It's likely many of you have heard reports regarding the Omega-3s and Prostate Cancer Study. I want to share with you my takeaway:
- This study was not specifically designed to look at the exact relationship between omega-3 fatty acid intake and prostate cancer.
- If the findings were true, then prostate cancer would be rampant in any country with high seafood consumption (Scandinavia, Japan, etc) and conversely, low-level consumption should be protective. Clearly this is not the case.
- Plasma phospholipid fatty acids as measured in this study are not a good index of long term intake and are influenced dramatically by a single meal, or even timing of a fish oil dose. A single fish oil dose massively increases LC omega 3 (typically increasing levels by 100% or more) in about 4-12 hours and then washes out around 48 hours.
What else should you know?
- A recent meta-analysis of fish consumption and prostate cancer by Szymanski et al. (2010) reported a large reduction in late stage or fatal prostate cancer among cohort studies.
- Several population based studies have shown a benefit of increased omega-3 fatty acid intakes to reducing prostate cancer risk (Lietzman et al., 2004, Terry et al., 2001).
- A recent meta-analysis by Zheng (2013) of 16 independent cohort studies reported the association between marine n-3 PUFA (reported as intake or biomarker data) and risk of breast cancer, involving 16,178 breast cancer events and 527,392 participants. Marine n-3 PUFA was significantly inversely associated with risk (relative risk 0.86, 95% confidence interval 0.78 to 0.94). Dose-response analysis indicated that a 0.1g/day increment of dietary marine n-3 PUFA was associated with 5% lower risk of breast cancer.