Fish oil has long been considered valuable in terms of heart health, blood pressure and helping achieve healthy cholesterol levels.
But recent research has totally changed our understanding of how fish oil affects cholesterol.
It can lower cholesterol by as much as 30% in some cases.
So here we are going to look at just how fish oil/Omega 3 affects our cholesterol levels, and how much it takes to achieve those healthier levels.
Cholesterol 101 – It’s Not As Bad As You Think
Firstly let’s briefly define what cholesterol is, and how it affects the body.
Your body needs cholesterol, and actually makes it all by itself in the liver. Our bodies use it to make cells, for making vitamin D and hormones.
We cannot function without cholesterol.
So there is really no such thing as good or bad cholesterol.
To transport cholesterol around, our bodies use something called lipoproteins. These are just little packages that move through our blood delivering various substances. You have probably already heard of two of these called LDL (low density lipoprotein) and HDL (high density lipoprotein). There are others too.
But LDL is not ‘bad cholesterol’ because it’s not even cholesterol. It’s a lipoprotein, and just the delivery guy.
LDL carries fresh cholesterol, and HDL carries used cholesterol, most of which is recycled by the liver.
So why is LDL often referred to as ‘bad’?
Because too much cholesterol in the blood stream is known to contribute to clogging up arteries (atherosclerosis). And LDL is the delivery guy while HDL is the clean-up guy.
Which means of course you want the two in balance. If you had no LDL your body could not function. So LDL itself is not ‘bad’ either, but having too much of it can be.
What About ‘Triglycerides’?
This is something else that crops up when you get your cholesterol levels tested.
Triglycerides are also transported by our friends the lipoproteins. They should not be considered ‘bad’ either, because they are simply stored energy.
They become relevant because they are one of the unknowns in the formula to work out your cholesterol levels. If they are high it makes your overall cholesterol levels high. Which doesn’t necessarily mean anything, but high triglyceride levels may be a contributor to clogging arteries  and can indicate other problems.
What Are Normal Healthy Cholesterol Levels Anyway?
Firstly, bear in mind when you have your cholesterol levels tested that the results are not entirely reliable. Your LDL level is not actually measured, it’s an estimate. And the formula used to calculate your levels (the Friedewald equation, from 1972 ) makes some assumptions.
The results can also vary significantly from test to test. How stressed you are at the time of the test, the time of day, if you fasted properly or not. Even reasons as seemingly obscure as how long it was since you had some sun exposure (remember that cholesterol is used to make vitamin D, and sun on our skin is when we make vitamin D). All can affect your test results!
That said, various organizations have produced guidelines as to what they believe are healthy cholesterol levels.
In the USA people are advised total cholesterol should be below 200 mg/dL, that LDL should be below 100 mg/dL and triglycerides below 150 mg/dL . Confusingly the UK and Australia suggest figures as low as 155 mg/dL and as high as 213 mg/dL respectively.
Just remember that requirements for accuracy and precision allow for errors anywhere from 15% below to 15% above the real value . And that the ‘real value’ can vary as mentioned above anyway.
Does Fish Oil Help Lower Cholesterol?
Getting back to fish oil. Whether or not fish oil (or rather the Omega 3’s in fish oil) can reduce your cholesterol levels depends on how you define ‘cholesterol’. Which is why we just went over what all those terms really mean.
But here’s what has been shown so far from studies:-
- Triglycerides: Omega 3 can reduce triglycerides by as much as 30% 
- HDL: Omega 3 can raise HDL levels (considered the ‘good’ one) 
So fish oil can lower triglycerides, and is good for lowering cholesterol.
What is not so clear though is if fish oil/Omega 3 is good for lowering LDL cholesterol. A number of studies have shown it may well do so, by as much as 32.5% . But others show it may actually increase them marginally . The difference could simply be in the inaccuracies of measuring and those other factors that affect our levels.
But that’s not the whole story of course.
What Else Does Fish Oil Do..?
Of course, the main reason we worry about our cholesterol levels in the first place is due to concerns over increased risk of heart disease and strokes.
