FoodWritten by Chukwuma Muany

Do you want to live a healthy, long life with added benefit of better libido? Researchers have further validated claims that eating diet rich in fruits, vegetables, pulses, spices, whole grains, fish and olive oil, exercising regularly, praying and fasting frequently, losing the belly, cutting down on alcohol, quitting smoking and taking out time to laugh and dance can protect the human genetic material, Deoxy ribo-Nucleic Acid (DNA) from damage as well as boost performance in the bedroom. CHUKWUMA MUANYA writes.

Mediterranean diet increases life expectancy by protecting the DNA from damage

THE verdict is out: Mediterranean diet increases life expectancy by protecting the DNA from damage.

According to Wikipedia, the Mediterranean diet is a modern nutritional recommendation originally inspired by the traditional dietary patterns of Greece, Southern Italy, and Spain. The principal aspects of this diet include proportionally high consumption of olive oil, legumes, unrefined cereals, fruits, and vegetables, moderate to high consumption of fish, moderate consumption of dairy products (mostly as cheese and yogurt), moderate wine consumption, and low consumption of meat and meat products.

A research published last week in the British Medical Journal (BMJ) found that Mediterranean diet protects the DNA from damage and gives men a boost in the bedroom.

The researchers also found that with age, the telomeres, biological caps which are found at the ends of chromosomes that protect the DNA inside, become shorter but women who ate a Mediterranean diet had longer telomeres, and that these foods can also help men with impotence avoid a heart attack.

Harvard academics studied 4,676 middle-aged women comparing their typical eating habits with the make-up of their cells. Importantly, they looked at their telomeres – biological caps which are found at the ends of chromosomes that protect the DNA inside.

“As we get older, our telomeres get progressively shorter, causing the DNA to become damaged and raising the odds of age-related illnesses such as Alzheimer’ s, diabetes and heart disease,” the researchers wrote.

The research found that women whose diets were generally low in fat and high in fruit and vegetables had longer telomeres. But this was even more pronounced for those who followed a Mediterranean diet rich in fruit, vegetables, nuts and pulses.

The lead author from the Brigham and Women’s hospital in Boston, the United States (US), Marta Crous-Bou, said that it may be due to antioxidants in fruit, vegetables and nuts – chemicals that prevent ill health and ageing.

She said: “Our findings showed that healthy eating, overall, was associated with longer telomeres. However, the strongest association was observed among women who adhered to the Mediterranean diet.”

Associate professor at the Harvard School of Public Health, Dr Immaculata De Vivo, said: “Our results further support the benefits of adherence to this diet to promote health and longevity.

“To our knowledge this is the largest population-based study specifically addressing the association between Mediterranean diet adherence and telomere length in healthy, middle-aged women.

“Our results further support the benefits of adherence to this diet to promote health and longevity.”

Previous research by Harvard University last year involving 10,000 showed that women who followed a Mediterranean diet were 40 per cent to live beyond the age of 70.

They were also far less likely to develop chronic diseases including diabetes, heart disease, Alzheimer’s or Parkinson’s disease.

The Mediterranean diet not only improves heart health but it could help male impotence.

Researchers found men with erectile dysfunction who adopted the diet – involving eating fruit, vegetable, pasta, olive oil and nuts daily but few dairy products or red meat – may reduce their chances of having a heart attack or stroke.

However, patients with erectile dysfunction who failed to stick to the Mediterranean diet had more vascular and cardiac damage.

Greek Doctor, Athanasios Angelis, who presented his findings at the annual meeting of the European Association of Cardiovascular Imaging in Austria, said: “Erectile dysfunction is not a symptom of ageing, it is a bad sign from the body that something is wrong with the vasculature.

“In 80 per cent of cases, erectile dysfunction is caused by vascular problems and is a warning that patients are at increased risk of a heart attack or stroke.”

He added: “The Mediterranean diet is associated with lower cardiovascular events and could be a way to help erectile dysfunction patients lower their risk. We wanted to investigate whether patients with erectile dysfunction who follow this diet have less vascular and cardiac damage.”

The study included 75 men with erectile dysfunction, average age 56, who attended the Department of Cardiology at Hippokration Hospital in Athens.

Angelis said: “Patients with erectile dysfunction who had unhealthy diets had more vascular and cardiac damage than those who followed the Mediterranean diet. Good sources of monounsaturated fat – such as macadamia nuts – can help men with erectile dysfunction avoid a heart attack

“Previous studies have shown that patients with erectile dysfunction have vascular damage, but we found that the heart is also damaged. This may help to further explain why these patients are more prone to cardiovascular events. The formation of atheroma, the stiffening of the arteries, and the poor functioning of the heart can eventually lead to a cardiac event.”

