Effects of a ketogenic diet on the quality of life in 16 patients with advanced cancer: A pilot trial

Tumor patients exhibit an increased peripheral demand of fatty acids and protein. Contrarily, tumors
utilize glucose as their main source of energy supply. Thus, a diet supplying the cancer patient with sufficient fat
and protein for his demands while restricting the carbohydrates (CHO) tumors thrive on, could be a helpful
strategy in improving the patients
situation. A ketogenic diet (KD) fulfills these requirements. Therefore, we
performed a pilot study to investigate the feasibility of a KD and its influence on the quality of life of patients with
advanced metastatic tumors.
Sixteen patients with advanced metastatic tumors and no conventional therapeutic options participated
in the study. The patients were instructed to follow a KD (less than 70 g CHO per day) with normal groceries and
were provided with a supply of food additives to mix a protein/fat shake to simplify the 3-month intervention
period. Quality of life [assessed by EORTC QLQ-C30 (version 2)], serum and general health parameters were
determined at baseline, after every two weeks of follow-up, or after drop out. The effect of dietary change on
metabolism was monitored daily by measuring urinary ketone bodies.
One patient did not tolerate the diet and dropped out within 3 days. Among those who tolerated the
diet, two patients died early, one stopped after 2 weeks due to personal reasons, one felt unable to stick to the
diet after 4 weeks, one stopped after 6 and two stopped after 7 and 8 weeks due to progress of the disease, one
had to discontinue after 6 weeks to resume chemotherapy and five completed the 3 month intervention period.
These five and the one who resumed chemotherapy after 6 weeks report an improved emotional functioning and
less insomnia, while several other parameters of quality of life remained stable or worsened, reflecting their very
advanced disease. Except for temporary constipation and fatigue, we found no severe adverse side effects,
especially no changes in cholesterol or blood lipids.
These pilot data suggest that a KD is suitable for even advanced cancer patients. It has no severe
side effects and might improve aspects of quality of life and blood parameters in some patients with advanced
metastatic tumors.