Many grandmothers of today recall where olive oil was considered harmful to cholesterol, according to the doctrine of the time. With each new wave of healthy tips, marketing becomes a scientific hypothesis into a dogma of popular faith. Meanwhile, science continues to work, and sometimes grave dogma.
happened when you started demonstrate the benefits of the Mediterranean diet with olive oil as a prima donna, refuting his previous notoriety. And maybe now we are witnessing the end of another myth: that of the antioxidants that promise to give us more life and youth by getting rid of these vicious supervillains called free radicals.
At least that would, if it depended on the Sieg-fried Swiss biologist Hekimi. from the laboratory run by the Montreal McGill University (Canada), this researcher is studying the mechanisms of aging in the nematode Caenorhabditis elegans, a tiny worm that rivals the fruit fly Drosophila as a body pattern to study animal development . Hekimi changed its C.elegans to produce an abnormally large quantity of radicals llibres, which the classical theory because of envejcimiento. The researcher expected to see as the worms aged and died before the others, but was surprised to find that the effect was the opposite: more lived mutant nematodes. By adding vitamna C, the antioxidant more accessible, plus longevity that vanished.
The only possible conclusion to Hekimi, was one that contradicted the classical theory of aging by free radicals. This hpótesis lanazada by U.S. biotech Denham Harman in the 1950, dictates that aging is a consequence the progressive accumulation of free radicals, atoms or molecules with an unpaired electron in its outer shell that makes them very chemically aggressive.
These include highly reactive oxygen species such as peroxides and superoxide ions. These are created during the metabolism of oxygen in respiration, a process used to generate energy in the mitochondria. Antioxidants are also triggered by bombarding the cell with ultraviolet or ionizing radiation, cause oxidative stress and damage the DNA and other cellular components.
To verify their results surprising, Hekimi, mounted another test system. In this case submitted a normal gsanos to paraquat, a herbicide toxic to the European Union, which produces free radicals. The conclusion was the same. The scientist had no choice but to accept the maxim of Sherlock Holmes: when you have eliminated the impossible, whatever remains however improbable it must be true. And worms Hekimi, the truth was that free radicals, lengthening life. The experiments were published last December in PLoS Biology . Then the scientist joked with the effects of paraquat: do not try this at home.
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