The medical aspects of fasting-mimicking diets

By: Hanno Pijl
internist-endocrinologist and professor of Diabetology at the Leiden University Medical Center

Why is fasting good for us?

We all eat too much in the Netherlands. Every day at least 3 times and almost everyone eats snacks in between. This is not what we were made for. Only since the industrial revolution, a few hundred years ago, we have the availability to three meals a day. Before that, we regularly had to survive longer periods without food. Our bodies have adapted to that, our cells “feel” when there is less food comes into our body and adapt to that. The body becomes more energy efficient, cells stop growing and multiplying, and invest more in maintenance and repair. They protect themselves from damage and start using waste products in the cell as fuel (also called “autophagy”). They “clean themselves up”. All of this is meant to survive the period of food scarcity.

Therefore, occasional fasting is good for us. Animal studies have shown that intermittent fasting greatly reduces the risk of diseases such as diabetes, cardiovascular disease, cancer and autoimmune diseases and extends life. It is difficult to demonstrate this in humans, because it requires lengthy and large-scale research. However, the direct biological effects of fasting in humans are exactly the same as in animals: blood pressure and metabolism are greatly improved, inflammation is quickly dampened and cell damage is reduced. It is therefore accepted that regular fasting also reduces the risk of disease in humans.

Fasting through the regular way is quite difficult, especially if you are not forced to do it. Humans have a natural urge to eat, especially when food is within reach. Research has shown that our cells react strongly to a shortage of protein (=building material) and sugar (=fuel). That knowledge gave top scientist Valter Longo the idea of ​​a “fast-mimicking diet”: food that contains virtually no sugar and protein, but does contain fiber and healthy fats, so that your body thinks that nothing is entering (no sugar and protein), but you are still able to eat something. A lot of research has since shown that fasting-mimicking diets have the same effects as total fasting. L-Nutra is an American Nutri-Tech company that makes fasting mimicking diets (FMD). L-Nutra was founded by Valter Longo and the University of Southern California, where he works.

The use of fasting-mimicking diets

FMDs are formulated in such a way that the body reacts as if nothing was eaten at all. There is a growing body of research showing that regular use of an FMD can contribute to better health. It is also very safe to use for healthy people. You may notice that your energy levels go down during the 5 days of FMD, and sometimes you might even feel dizzy when standing (because your blood pressure drops). If you are ill, it is wise to consult your doctor first. Sometimes it is unwise to lose (even more) weight. Sometimes the use of medicines also needs to be adjusted (such as medicines for diabetes or high blood pressure). Consult your doctor first if you are hesitating.