flawed epidemiological studies (for example, epidemiological studies condemning meat and dietary cholesterol ultimately fail, on the other hand, studies showing that dietary cholesterol has no effect on basline cholesterol are methodologically flawed), a skeptic would conclude we still know little when it comes to long consistent living and the effect of diet on health. We do know a lot about intervention on sick people though. Practically any diet that is more healthy than a diet sick people practice works, best one being the one with highest nutrient to calories ratio (foods that have huge volume but low calories tend to have that characteristic and its mostly just plants - hard to overeat and create a caloric surplus), which is a plant-based diet. Still, it's questionable how this works long term (what's the source of fatty acids? where's B12 etc.).
I've read studies that discuss excess cellular energy as the cause of metabolic disease, but are there any studies on athletic people eating high calories over long periods? That is, would Michael Phelps' 10k calorie per day cause a problem, even if he uses all 10k? Because there would be spikes unless one is meticulous about eating small meals over the day.
Humans, feeding on primarily fat based diet get atherosclerosis very often. Best epidemiological/history research on that topic is done on Inuits where remains of children showed atherosclerotic plaques in the vessels - their diet, although not ketogenic, contained mostly animal fats and proteins. Other mechanistic studies proved that direct causal mechanism exists but the same thing happens also with sugary diet, or essentially any diet with a caloric surplus (highest effect of course with highly caloric diets or diets rich in cholesterol over long timespans).
Essential fatty acids (omega-3 and omega-6), on the other hand, are abundant in animal flesh (if we ignore plant oils). Human reliance on these sources definitely implies we are omnivores but with a certain complex twist.
Given the young age of nutrition science, lack of personalized methods, and flawed epidemiological studies (for example, epidemiological studies condemning meat and dietary cholesterol ultimately fail, on the other hand, studies showing that dietary cholesterol has no effect on basline cholesterol are methodologically flawed), a skeptic would conclude we still know little when it comes to long consistent living and the effect of diet on health. We do know a lot about intervention on sick people though. Practically any diet that is more healthy than a diet sick people practice works, best one being the one with highest nutrient to calories ratio (foods that have huge volume but low calories tend to have that characteristic and its mostly just plants - hard to overeat and create a caloric surplus), which is a plant-based diet. Still, it's questionable how this works long term (what's the source of fatty acids? where's B12 etc.).