He added: “Our findings suggest that adopting the Mediterranean diet can improve the cardiovascular risk profile of patients with erectile dysfunction and may reduce their chances of having a heart attack or stroke. This needs to be tested in a larger study.

“Really simple changes in our diet may help a lot, for example using olive oil which contains monounsaturated fat. If someone doesn’t have the money to buy some of the foods they can substitute them with others, for example nuts are a good source of monounsaturated fat.

“Sometimes it’s difficult to adopt something if you consider that it’s part of a prescription, but the Mediterranean diet is not a prescription, it’s a lifestyle. It’s about having an awareness of what foods are healthy or unhealthy.”

He concluded: “Patients who have erectile dysfunction and don’t adhere to the Mediterranean diet have vascular and cardiac damage and are at increased risk of heart attack and stroke.

“Our findings suggest that adopting a healthy diet can reduce that risk. We also advise patients to stop smoking, exercise and ensure that they have healthy levels of blood pressure and lipids.”

Leafy vegetables cut risk of degenerative diseases like diabetes, heart attack, cancer, stroke 

Nigerian and British researchers have confirmed that high intake of local vegetables can prevent, correct or treat health disorders such as diabetes, cancers, arthritis, obesity, high blood pressure, haemorrhoids/pile, gallstones, stroke, among others.

Experts say leafy vegetables cut the risk of developing degenerative diseases. From Telferia occidentalis (fluted pumpkin, ugu in Ibo) to Amaranthus hybridus (popularly called amaranth or pigweed, inine in Ibo, tete in Yoruba), the story is the same. Not to mention the local delicacy, edikaikong soup, which is sometimes made with no fewer than five different vegetables.

Nigerian researchers led by a professor of pharmacognosy at the University of Lagos, Olukemi Odukoya, have confirmed the potential of 21 Green Leafy Vegetables (GLV) in the cooked form as natural antioxidant supplement diets.

The study titled “Antioxidant Activity of Selected Nigerian Green Leafy Vegetables,” was published in Science Alert.

Odukoya assessed the antioxidant activity of hot water extracts of the GLV of Amaranthus hybridus (green amaranth or pigweed, inine in Ibo, tete abalaye in Yoruba), Amaranthus caudatus (slim amaranth, inine oyibo in Ibo, tete oyinbo in Yoruba), Beilschmedia manni (vegetable, atiokwo), Celosia argentea variety argentea (cockscomb, green soko in Yoruba), Celosia argentea variety cristata (cockscomb, red soko in Yoruba), Corchorus olitorius (jute, ewedu in Yoruba), Crassocephalum crepidioides (fireweed or thickhead, ebolo), Gnetum bucholzianum (koko vine, okazi in Ibo and afang in Ibibio), Gongronema latifolium (utazi in Ibo), Heinsia crinita (atama), Hibiscus callyphyllusrocks hibiscus, isapa in Yoruba), Lasianthera africana (editan in Yoruba), and Myrianthus arboreus (giant yellow mulberry, ujuju in Yoruba).

Others include Pterocarpus mildbraedii (oha in Ibo), Pterocarpus santalinoides (red sandalwood, nturukpa in Ibo), Solanum macrocarpon (African egg plant, igbo in Yoruba), Solanum melongena (egg plant, afufa in Ibo and igba in Yoruba), Struchium sparganophora, Talinum triangulare (water leaf), Telfaria occidentalis (fluted pumpkin, ugu in Ibo), and Vernonia amygdalina (bitter leaf, onugbu in Ibo and ewuro in Yoruba).

Odukoya concluded that high consumption of vegetables containing phenolic antioxidants might slow down the process of degenerative diseases. She wrote: “For the selection of superior indigenous vegetables, evaluation of antioxidant activity, ascorbic acid content and total phenols can be used as an index. This study recommends more consumption of these vegetables because of their potential health benefits.”

Also, British researchers have found that spinach, broccoli, cabbage, kale and even lettuce contain the beneficial chemical nitrate, which can reach all parts of the body.

In three independent studies they found leafy green vegetables can thin the blood, ensuring oxygen is delivered efficiently around the body and cutting the risk of dangerous clots, stroke and heart attacks.

