Apparantly there is research demonstrating that rapid evolution is occuring against onset diabetes. People who live in western cultures are undergoing natural selection for lower metabolisms to cope with typical western diets.
http://www.youtube.com/watch?v=dFILgg9_hrU
In the attached lecture around time index 1:01 Sapolsky talks about the difficulty in observing gradual changes and gives three examples of relatively fast evolutionary changes that have been succesfully observed. The second example is onset diabetes. We are often told how important it is to have a healthy fast metabolism and yet it seems that in the reality of western culture rapid metabolism is killing people and so we are adapting to the current reality and developing slower metabolism rates in each generation.
The third example is some guy in Siberia who wanted to sell fox fur and tried to make his life easier by breeding a tame version of this wild fox. Surely enough, the foxes became tame after 35 generations but they also became cute and cuddly and their fur changed completely and could not be sold. This proves that some charecteristics are tied to entire groups of characteristics and you can’t breed for just one characteristic without getting the entire package.
In other words, that’s what you get for trying to mess with nature!
This story led me to a myriad of interesting questions about the things people say and try to arbitrarily assert about what is a healthy human nutrition globally for all people on Earth – whether it be a typical western diet consisting of meat, dairy and eggs or vegetarian or vegan or raw food – many claim to have the one and only right answer for all humans everywhere and yet they don’t seem to agree on what that answer is.
I started wondering – what if the genes and receptors that determine the appropriate diet for any specific person are tied to a group of other genes and receptors? What other characteristics do these represent? Are there herbivore traits and carnivore traits that are shared across all species on Earth?
If I eat meat, and my offspring eat meat, will it activate or promote other traits that are found in carnivorous species? Likewise, if my offspring are vegeterian, will it promote herbivorous characteristics in them?
Is the typical western diet oppressing some dietary traits and promoting others?
For example, if people don’t have to run around, leap at their pray and pull it apart like they used to, would this not demote the group of carnivorous genes and receptors we have? On the other hand, how do the massive amounts of meat we consume in western diets affect this? Are we sending our bodies mixed evolutionary signals? Will this lead to some weird mutation or a dangerous disease?
All these questions lead me to think that perhaps there is no one right answer to what is “natural” for human beings around the world to eat.
On the individual level, certainly each of us has their own genes and receptors that are affected by our environment and inheritance. These don’t change so fast in the course of one lifetime. So I really can’t say to any individual what is the healthiest diet for them. I certainly can’t make broad generalizations that everyone, from a health standpoint, should be vegan or that everyone should eat meat, dairy and eggs to be healthy. I can only hope we come up with ways to individually measure this.
What I do believe can be extrapolated from all of this, and what I find beautiful – is that as a society, we can choose our diet, and given enough generations of evolution our bodies will adjust to whatever diet we choose. So in the long run, the choice whether to kill animals so that we may live is entirely up to us.
Who knows, perhaps if we eat enough cookies we might end up evolving into this?

The future of humanity?