Eat to Your Heart’s Content — Part 3

Chapter 9: Eat to Your Heart’s Content

The question is whether we should be fasting throughout our lives to access these beneficial effects or whether later introduction of fasting can make a difference to health-related outcomes and ageing. Well, the news is also good on this front. In animals, fasting introduced at any stage in adult life shows all of the cellular benefits detailed above, even in very old animals. Humans gain benefits from fasting, no matter what age it is introduced in adult life, but the earlier one starts, the longer and more dramatic the outcomes. Try it: I’ve only been doing it for three years and I can honestly say I now enjoy it and I strongly encourage my patients to consider intermittent fasts. Whereas increasing lifespan and improving health in old age is enormously attractive to most people, a lifetime commitment to a reduced calorie diet is unlikely to be adopted at a population level. As a result, caloric restriction ‘mimics’ are being sought – in other words, drugs or supplements which have the same effects on cells as fasting. Several have already been identified, such as resveratrol, quercetin, fisetin, metformin and rapamycin.

Chapter 9: Eat to Your Heart’s Content

Resveratrol is part of a group of compounds called polyphenols, which act like antioxidants. Resveratrol extends lifespan in several species and occurs naturally in various plants, including red grapes, peanuts, prunes, blueberries and cranberries. You will probably be most familiar with references to resveratrol in red wine – which comes from the skin of grapes. Several laboratory studies have demonstrated beneficial immune protection via the action of resveratrol on the SIRT1 gene in animals and human cells. This gene is believed to protect the body against the effects of obesity and some of the diseases of ageing. So far, studies have not discovered any severe side effects, even when resveratrol is taken in large doses – though patients who are also taking blood thinners or clot reducing medications are advised to take care with intake. The dosages in most resveratrol supplements are typically lower than the amounts that have been seen to be beneficial in research. To get the dose used in research studies, consumption of up to 2,000mg of resveratrol a day is recommended. Red wine has only 5mg to 15mg in one litre. So, although wine has benefits, I am not recommending that you drink the equivalent of 2,000mg resveratrol in red wine per day – it’s best to source it from elsewhere!

Quercetin is another polyphenol found in fruit, particularly strawberries, nuts and herbs. It has anti-inflammatory properties, some antihistamine properties (anti-allergies) and increases anti-oxidant protection.

A new kid on the block as a fasting mimic is fisetin, which manipulates mTOR. This protein instructs insulin pathways and maintains good function of liver, muscle, white and brown fat tissue, and the brain. It appears to be very important for cell ageing. mTOR malfunctions in diabetes, obesity, depression, certain cancers and ageing cells. The relative proportions of fisetin in fruits and vegetables are strawberries (160), apples (27), persimmons (11), lotus root (6), onions (5), grapes (4) and kiwi (2). In other words, strawberries have eighty times more fisetin than kiwis. But human research on fisetin as a supplement is still in the early stages.

Chapter 9: Eat to Your Heart’s Content

Rapamycin is another mTOR inhibitor and a good candidate to mimic the effects of caloric restriction. This drug may have benefits for immunity in old age as well as broader positive health effects. It is already used to complement chemotherapy drug treatments in cancer patients but clinical trials proving efficiency and safety for ageing are as yet lacking. The action of metformin, a treatment for type 2 diabetes, also mimics caloric restriction and extends lifespan and health span in several species including rodents. Death rates are lower in diabetics taking metformin than those on other diabetic medications. This has generated a lot of interest in the drug’s potential for slowing ageing. With regard to immunity, recent clinical studies have reported an anti-inflammatory role for metformin and a beneficial effect for pathways involved in mouse models of arthritis. What can we conclude from what we have learned so far about these calorie restricting agents from early trials? Some of them are part of a healthy diet and taken as supplements may be beneficial and are unlikely to do harm. Others, such as rapamycin and metformin, need more clinical trials to establish benefits but are looking very promising – watch this space. If you want to live to be a happy 100-year-old, it’s worth looking to Japan, which is the country with the longest average life expectancy in the world, at an average of 87.3 years for women and 81.3 years for men. The average lifespan of the Japanese is the highest it has ever been and is increasing. In 2019, the number of Japanese aged 90 reached 2.31 million, which included over 71,000 centenarians. So, have the Japanese found the fountain of youth? Let’s delve into Japan’s dietary secrets for good health and longevity.

The diet is generally lean and balanced. Staple foodstuffs include omega-rich fish, rice, whole grains, tofu, soy, miso, seaweed and vegetables, all of which are low in saturated fats and sugars and rich in vitamins and minerals that reduce the risk of cancers and heart disease. This healthy diet has led to an impressively low obesity rate, while other countries are increasingly struggling. Just 4.3 per cent of the Japanese population is obese, compared to 27.8 per cent in the United Kingdom and a staggering 36.2 per cent in the United States. Obesity is a major cause of killer diseases like diabetes, cancer and heart disease, so it goes without saying that one reason that the Japanese live longer is likely to be their diet.

Chapter 9: Eat to Your Heart’s Content

The science backs it up. According to a study published in British Medical Journal, those who followed the Japanese government’s recommended dietary regime had a 15 per cent lower death rate than those who didn’t. And they start young. Japanese schools follow healthy dietary guidelines, with lunches of plenty of fruits and vegetables and very little refined sugar. Learning how to eat a balanced diet from a young age sets children up for good health for the rest of their (likely long!) lives. Something else that is taught from youth is a Confucian teaching: hara hachi bun me, which roughly translates to ‘eat until you are eight parts full’ – similar to the Blue Zones practice. It usually takes at least 20 minutes for the brain to recognise that we are full. Smaller portions and slower eating contribute to the long lifespan of the Japanese. At mealtimes, they serve the food onto lots of small plates, sitting on the floor and eating together. Along with using chopsticks, this slows down the whole eating process, which aids digestion. The Japanese have been drinking matcha green tea for centuries – the practice of traditional Japanese tea ceremonies that dates back over 1,000 years emphasises the important role it plays in their culture. This ancient drink is rich in antioxidants that boost the immune system and help prevent cancer, plus it even helps to preserve cell membranes, all of which combines to slow cell ageing. It also helps with digestion, energy levels and regulation of blood pressure. The secret to matcha tea’s powers is in the production process. The young leaves are deprived of sunlight when growing, which increases their chlorophyll and antioxidant content. The Japanese drink this tea several times a day. Next time you reach for a cup of coffee, why not try green tea instead? Aside from diet, other characteristics may also contribute to Japanese longevity. Around 98 per cent of Japanese children walk or cycle to school, while national radio stations broadcast ‘gymnastics’ each morning. The daily commute is also active, with most people walking or cycling to the train station, standing on the train, then walking to work. And it’s not that they don’t sit down – they just do it in a healthier way. People often sit on the floor for meals or socialising in a kneeling position known as seiza. The position involves resting on your shins and tucking your feet underneath your bottom. This helps to maintain strength and flexibility. Even going to the bathroom incorporates movement in Japan. Traditional Japanese toilets involve squatting, which is healthier for the bowels and muscles!