A particularly common piece of health care and diet advice is to eat fish on a regular basis – with many sources recommending eating fish two to three times a week.
This advice is largely focused on the omega-3 fatty acids in fish, and the way that these play a key role in how fish oil lowers triglycerides.
At the same time, many other health benefits have been associated with fish, especially due to the range of beneficial nutrients present in fish.
Why are Triglycerides Important?
Triglycerides are a specific type of fat that is found in the body and is often monitored at the same time as cholesterol levels and blood pressure.
While cholesterol and its potential role in heart disease risk is well-known (although, that area is under considerable debate), fewer people are aware of the importance of also paying attention to triglycerides.
Frequently, people with high overall cholesterol will also have high levels of triglycerides (1).
As a general rule, a person should receive a score of less than 150 for their triglyceride level while a level of greater than 200 is considered to be high and 500 or more is considered to be very high (2).
You do need some level of triglycerides in your blood, because they are associated with energy (3).
High levels of triglycerides can be caused by a range of factors, including a very high carbohydrate diet, a lack of physical activity, obesity and the consumption of too much alcohol. Genetic factors or underlying diseases can also play a role (4).
Additionally, some medications can increase your level of triglycerides, including birth control pills, diuretics and beta-blockers (5).
Triglycerides are important, because they provide an important indication of heart health.
By extension, decreasing triglyceride levels is thought to play a key role in reducing heart disease risk and promoting health overall.
Triglycerides and Fish Oil
There are a few different sources of omega-3 fatty acids, including spinach and walnuts, but the most significant source of omega-3 is fish oil.
Although it is often overlooked, there are actually three main types of omega-3 fatty acids that we focus on. These are DHA (docosahexaenoic acid), EPA (eicosapentaenoic acid) and ALA (α-linolenic acid).
DHA and EPA are long-chain forms of omega-3, and this is the form that is found in fish and fish oil.
In contrast, ALA is a short-chain form and it is found in plants.
The human body uses the long-chain form and ALA has to be converted into that form before it is used. This process takes time – and it’s one of the reasons that DHA and EPA are often considered to be superior types of omega-3 (11).
Research is still ongoing about the impacts of these different forms on health, but most of the time the emphasis is on getting sufficient DHA and EPA to promote the best heart outcomes (12).
Indeed, EPA and DHA have a well-documented and established history of lowering triglyceride levels (13).
A large-scale and in-depth examination of current research found significant evidence for the potential of omega-3 fatty acids to decrease cardiovascular risk. This was true whether the omega-3 came from fatty fish or from supplements (14).
The significance of these compounds has led to a growing interest in fish oil supplements being prescribed as medication for patients with high levels of triglycerides (known as hypertriglyceridemia).
Research into Fish Oil and Triglycerides
Human research has shown that the impact of omega-3 fatty acids on triglycerides occurs in a dose-dependent manner (15).
One study looked at this impact in an examination of the blood triglyceride levels of ten participants fed a control diet followed by a diet containing fish oil.
Following the experimental intervention, the level of triglycerides in the blood was significantly decreased.
The authors determined that the impact of omega-3 on triglycerides was the result of inhibiting the synthesis of triglyceride (16).
Another study found a similar outcome in an examination of seven subjects (17). Other studies have also shown that fish oil supplementation can decrease triglyceride levels and helps promote clearance of triglycerides (18,19,20).
This can make fish or fish oil an important approach for improving heart health and longevity overall.
Additionally, studies have found that fish oil can act to decrease the risk of other cardiac events, including strokes and even death (21).
Fish Oil and LDL
Some research into fish oil has found that while fish oil can help lower triglycerides, it may also raise levels of LDL cholesterol.
This impact seems to be the result of DHA, as EPA-only formulations do not have this effect (26).
Despite this, other research has suggested that EPA and DHA work in a complementary manner – meaning that some benefits are likely to only occur from supplements that contain both or from fish in the diet (27).
