Do you think it has long term effects on metabolism if you go keto temporarily for the quick losses? How about just low carb like the old Atkins diet?

#11 | POSTED BY JUSTAGIRL_IDAHO

I think it is likely that there are long term effects that we have not been able to discover yet.

I like to analyze things from an evolutionary perspective of "what did we evolve to do". In that case, we were stuck with the food that was naturally available to us at the time. During the spring it would have been a diet high in proteins and carbs, very little fat or sugar (seeds and vegetables and animals with depleted fat stores from the winter). That is the point at which our bodies would have been wanting to repair itself and build up muscle mass in anticipation of becoming active after the winter, as well as replenish any fats stores that had been depleted beyond what the body feels it needs as a reserve in times of "plenty". During the summer and into the fall the diet would gradually shift to higher and higher levels of sugars and fats. As that happens you would want your body to be adding to its fat stores in preparation for winter. So, when your diet is at its highest levels of both fats and sugars (simple carbs) you would want your body to be piling on the weight. Then, somewhat abruptly, fruits would disappear from the diet. And it would mainly be stored foods (rendered fat or smoked/dried meat are easiest to store) and hunted animals, as well as some complex carbs (roots and tubers). So, the diet would shift to a high proportion of fats and proteins with low amounts of complex carbs. At this point (the Keto diet) you would want to gradually LOSE weight so that your body (gradually and healthily) uses up its fat stores.

So, basically... complex carbs and protein = healthy body weight -> simple carbs and fat = gain weight -> protein and fat = lose weight.

If you goal is to lose weight, then Keto seems to be the best option.

And, I don't think it magically makes you burn more calories. Calories in = calories out. And your body is NOT going to waste them (especially if you are making it think it is "winter"). But, your body will probably adjust your APPETITE to take in less calories than it needs so that it loses weight. Just like your body will INCREASE your appetite if you eat a lot of simple sugars and fats to ensure that it TAKES IN more calories than it needs, thereby increasing fat stores.

But, the reason I think it will have long term health issues is because our bodies are designed to do different things at different times of the year. For example, it would not make sense on the Keto diet for the body to fully repair and/or rebuild accumulated damage in the body in the "winter" (on the Keto diet). That would use extra energy when you need to be saving it to ensure you have enough to get through the winter.

What biological processes that contribute to our health have come to rely upon the cycle of seasons and the macronutrients that those seasons enforce on us? I am skeptical that there are none. Which is why doing Keto for 6 months, or a year or five might look "healthy", but that in longer timeframes the body will start to suffer from the lack of the other "cycles".