But cholesterol is not the only risk factor. And fish oil has also been shown to help with all of these other risk factors:-
- can help prevent artery clogging problems 
- it can reduce blood pressure in high blood pressure cases 
- has a blood thinning quality, reducing likelihood of those clots that lead to heart attack and stroke 
- reduces inflammation 
Even these are not the limit of the benefits of Omega 3, as these fascinating fatty acids have at least some impact on nearly every area of the body.
How Much Fish Oil To Lower Cholesterol?
Typically a ‘maintenance’ type dose of Omega 3 is suggested to be around 300 – 600 mg combined of the Omega 3’s EPA and DHA per day. This should be enough to provide the cholesterol reducing and other benefits above.
For patients with coronary heart disease (CHD), the AHA recommends 1,000 mg (= 1g) of combined EPA/DHA per day . And to lower triglycerides they recommend 2,000 mg to 4,000 mg (that is, 2g to 4g) of EPA and DHA combined .
The FDA considers a safe level to be up to 2,000 mg of EPA and DHA combined per day from a supplement source. Although the EFSA, their European counterpart says up to 5,000 mg per day is not a concern.
It’s wise to talk this through with your doctor anyway even if you consider yourself perfectly healthy. But obviously if you have any concerns, pre-existing conditions or take any medications then you must consult with your doctor first to determine how much fish oil is safe to lower your own cholesterol levels.
High & Low Cholesterol Foods – Big Changes!
The most important thing to understand about cholesterol in food, is that the advice dramatically changed in 2015.
Before 2015, we were told to limit our cholesterol intake from food to less than 300 mg per day. As we have learned more about the way cholesterol works in the body, the DGA (Dietary Guidelines for Americans) has changed that advice so there is now no limit .
Because as the DGA puts it, there is no longer any adequate evidence for placing a limit on dietary cholesterol. It has no significant effect on the cholesterol levels in our blood . In other words, eating cholesterol does not raise our cholesterol levels. The connection just isn’t there.
So eggs for example are not the ‘high cholesterol food to be avoided’ that they used to be. They are actually packed with great nutrition. This also means there are no high LDL cholesterol foods to avoid. High cholesterol foods do not mean high blood levels or test levels, just as foods with low levels will not reduce high test results.
That said, you still need to be sensible. Fats are not bad and never have been, not even saturated fat. Just keep balance in mind. Trans-fats however are bad and should be avoided as much as possible – these are not ‘real’ fats but fats that are generated mainly by high levels of processing. But then we already know highly processed foods are not good choices anyway.
Food can however affect your cholesterol levels in other ways. As we have already covered with fish oil specifically.
How To Lower Cholesterol? The Bottom Line!
So some foods, dietary and even lifestyle changes can make a difference to your cholesterol levels.
All of these simple remedies have been shown to be useful ways to lower cholesterol:-
- get some regular exercise
- cut sugar out of your diet
- get your weight down to a healthy level (the above helps do that anyway)
- take a quality Omega 3 supplement (or eat enough fish)
- try and reduce stress in your life
- eat more soluble fibre
Sometimes the answers can be quite simple. Deep down we tend to know what is generally good for our health and what isn’t. So doing more of the good stuff and less of the ‘couch surfing eating junk food’ can benefit all areas of our health.
What About Statins? Not So Good After All!
Statins have become one of the most popular drugs over the last 20 years. And the evidence does show they work, but I find them concerning for a number of reasons.
Statins work by reducing your bodies ability to create cholesterol. But as we covered, our body does need cholesterol, and makes it for a very good reason.
Statins are also frequently sold as a ‘no downside’ option, so ‘everybody should be taking them’. Yet they do have side effects ranging from muscle pain to increased diabetes risk , and worse.
Yet Pfizer made over $1.8 BILLION from selling ‘Lipitor’ (one of the most popular brands) in 2015 alone. How many of those people actually needed to take it?
If you don’t need to take a drug, I can’t see any good reason why a doctor would be recommending it. And even for those with elevated levels, it would seem wiser to monitor (to try and rule out inaccurate readings and natural variations) and only prescribe statins where simpler approaches have not worked.
Incidentally, if you do take a statin, read up on statins and CoQ10 depletion. It may help alleviate some of those potential side effects.
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