Low carbohydrate diet protects women with breast cancer during chemotherapy
When women with advanced breast cancer are treated with chemotherapy, their chances of survival increase when they switch to a ketogenic diet. At the same time, a low carb diet improves their body composition. Iranian researchers say this in a human study that appeared in Nutrition & Cancer.Study
The researchers experimented with 60 women aged 18-70, all of whom have advanced breast cancer. The researchers divided the women into two groups.

For 3 months during which the women received chemotherapy, the women in the control group ate 'normal'. 55 percent of the energy in their diet came from carbohydrates, 15 percent from protein and 30 percent from fat.The women in the experimental group ate ketogenic. The energy in their diet came for 6 percent from carbohydrates, 19 percent from protein, 55 percent from fat and 20 percent from supplements with MCTs. The researchers used a product from the Dutch company Nutricia. [nutriciamedischevoeding.nl]
Both groups lost body fat, perhaps as a result of the radiation. However, the fat loss was greater in the keto group. In that group, the women lost nearly 7 kilos of fat - but no fat-free mass.

The women in the keto group had fewer triglycerides and more of the 'good cholesterol' HDL in their blood than the women in the other group. On the other hand, the level of 'bad cholesterol' LDL was higher in the women in the keto group.
Perhaps more important are the chances of women surviving. When the three months were over, forty percent of the women in the control group had died. Of the women in the keto group, everyone was still alive at that time.

Side effects

The keto diet had no insurmountable side effects. The women did, however, find it difficult to adhere to a diet without "carbohydrate-containing foods such as fruits, milk, breads, rice, and sweets", and felt weak and hungry during the first few weeks of the experimental period.Conclusion
"A MCT-based ketogenic diet can [...] improve the biochemical parameters and body composition in favor of disease treatment in patients with locally advanced and metastatic breast cancer," the researchers summarize.

"A ketogenic diet can also improve the overall survival in neoadjuvant patients."
Nutr Cancer. 2020;72(4):627-34.