The set of health factors (positive and negative) linked to these three areas is really very large.
Overweight, metabolic pathologies and a sedentary lifestyle not only increase the risk of pathologies, accidents and death or disability, but also reduce cognitive efficiency and anticipate nervous degeneration by promoting aging.
What we will talk about, however, has nothing to do with cardiovascular health or the fatty acid composition of central nervous tissue.
In fact, in the following article, we will focus on a very particular aspect, namely the direct, genetically mediated relationship between negative caloric balance (low calories) and longevity.
to the intake of resveratrol - a non-flavonoid phenol contained in red wine, studied for its hypothetical role in the "French paradox" - it seems that SIRT1 is activated significantly even in the case of caloric reduction.
As the lead author of the study, Li-Huei Tsai, of the "Howard Hughes Medical Institute" pointed out, in mouse models, the protein for which this gene encodes appears:
- enormously increase neural connections, synaptic plasticity and memory formation;
- reduce neuro-degeneration;
- prevent learning difficulties.
Recent studies had already linked SIRT1 to brain physiology and neurological disorders but, before Tsai's discovery, the role of this gene was unknown.
SIRT3 and SIRT4
Scientists have known for many years that one diet a low calorie content prolongs life by at least one third; however, prior to the discovery of the SIRT3 and SIRT4 genes, no one had been able to understand the molecular mechanism involved.
According to a study conducted by David Sinclair, associate professor of pathology at "Harvard Medical School", in collaboration with researchers from the "National Institute of Health" of the "Cornell Medical School", SIRT3 and SIRT4 are associated with longevity because capable of safeguarding cells from certain types of stress - such as that of calorie restriction, in the presence of which they are activated - and from the diseases of aging.
The discovery of the two new genes confirmed that mitochondria are the primary energy source of cells and are essential for maintaining their health and longevity.
When the efficiency of the mitochondria begins to decrease, the "energy" goes out of the cells, which begin to die.
Mitochondrial DNA (mtDNA) is so important that even if all the energy sources within it, including the nucleus, were missing, with the mitochondria remaining viable and functional, the cell would still be able to survive.
SIRT3 and SIRT4 maintain the vitality of mitochondria; for this they make the cells healthy.
According to the study, when a diet is started, the cells begin to suffer from calorie restriction and this stressful situation is signaled through the cell membrane.
The signal reaches and activates the NAMPT gene which, at high concentrations, increases the levels of NAD which tends to accumulate in the mitochondria.
This series of reactions causes the mitochondria to grow stronger, which increases energy output and the cellular aging process slows down significantly.
The same process is activated by physical exercise.
Sinclair explains: "We are not yet sure what is the particular mechanism that is activated by the "increase in NAD levels, but we have found that when it comes into action, programmed cellular suicide subsides.'.
According to the researcher, SIRT3 and SIRT4 could become targets for anti-aging drugs and associated diseases.
, it becomes deductible that it is required at least to follow a normal calorie diet and to remain in normal weight - eventually, to lose weight if necessary.But how do you get less energy? By eating less? It depends.
In old age it might be inadvisable; or better, if the diet is well distributed and balanced, reducing the caloric intake could lead to unwanted weight loss and the failure to reach important nutrients such as certain minerals, vitamins, essential omega 3 fatty acids and proteins with a high biological value.
On the other hand, it is much more sensible to increase the level of general physical activity, preferably with a motor component with a higher intensity than simple walking. In this way, not only is it possible to manage the caloric balance without reducing food portions, but positive cardio-vascular, respiratory and metabolic adaptations are obtained, and a protective action on the nervous system and on the mood.