Fish Oil versus Actually Eating Fish
Without a doubt, fish is healthy, and eating fish itself is the best way to maximize your health benefits.
Some people find it difficult to eat fish multiple times in a week.
That’s especially true for people who don’t particularly like fish or people on a very limited budget.
One alternative is fish oil supplements.
Because of this, it is best to eat fish on a regular basis if you are able to, but if not, taking fish oil provides considerable advantages.
Some people don’t like fish oil because it can result in their mouth tasting like fish afterward or they have burps that taste like fish.
Neither of these is very nice, and they can be particularly bad if you don’t really like the taste of fish.
However, this problem really only occurs if the fish oil is taken on its own, rather than right before a meal.
This isn’t true for everyone, but many people have found that simply taking their fish oil at mealtimes helps to ensure that they don’t get a fish-like taste from the supplement.
Because fish oil is a supplement, it is not regulated by the FDA.
This means that different brands of fish oil can vary in how much omega-3 is actually in them, making some much less effective at lowering triglycerides than others.
For people who have coronary artery disease or a different heart condition, the amount of omega-3 needed may be more than can be reasonably obtained within a diet.
For these people, taking supplements can be an effective way promoting positive heart health (28).
Omega-3 is a compound that has been part of the human diet throughout history, particularly as many populations have relied on fish as a food source.
As a consequence of this, the FDA has recommended that up to three grams per day of omega-3 is safe for regular inclusion in the diet.
When taking this omega-3 from fish, it is recommended to avoid eating the skin wherever possible, as this can contain significant amounts of mercury.
Many fish oil supplements are free from mercury, but some low-quality supplements may contain mercury (29).
Likewise, there is also the risk that sellers are mislabeling supplements. This can happen and it is a particularly significant problem in the supplement industry because of the lack of regulation (30,31).
This makes it important to consider the source of any fish or fish oil carefully and look for trusted sellers.
While it is almost impossible to know for certain the quality of any supplement you buy, looking for news reports and stories online can often provide a strong indication of which brands are legitimate and which have failed tests.
Despite these issues, the inclusion of fish oil in the diet can be critical for supporting heart health as well as providing many other nutritional benefits.
Fish Oil Dosage
One of the challenges with supplementing is getting the right dosage.
If you use a dosage that is too low, you may end up not getting health benefits from the fish oil – and wasting time and money in the process.
Some people also choose to buy larger capsules, believing that these will have more fish oil, but these supplements are often less concentrated than smaller capsules. That pattern highlights the importance of paying close attention to the actual dose in different supplements.
One study examined different types of supplements to see which had the most significant impacts on triglycerides (32).
The four supplements, along with their recommended daily dose can be seen in the graph below.
The order of the supplements in the graph reflects the outcomes of the study, with the leftmost supplement (Concentrated Triglyceride Fish Oil) having the greatest impact on cardiovascular disease risk reduction and the rightmost supplement (Phospholipid Krill Oil) having the least impact.
Interestingly, you would get that same order if you ordered the supplements based on their total level of omega-3 levels (i.e. DHA + EPA levels), as such:
This offers pretty strong evidence that the level of omega-3 has a strong impact on the overall effectiveness of the supplement.
A literature review into omega-3 and cardiovascular risk indicated evidence for health benefits for doses from 0.5 to 1.8g of DHA + EPA per day (33).
One animal study found that weekly large doses of omega-3 were more effective than smaller doses daily (34).
More research needs to be done to know whether the same pattern is true in humans, but it is an interesting outcome regardless.
Overall, these outcomes suggest that if you are getting sufficient amounts of omega-3 fatty acids, they can significantly lower the risk of heart disease – although (as always), research is ongoing.
There are many different fish oils on the market, which is why we have compiled a list of 8 high quality fish oil brands that you can trust. These are all reliable products and can be a good way to get the DHA and EPA that you need into your diet every day.