Many patients believe that they can “starve” the tumor by means of special diets or fasting cures. Internet information strengthens their belief. But what is the scientific truth of such practices?
The so-called therapeutic fasting, the ketogenic diet, and other similar nutritional methods are supposed to support patients in their fight against tumors, by means of “starving” the tumor cells and thus support a treatment. The concept of nutrient removal does not actually sound that wrong. The rationale behind this approach is that if you take away the fuel from the tumor, i.e. sugar, it will die. But is it really that simple? and what do the studies say?
At this year's German Cancer Congress (DKK) in Berlin, the topic of diet and cancer was, among other things, part of the Science Slam titled "Integrative Oncology: Facts against Myths" which took place on February 20th, 2020. Attendance was very high even as the event itself was not open to all congress attendants. This showed how exciting questions about nutrition and phytomedicine are at present. Speakers were mostly young physicians at the beginning of their careers, who without exception presented fresh and entertaining lectures and nevertheless approached the topics of the day in an evidence-based and comprehensive manner.
Although many people may have an opinion about the ketogenic diet, and plenty of internet sites seem to be pouring out information on the topic, there are hardly any reliable studies that can provide extensive conclusions. Much is based solely on in-vitro studies and mouse models, so the 1:1 transferability to humans is questionable.
However, it is a fact that such diets change the body and its functions in humans. Cancer cells literally crave for sugar. Diminishing this energy source to them is the basis of ketogenic diets.
In contrast to chronic hypocaloric fasting, (which is supposed to starve cancer out, but risks malnutrition that worsens the prognosis and increases the risk of mortality), in the ketogenic diet, the sugar is replaced isocalorically by other macronutrients such as fats or proteins. Glucose uptake decreases and is also supposed to eventually deprive the tumor of sugar. This leads to a decrease in growth-promoting factors such as IGF-1 and to a lack of energy in the tumor cells. According to the theory derived from the models, autophagy processes are triggered in the degenerated cells and CD8-positive T-lymphocytes of the immune system are additionally activated in the entire body. However, these connections have not yet been proven in humans.
Source: Science Slam "Integrative Oncology - Facts versus Myths"; DKK 2020; Berlin, 20.02.2020