Is The Link Between Fish Oil and Cancer Genuine?
As a big advocate of fish and fish oils I was surprised to see a research study all over the media recently saying – that omega 3 fatty acids (like the oil found in fish) can cause prostate cancer cadiahoangtuan.com in men.
I feel the need to respond and clear up any confusion.
Today we will look a little closer at this research as well as giving you an overview of the subject of fish oils.
The Study in Question
The study was carried out at a cancer research center in Seattle.
The study tested 834 males diagnosed with prostate cancer and aimed to find out if there was a relationship between cancer and omega 3 intake.
The study found that subjects with high levels of omega 3 fatty acids in their blood, had a 43% increased risk of prostate cancer overall and a 71% increased risk for aggressive prostate cancer. The study also suggests that eating high levels of linoleic acid (omega 6 fatty acids) were associated with a lower risk.
(Both these claims are a complete opposite of what my views as a nutritionist are, I recommend my clients eat plenty of fish (omega 3) or take a fish oil and not eat too much vegetable oils (omega 6).)
Blood samples from the men who had developed prostate cancer during the trial had more omega 3 fats than those who didn’t develop prostate cancer.
This really adds to the confusion.(I would say that its the aim of the government and some research – to cast doubt in your mind, to keep you confused, have you ever noticed how confusing health and fitness can be, people saying the complete opposite of each other all the time, like this article!)
I admit it can be hard to know what to do for the best.
Research is not the be all and end all, and it can prove or disprove pretty much anything.
What I would suggest though is not to have a knee jerk reaction every time a new piece of scientific “evidence” is published. Read, watch and listen to all sides of the discussion and scratch beneath the surface, also getting a credible opinion from someone you trust, then make your decision.
Another study I read found that a diet high in omega 3s can actually REDUCE the risk of getting prostate cancer.
So going back to the study from Seattle, let’s look into its validity.
It did not look into people taking fish oil supplements it was just an overview of omega 3 fatty acid levels in the blood, so we are unable to pinpoint if fish oil supplements were the exact cause.
A man called Dr Briffa also published an article on this subject after seeing the results of the study.
As you know I am not a doctor so I can only do so much in an attempt to question the results of this comprehensive study, so it is good that a man like Dr Briffa, who seems to promote and preach similar advice to myself had something to say on the subject.
He stated that the study was epidemiological in nature, which means that it only tells us about the relationship between the two rather than one thing (omega 3s) causes another thing (prostate cancer).
Dr Mark Hyman, analysed this very same study and he said:
What we can be sure of is that association does not prove cause and effect. If this had been an intervention design study, where half the participants got fish oil and half didn’t and they were followed for 20 years to see if they got prostate cancer, then you can say pretty definitively that they are connected. Bottom line, this type of study does not prove cause and effect. If I did a study on sunrise and humans waking up, I would find 100 percent correlation, but that doesn’t mean that the sun came up because you woke up. Correlation, yes; causation, no.
The authors of this study also presented data from similar studies, in the form of a meta analysis. The meta analysis showed:
A link between high omega 3 levels and increased risk of high-grade prostate cancer (higher levels were associate with a 51 per cent increased risk)