The conclusions of two studies published in 2011, in the journal Cancer, suggest that the use of a fish oil supplement taken during treatment for cancer can help patients maintain their weight (**and improves the efficacy of chemotherapy**)
The first study examined the use of a fish oil supplement (2.5 grams of EPA + DHA/day) in patients undergoing first-line chemotherapy for non-small cell lung cancer. The control group of patients only received chemotherapy. The authors found at one year:
- A significant improvement in the response rate to the chemotherapy in those patients that received the fish oil supplement versus the chemotherapy-only group (60.0% vs 25.8%, P = .008).
- Although not statistically significant, the one-year survival was higher in the fish oil group versus the control group (60.0% vs 38.7%; P = .15). (**Clearly this finding needs to be further assessed in larger, more robust trials to confirm this promising result**)
The second study examined the potential of a fish oil supplement (2.2 grams of EPA/day) to help maintain weight in patients undergoing chemotherapy for non-small cell lung cancer. The control group of patients again only received chemotherapy (no fish oil supplements). The authors reported:
- Patients in the control group (no fish oil supplements) lost an average of 2.3 ± 0.9 kg.
- Patients receiving the fish oil supplement maintained their weight (0.5 ± 1.0 kg) (P = .05)
- 69% of patients in the fish oil group gained or maintained muscle mass (only 29% of patients in the control group maintained muscle mass, and overall the SOC group lost 1 kg of muscle.)
- There was no difference in total adipose tissue was observed between the 2 groups
The fish oil supplements used in these experiments contained the omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). You can purchase them at most pharmacies, grocery and supplement stores.
The pharmaceutical industry (Glaxo Smith Kline) has climbed onto the omega-3 fatty acid bandwagon with a product called, Lovaza. This is nothing more than than an expensive version of EPA and DHA. Save your money. There is nothing different about this product than the non-prescription versions.
If supplements are not your thing, you can obtain EPA and DHA from consuming cold water oily fish. The fish with the highest concentration of these fatty acids are: salmon, herring, mackerel, anchovies, sardines and tuna. Krill (a shrimp-like marine crustaceans) is also an excellent source of EPA and DHA, and many supplement manufacturers tout krill as a healthier source of omega-3 fatty acids due to their very low levels of mercury and other toxic contaminants.
Plant sources of omega-3 fatty acids (i.e. ALA or α-linolenic acid) may not have as beneficial effects as those from fish oils (ALA is converted to EPA and DHA in the body, but with a low efficiency).
As an oncologist, I am very aware that some of our therapies can lead to substantial weight loss in our patients. Consuming EPA/DHA omega-3 fatty acids (through dietary sources, fish oil or EPA/DHA supplements) may help patients maintain their weight during treatment.
For the appropriate patients, I recommend that they start taking 2000-2500 mg of EPA/DHA per day to help them maintain their weight. If you are considering taking these (or any new supplement), first discuss this with your oncology team as there are potentially serious side-effects, complications and medication interactions that can occur.