Following is a brief overview of calorie restriction: the promising avenues of research, how you can put it into practice and the substances that replicate its effects.
Let’s first restate that this intervention consists of reducing one’s daily food intake - by at least 15% and necessarily accompanying it with appropriate supplementation to avoid any risk of deficiencies.
The effects of calorie restriction were observed as far back as the sixteenth century. It was the aristocrat Luigi Cornaro who first wrote about it in his book ‘Discourses on the Sober Life’. Finding himself in failing health due to his decadent lifestyle, he decided to adopt an almost ascetic diet. Cornaro attributes this move with significantly prolonging his life - he actually survived until the age of 98 (1). The scientific community was slow to take an interest in the processes involved, but has now ended up concurring with the aristocrat’s view.
Studies on animals, particularly rodents and primates, have shown that calorie restriction activates the genessirtuins.
These have multiple effects in the body:
Sirtuins thus act at several levels to curb premature ageing, slowing down metabolism and protecting functions essential for life. (2)
In addition, calorie restriction may make the body more sensitive to insulin, reducing diabetes, and may encourage the body to burn stored fat. It therefore seems to play a role in protecting both the cardiovascular and nervous systems. And finally, scientists have shown calorie restriction and the mechanisms involved to be highly promising avenues of research in the fight against cancer development. (3)
In terms of human instances, we can look at the example of the inhabitants of Okinawa, in Japan. These people are proponents of a restricted diet and their exceptionally long life expectancy is particularly encouraging. Calorie restriction can also take the form of intermittent fasting. This is a gentler way of reducing food intake and is also proven to produce weight loss.
To practice intermittent fasting, you need to abstain from eating for 16 hours. The best time for many people is the interval between (an early) dinner and lunch the next day, skipping breakfast. It’s also possible to go without dinner or lunch, depending on your personal eating patterns and preferences. You can also try other ways of fasting, such as the 5:2 diet. This involves reducing your food intake by 25% for two days each week, and eating normally on the other five days .
Studies are starting to show that intermittent fasting may have comparable effects to those of calorie restriction, especially in terms of sirtuins (4). When practised correctly, these methods are safe and make it possible to take the first steps towards calorie restriction.
Calorie restriction can be seriously restrictive, both on a day-to-day basis and over the long term. The good news is that scientific advances have led to the identification of certain molecules that mimic its effects! (5) They include:
Calorie restriction and the molecules that aim to reproduce its effects represent promising options for extending longevity to the max!