While omega-3 has been shown to have multiple health benefits, there has been no consensus on its efficacy on inflammatory and immune function in post-operative patients with gastrointestinal malignancy.
Based on this, researchers in China conducted a meta-analysis literature from RCTs, using PubMed, Embase, Scopus, Cochrane Library, CNKI, Weipu, and Wangfang as their points of reference.
They reviewed 16 RCTs involving 1,008 patients, then compared the immune efficacy outcomes in 506 gastrointestinal cancer patients receiving parenteral nutrition supplemented with omega-3 emulsion against outcomes in the 502 patients in placebo groups.
They then reported that after supplementation, the proportions of immune system cells in the treatment groups were significantly higher than those in the control groups.
In addition, levels of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α) and C-reactive protein in the treatment groups were found to be significantly lower than in the control groups. The former's immunoglobin levels and lymphocyte count were also markedly higher than those in the control groups.
However, the researchers also stated that the meta analysis had a major limitation: all the RCTs were Chinese studies, meaning the results were unlikely to be generalisable to other ethnic populations.
At the same time, "experience and methods of perioperative management used at different hospitals and specialist centres could have produced different outcomes and increased the heterogeneity among the included studies".
Positive indications, future considerations
The researchers wrote that early intervention with omega-3 emulsion could improve post-operative immune function indicators and reduce inflammatory reaction.
They concluded: "Omega-3 fatty acids play an important role in the regulation of inflammatory factors and immune function, and improve the nutritional status through a variety of mechanisms.
"The result of this meta-analysis confirmed that early intervention with ω-3 fatty acid emulsion in gastrointestinal cancer can not only improve the postoperative indicators of immune function, reduce inflammatory reaction, and improve the postoperative curative effect, but also improve the immune suppression induced by conventional parenteral nutrition or tumours.
"Therefore, post-operative patients with gastrointestinal cancer should add ω-3 unsaturated fatty acids in their parenteral nutrition formula. Further high-quality RCTs are needed to verify its efficacy."
"Effect of ω-3 polyunsaturated fatty acid-supplemented parenteral nutrition on inflammatory and immune function in postoperative patients with gastrointestinal malignancy: A meta-analysis of randomized control trials in China"
Authors: Yajie Zhao, Chengfeng Wang