Nitrate, which is also found in beetroot, also sets off a chain reaction that widens and opens blood vessels and converts bad white fat cells into good brown, fat-burning cells, which can combat obesity and type 2 diabetes.

The findings suggest people may be able to alter the thickness of their blood through simple changes in their diet, which could be important for patients with cardiovascular diseases.

Sufferers may be able to improve their quality of life through simply introducing more nitrate rich vegetables into their diet.

The studies from the Universities of Cambridge and Southampton, part-funded by the British Heart Foundation (BHF), were published last week.

Researcher, Dr. Tom Ashmore, said: “The best thing about nitrate is that it is not expensive, treatment is not invasive and not much is needed to observe a significant effect. The only downfall is some people don’t like vegetables.”

Ashmore led a study showing how eating more nitrate rich vegetables like spinach, and lettuce such as rocket and iceberg, can reduce the production of a hormone, called erythropoietin, made by the kidneys and liver.

This hormone determines production of red blood cells, which increase oxygen levels and the thickness of blood.

However, an over-supply of cells can harm those suffering from altitude sickness and heart patients, who may actually have oxygen starvation caused by the blood being too thick to penetrate vital organs.

The new study shows eating more green vegetables could alleviate some of the debilitating symptoms of damaged hearts, by cutting erythropoietin levels and reducing the production of red blood cells.

The study was published in the Journal of the Federation of American Societies for Experimental Biology.

Dr. Andrew Murray from Cambridge University, who co-led the study, said: “Here we show that nitrate from the diet can help regulate the delivery of oxygen to cells and tissues and its use, matching oxygen supply and demand.

“This ensures cells and tissues in the body have enough oxygen to function without needing to over produce red blood cells, which can make the blood too thick and compromise health.

“Lowering the blood’s thickness without compromising oxygen delivery may also help prevent blood clots, reducing the risk of a stroke or heart attack.”

Prof. Martin Feelisch, from Southampton University of Southampton, said: “These findings suggest simple dietary changes may offer treatments for people suffering from heart and blood vessel diseases that cause too many red blood cells to be produced.

“It is also exciting as it may have broader implications in sport science, and could aid recovery of patients in intensive care by helping us understand how oxygen can be delivered to our cells more efficiently.”

A second study in The Journal of Physiology, shows that consuming nitrate by eating a few more leafy greens or beetroot, could protect vital proteins in heart cells and increase a compound that causes blood vessels to widen, allowing the heart to pump more efficiently.

In a third study, published in Diabetes, the researchers identified nitrate’s ability to stimulate conversion of white, or bad, fat cells into beige cells in a process called browning.

Beige cells are more similar to ‘good’ brown fat cells and burn fat to produce heat, suggesting that simple dietary changes could reduce the number of bad white fat cells we have, reducing the risk of obesity and type 2 diabetes.

Murray, who worked on all three studies, said: “These studies represent three further ways in which simple changes in the diet can modify people’s risk of type 2 diabetes and obesity as well as potentially alleviating symptoms of existing cardiovascular conditions to achieve an overall healthier life.”

Five lifestyle changes to extend life span

Researchers claim Most heart attacks in men could be avoided by making five simple lifestyle changes.

Losing the belly, cutting down on alcohol, walking for 40 minutes a day, eating more fruit and vegetables and quitting smoking would drastically lower their risk.

A study of 20,271 men found that four out of five heart attacks could have been prevented by taking these five basic steps.

Swedish researchers found that four out of five men could reduce their risk of heart attacks by making lifestyle changes like stopping smoking, taking exercise, switching to a healthy diet and drinking alcohol moderately. Even making one change reduced their risk by up to a third – and if they made all five changes, their risk fell by 86 per cent.

Stopping smoking cut the risk by 36 per cent and a healthy diet did so by 25 per cent. Drinking less than three units – or one-and-a-half pints – a day led to an 8 per cent fall.

Having a waist measurement of less than 38in reduced the risk by 13 per cent, while walking or biking for at least 40 minutes a day cut it by 7 per cent. The more changes the men made, the greater the reduction in risk.

For example, if they ate a healthy diet and drank less, their risk went down by 35 per cent.

If they exercised, followed a healthy diet and reduced their drinking, it fell by 64 per cent, according to the study published in the Journal of the American College of Cardiology.

The researchers, from Sweden, calculated that 80 per cent of heart attacks in men could be avoided through these changes.

The researchers tracked the men – all aged 45 to 79 – for 11 years. At the beginning of the study, they answered a series of questions about their lifestyle.

