Rectal cancer is being diagnosed in younger and younger age groups, with trends suggesting that one in four to five rectal cancer patients will be under 50 within five years, which is why a healthy diet, regular exercise and enough sleep are essential. The gut microbiome, the collection of micro-organisms that live in our gut, is as unique as our fingerprints: each person has a different microbiome and the composition of the micro-organisms in our gut is as diverse as the different stages of our intestinal tract. We can improve our gut health by getting enough sleep and exercise, as well as adequate nutrient consumption, and even by occasionally reducing calorie intake, intermittent fasting or temporary fasting.

The physiological background of fasting – the so-called autophagy mechanism – has been further highlighted by research in recent decades. This Greek word means self-digestion, i.e. when our cells break down cellular components that are no longer functioning properly and reuse them or produce energy from them,” explains Dr. Katalin Leiszter.

A major breakthrough in the physiological background of the cell renewal process background of the cell renewal process was due to the research on autophagy by a Japanese cell biologist, Osumi Josinori, who was awarded the Nobel Prize in Medical Sciences in 2016.

According to the Adjunct Professor at the Department of Surgery, Transplantation and Gastroenterology of Semmelweis University, fasting may be linked to the production of certain hormones, such as glucagon, which is released during fasting, and other hormones that may stimulate autophagy, i.e. promote cell renewal.

“As doctors, we often see – not only for religious reasons during the period before Easter, but also regardless of this – that patients go on some kind of fasting or diet for a while in order to lose weight or change their lifestyle, or to get in shape for the summer, for example,” says the gastroenterologist.

There are many types of fasting, but one of the most common and perhaps easiest to do in everyday life is the so-called 16/8 period fast. These shorter fasts are not necessarily about what you eat, but when. In 16/8 fasting, you fast for 16 hours of the 24 hours of the day, and for the remaining 8 hours – from late morning to early evening – you can eat, so that during 16 hours, hormonal changes allow cell renewal, or autophagy, to work more efficiently. There are also variations of this, such as the 14/10 or 18/6 split, but there is also a type of fasting where you eat as usual five days a week, and on two days – preferably not two consecutive days – you eat a minimum of 500-600 kilocalories,” she says.

Dr. Katalin Leiszter also points out that the benefits of intermittent fasting and its disease-preventive role is the subject of current research, as is whether it is more effective than a long-term diet with reduced calorie intake.

What we know so far about these types of fasting is that they can contribute to weight loss, reduce certain blood fats and inflammatory factors, or improve insulin sensitivity in overweight patients

– she explains.

She also adds that fasting is not for everyone, for example it is not recommended for pregnant and breastfeeding mothers, children, and in case of many underlying conditions such as cardiovascular, metabolic, and gynaecological diseases, cancer, infertility, malnutrition, eating disorders, a doctor should be consulted before embarking on fasting. It should also be kept in mind that during a fasting period, the increased hunger may make people more tense and temporarily reduce their physical or mental performance, so it is best to schedule fasting days on less active days, such as weekends.

As the gastroenterologist points out, eating the right quantity and quality of fruit and vegetables, fibre and fluids (especially clean water) can improve the condition (integrity) of the intestinal mucosa, the composition and diversity of the gut microbiome and speed up transit time of the intestine, i.e. the time food stays in the intestinal tract. Altogether, these factors can reduce the risk of developing cancers, including colon cancer. This is because, among other things, a shorter time in the gut for potentially carcinogenic substances means less damage to the intestinal lining, and with adequate fibre intake, short-chain fatty acids are produced that can also contribute to the health of the intestinal lining. This is particularly important since it is predicted that by 2030, one in four to five rectal cancer patients will be in the under-50 age group.

March is the month of colonoscopy, and the prevention of colon cancer. While some risk factors for cancer (e.g. genetic predisposition, family history) are beyond our current knowledge, there are many modifiable risk factors that we can actively reduce. Being overweight or obese increases the risk of developing not only colorectal cancer but also many other cancers, such as smoking, physical inactivity and unhealthy eating. Evidence suggests that a Western-style diet, including high-fat, ultra-processed, low-fibre foods, high consumption of red meat and low fluid intake, may contribute to the development of colorectal cancer.

Orsolya Dávid
Translation: Viktória Kiss
Featured photo:; photo: Bálint Barta – Semmelweis University