Omega-3 fatty acids and cancer
Omega-3 fatty acids are essential polyunsaturated fats found in sources like cold-water fish, flaxseeds, walnuts, and certain oils. They are known for their potential role in health, particularly regarding inflammation and cell division, which may relate to cancer prevention. Research has explored the relationship between omega-3 fatty acids and various cancers, including colon, breast, prostate, and pancreatic cancer. While some studies suggest that omega-3s, particularly eicosapentaenoic acid (EPA), may help reduce the risk of certain types of cancer by mitigating inflammation, other research indicates potential adverse effects on cancer treatment and an increased risk for specific cancers, such as skin and lung cancer.
The balance between omega-3 and omega-6 fatty acids is crucial, as omega-6s can promote inflammation, which contributes to tumor growth. Side effects from omega-3 supplementation may include gastrointestinal issues and a taste alteration. Additionally, individuals on blood thinners or certain medications should exercise caution when consuming omega-3s. Overall, while omega-3 fatty acids show promise in cancer-related research, the findings are mixed and highlight the need for further investigation to understand their role fully.
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Subject Terms
Omega-3 fatty acids and cancer
ALSO KNOWN AS: Polyunsaturated fatty acids (PUFAs), omega-3, Omegaven injectable emulsion (ILE)
DEFINITION: Omega-3 fatty acids are essential polyunsaturated fats that come from cold-water fish, fish oil, flaxseeds, soybeans, walnuts, linseed oil, chia seeds, green leafy vegetables, and canola oil. The three forms of omega-3 fatty acids include alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).
Cancers treated or prevented: Colon cancer, breast cancer, prostate cancer, pancreatic cancer
Delivery routes: Oral by food, capsule, or liquid
How this substance works: Omega-3 fatty acids are highly concentrated in the brain and appear to play an important role in cognitive and behavioral functions, as well as normal growth and development. Research indicates that these acids are important in numerous physiological functions, particularly muscle contraction and relaxation, movement of calcium and other material into and out of cells, regulation of blood clotting, and secretion of substances, including hormones and digestive enzymes. They also play a role in controlling cell division and fertility, indicating their possible importance in protection against certain types of cancer. Omega-3 fatty acids reduce inflammation and stunt tumor growth. In contrast, omega-6 fatty acids in sunflower, safflower, and most saturated fats and vegetable oils promote inflammation and feed tumor growth. An appropriate balance between omega-3 and omega-6 fatty acids is necessary to promote good health.
Research concerning omega-3 fatty acids and cancer is mixed and inconclusive. Some research indicates that omega-3 fatty acids help to prevent certain chronic diseases, including heart disease and some cancers. EPA appears to be important in cancer prevention by affecting the production of cytokines and the tumor necrosis factor (TNF). Other research indicates that omega-3 fatty acids may play an adverse role in treating some cancers. If the latter is true, these acids still play an indirect role in cancer prevention if cold-water fish, such as salmon, halibut, and tuna, are substituted for red and processed meats, which are known to increase the risk of colon and prostate cancers.
Side effects: Common side effects of using omega-3 may include diarrhea, nausea, or a foul taste in the mouth. The consumption of omega-3 fatty acids and cancer incidence have had unfavorable associations in some case studies. One study on skin cancer and another on lung cancer showed that these fatty acids increased the risk of developing these cancers. A prostate cancer study showed that ALA increased its risk, while EPA and DHA reduced the risk. Another study found that prostate cancer, especially aggressive prostate cancer, was associated with higher intakes of oily fish and fish oil supplements. More specific case studies must be conducted to build a significant statistical database.
Omega-3 fatty acids should be avoided by those who take blood thinners—aspirin, heparin, warfarin, clopidogrel, apixaban, or rivaroxaban. Similarly, individuals taking glucocorticoids—cortisone, hydrocortisone, or dexamethasone—should avoid omega-3 fatty acid supplements. In patients with clear cell renal cancer, taking omega-3 fatty acids with Pazopanib can cause stomatitis and oral mucositis.
Bibliography
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