Obesity knocks 20 years of good health off your life and can accelerate death by eight years

However, scientists warn that being obese can shorten life by eight years and blight up to two decades with ill-health.

They used a computer model to predict the lifelong toll of being overweight. Their calculations show that diabetes and heart disease are set to deprive an obese person of up to 19 years of healthy living.

For the very obese, with a Body Mass Index (BMI) of 35 or more, between one and eight years of life were likely to be lost. Overweight people with BMI scores of 25 to 30 were predicted to have their lives shortened by up to three years.

Body mass index (BMI), a measurement relating weight to height, is used to assess whether an individual is overweight.

A healthy or normal weight is a BMI score of 18.5 to 24.99 – above that is a sliding scale to life-threatening fatness.

Between 25 and 29.9 is defined as ‘overweight’ and a BMI over 30 is defined as clinically obese, although the result may be misleading for sportsmen and women, and pregnant women.

A BMI of 35-plus is described as ‘morbidly obese’.

Lead researcher Professor Steven Grover, from McGill University in Montreal, Canada, said: “Our computer modelling study shows that obesity is associated with an increased risk of developing heart disease and stroke, and diabetes.

“This will, on average, dramatically reduce an individual’s life expectancy and the healthy life-years free from living with these chronic illnesses compared with people of normal weight. The pattern is clear.

“The more an individual weighs and the younger their age, the greater the effect on their health, as they have many years ahead of them during which the increased health risks associated with obesity can negatively impact their lives.”

The effect of excess weight on cutting life short was greatest for the young and fell with increasing age, says the study published in The Lancet Diabetes & Endocrinology journal.

The new study analysed the contribution of being overweight and obese to years of life and healthy living lost in adults aged between 20 and 79.

Living longer by eating less

Scientists have known since the 1930s there was only one real proven way in which you can extend the lifespan of an animal in laboratory conditions (up to 30 to 40 per cent longer). That way was through reducing the daily calorie intake dramatically (up to 40 per cent) compared to others fed at the normal calorie level. This is known as calorie restriction (or CR for short).

The CR groups were noted to have decreases in blood pressure, fasting insulin, inflammation, triglycerides, total cholesterol, and body mass. All markers to say that the ageing process is slowed down including more protection at the cell level against diseases.

Unfortunately there is also downsides to the CR approach including loss of lean muscle (and getting really skinny), loss of energy, being hungry, loss of mental focus and well-being, increases in anxiety/depression/irritability, and just nothing that any of us would really want to go through.

Later on it was discovered that another protocol involving fasting/feeding reduced calories every other day could be used to mimic the health benefits seen in a fulltime CR approach.

Long-life secrets from 115-year-old woman

The secret to a longer life may be discovered in the body of one of the world’s oldest humans.

When Hendrikje Van Andel-Schipper donated her body to science, she gave longevity researchers a truly special gift.  She was the oldest person in the world when she died at age 115, and her body, in the hands of a team of Dutch researchers, launched a slew of breakthrough investigations into why some people live longer than others.

In 2010, scientists led by Dr. Henne Holstege at the VU University Medical Center in Amsterdam sequenced Andel-Schipper’s genome with the hope they would uncover something about the secrerts of longevity from her genes.

In Holstege’s latest study, published in the journal Genome Research, the researchers looked for gene mutations in Andel-Schipper’s blood. When stem cells divide, they generate different types of blood cells, like white blood cells. But these divisions can also cause mutations. They wanted to determine whether mutations can occur in healthy white blood cells over time, and if they have any impact on health. They discovered that although she was a mostly healthy person, there were hundreds of genetic mutations in her cells, which they thought was curious. So the researchers explored where these white blood cells were coming from, and took a look at her stem cells.

Scientists estimate that everyone starts their life with about 20,000 stem cells, 1,300 of which are considered “active.” To the researchers’ surprise, Andel-Schipper only had two active stem cells at the time of her death. “At first I could not believe that it was true. I thought it must be a technical error. It cannot be true that this person can still be alive with two stem cells,” says Holstege.

The researchers then looked at the length of the telomeres on Andel-Schipper’s blood cells and discovered they were extremely short compared to all her other organs. As cells age, their telomeres get shorter. Therefore, the researchers realized that there may be a limit to the number of divisions our stem cells can make, and that at a certain point, they must start to die from division exhaustion. It’s possible that stem cell exhaustion was the cause of death of Andel-Schipper, and that it could also be the cause of death among many people who live to great ages, although the researchers acknowledge that more research needs to be done to determine whether this holds true.

