The media leaped onto headline news about a week ago that increasing levels of fish-type oils in the blood might significantly increase the risk of prostate cancer, especially aggressive cancers. At first blush this appeared credible and horrible news both at the same time. It was published in the Journal of the National Cancer Institute and run by investigators from the prestigious Fred Hutchinson Cancer Center in Seattle, WA.
Worn out patients, tired of yo-yoing research might understandably moan, “Oh no, now what?”
But if you look deeper into what the study assessed and what was reported, it’s actually a pretty fishy story. The good thing is that unveiling poor studies increases awareness about fish oil and health and how scary headlines make for sensationalism in the news. But the bad thing is that too many good men may now be throwing out good fish oil. Read on and perhaps be motivated to share this article.
The Study Is Stinky
The study was not carried out in a way to get these conclusions. Most significant is that this study was not initially organized to investigate omega-3 oils in the blood and the risk of getting prostate cancer.
The numbers came instead from a study on something else—the Selenium and Vitamin E Cancer Prevention Trial (“The Select Study”). Analyzing data from a study that is different from what the study was originally set up to evaluate, makes outcomes less ‘weighty’. This makes the conclusions coming out of this research, ‘soft’, unable to make the claims it did.
To really look at the link of prostate cancer and fish oils and get firm conclusions (which you can see in the articles below has already been done in this manner, and then fish oil emerged protective), we would need a prospectively designed trial with some men randomized to receive omega-3 fatty acids at various levels of intake and then followed over time to determine whether the omega-3 fatty acids did result in an increased risk for disease. Making firm conclusions from this present study design didn’t do this.
This soft data gets even mushier.
No true evidence of consumption of fish oils or fish oil supplements was ever documented. These researchers reported that men with the highest concentrations of omega-3 fatty acids in their blood had greater risk of getting prostate cancer. But the amazing issue, and this should make you really mad that this study gave you heart palpitations in the first place, was that within the body of the study there wasn’t any evidence that any of the men that were followed ate fish or took fish oil supplements at all! This means the omega-3s in their blood may have been coming in from other sources.
The measurement of omega-3 fatty acids was done only one time, at the beginning of the trial. Men were not assessed for how many fish meals they ate, or if they took fish oil supplements, or ate seeds and nuts and even avocadoes which also contribute to blood levels of these fatty acids.
Men in the control group were not thoroughly tested to rule out whether this comparative group had prostate cancer or not.
Tumor grading was questionable which gives inaccurate data of linking omega-3 fats to various levels of cancer.
None of the men tracked in this study actually had high levels of omega-3 fatty acids. The actual amount of the omega-3 fatty acids found in their blood was low.This study said that men with the highest level of fishy fats in their blood stream, EPA, DPA, and DHA, had a 71 percent increased risk of high-grade prostate cancer and a 44 percent increase in the risk of low-grade prostate cancer. Yet, the levels in their blood actually were fairly low. The patients without cancer had a value of 3.62 percent of omega-3 fats contrasted to the group that got cancer, who had omega-3 fatty acid levels at 3.66 percent. The inappropriate conclusion was that men with omega-3 fatty acids greater than 3.68 percent have a higher risk of aggressive prostate cancer.
The study conclusions run against what scientific and epidemiological data have clearly shown; that fish oil and even omega-3 fatty acids from other food sources, protects against prostate cancer, at even higher levels than those mentioned (and especially against the type of prostate cancer that travels throughout the body, metastasizes, and is thus deadlier).
If this study’s conclusions had been accurate, that fish oil causes a higher risk of nastier prostate cancer, then the countries that eat moderate to robust levels of fish would have way more cases of prostate cancer than they do.
But they don’t. In fact, both direct scientific and epidemiological studies show the opposite effect; that fish oil (and omega-3 fatty acids) protect against prostate cancer.
In populations like Japan and others who consume fairly high amounts of omega-3 oils (such as those that consume Mediterranean Diets), it has been repeatedly shown that they have less prostate cancer and related deaths when compared to other societies that eat less fish.
Some Non-fishy Fish Studies That Demonstrate that Fish Oil Protects Prostates
In an elegantly designed study to look at only the relationship between omega-3 fatty acids (EPA and DHA) in red blood cells and the risk of prostate cancer, New Zealand investigators found that greater levels of EPA+DHA were associated with a40 % decreased risk of prostate cancer.
47,866 US men without cancer were followed for 14 years and those with thehighest EPA+DHA intake had 26 percent less risk of developing prostate cancer.
Harvard School of Public Health followed 47,882 men for 12 years and found that eating fish protected prostate health. For each 500 mg of fish fat (omega-3 fatty acid rich), the risk of deadly metastatic prostate cancer decreased by 24%. Eating fish 3 times or more a week reduced the risk of prostate cancer. But the biggest protectionwas in protecting against metastatic cancer (when cells leave the prostate and travel throughout the body and can kill other cells and organs, this makes cancer deadly).
In a 2010 meta-analysis (looking at a number of studies to evaluate the trend), fish consumption wasn’t link to protection against prostate cancer, but it was linked to a 63% reduced rate of death once diagnosed with prostate cancer.
6,272 Swedish men and their fish consumption habits were followed for 30 years. Men who didn’t eat fish had a 2-3 times increased risk of developing prostate cancer compared with those who regularly consumed fish.
The Physician’s Health Study, following men for 22 years, linked high fish consumption defined as eating fish 5 or more times a week) with reducing the risk of prostate cancer death by 36%.
The Bottom Line
This study did not accurately link intake of omega-3 fatty acids with increasing the risk of prostate cancer, especially high-grade disease.
The media jumped on this and sensationalized it and the conclusions are flawed and sensationalistic.
How To Take Fish Oil Supplements
- General Health Protection: 1,000 mg of EPA+DHA along with 400 IU of mixed tocopherol vitamin Es with tocotrienols to protect against adverse oxidation of these oils inside the body.
- Fish Oil Therapeutics: 3,000 to 6,000 mg of EPA+DHA (depending on the condition and often the larger dosages are used for the beginning loading days, and then reduced to lesser maintenance amounts) with 400 IU of mixed tocopherol vitamin E along with tocotrienols.
- Trouble burping up fish oil? Try putting the plastic container of fish oil capsules in the freezer and taking the dose out right before swallowing the frozen capsules. This greatly reduces burping and dyspepsia from taking fish oil supplements in most people. There are also flavored capsules and oils that seem to be easier for some people, especially children, to tolerate.
Supplement/Fish Preparation Must-Knows: not all fish oils are the same.
Fish preparation affects oils. Fish prepared by broiling, baking or poached, are linked with healthy omega-3 levels. Fried fish are not. If you eat fried fish you are not getting the protective healthy omega-3 oils; even worse, you are getting damaged, toxic oils. The oils go through nasty changes during the frying process, which have been linked to higher risk of developing prostate cancer as well as other cancers.
We have a huge amount of information coming at us all day long, week in and week out. We have to be careful about the bad and scary news. Much of it is often not accurately interpreted, or it is not a true representation of the research, or it is tweaked to sell something. So know that this data was flawed. Take a deep breath and go enjoy a great fish meal and veggies with your loved ones!