These branched amino acids dominate in the composition of muscle fibers. Their penetration into the muscle is promoted by insulin. They are necessary for muscle anabolism.
But leucine, isoleucine and valine are also competitors for the cerebral passage of tryptophan .
Excessive meat consumption is therefore a source of worsening of high drive tension, poor drive control, impulsivity, aggressiveness,
attraction to fast sugars, alcohol, tobacco, all serotonergics, etc.
in summary of most self-destructive behaviors, accelerators of aging, which increase the risk of overweight, cardiovascular disease, cancer and even accidents.
And leucine is the amino acid the most effective at activating the mTOR nutrient sensor, a pro-inflammatory pathway whose activity has the opposite effects of calorie restriction and which reduces longevity.
Leucine not only opposes the passage of tryptophan through the brain, but also its absorption from the intestines. However, tryptophan is the rarest amino acid of all.
Tryptophan therefore not only gives serotonin in the brain, but also – via the hepatic route known as kynurenins – nicotinamide, which is a major limiting factor
- recycling of glutathione
- the activity of sirtuins, all NAD dependent
- DNA repair activity, especially poly ADP ribosylation
The deficiency in nicotinamide or vitamin PP (preventive pellagra) gives pellagra which associates dermatitis (in fact a generalized inflammation), diarrhea and serious mental disorders.
Pellagra appeared in Veneto, where the Italians, the first European importers of New World corn (polenta), rich in leucine, inhibitor of the absorption of tryptophan .
But, without making pellagra, the simple reduction in the availability of NAD is a major factor in early aging, inflammatory and psychiatric pathologies (already with an impact on cerebral serotonin), decrease in DNA repair, of cancers …
Nicotinamide appears today, along with magnesium and polyphenols, as one of the major nutrients in the prevention and treatment of numerous pathologies, in particular inflammatory and degenerative.
Author Jean-Paul Curtay