Matthew Herper

Matthew Herper, Forbes Staff


8/20/2009 @ 4:00PM

One Supplement That Works

A lot of nutritional supplements are quack medicines. Not fish oil.

In the late 1960s Danish physician Hans Olaf Bang became fixated on an epidemiological anomaly: Why did Greenland’s Inuit rarely get heart disease in spite of a high-fat diet consisting mostly of whale blubber and seal meat?

“We have to go up there and solve this riddle,” Bang told his protégé, Jørn Dyerberg, then 33 years old. In 1970 the two doctors cobbled together $6,000, flew to Greenland and collected blood samples from 130 Inuit. The cholesterol numbers were good but not enough to explain the healthy hearts. Back in the lab they used an old gas chromatograph to analyze Inuit blood. They found two chemicals they had never heard of before. The same chemicals didn’t appear in the blood of Inuit who had moved to mainland Denmark and switched to a Western diet.

The chemicals were fatty acids with a double bond between two particular carbon atoms, a pair beginning three units in from the end of the acid labeled “omega” by chemists. This particular variety of fatty acid is found in oil, which the Inuit ingest in salmon, a staple food. The researchers theorized that the omega-3 acids were responsible for the Inuit’s lower heart attack rate. “It was sheer luck,” says Dyerberg, who is now mostly retired.

So began a steady stream of research indicating that people should eat oily fish and maybe consume fish oil pills to protect their hearts. Salmon, sardines, mackerel and some types of nuts contain these essential fats, which the body cannot make itself. The two key ones for the heart are docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Researchers are still parsing all their varied effects. But, among other things, they reduce fatty particles in the blood called triglycerides and act as a mild blood thinner. They may even reduce the risk of sudden cardiac arrest by improving the electrical conductivity of heart cells.

Fish oil has become a multibillion-dollar business. Sales of over-the-counter fish oil supplements rose 18% last year to $739 million, according to Nutrition Business Journal. Americans buy another $1.8 billion worth of foods (such as margarine and peanut butter) fortified with extra omega-3s, says Packaged Facts. A patented high-concentration fish oil, Lovaza, is marketed by GlaxoSmithkline as a prescription drug for high triglycerides. Made by Norway’s Pronova Biopharma, it had global sales of $1 billion last year.

In the history of nutritional supplements there’s something striking about omega-3: the fact that it works. Much of the $25 billion a year that Americans spend on supplements is money down the drain.

How many natural remedies have bombed in scientific tests! Linus Pauling egged on people to swallow big doses of vitamin C, but large trials have shown no benefits. Vitamin E was supposed to protect the heart but also did little good in big trials. Selenium once looked like it might ward off prostate cancer, but a better study showed that the early result was a fluke. The recent recall of zinc nasal swabs for treating colds because they caused patients to lose their sense of smell is a reminder that just because something is natural doesn’t mean it is safe.

By contrast, a 1989 study of 2,000 men who had just had heart attacks found that those assigned to eat lot of fish or take fish oil pills were 30% less likely to die during two years of treatment. A 19,000-patient study in Japan found that purified EPA fish oil pills reduced major heart problems by 19% in heart patients already taking cholesterol-lowering statins like Lipitor and Zocor . Last year a study of 4,500 patients with heart failure (a deadly weakening of the heart muscle) found that a daily dose of Lovaza decreased the risk of dying by 7% over four years.

“I don’t think most physicians know there are gigantic studies–megastudies–that show quite a cardiovascular benefit,” says Chip J. Lavie, head of preventive cardiology at the Ochsner Clinic in New Orleans and a consultant to GlaxoSmithkline. “Doctors know about Lipitor, but they don’t know about this.”

The benefits to healthy patients are murkier and based on epidemiology, not controlled trials. But one 2004 analysis found that people who ate one fish meal per week lowered their heart disease risk by 15% and those who ate five servings of fish lowered their risk 40%. Fish oil “is the only supplement I recommend most everybody take unless they’re eating a lot of fish every day,” says James O’Keefe of the Mid-America Heart Institute, another Glaxo consultant. He argues that most Americans not eating at least 12 ounces of salmon or other oily fish per week are deficient in omega-3s.

Not everybody is ready to hand out fish pills like candy. Duke University cardiologist Robert Califf gives fish oil to his heart patients but calls the benefit modest. “I’m not going to go out and say everybody in the world should stock up on omega-3.” The American Heart Association recommends that healthy people should eat oily fish twice a week or more but suggests supplements only for those who already have heart disease. Another worry is overfishing, though one firm, Martek Biosciences , makes DHA from algae.

The main side effect of the pills is burping and a fishy aftertaste in the mouth. For patients without heart disease, cardiologists like O’Keefe and Lavie suggest 500 milligrams of omega-3s a day. You can get that with a supplement or two weekly servings of salmon. For those with heart problems, they recommend at least a gram a day (one Lovaza capsule or 12 capsules of many cheaper over-the-counter brands). At high doses DHA and EPA cause bleeding, so people taking more than 3 grams daily should do so under a doctor’s care, the aha says.

Not all omega-3s are created equal. Flax oil, for instance, is rich in omega-3s but not the DHA or EPA forms. It contains alpha-lineolic acid, which is converted into DHA and EPA in small amounts. The cardiac benefit may not be as big as the Eskimo effect.

Omega-3 pills almost began life as a drug, not a supplement. Decades ago British drug researchers tried to get a patent based on Dyerberg’s work but couldn’t because it was a natural product. It wasn’t until Pronova patented its high-concentration formulation in 1992 that a pharmaceutical market emerged. Pronova linked up with Solvay in Europe and Reliant Pharmaceuticals, a tiny company backed by the Pritzker family, in the U.S. GlaxoSmithkline bought Reliant for $1.7 billion in 2007.

With sales of fish oil pills growing fast, there is likely to be plenty of omega-3 hype in the future. In this case, though, there really is something to it.


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