Gavin Guard, Medical Director
Is Fish Oil Good for Heart Health?
Fish oil is a type of omega-3 fat
It has been shown to improve heart health as well numerous other health issues
There’s a few notes to consider before supplementing with fish oil (details below)
Improve your heart health with a multi-factorial approach that goes beyond just cholesterol
Is fish oil worth the hype?
You are most likely pretty familiar with fish oil. When you walk into the local grocery store or drug store, there seems to be at least a half a dozen fish oil brands and types. Chances are that you’ve taken them as a supplement a time or two.
But it seems as though the tides are shifting regarding fish oil over the last few years. At one point, they are a miracle supplement and at another point, they are a waste of money. It’s hard to know who to believe. Is this supplement helpful or a complete waste of time?
I’ve recently taken a deep dive into research on fish oil to bring you what you need to know. In this article, I walk you through:
What is fish oil
How heart disease is about more than cholesterol
How fish oil may be able to help heart health
Practical steps of how to use fish oil and determine if it’s working
What is fish oil?
Let me break down what fish oil is, so that you can understand how to get it through your diet and understand better how it works.
Dietary fat is one of 5 major macronutrients. It comes in different 3 different forms, or “variations”:
Saturated fat (e.g. lard, butter, animal fat)
Monounsaturated fat (e.g. canola oil, avocado oil, avocado, olives, olive oil)
Polyunsaturated fat (e.g. safflower oil, vegetable oils, fish, fish oil)
The terminology here just refers to the number of double bonds in the carbon chain of the fat molecule. The polyunsaturated fats are then further classified as:
Omega-6 fatty acids (vegetable, safflower, corn, sunflower oils)
Omega-3 fatty acids (fish oil, flaxseed oil, algae, chia seeds)
And then within omega-3 fatty acids, it can be even further broken down into 3 main molecules:
Alpha-linolenic acid (flaxseeds, chia seeds, algae)
Fish oil is especially rich in EPA and DHA. This is important to note since humans have a hard time converting alpha-linolenic acid into EPA and DHA, the major active omega-3’s. This is why you often hear health enthusiasts encouraging you to get enough omega-3s through fish oil (instead of flax, chia seeds, algae).
EPA and DHA have been studied for their cholesterol-lowering effects as early as the 1970s. It was around this time that many health organizations encouraged the population to eat enough of these health-promoting molecules.
This was important given the fact that an average person only eats 150 mg of EPA/DHA through their diet. This is in stark contract to fish-eating populations such as the Okinawan people who would eat ~2,000 milligrams per day. The Greenland Eskimos would get closer to 6,000-7,000 mg per day. Perhaps, this is why Eskimo populations suffered less heart attacks.
What you need to know is that:
Omega-3s are a healthy type of fat
Fish and fish oil is the optimal source of omega-3 fatty acids
Most of us don’t get enough omega-3 fatty acids through our diet
Inflammation promotes heart disease
Let’s now transition to discuss how omega-3s and fish oil ties into heart health. It’s important to know that cholesterol is not the only important thing to do with heart health. As a clinician, I also look at the other following factors to measure heart health and heart disease risk:
Immune system balance
Blood sugar balance
Genetic risk factors
Inflammation in particular is a powerful driver of heart disease. It is linked to many chronic health conditions including poor heart health. For instance, higher inflammatory levels (as measured by CRP levels) are predictive of future heart disease events. In other words, more inflammation means a higher chance of heart disease.
Furthermore, lowering inflammation can lead to less heart disease. In one study published in the New England Journal of Medicine, a drug designed to block inflammation, led to a 15% lower heart disease events in those with elevated baseline inflammation. However, this beneficial finding was not replicated in another study using a different anti-inflammatory drug.
Nonetheless, I believe that inflammation is:
Necessary for the onset of heart disease
Lowering inflammation will likely improve heart health
High triglycerides also promote heart disease
Whenever you get your annual cholesterol panel, your doctor also measures something called triglycerides. Unfortunately, these levels often go ignored unless they are very high.
However, new research is pointing to the fact that high triglycerides (along with inflammation) are also associated with heart disease. This is because high triglyceride levels change how other cholesterol particles behave - making them more prone to causing heart disease.
Studies have shown that genetic mutations that result in higher triglycerides are associated with higher heart disease risk. This means that triglycerides are causing heart disease.
Importantly, inflammation and high triglycerides have a two-way relationship:
High triglycerides lead to inflammation
Inflammation leads to high triglycerides (in fact, high triglycerides may be seen as an inflammatory marker and often decrease when you treat the root cause of inflammation
I share all of this information to show you that:
Heart disease is much more than just cholesterol (it also includes factors like inflammation and triglycerides).
If we can lower inflammation and triglycerides, we may be able to improve heart health.
Fish oil fatty acids reduce inflammation and high triglycerides
Fortunately, omega-3s can do both (lower inflammation and lower triglycerides)!
