A recent study has suggested that patients undergoing chemotherapy should intake fish oil as it could help them in maintaining weight. Supplements of fish oil could also prevent the damage of healthy fat tissues that results from chemotherapy.

Chemotherapy can cause loss of weight or muscles and patients become weak and malnutrition after the treatment but fish oil prevents such loses by interfering with the pathways that are altered in advanced cancer. The weight loss occurs due to patients' inability to digest and absorb the nutrients of food. Fish oil is a rich source of Omega3 Fatty Acid that can enhance the growth of muscles during the treatment.

A study was conducted by Vera Mazurak, PhD, of the University of Alberta in Edmonton, Canada, to examine the effect of fish oil on patients undergoing chemotherapy. 16 patients were given regular supplements of fish oil where as 24 patients were not given any such supplements. These patients were under chemotherapy for 10 weeks and their body weights were checked regularly. After 10 weeks the reports revealed that patients, who did not take fish oil, lost an average of 2.3 kilograms while the patients who were taking fish oil supplements maintained their weight.