In the ongoing quest to improve cancer treatment outcomes and patient well-being, a recent clinical trial has indicated that fish oil containing n-3 fatty acids could be an adjuvant in reducing the severity of adverse events related to chemotherapy in gastrointestinal cancer patients. The findings from this randomized, placebo-controlled, triple-blind clinical trial were published in the Clinical Nutrition ESPEN journal, providing a promising outlook for dietary interventions in cancer treatment protocols.

Clinical Trial Design and Outcomes

DOI: 10.1016/j.clnesp.2019.02.015

The pioneering study led by Carolina de Quadros Camargo and colleagues at the Federal University of Santa Catarina in Brazil aimed to investigate the effects of fish oil supplements on the treatment response and quality of life of patients undergoing chemotherapy for gastrointestinal cancers.

A total of 76 eligible patients were initially considered for the study. After the initial screening and randomization, 56 patients were enrolled in the trial, with 51 completing the full study. The participants were randomly assigned to two groups: the Fish Oil Group (FOG) and the Placebo Group (PG). Patients in the FOG received two capsules of fish oil daily, amounting to 1.55g of EPA and DHA, over a span of nine weeks. In contrast, the PG received two capsules of olive oil as a placebo.

Key Measures

1. Adverse events presence and grading
2. Performance status
3. Oxidative stress parameters in non-neoplastic cells
4. Tumor markers
5. Treatment response
6. Survival at one year

Notable Findings

The results demonstrated that although there were no significant differences between the two groups concerning overall treatment response or presence of adverse events, the severity of certain negative effects, particularly diarrhea, was notably lesser in the FOG compared to the PG (p = 0.03). Additionally, the FOG displayed a better performance status score, indicating a positive effect on the general health and activity levels of the patients (p = 0.02).

Importantly, the researchers did not observe any significant changes in lipid peroxidation and antioxidant enzyme activities between the groups, suggesting that the fish oil supplementation did not increase oxidative stress in the patients.

Implications and Future Directions

The trial’s outcomes suggest that supplementing with fish oil during chemotherapy may ameliorate some of the severe side effects that gastrointestinal cancer patients may experience, without worsening oxidative stress levels. This may lead to an improved quality of life and potentially enable patients to better continue with their treatment regimens.

According to Camargo and the research team, the findings justify further exploration of n-3 fatty acid supplementation as an adjunctive treatment in cancer care. Their study is registered under Identifier no. NCT02699047.


1. Camargo CQ, Mocellin MC, Brunetta HS, et al. Fish oil decreases the severity of treatment-related adverse events in gastrointestinal cancer patients undergoing chemotherapy: A randomized, placebo-controlled, triple-blind clinical trial. Clin Nutr ESPEN. 2019;31:61-70. doi: 10.1016/j.clnesp.2019.02.015.
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4. Gastrointestinal cancer treatment
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The study at hand presents valuable insights into how a simple dietary supplement could enhance the standard of care in chemotherapy. As the world continues to seek improvements in cancer therapy, interventions like fish oil supplementation could play a crucial role in refining treatment protocols and improving the overall experience for patients battling cancer. It is evident from this research that the power of omega-3 fatty acids extends beyond traditional nutrition, potentially offering solace and strength to those in the throes of cancer treatment.