If proven, the implications for aging are significant. If there’s a limit to the life of stem cells, that’s a limit to human life. But what if you could replenish them?

Laughter is the key to a longer life: Individuals who live to 100 tend to be relaxed, optimistic

Having an optimistic, carefree personality may be linked with a longer life, according to a new study of centenarians published in the journal Aging.

As part of its Longevity Genes Project, researchers at the New York-based Albert Einstein College of Medicine surveyed 243 individuals of Eastern European-Jewish descent who were at least 95 years old.  The survey was designed to assess the participants’ personality traits.

Based on the survey findings, the researchers determined that the majority of individuals who reach 100 years old—about 0.2 per cent of the United States (U.S.) population- are relaxed, friendly, conscientious, and optimistic. They also have an easy laugh and an active social life.

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Centenarians did not tend to display neuroticism. Moreover, they did not ignore issues; rather they often addressed feelings as they arose.

The findings provide further evidence that people “should do what they can to manage their stress better so that it doesn’t manage them,” says Thomas Perls, who leads the New England Centenarian Study at Boston University Medical Center.

He notes that stress can contribute to conditions like cardiovascular disease and extroversion can help create networks of friends, which keep the elderly cognitive engaged. “People usually know what activities help them relieve stress. Like exercise, yoga, tai chi, laughing a lot, reading, or art activities,” according to Perls. He added, “It’s just a matter of setting aside the time and energy to do these things.”

Exercise is best prescription for good health and a long life

An apple a day keeps the doctor away, so the saying goes. But it appears that if we try to be more scientific about it, exercise is what can help keep your health in tip-top condition. As more research is conducted into the link between exercise and the prevention of various diseases, doctors are increasingly recognising the importance of prescribing physical activity to their patients as a way of both treating and averting illness.

“I recommend exercise to my patients all the time,” says Jennifer Kasirsky, a consultant obstetrician and gynecologist at Welcare Hospital in Dubai. “It is extremely important and can make a world of difference to your mental and physical health.”

More and more studies are revealing the benefits of frequent exercise on your health. For example, it was found that active individuals in their 80s have a lower risk of death than inactive individuals in their 60s. Regular physical activity can also reduce mortality and the risk of recurrent breast cancer by approximately 50 per cent, lower the risk of stroke by 27 per cent and reduce the incidence of heart disease and high blood pressure by 40 per cent.

Exercise is Medicine, a multi-organisational initiative coordinated by the American College of Sports Medicine, is focused on promoting the importance of prescribing exercise when designing treatment plans for patients. Its vision is to make physical activity and exercise a standard part of disease prevention and treatment. It states that research has proven that exercise improves the quality of life and reduces the incidence of disease, chronic health conditions and obesity.

A recent report found that one in three women received an exercise prescription to treat or prevent conditions including high blood pressure, diabetes and even cancer. But what is it that makes exercise a potential cure for these ailments?

According to Safeek Ali, a dietician at the Welcare Hospital in Dubai, regular exercise – especially aerobic exercise – can strengthen your heart and cardiovascular system, improve your circulation, increase your energy levels so that you can do more activities without becoming tired or short of breath, lower blood pressure, help reduce body fat, stress and depression and improve sleep.

Ali explains how exercise lowers the risk of heart disease. “Health research scientists say when a person exercises, the heart muscle contracts forcefully and frequently, increasing blood flow through the arteries. This leads to subtle changes in the autonomic nervous system, which controls the contraction and relaxation of these vessels. This fine-tuning leads to a lower resting heart rate [fewer beats to pump blood through the body] and lower blood pressure – all factors that lower the risk of developing cardiovascular disease,” explains Ali.

Ali also says that several studies show that regular exercise and a healthy diet lowers the risk of certain cancers. “Researchers say exercise may ward off cancer and other diseases because it appears to beef up the body’s immune system. Exercise may also help reduce levels of the female hormones oestrogen and progesterone in the blood, potentially also lowering the risk of developing breast and uterine cancers linked to high levels of those hormones,” says Ali.

Other research suggests that mild depression and anxiety can be treated with a combination of exercise and Omega-3 supplements. Kasirsky says that while the link between anxiety, depression and exercise isn’t entirely clear, working out can definitely help you to relax and feel better.

“Exercise is believed to help ease depression by releasing neurotransmitters and endorphins that make you feel good, reducing immune system chemicals that can worsen the condition, and by increasing the body’s temperature, which may have calming effects,” says Kasirsky.

