Vitamin B3 may hold secret to a long, healthy life

Fountain of youth! Food supplement Vitamin B3 or niacin may be key to a longer and healthy life, a new study suggests.
Niacin tricks the body into believing that it is exercising, researchers said.
Scientists from ETH Zurich have demonstrated in roundworms that Vitamin B3 - also known as niacin - and its metabolite nicotinamide in the diet caused the worms to live for about one tenth longer than usual.
An international team of researchers headed by Michael Ristow, a professor of energy metabolism, has experimentally demonstrated, niacin and nicotinamide take effect by promoting formation of so-called free radicals.
"In roundworms, these reactive oxygen species prolong life," said Ristow.

This might seem surprising as reactive oxygen species are generally considered to be unhealthy.

Reactive oxygen species are known to damage somatic cells, a condition referred to as oxidative stress.
Based on the current and many previous findings he is convinced that small amounts of reactive oxygen species and the oxidative stress they trigger have a health-promoting impact, researchers said.
In earlier studies on humans, Ristow demonstrated that the health-enhancing effect of endurance sports is mediated via an increased formation of reactive oxygen species - and that antioxidants abolish this effect.
Based on the present study, he concludes that niacin brings about a similar metabolic condition to exercise.

"Niacin tricks the body into believing that it is exercising - even when this is not the case," said Ristow.
The researchers conducted their experiments on the model organism Caenorhabditis elegans.
The results of the study may also be of relevance for humans, as the metabolic pathway initiated by niacin is very similar in roundworms and higher organisms, said Ristow.
Niacin and nicotinamide have been approved as dietary supplements for decades. A whole series of foods naturally contain niacin, including meat, liver, fish, peanuts, mushrooms, rice and wheat bran.
Whether nutritional uptake is sufficient for a health-enhancing or lifespan-extending effect, however, remains to be demonstrated, said Ristow.

The latest study on the effects of niacin and nicotinamide is based on a particular class of enzymes, the sirtuins, which convert niacin into nicotinamide.
Moreover, they are also involved in gene regulation, helping to down regulate the activity of certain genes. Until today, scientists have been disputing whether sirtuins have a life-prolonging impact.
Ristow and his team's work now suggests that the activity of sirtuins actually prolongs life in roundworms.
According to the study, however, the life-prolonging effect is not down to gene regulation, as has often been supposed in the past. Instead, the effect is due to the conversion of niacin into nicotinamide.