Is Fish Oil Really Snake Oil?

February 11, 2014 by Dr. Steve Chaney

Does Fish Oil Reduce Heart Disease Risk?

Author: Dr. Stephen Chaney

One of my readers recently sent me a video titled “Is Fish Oil Just Snake Oil?” and asked me to comment on it. The doctor who made the video claimed that the most recent studies had definitively shown that omega-3 fatty acids, whether from fish or fish oil, do not decrease the risk of heart attack, stroke or cardiovascular death. He went on to say that the case was closed. There was no point in even doing any more studies.

My reader, like many of you, was confused. Wasn’t it just a few years ago we were being told that clinical studies have shown that omega-3 fatty acids significantly reduce the risk of heart disease? Hadn’t major health organizations recommended omega-3 fatty acids as part of a heart health diet? What has changed?

The answer to the first two questions is a resounding YES, and “What has changed?” is THE story. Let me explain.

Fish Oil And Heart Disease Risk In Healthy People

If we look at intervention studies in healthy people (what we scientists refer to as primary prevention studies) the results have been pretty uniform over the years. In a primary prevention setting, fish oil cannot be shown to significantly reduce the risk of heart disease (Rizos et al, JAMA, 308: 1024-1033, 2012).

That’s not unexpected because it is almost impossible to show that any intervention significantly reduces the risk of heart disease in healthy populations. For example, as I pointed out in recent Health Tips From the Professor (“Do Statins Really Work?” and “Can An Apple A Day Keep Statins Away?”) you can’t even show that statins significantly reduce heart attack risk in healthy populations.

If you can’t prove that statins reduce the risk of heart attacks in a healthy population, it should come as no surprise that you can’t prove that fish oil reduce heart attacks in a healthy population. To answer that question we need to look at whether fish oil reduces the risk of heart attacks in high risk populations.

Fish Oil And Heart Disease Risk In Sick People – The Early Studies

Most of the early studies looking at the effect of fish oil in patients at high risk of cardiovascular disease (what we scientists refer to as secondary prevention studies) reported very positive results.

For example, the DART1 study (Burr et al, Lancet, 2: 757-761, 1989) and the US Physician’s Health Study (Albert et al, JAMA, 279: 23-28, 1998) reported a 29% decrease in total mortality and a 52% decrease in sudden deaths related to heart disease in patients consuming diets rich in omega-3 containing fish.

Even more striking was the GISSI-Prevenzione study (Marchioli et al, Lancet, 354: 447-455, 1999; Marchioli et al, Eur. Heart J, 21: 949-952, 2000; Marchioli et al, Circulation, 105: 1897-1903, 2002). This was a very robust and well designed study. It looked at the effect of a fish oil supplement providing 1 g/day of omega-3 fatty acids on the risk of a second heart attack in 11,323 patients who had survived a non-fatal heart attack within the last 3 months – a very high risk group.

The results were clear cut. Over the next 3.5 years supplementation with fish oil reduced overall death by 15% and sudden death due to heart disease by 30% compared to a placebo. And, if you looked at the first 4 months, when the risk of a second heart attack is highest, the fish oil supplement reduced the risk of overall death by 41% and sudden death by 53%.

The authors estimated that treating 1,000 heart attack patients with 1 g/day of fish oil would save 5.7 lives per year. That is almost identical to the 5.2 lives saved per 1,000 patients per year by the statin drug pravastatin in the LIPID trial (NEJM, 339: 1349-1357, 1998).

No wonder the American Heart Association said that patients “could consider fish oil supplementation for heart disease risk prevention.”

Fish Oil And Heart Disease Risk In Sick People – The Latest Studies

However, the most recent studies have been uniformly negative. For example, the ORIGIN trial (Bosch et al, NEJM, 367: 309-318, 2012) treated 12,536 patients who were considered at high risk of heart disease because of diabetes or pre-diabetes with either 1 g/day of fish oil or a placebo. This was also a robust, well designed study, and it found no effect of the fish oil supplement on either heart attacks or deaths due to heart disease.

Similarly, a recent meta-analysis looking at the combined effects of 14 randomized, double-blind, placebo-controlled trials in patients at high risk of heart disease found no significant effect of fish oil supplements on overall deaths, sudden death due to heart disease, heart attacks, congestive heart failure or stroke (Kwak et al, Arch. Int. Med., 172: 686-694, 2012).

No wonder you are confused by all of the conflicting studies. You must be wondering: “Is the American Heart Association wrong?” “Are fish oil supplements useless for reducing heart disease risk?”

What Has Changed Between The Early Studies & The Latest Studies?