Research has shown that people have 35% lower triglycerides when they eat a diet high in omega-3s as compared to saturated fat or vegetable oil rich diets. Other types of studies have shown that supplemental omega-3s can lower triglycerides by 20-45% depending on the dose.
Also, omega-3s can lower inflammation levels. This has been shown by a multitude of well-designed studies.
Again, omega-3s can:
But do they actually lead to less heart disease? Let’s see…
Fish oil may lower heart disease rates
Now I want to be very careful here. Supplements and medications are not created equal. Only FDA-approved drugs have shown to reduce heart disease (we cannot say the same about supplements).
There’s two different ways a medication can improve heart disease rates.
First, it can reduce the rate of first-time occurrence of heart disease rates (primary prevention)
Or, it can lower the rate of another heart disease event (secondary prevention)
In regards to the first (primary prevention), results are mixed if fish oil can improve the first occurrence of heart disease. Two studies have shown that EPA alone can improve heart disease rates. The first study published in the Lancet (JELIS trial) randomized 19,000 participants on a cholesterol-lowering drug (statin) to either placebo or high-dose fish EPA (1,800 mg). The EPA drug resulted in a 19% reduced risk of heart disease events compared to placebo.
Another study (VITAL trial) gave both EPA and DHA to 25,000 healthy participants and saw a 20% reduction in heart attacks. However, not all data agrees and some studies show no improvement. However, those studies used lower doses.
The majority of other types of studies looking at reducing another heart disease event has shown no benefit of omega-3 drugs. However, many of these studies stopped early and may have not shown a potential benefit. The one study that did last a little longer (GISSI pre-venzione trial) did show a 15% reduction in death from all causes, heart attacks, and stroke.
Another study using EPA alone (REDUCE-IT trial) was a trial of 8,100 participants with type 2 diabetes or heart disease who were on a statin and high triglycerides. They were randomized to high-dose EPA (4g) or placebo. After 5 years, those in the EPA group had 25% lower risk of heart disease events and 20% lower risk of heart disease-related deaths.
Finally, another study (EVAPORATE trial) showed heart vessel plaque size reduced with the use of higher dose EPA.
Other benefits of fish oil
The benefits of fish oil go beyond just heart health. Other potential health benefits include:
Improvement of nervous system balance
Makes blood less sticky, but without the side effects of aspirin
Improved health of the lining of blood vessels
Improve heart failure (8% reduction in hospitalization, 9% lower death from any cause)
Should you take fish oil?
Again, I want to be careful here. I’m NOT suggesting that supplements can replace an FDA-approved drug meant for disease-lowering benefits. But with that said, I’d like to share how I use fish oil in practice.
1) Check your levels
First, get your omega-3 levels checked.
Genetics play a large role in how your body responds to taking fish oil so I recommend most of my patients get this measured. Make sure it’s looking at the omega-3 levels of the red blood cells (not the plasma).
The problem I see with many of the studies showing no benefit of fish oil is that they did NOT measure baseline omega-3 levels and thus, did NOT account for those who would probably benefit.
I have my patients aim for 8-12%. In one study, those with highest levels (>6.8%) had a 39% lower heart disease risk and 34% reduced risk of death from any cause.
It can take a while to see changes, so I recommend testing every 4 months until you have your levels in the 8-12% range.
2) I like the idea of fish oil supplementation in most of my patients
Given the low risk and high potential benefits (heart health, inflammation, brain health), I like the idea of fish oil supplementation. I usually have patients aim to get enough omega-3s from food first. A good rule of thumb is 3 servings per week of cold-water fish such as:
After that, we can layer in supplemental omega-3s. However, be careful with what you get in traditional supplements. I have patients get at least 1,000 mg of combined EPA and DHA. I have them take this with food to increase its absorption.
Unfortunately, it’s hard to get enough EPA and DHA from plant sources (flaxseed, algae) so I usually start with fish oil as a source of omega-3s.
3) Comprehensive approach to heart health
I encourage you to address your heart health in a comprehensive approach. Remember, heart disease has to do with much more than just cholesterol.
Also look at factors such as:
Cholesterol (including triglycerides)
Glucose (blood sugar)
Genetic risk factors
If you don’t know where to start, schedule a free health strategy session with me.
The Bottom Line
Fish oil is useful for heart health. It has been shown to improve many markers and some FDA-approved drugs containing purified fish oil have been shown to reduce heart disease risk.
I encourage you to get your levels measured and supplement wisely with a quality brand at a clinically effective dose.
Also, take a multi-pronged approach to heart health and don’t settle with the conventional standards. Heart disease takes years/decades to form so do everything you can now to reduce your risk.
I hope you found this information useful and helpful in your journey back to a healthier and happier life.
Like what you are reading? Learn more about how to take control of your health by signing up for the "5 Minute Health Makeover" below where I coach you through 3 pivotal strategies for better health.