The Roles of Lipids in the Most Recent History of Cancer Prevention

Emerging science on lipids

Despite the significant bank of research that has been built up on the subject of cancer pathology, mortality rates remain high. It is estimated that worldwide 8.8 million people died from cancer in 2015.² Given that risk factors grow with age, this number looks set to rise even further with the increasingly elderly population. The disease continues to place a huge economic burden on global healthcare systems; in 2010, the annual cost of cancer was estimated at US$1.16 trillion.

The latest scientific research shows that lipids EPA and DHA have emerging potential alongside current treatments. In fact, studies indicate that they could have a cytotoxic effect, while providing simultaneous protection of healthy cells from oxidative stress-induced apoptosis and other damage.³ In clinical settings for cancer patients, EPA and DHA have been reported to improve immune response, help individuals maintain lean body mass and prevent cachexia, as well as increase quality of life.^4,5 Studies have also found that EPA and DHA could improve overall survival in patients with gastrointestinal (GI) cancers, specifically colorectal, esophageal and pancreatic, as well as breast cancer.⁶

Reducing the risk

EPA and DHA are well known for their anti-inflammatory activity across a number of pathways and recent research has also shown that the ingredients could help to shape biological membranes to reduce the risk of cancer.⁷

For example, a study published in Gut demonstrated that EPA has chemopreventative efficacy in patients with familial adenomatous polyposis. The randomized, double-blind, placebo controlled trial gave patients either 2g or a placebo daily for six months, and the size and number of polyps were recorded before and after the treatment. Those who had received EPA had a mean 22.4% reduction in polyp number and a 29.8% decrease in the sum of polyp diameter. In comparison, the placebo group showed a worsening in the global polyp burden over six months. Although further studies are needed on a larger cohort, this research highlighted the potential of EPA in suppressing polyp formation.⁸

Studies on breast cancer

Meanwhile, breast cancer is the most frequently diagnosed cancer in women, and the second leading cause of cancer death in females.⁹ There remains a high mortality rate, as breast cancer pathology is complex and strongly heterogeneric. Although significant advances have been made in screening, diagnosis and management, survival rates depend on availability of early detection programmes, access to diagnostic and treatment facilities, the type of cancer and long-term complication of treatment.

However, a number of population health and animal studies suggest that high intake of fatty fish (a source of EPA and DHA) could lower the risk of breast cancer. A recent meta-analysis and systemic review of 21 prospective cohort studies reported that the risk of breast cancer decreases by 5% for every 100mg increase intake of long chain polyunsaturated fatty acids.¹⁰

There is also increasing evidence to suggest EPA and DHA may improve chemotherapy efficacy, thanks to their anti-carcinogenic properties in mammary cancers, both in vivo and in vitro. One particular report assessed cell growth when incubated with EPA and DHA, either with or without chemotherapy agents, such as doxorubicin (dox) or Herceptin. Pre-treating estrogen receptor negative cells with DHA was found to increase the anti-cancer effects of dox.¹¹

Furthering lipid research

While more studies are needed to determine the extent of the benefits of lipids, such as EPA and DHA, in the modulation of cancer risk, initial research looks promising. As such, there is an opportunity to develop prevention and therapeutic strategies that incorporate such interventions.

Future research should focus on advancing clinical studies, to further explore how EPA and DHA could be used together with conventional cancer treatments.