Traditionally, the ketogenic diet has been used as an adjunct treatment to control seizures. However, as more oncology patients, researchers, and professionals question the relationship between cancer and sugar, the potential therapeutic benefit of the ketogenetic diet in oncology has become the topic of increasing research and debate. The scientific community is now learning about the diet’s possible tumor inhibiting effects although significantly more research is required before we fully understand the complex effects.
What is the ketogenic diet, and how does it work?
The ketogenic diet is high in fat and low in protein and carbohydrates. In some respects, the ketogenic diet is similar to the Atkins diet although it is more stringent in terms of protein consumption.
Under “regular” eating patterns, the body breaks down carbohydrates into glucose for energy. However during times of fasting, or when there is insufficient carbohydrate and protein intake, the body uses fat as its energy source. During the breakdown of fat, ketones – a byproduct of fat metabolism – are used as the source of energy. Since the ketogenic diet limits protein and carbohydrate consumption, a person on the diet gets his or her energy primarily from ketones.
How do ketogenic diets relate to oncology?
Healthy cells in the body can obtain energy from both glucose and ketones. However, a theory called the Warburg Effect explains that cancer cells cannot make use of ketones. Thus, it is hypothesized that if ketones are available but not glucose, healthy cells survive, while other abnormal cells may not.
Current Research: One size does not fit all
Cancer is an umbrella term for abnormal cells, and not all abnormal cells behave in the same manner. Thus, it is not surprising that different cancer cells respond differently to the ketogenic diet.
Research studying the impact of a ketogenic diet on each specific cancer diagnosis remains preliminary and inconclusive. Currently, it seems that the ketogenic diet may be beneficial for certain aggressive brain tumors like glioblastomas due to the unique nature of energy utilization in the brain. On the contrary, experimental models indicate that the ketogenic diet may actually have detrimental impacts for other conditions like breast cancer.
Considerations with the ketogenic diet
Due to its highly restrictive nature, there are other side effects that must be taken into account for people who decide to follow the ketogenic diet. The diet’s low carbohydrate and protein content may cause constipation in some individuals. Some research subjects also report increased fatigue. Diabetic patients in particular may experience a higher incidence of hypoglycemia. In addition, this diet is not recommended for people prone to developing kidney stones or with compromised renal function.
The bottom line is that it is essential for people on or considering the ketogenic diet be evaluated by trained medical professionals to monitor for both physical and biochemical changes as well as to prescribe supplements like calcium and vitamin D as necessary. The ketogenic diet is extremely restrictive and requires a specific ratio of macronutrients to be effective. It necessitates a highly motivated, disciplined and capable patient to continue the diet for any length of time. Quality of life should also be considered since food choices are severely limited on the diet.
Future Directions
At present, the less than thorough state of the research about the ketogenic diet leaves medical professionals with a hazy idea about its appropriate application and practical implementation. Over the next decade, further research hopefully will reveal more about the diet and whether other similar diets such as Atkins provides any similar therapeutic benefits to populations who might benefit from the ketogenic diet. Since the Atkins diet allows for a more liberal choice of foods, this would have significant impact on quality of life. Going forward, further research will shed additional light on the appropriateness of ketogenic diets for specific sub-populations.
References
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