Actually not much! In fact when you start to peel back the layers of information held in scientific papers it begins to reveal some even more uncomfortable truths.
Half a million years ago we had half the brain size we currently do. The growth of our brains in that time is due to us having found foods that allowed its growth â€“ namely proteins and fats. A lot of credit is attributed to eating fish for this growth. These are the food sources we were designed to eat, and in fact we knew carbohydrates were not, so what happened? Where did we start eating so much carbohydrate?
Up until 1941 it was widely accepted that a high protein and fat diet was a healthy one. We know this as the native Indians in the 1800â€™s were the tallest (this correlates strongly with overall health) and they survived on Bison meat alone.
Throughout arctic expeditions and many wars a product called pemmican was used as the nutritional source for these warriors. Pemmican was based on knowledge people reaped from looking at the native Indians health and comprised one third bison, two thirds fat.
Along comes Ancel Benjamin Keys who decided to shake the nutritional world and in 1952 took a study of 22 countries heart attack rates vs. saturated fat intake. What he actually did was threw away 16 points on a graph where he plotted them on x and y axis to demonstrate that an increase in heart disease was attributed to an increase in saturated fat in our diets.
These results were not a true reflection of his data, however people believed what he said and he became the founder of what we know as the lipid hypothesis. The basis of this hypothesis is fraudulent use of data by one man!
In 1977 the US government got behind this theory and said â€œReduce fat intake and replace it with healthy carbohydratesâ€ Americans followed this advice and they ate more and more carbohydrates and less and less proteins. At the same time the obesity rates and diabetic rates rose, yet despite all of this evidence, the US government wonâ€™t reverse its guidelines.
If you are healthy, the insulin drives the glucose from the carbohydrate breakdown into your muscles and liver where it is stored as glycogen and everything is fine. However there are some people who are unable to metabolise glucose well (carbohydrate intolerant) and eventually the glucose ends up in their fat cells.
These people end up gaining weight despite exercising and eating â€œwellâ€, although when placed on a high fat diet and the carbohydrate is removed, they lose weight.
In summary what appears to have happened is our normal appetite drive for fats has been replaced with an abnormal drive for carbohydrate which we canâ€™t regulate.