Fasting – the secret of a long and healthy life

This column is written by Stig Bengmark – Professor Emeritus, scientist, lecturer and writer. Read more of Stig Bengmark’s columns here.

For 99.5% of our human existence on Earth, there were no fat people.

Jon Brower Minnoch lived in the United States between 1941-1983, and lived to be 42 years old. Jon became the heaviest person in human history. Jon, like millions of other people in the western world, committed state-sponsored ‘suicide’ with a knife and fork – which is completely possible due to the availability of cheap, refined and high-calorie agricultural products. His life was extremely miserable and his care cost society a very large amount of money. This is a common problem in western countries. Recently, it was reported in the UK that the direct cost of caring for obese people alone has risen by 350% over the past five years, which is extremely ominous for a country where the public health system is already in an economic crisis.

For millions of years, humans lived on a diet that, if translated to modern times, corresponds to what’s known as 80/10/10 – a diet completely dominated by flowers and leaves (80%) with elements of 10% high-fat fruits/vegetable fats (such as olives, avocados and coconuts) and 10% protein-rich peas, beans, lentils, nuts, almonds, seeds and the like. Consumption of fish and meat varied widely, but it was usually quite limited.

Obesity first appeared at the same time as industrial agriculture and has increased at the same rate as industrial agriculture has developed and its products have been refined. The epidemic of obesity and chronic diseases has its epicentre in the southern United States, in states such as Louisiana and Texas, and has so far mostly spread to agriculture-intensive countries such as Australia, New Zealand, Canada and even the United Kingdom. However, the title of Earth’s most obese and sick nations is soon expected to be taken over by the Arab world, especially Saudi Arabia and Kuwait, closely followed by India.

Early need for fasting.

As we know well, fasting is not a new phenomenon. The need to fast from time to time arose early on, both for spiritual reasons and for health reasons. As early as 1000-2000 BC, when the Old Testament was being written, we’re told how Moses fasted in the wilderness for 40 days. All religions include fasting, and now it has also penetrated into non-denominational circles as so-called detoxing. The best-known is the Muslim fasting month of Ramadan, and although one might have objections to the way it’s carried out, we have to accept the significant mental and physical improvements reported during and after the completion of Ramadan.

A limited intake of food – called calorie restriction (CR) – where you only eat about 2/3 of what you want either permanently or temporarily, has been shown to have significant health effects. Experiments on animals show as much as double life expectancy, significantly lower morbidity and significantly delayed onset of chronic diseases. And even though studies on humans are not yet as comprehensive as they could be, well-known researchers report significant progress in the application of CR on humans as well – lower risk for example, of getting cancer, diabetes and cardiovascular disease. In one US study, overweight people lost 1% of their weight per week, which is actually as good as the effects seen after surgical treatments. In addition, they avoided the side effects and disadvantages that are usually seen after so-called bariatric surgery.

In order to get the effect of CR, it seems it’s particularly important that protein intake is limited, and especially the intake of the amino acid methionine, which is most abundant in animal products.

A lot of diseases improve.

The following diseases – all related to the metabolism – have been shown to be strongly associated with degree of obesity/elevated BMI and can be expected to benefit significantly from a limited intake of calories (preferably permanently but also periodically).

* Increased inflammation in the body
* Too high blood pressure
* Too much fat in the blood – often called dyslipidemia (high ‘bad’ cholesterol (LDL), too low ‘healthy’ cholesterol (HDL), too many long-chain fatty acids)
* Type 2 diabetes
* Acute and chronic heart disease
* Stroke
* Bile-liver diseases
* Bone/joint diseases (osteoarthritis)
* Respiratory disorders in sleep (Sleep apnoea) and respiratory problems including asthma
* Some cancers (especially uterus, breast and colon)

Our forefathers fasted daily.

Health researchers are showing increasing interest lifestyles that are most reminiscent of those of our ancestors. These are still found in some remote parts of the world, such as Abkhazia in Georgia, Vilcabamba in Ecuador, and the Hunza district in northern Pakistan. People are rarely unwell here and a surprisingly large proportion of the population is over 100 years old. However, these residents do not practice periods of fasting – you could say that they fast every day in their own way. They rarely eat processed foods and those who do use dairy products, mostly the Abkhazians, consume their milk unpasteurised and with bacterial cultures. Vilcabambans and Hunzas are pretty much all vegans. The people here get by with on average 1,700-1,800 calories a day, even though they work long days in the fields. Compare this with what Scandinavian nutritional experts recommend: 1800-2400 for women and 2300-3000 for men (although a lot of people are consuming far more).


Okinawa, in Japan, was long known as the place on Earth with ‘the best’ health and longest life expectancy, but when the Americans built bases on the island after World War II and the inhabitants partially adopted their lifestyle, this changed radically – today the island’s health is among the worst in Japan’s 50 counties (prefectures).

When the gorillas at Cleveland Zoo, who had become obese on western diets, were allowed to eat a diet consisting of just romaine lettuce, endives, alfalfa hay, tree branches, beans, flax seeds and a banana dipped in multivitamins they lost 30 kg in around one year, and now weigh about the same as wild gorillas.

A few years ago, for two weeks, the BBC put 9 people on foods similar to the hunter-gatherers of old – mainly raw food with very little saturated fat, mostly broccoli, carrots, melons, figs, nuts, plums, radishes, bananas, strawberries, cabbage, tomatoes, watercress, apricots and mangoes, with a little bit of fish every now and then. The participants, who lost an average of 5 kg in weight, didn’t feel that they had lost any energy and they were in a good mood almost all the time. Just two weeks on the ‘ancestral diet’ brought lots of health benefits; several of their blood counts improved significantly, and their cholesterol level dropped by 23 percent, for example.

What are normal values for humans?

It is a very big problem for us that we don’t know which values are normal for humans. The values stated as being normal derive from measuring the mean value and current spread of the existing population. But let’s assume that everyone lives unhealthily, in which case, of course, all values become completely misleading. Taking, for example, cholesterol value, we know that it’s 30% lower among Chinese people living primitively in the countryside, and it’s another 30% lower among our closest ‘relatives’ – the chimpanzees. During the 100+ years that we’ve been able to follow the development of normal values, they’ve been raised gradually. A good example is normal birth weight – it alone has been adjusted upwards four times during the 20th century.

Listen to Walter Breuning – the world’s oldest man.

Walter Breuning from Great Falls, the man who lived for three centuries (1896 -2011) and became the world’s oldest man, has a lot to teach us. When asked about the secret to his long healthy life, Walter gave the following three pieces of advice:

* Be careful about what you eat and avoid eating too much
* Be sure to keep both your soul and your body active
* Imagine that today is a particularly good day and do you can everything to make it that way

Recommended reading: Campbell T & Campbell TC, The China Study: The Most Comprehensive Study of Nutrition Ever Conducted And the Startling Implications for Diet, Weight Loss, And Long-term Health, Benbella Books. USA 2006

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