Author: Sandra Krstev Barać, mag.nutr.
The ketogenic diet, which basically means a high intake of fat and a low intake of carbohydrates and moderate protein, has been incredibly popular in recent years. It is attributed a positive effect on body mass, but also metabolic parameters such as blood glucose levels. Precisely because of the interesting metabolic effects on cells, the ketogenic diet does not cease to intrigue the oncology community. Oncology patients, moreover, are extremely keto-curious, all thanks to studies that have shown that its use can prevent the progression of malignant diseases.
However, before the patient embarks on such a restrictive diet, he must be aware of numerous facts. There is a lack of high-quality randomized clinical studies on this topic; a positive effect has been recorded in animal studies and reports of individual cases. Furthermore, the ketogenic diet makes sense only as a supportive therapy to standard oncological treatment and only in certain types of cancer.
The most evidence supports the use of a ketogenic diet in glioblastoma, an aggressive form of brain tumor, while the evidence for its usefulness in other types of malignant diseases is less.
Metabolic effect of ketogenic diet
Ketogenic diet, in the context of oncology, is based on the thesis that individual cancer cells depend exclusively on glucose as a source of energy and that due to mitochondrial dysfunction, they are unable to metabolize the ketone bodies that are produced. In this way, it is believed, cancer is "starved" and prevented from spreading. Following a ketogenic diet leads to a decrease in blood glucose levels, which reduces the level of insulin and insulin-like growth factor I (IGF-1), which are otherwise important drivers of the spread of malignant diseases.
But that's not all! Recent findings reveal that ketone bodies also promote oxidative stress in tumor cells, which makes them more sensitive to certain therapies such as radiation and chemotherapy. This explains the recorded cases in which the use of a ketogenic diet potentiated the positive effect of standard therapy. Therefore, the opinion today is that the ketogenic diet has its place in oncological treatment, but only as a support for standard therapy, and only for certain types of cancer such as brain tumors, and only with the support of a multidisciplinary team of experts.
A ketogenic diet is prescribed by an expert
Depending on the type of cancer and the prescribed therapy, a ketogenic diet can potentially help some cancer patients, but harm others. Therefore, it is important that the oncologist conducts a screening of patients in whom it is justified to try introducing a ketogenic diet. In doing so, the degree of the disease, the tolerance of the therapy itself, but also of the extremely high-fat diet are taken into account. If an oncology patient has diabetes, liver, kidney or heart disease and has had his gallbladder removed, he is not a candidate for the ketogenic diet.
The ketogenic diet is not standardized, but the nutritionist creates an individual diet plan adapted to the patient. The goal is to bring the patient into a state of ketosis, which is most often achieved in such a way that fats provide 80-90% of the total energy, but we are all different and do not achieve ketosis in the same way. That is why, in consultation with a nutritionist, it is preferable to use the strips available in the pharmacy to control the level of ketone bodies in the urine in order to know that the diet is having an effect. The next step is to calculate the ratio of glucose and ketone levels in the blood (glucose ketone index, GKI), which, it is believed, should be around 1 for the best "anticarcinogenic effect".
The importance of nutritional support
The ketogenic diet, in the context of cancer, is implemented in parallel with the introduction of oncology therapy, and its safety and effectiveness are monitored. In the first days of the diet, problems with constipation, bloating, dizziness, headache and nausea are possible, but they are temporary in nature. What you should pay attention to is unintentional weight loss, increased blood fat levels, and deficiencies of certain vitamins and minerals in order to react in a timely manner.
An additional challenge is to get the patient to adhere to the strict ketogenic diet regimen. Therefore, the role of nutritionists in implementing a diet for oncology patients is extremely important. In addition to providing support in planning and properly implementing the diet and taking care of the patient's nutritional status, the nutritionist has the important task of facilitating its implementation.
Conclusion
The ketogenic diet, or the ketosis achieved with it, shows potential in the treatment of malignant diseases (especially when it comes to brain tumors), but only in the case when it is used in parallel with standard therapy such as chemotherapy or radiation. Although some patients have the attitude that it is "only about the diet" and want to try their hand at implementing it independently, here the ketogenic diet has the role of supportive medical therapy, so it is extremely important to implement it in cooperation with experts and continuously monitor its safety and success.
References
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