When a trained scientist sees the outcome of well designed clinical studies change over time, he or she asks: “What has changed in the studies?” It turns out that a lot has changed.

1) In the first place the criteria for people considered at risk for heart attack and stoke have changed dramatically. Not only has the definition of high cholesterol” been dramatically lowered, but cardiologists now treat people for heart disease if they have inflammation, elevated triglycerides, elevated blood pressure, diabetes, pre-diabetes or minor arrythmia.

For example, the GISSI-Prevenzione study recruited patients who had a heart attack within the past three months, while the ORIGIN study just looked at people who had diabetes or impaired blood sugar control. While both groups could be considered high risk, the patients in the earlier studies were at much higher risk for an imminent heart attack or stroke – thus making it much easier to detect a beneficial effect of omega-3 supplementation.

2) Secondly, the standard of care for people considered at risk for heart disease has also changed dramatically. In the earlier studies patients were generally treated with one or two drugs – generally a beta-blockers and/or drug to lower blood pressure. In the more recent studies the patients generally receive at least 3 to 5 different medications – medications to lower cholesterol, lower blood pressure, lower triglycerides, reduce inflammation, reduce arrhythmia, reduce blood clotting, and medications to reduce the side effects of those medications.

Since those medications perform many of the beneficial effects of omega-3 fatty acids, it is perhaps no surprise that it is now very difficult to show any additional benefit of omega-3 fatty acids in patients on multiple medications.

The bottom line is that we are no longer asking the same question. The earlier studies were asking whether fish oil supplements reduce the risk of heart attacks or cardiovascular death in patients at high risk of heart disease. The more recent studies are asking whether fish oil supplements provide any additional benefits in a high risk population that is already on 3-5 medications to reduce their risk of heart disease.

However, the people who are writing the headlines you are reading (and the videos you are watching) are not making that distinction. They are pretending that nothing has changed in the way the studies are designed. They are telling you that the latest studies contradict the earlier studies when, in fact, they are measuring two different things.

Is Fish Oil Really Snake Oil?

Was the doctor who made the video “Is Fish Oil Just Snake Oil?” correct in saying that omega-3 fatty acids are ineffective at reducing the risk of heart disease? The answer is yes and no.

If you take the medical viewpoint that the proper way to treat anyone at the slightest risk of heart disease is with 3-5 medications – with all of their side effects, the answer seems to be pretty clear cut that adding fish oil to your regimen provides little additional benefit.

However, that is not the question that interests me. I’d like to know whether I can reduce my risk of heart attack and cardiovascular death by taking omega-3 fatty acids in place of those drugs – as the original studies have shown.

I’m sure many of my readers feel the same way.

The Bottom Line

Studies performed prior to 2000 have generally shown that fish oil supplements reduce the risk of a second heart attack in patients who have previously had a heart attack. One study even suggested that they were as effective as statin drugs at reducing heart attack risk in this population.

Recent studies have called into question the beneficial effects of fish oil supplements at reducing the risk of heart disease. However, these studies were performed with lower risk patients and the patients were on 3-5 medications to reduce their risk of heart attack or stroke.

The recent studies are no longer evaluating whether fish oil supplements can reduce the risk of heart disease. They are asking whether they have any additional beneficial effects for people taking multiple medications. That’s a totally different question.

So ignore the headlines saying that fish oil is snake oil. If you are content taking multiple medications to reduce your risk of heart disease, it is probably correct to say that omega-3 fatty acids provide little additional benefit.

However, if you are interested in a more holistic, drug-free approach to reducing your risk of heart disease, I still recommend omega-3 fatty acids as part of a heart healthy diet, as does the American Heart Association.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Does An Apple A Day Keep Statins Away?

February 4, 2014 by Dr. Steve Chaney

The Latest On Diet And Heart Health

Author: Dr. Stephen Chaney

In a previous “Health Tips From the Professor” I talked about how difficult it has been to prove that statins significantly reduce the risk of heart attack or cardiovascular deaths in a low risk population group. Now let’s look at the other side of the coin – lifestyle change –and ask how effective lifestyle change is at reducing the risk of cardiovascular disease.

You’ve all heard the saying “An apple a day keeps the doctor away”. It dates back to Victorian England. It was the public health message of the day – much simpler and more concise than our current food guide plate.

A prominent British doctor and his research team recently decided to see how accurate that saying really was. But they took their study one step further. They compared the effectiveness of an apple a day versus a statin a day at reducing the risk of cardiovascular deaths (Briggs et al, British Medical Journal, 3013;347:f7267 doi: 10.1136/bmj.f7267).

The results of that comparison may surprise you.

Does An Apple A Day Keep Statins Away?

