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It’s three o’clock in the afternoon and you have a few more hours of work to wind up at the office before you head for home. Yet you think you can barely go on any longer.
You are drowsy and desperate for a nap. You reach for the donut you bought while you were out walking after lunch.
Sound familiar? Studies now suggest that is exactly the thing you should not be doing. Apparently it is protein, and not sugar, that keeps us up and alert.
Scientists at the University of Cambridge have found that protein activates the cells that are responsible for keeping us awake and help us burn more calories. These cells called orexin cells or hypocretins are basically a type of excitatory neuropeptide hormones.
Orexin cells or hypocretins are responsible for stimulating food intake, wakefulness and energy expenditure. Reduced activity of these special orexin cells causes narcolepsy as well as conditions of weight gain. (1)
The findings of the study were published in the scientific journal Neuron (November issue) has deeper implications in terms of understanding sleep disorders and obesity. It was found that orexin is affected by different nutrients to different degrees. Nutrients found in proteins such as egg whites stimulated orexin neurons more than other nutrients found in any other food.
We have always known that sleep patterns and health are intertwined with body weight, but now orexin cells which are affected by the type of food we eat also plug into the wakefulness and body weight issues.
Scientists were able to highlight the orexin cells which are usually hard to find and then introduced different nutrients to them and waited to see the resultant excitability of these cells. They found that amino acids stimulate orexin cells considerably.
It was particularly interesting because the same group of scientists had earlier observed that glucose blocks the orexin cells and thus the level of wakefulness reduces drastically. This had helped them explain post-meal drowsiness.