Dear Doc: My wife just yanked the fish oil from our medicine chest because she read that it causes prostate cancer. Yikes. My dad died from prostate cancer. Have I been doing myself harm? What’s the scoop?

– Fretting Freddie

Dear Freddie: Your wife might be right, but before I delve into that evidence, let me say a word about fish oil. Years ago, we noticed that people who lived along the Mediterranean Sea had fewer heart attacks and strokes. Looking further, we found that eating fish was one key.

Enter the vitamin and supplement folks – a $25-billion-a-year industry, by the way. They started manufacturing fish oil like crazy after convincing us, doctors included, that this was just like eating fish.

Now, I ask you, if you bite into one of those fish-oil capsules, does it taste like fish?

Not at all. The oil is just one part of the fish, not the whole ball of wax.

So last year, I reported on a study of studies that examined 3,500 clinical studies of 70,000 patients and could not find any benefit of fish oil when it came to the bottom line: reducing heart attacks and strokes.

Don’t get me wrong – people on fish oil had better cholesterol numbers, specifically a reduction in their triglycerides. But who cares? If you swallow a pill every day, you want to know it’s doing something worthwhile, like preventing death from a heart attack.

So last year when I highlighted this Journal of the American Medical Association article, I got hate mail. Hate mail! People were passionate about their fish oil and didn’t like that I gave it a flunking grade.

I’m usually of the mind that says, “No harm, no foul.” If you want to spend your discretionary income on fish oil, then do it. But new data from the National Cancer Institute gave me pause. It showed that men who take fish oil just might be setting themselves up for prostate cancer.

The study is not the gold standard-type: a double-blind placebo-controlled study. But with this in mind, I have to think that maybe it does cause harm to swallow a capsule that clearly has no proven heart-attack prevention.

My spin: You decide. I dumped my oil and went for the gold – real fish. Study after study shows that eating two or more servings of fish a week is heart-healthy.

The best fish is fatty fish such as salmon, herring and sardines. The worst way to prepare it? You know. Deep fried with mayo and tartar sauce.

Once again, this reminds me that nature trumps industry every time. Nature trumps supplement manufacturers.

It’s not the oil that’s key, Freddie, it’s the fish.

Dr. Zorba Paster is a family physician, university professor, author and broadcast journalist. He also hosts a radio program at 3 p.m. Saturdays on WBFO-FM 88.7.