Carbohydrates are not importance for brain.

 You are bought chocolate  on exam or heard, as parents said for you, that  need to eat something sweet, thus brain will not work. Its deeply rooted myth, that gives more bad, than benefit. And fact, that brain contains 2 perc. From body mass, thus on 20 perc. On  his are necessary are all everyday energy expensive  . For  a doing own functions as base brain need in constant entering fuel. A brain can use are two base fuel :glucose and ketones.

Ketones are water dissolving connects , forming in splitting fatty acids, which brain can use for energy getting. Ketones are getting from fat ,which you are eating, or from a fat stocks of your organism.

In people's  moderately eating or with a high carbohydrate meal, and today such are much thus a base source for brain is glucose having .In peoples having low carbohydrate or ketogen  diet, brain receive a most big part of energy for a ketones calculation. And ,  from a physiological  point of view ketones are always being a most preferable and a full value meal for brain cells, than glucose. The system works by a following method:

1. After   24–28 hours without carbohydrates reserve source for energy is glycogen is exhausting, and level for insulin is falling/in high intensive trainings is happening faster/.

2. Liver reacts on the lowering level of insulin and increasing manufacturing ketones.

Better proof for brain ability to function   on ketones is being research, confirming ,that peoples are ability endure a full fasting for 30-60  days, keeping a normal functional activity. When are muscles and other importance structures of body, slowly loosing mass and function are on the long starving, brain a fill protected from exhausted catabolism of other body. That is all says about ,that when stocks of carbohydrates ending, in brain is having other source a fuel-are ketones. Also, ketones manufacturing in liver affecting a favourable on heart, kidneys and other organs, and researches found, that ketone diet is increasing for live duration. Strict limited carbohydrates  is ability to use and to cure epilepsy, worried disorders, Alzheimer disease, and diabetes second type, but about this detailed, I will post later.