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Is Fasting Really Good For You?


In the news this week there have been stories about how fasting can help regenerate your entire immune system.

New research is showing that even just three days of fasting can kick start the body into a regeneration programme, producing new white blood cells which fight off infection.

There are health benefits for Muslims who take part in Ramadan, the month of fasting which marks the ninth month of the Islamic calendar

This information, from scientists at the department of Gerontology and Biological Sciences at the University of California, is being hailed by some as a breakthrough. The facility to induce the body to regenerate immune system cells would indeed be a major step. As we age, our natural immune systems become less effective, making us more susceptible to common diseases. Producing new white blood cells could counteract this. It could also be enormous beneficial for patients who have undergone chemotherapy which can damage an immune system.

There is a lot more testing and research to be undertaken, but it does endorse other reports on the benefits of fasting.

Professor Valter Longo, who is the director of the same university’s Longevity Institute, says one of the links between fasting and longevity seems to be a hormone called insulin-like growth factor 1 (IGF-1).

Professor Longo made a study of some villagers in Ecuador who have a natural genetic defect called Laron syndrome which gives them a lower level of IGF-1. These people smoke, eat a high calorie diet, but they don’t seem to suffer from cancer or diabetes.  “There are no reports, not a single one, of them ever dying of cancer,” he said.

Research from the University has shown that fasting can lower the levels of IGF-1 and also possibly be responsible for switching on a number of DNA repair genes. It could be that when a person runs out of food, the bodies changes from “growth” to “repair” mode.

But doctors including Professor Longo warns that fasting also causes other changes, such as a drop in blood pressure, a drop in glucose levels and metabolic reprogramming, so serious fasting really should be undertaken under medical supervision.

Shorter fasts, such as the daytime fasts taken during the month of Ramadan, can have beneficial results, according to Oxford’s Dr Razeen Mahroof.  He says that changes in the body depend on the length of the fast, explaining that a fasting state begins around eight hours or so after the last meal, when the gut has finished absorbing nutrients from the food.

Normally the body’s main source of energy is body glucose, which is stored in the liver and muscles. During a fast, this stock of glucose is used up first to provide energy, but when it runs out the body turns to fat as its source of energy. After a prolonged fast of many days, the body then might start using protein for energy which can involve the breakdown of muscle and other serious problems.

Dr Mahroof says the Ramadan fast, which only lasts from dawn to dusk, means it is a gentle transition from using glucose as the main source of energy to using fat. The body’s energy is replaced by pre-dawn and dusk meals and so the body doesn’t reach the stage of using protein for energy. He says the use of fat for energy can help weight loss which has a range of benefits.

Fasting is being hailed in some quarters as the new miracle activity for health benefits. But it is clear a lot more research needs to be done before we all start giving up essential food for any length of time.

There is an interesting booklet on fasting for Ramadan at:

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The above article is part of the features section of called laterlife interest. laterlife interest contains a variety of articles of interest for visitors to written by a number of experienced and new journalists.

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