They used the data from the Cholesterol Treatment Trialist meta-analysis to estimate the effectiveness of statin drugs at reducing cardiovascular deaths. They used the data from the PRIME comparative risk assessment model to estimate the effectiveness of apple a day at reducing cardiovascular deaths.

They asked what would happen if each of them were the primary intervention for the entire British population over 50 who were not currently taking statin drugs (17.6 million people).

They assumed a 70% compliance rate for both interventions. In simple terms that means they assumed that 70% of the population would actually do what their doctors told them. (Patients must be more compliant in England than in the US).

The results were interesting. They estimated that:

Giving a statin drug each day to 17.6 million people would reduce the number of cardiovascular deaths by 9,400.

Giving an apple each day to the same 17.6 million people would reduce the number of cardiovascular deaths by 8,500 (not significantly different).

But when they looked at side effects and cost the two interventions were significantly different.

Giving a statin drug each day to 17.6 million people would also cause some significant side effects. The authors estimated that it would lead to:

1,200 excess cases of severe muscle pain and weakness
200 excess cases of rhabdomyolysis (muscle breakdown, which can lead to irreversible kidney failure)
12,300 excess cases of diabetes

On the other hand, there are no known side effects to an apple a day.

The statin intervention would cost an estimated $295 million. In the case of apples, you would presumably be substituting a more healthy food for a less healthy food so there would be little or no net cost.

And the 70% compliance rate is probably wildly optimistic. Some experts have estimated that up to 50% of patients discontinue their statin medications within the first year because of side effects or cost.

Is There A Scientific Basis For Those Estimates?

Of course, we all know that the “apple a day…” saying was never meant to be taken literally. It was just a simple way of saying that a good diet will reduce the risk of disease.

It turns out that there was another major study on the effect of dietary fiber on reducing the risk of cardiovascular disease in the very same issue (Threapleton et al, British Medical Journal, 2013;347:f6879 doi: 10.1136/bmj.f6879). It was a meta-analysis that combined the data from 22 previously published studies.

This study showed:

For every 7 g/day increase in dietary fiber the risk of both heart attacks and cardiovascular disease decreases by 9% (7 grams of dietary fiber could come from one serving of whole grains plus one serving of beans or lentils or from two servings of fruits or vegetables).

For every 4g/day of fruit fiber (equivalent to one apple) the risk of heart attacks decreases by 8% and the risk of cardiovascular disease decreases by 4%.

The numbers are similar for every 4 g/day of vegetable fiber.

Another recent study showed that consumption of 75 g/day of dried apple (equivalent to two apples a day) lowered total cholesterol by 13% and LDL-cholesterol by 24% in post-menopausal women (Chai et al, J. Acad Nutr Diet, 112: 1158-1168, 2012). That’s comparable to the cholesterol reduction achieved with statin drugs.

The Bottom Line

If you have not previously had a heart attack and are at relatively low risk, something as simple as adding an apple a day (in place of less healthy foods) may just as effective as statin drugs at reducing your risk of cardiovascular death without the side effects and cost of the drugs.

This is not really new information. For years both the American Heart Association and the National Institutes of Health have recommended that Therapeutic Lifestyle Changes (weight loss, healthy diet and exercise) should be tried BEFORE drug treatment to reduce the risk of heart disease.

So if you want to avoid statins, tell your doctor that you are willing to make the needed lifestyle changes to reduce your risk of heart disease and stick with it. Lifestyle changes are hard, but clinical studies clearly show they can often be just as effective as drug therapy, without the cost and side effects.

Don’t misunderstand me. I’m not advocating avoiding statin drugs if they are absolutely necessary. If you have had a heart attack or are at high risk of heart disease, it is clear that statins can save lives. Even here I would recommend talking with your physician about incorporating therapeutic lifestyle change into your regimen. It may allow them to minimize the dose, and therefore the side effects, of the statin drugs.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Are Cholesterol Lowering Drugs Right For You?

January 11, 2023November 19, 2013 by Dr. Steve Chaney

Do Statins Really Work?

Author: Dr. Stephen Chaney

Statins – those ubiquitous drugs used to lower cholesterol levels – are big business!

Over 20 million Americans are currently being treated with statin drugs at a cost that runs into billions of dollars every year. And cardiologists have just recommended that another 20 million Americans consider using cholesterol lowering drugs. 44% of the men and 22% of the women in this country are now being told that they should be using statin drugs.

Some of my cardiologist friends are so convinced that statin drugs prevent death from heart attacks that they have said, only half-joking, that we should just add statins to the water supply.

Are Cholesterol-Lowering Drugs Right For You?