“Exercise can also help you gain confidence through meeting goals and challenges. Getting into shape can make you feel better about your appearance, take your mind off worries and give you the opportunity for more social interaction,” she says.

If you’re lucky enough to have good health and are looking to maintain it, the experts advise that you should definitely exercise regularly. Hanan Wehbi, a Dubai-based personal trainer and nutritionist, says that while exercising every day is harmless, it is inconvenient for a lot of people.

“Three to four times a week is perfect,” says Wehbi. “The type of exercise, however, varies with age and health condition. If a person is young and healthy then high intensity interval training is recommended regularly. However, if a person is suffering from an illness or is of an old age, the exercise should be under the supervision of a certified trainer who knows the condition of the person very well to avoid any injuries and prevent the illness from causing diverse effects,” says Wehbi.

Housework may lengthen your life—but it depends on intensity

Three new studies suggest that individuals who stay active through “intense” but mundane activities—whether it’s mowing the lawn or painting the house—live longer than those who are active longer but perform less intense activities, such as washing the dishes.

A Centre for Research in Epidemiology & Population Health study on civil servants in England found that servants who regularly engaged in activities such as painting their homes, making household repairs, and walking briskly lived the longest. Meanwhile, civil servants engaged in milder activities—such as washing dishes—lived longer than their sedentary counterparts, but not as long as those who participated in more intense, but briefer chores.

A Bispebjerg University Hospital study on 5,106 individuals who reported regularly riding their bicycles for about 18 years found that those who rode more intensely lived longer than those who rode at an easy pace, even if they did so for longer. On average, cyclists who regularly rode at an intense pace lived about four or five years longer than those who went at a more leisurely pace for a longer period of time.

A study from the National Cancer Institute found that “maximum longevity was reached at a physical activity level equivalent to 65 minutes per day of walking, with no evidence for gains above this level of activity.” Individuals who met government exercise recommendations lived 3.4 years longer than those who did not exercise, while those who engaged in a very low level of activity for just 10 minutes a day increased their life expectancy by almost two years.

Fasting for three days can regenerate entire immune system

Fasting for as little as three days can regenerate the entire immune system, even in the elderly, scientists have found in a breakthrough described as “remarkable”.

Although fasting diets have been criticized by nutritionists for being unhealthy, new research suggests starving the body kick-starts stem cells into producing new white blood cells, which fight off infection.

Scientists at the University of Southern California say the discovery could be particularly beneficial for people suffering from damaged immune systems, such as cancer patients on chemotherapy.

It could also help the elderly whose immune system becomes less effective as they age, making it harder for them to fight off even common diseases.

The researchers say fasting “flips a regenerative switch” which prompts stem cells to create brand new white blood cells, essentially regenerating the entire immune system.

“It gives the ‘OK’ for stem cells to go ahead and begin proliferating and rebuild the entire system,” said Prof Valter Longo, Professor of Gerontology and the Biological Sciences at the University of California.

“And the good news is that the body got rid of the parts of the system that might be damaged or old, the inefficient parts, during the fasting.

“Now, if you start with a system heavily damaged by chemotherapy or ageing, fasting cycles can generate, literally, a new immune system.”

Prolonged fasting forces the body to use stores of glucose and fat but also breaks down a significant portion of white blood cells.

During each cycle of fasting, this depletion of white blood cells induces changes that trigger stem cell-based regeneration of new immune system cells.

In trials humans were asked to regularly fast for between two and four days over a six-month period.

Scientists found that prolonged fasting also reduced the enzyme PKA, which is linked to ageing and a hormone which increases cancer risk and tumor growth.

“We could not predict that prolonged fasting would have such a remarkable effect in promoting stem cell-based regeneration of the hematopoietic system,” added Prof Longo.

“When you starve, the system tries to save energy, and one of the things it can do to save energy is to recycle a lot of the immune cells that are not needed, especially those that may be damaged,” Dr Longo said.

“What we started noticing in both our human work and animal work is that the white blood cell count goes down with prolonged fasting. Then when you re-feed, the blood cells come back. So we started thinking, well, where does it come from?”

Fasting for 72 hours also protected cancer patients against the toxic impact of chemotherapy.

“While chemotherapy saves lives, it causes significant collateral damage to the immune system. The results of this study suggest that fasting may mitigate some of the harmful effects of chemotherapy,” said co-author Tanya Dorff, assistant professor of clinical medicine at the USC Norris Comprehensive Cancer Center and Hospital.