Is the faith of doctors in the power of statin drugs to prevent death from heart disease justified? To answer that question in full we need to look at people who have already survived a heart attack and people who have never had a heart attack separately.

If you’ve already had a heart attack the evidence is clear cut.

If you have had a heart attack, there is good evidence that statins will reduce your risk of dying from a second heart attack.

In the technical jargon of the scientific world that is referred to as secondary prevention.

But what about those millions of Americans who are being prescribed statin drugs who have never had a heart attack? This is something we scientists refer to as primary prevention.

What Do The Studies Actually Say About Statins And Primary Prevention?

Here the evidence is not clear at all. Two major reports have cast doubt on the assumption that statins actually do prevent heart attacks in people who have not already had a first heart attack.

In the first study, Dr. Kausik Ray and colleagues from Cambridge University in England performed a meta-analyis of 11 clinical studies involving over 65,000 participants (Ray et al, Arch. Int. Med., 170: 1024-1031, 2010). They focused on those participants in the studies who had not previously had a heart attack (primary prevention).

They found that the use of statins over an average of 3.7 years had no statistically significant effect on mortality. In short, statins had no effect on the risk of dying from heart disease or any other cause.

Dr. Sreenivasa Sechasai, one of the doctors involved in the study, said “We didn’t find a significant reduction in death despite having such a huge sample size. This is the totality of evidence in primary prevention. So if we can’t show a reduction with this data, it is unlikely to be there.”

The second study was a Cochrane Systemic Review of statins published January 19th, 2011. It stated that there was not enough scientific evidence to recommend the use of statins in people with no previous history of heart disease with some caveats (see below).

To help you understand the significance of that conclusion, let me give you a bit of background:

First you need to understand that the Cochrane Collaboration is an independent, non-profit organization that carefully reviews the scientific evidence behind medical treatments and proposed medical treatments.

Cochrane Reviews are considered the “Holy Grail” of evidence-based medicine (ie. medicine based on the best scientific evidence rather than what the pharmaceutical companies would have you believe).

So when a Cochrane Review concludes that there isn’t enough evidence to recommend use of statins in patients with no prior history of heart disease that is pretty big news in the medical world.

How Should These Studies Be Interpreted?

Please don’t misinterpret what I am saying. The Cochrane Review said that statin drugs are overprescribed, but it did not say that everyone who has not had a heart attack will not benefit from statins. It said that there are a number of risk factors that need to be considered in evaluating individual patients for statin use.

Simply put, that means that it is not as simple as saying that everyone with no previous history of heart disease should not be on statin drugs.

If you are currently taking statin drugs and you have no previous history of heart disease, you may want to discuss with your physician whether the Cochrane Review of statin drugs changes their opinion of whether se of those drugs is still warranted for you.

But the bottom line is that only your physician is trained to take into account all of the factors that increase your risk of heart disease and the best therapeutic approach for reducing your risk of heart attack.

There Is A Double Standard In The Medical Community

More importantly, these studies highlight the difficulty in showing that anything works when you start out with a healthy group of adults with no prior evidence of disease (primary prevention).

And, the way that doctors have responded to primary prevention studies shows that there is a double standard in how primary prevention trials are interpreted in the medical community. For example:

There is no good evidence that statins prevent fatal heart attacks in healthy people.

However, because statins do work in high risk patients, most doctors recommend their use by millions of Americans who have never had a heart attack.

There is also no good evidence that nutrients like vitamin E and omega-3 fatty acids prevent fatal heart attacks in healthy people.

However, there is evidence that both vitamin E and omega-3 fatty acids prevent heart attacks in high risk patients, yet most doctors will tell you they are a waste of money.

It is food for thought.

The Bottom Line

1) Statin drugs clearly save lives when used by people who have already had a heart attack.

2) On the other hand, there is no proof that statin drugs prevent heart attacks in people who have not previously had a heart attack

3) Statin drugs do have side effects. Increased risk of diabetes, liver damage, muscle damage and kidney failure are the best documented, although memory loss has also been reported.

4) I am not recommending that you stop using statin drugs without consulting your doctor. I am suggesting that you discuss the benefits and risks of statin drug use with your doctor.

5) Perhaps the most important poin tto come out of these studies is that it almost impossible to prove the benefit of any intervention in a primary prevention trial. If you can’t prove that statins work in healthy people, it is not surprising that it is difficult to prove that other interventions work.

6) Finally, the way that these studies have been interpreted shows that there is a clear double standard in how the medical community evaluates primary intervention trials.

Statin drugs don’t show any benefit in a primary prevention setting, yet most doctors still recommend them.

Vitamin E and omega-3 fatty acids don’t show any benefit in a primary prevention setting, and most doctors recommend against them.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.