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In this article, we look at Why Fish Oil is BAD for You. In addition to the dangers fish oils cause, we see that the scientific studies are inconclusive, at best, regarding the effectiveness of fish oils for improved health.
Instead, we understand that the best source of omega-3 fatty acids is a change in diet and often times fewer supplements.
Studies show only short term benefits from taking many supplements, but with long term use of fish oils especially, we see danger signs, heart and liver symptoms and even death.
My personal testimony? After switching away from fish oils and high doses of vitamins A and D, often pushed by the same doctors: Hashimoto’s in remission (off meds for years now!), histamine intolerance gone, depression gone, GI tract performing well (no more digestive aids needed!), sleeping well with zero sleep aids (including herbs) and more …
Why science doesn’t prove fish oils are good for you
Articles that seek to prove the healthfulness of a supplement, by linking to studies, oftentimes draw inaccurate conclusions. In fact, it’s easy to draw false conclusions from studies, and there are times when this false information is even financially motivated (such as the multi-billion dollar fish oil industry).
Doctors may innocently believe that fish oils are healthy, but that doesn’t mean they are correct.
As we’ll see below, studies are often performed with some level of nutritional ignorance, as surprising as this may seem. We’ll see one example below where control groups were fed oils like corn oil or mineral oil, which are highly inflammatory, so fish oil had a better outcome for patients. This, of course, does not prove that fish oil is good for us.
The logic behind avoiding fish oils
Anyone who eats a whole food diet can vouch for the oddity of removing an animal’s fat and eating extra of it for improved health.
This dietary concept of eating extra fat has been linked to certain indigenous cultures, but as more doctors are discovering in recent years, in part due to the rise of fatty liver and heart disease, those claims don’t hold up.
From cod liver oil to various fish oils
While countering the overeating of omega-6 rich foods with omega-3 oils may help some patients short term, by improving the ratio of good fats to bad fats (so to speak), there is no evidence that taking omega-3 fish oils is actually beneficial to the human body.
But, as we’ll explore more below, there is now evidence that this supplement can lead to serious heart and liver problems.
Re-interpreting the studies
Many doctors in the U.S. believe that taking fish oils may improve one’s health. Some have even created their own fish oil supplements and believe strongly in their anti-inflammatory properties.
One example is Chris Kresser. He’s a functional medical doctor whose work I used to like, but I no longer believe he’s on the right track. I came across a video of him recently and took a screenshot of his face, because I was shocked by how much he’d aged just in the last few years. Ironically, the ad was for his new fish oil supplement! I include the screenshot photo so you can see. Just five years ago, he looked so much younger. (Notice not only the wrinkles, but the red face, tight, drawn lips and face and weight loss. To me, these are possible signs of liver toxicity.)
(Side note: I mean no disrespect to him personally, but I think it’s noteworthy for this discussion. Unfortunately, we do not know the true health of many health practitioners. But I have sometimes had access to this information and been surprised by the damage these gurus are doing to themselves and millions of others. Many leaders in their fields still have autoimmune flares and have not put their own autoimmunity into remission.)
Up until his creation of this new supplement, Dr. Kresser likely took his own advice, eating 12 to 16 ounces of oily fish a week, or supplementing with one teaspoon of Rosita’s (toxic) cod liver oil daily. (To explore the danger of taking cod liver oil specifically, I recommend this video.)
Interestingly, Chris Kresser has written extensively about certain dangers of fish oils, but he limits his observations, obviously — because now he’s out with his own version!
In what testing are pro-fish oil beliefs based?
In 2021, a cardiologist examined this question and found that the studies performed to determine if fish oil was healthy were too dubious to ever recommend them again to any patient:
- In one study, two groups took oils: one group took fish oil and seemed to show better health than the placebo group, but it turned out that the second group was taking mineral/corn oil pills. Of course, we would expect fish oils to hurt the body less than an inflammatory vegetable oil that is man-made and toxic.
- Another study showed that fish oils are actually more likely to cause dangerous heart arrhythmias: “People receiving fish oil had a significantly greater risk of atrial fibrillation, which can lead to a higher risk of stroke.”
- A third study showed that lower doses of fish oil, while less likely to cause danger to the heart, still did nothing to prevent heart disease.
This doctor, realizing that fish oils can’t claim to “do no harm”, steered clear of recommending them. Instead he focused on diet, exercise and weight loss. His work led to a 40 percent lower LDL level on average for his patients.
The fish oil dose of 3 grams a day or higher seems to be particularly dangerous, as seen in several studies. But if 3 grams daily is dangerous, I’m sure I don’t want to take the recommended (by Chris Kresser) 1 gram daily.
The study reads, “Risk of cardiac death was higher among subjects advised to take oily fish than among those not so advised … and even greater for sudden cardiac death … The excess risk was largely located among the subgroup given fish oil capsules.”
Risk of heart disease and death increase with just the increased consumption of fatty fish, but even more so with fish oil supplementation!
As for me and my house, we will not be increasing our consumption of fatty fish or taking fish oil pills!
Why Fish Oil is BAD for You: Omega-3s and omega-6s
Generally, it is understood in the medical community that the human diet should have a good balance of essential fatty acids: anywhere from 1:1 to 4:1, omega-6 to omega-3 fats, depending on the study.
Too many omega-6 fatty acids cause inflammation. These fats fall under an umbrella term, PUFAs, or polyunsaturad fatty acids, that also includes omega-3s.
But, even fish oil is a polyunsaturated fat, an omega-3 PUFA.
Because the American diet already includes so many PUFAs, better sources of fat are monounsaturated fats (omega-9s [like from olive oil]) and limited saturated fats from pastured animals.
Fish oil pills are pushed specifically to lower triglycerides, as high triglycerides can be a marker for heart disease.
Stop taking omega-3 pills and change your diet
But, there’s a better way!
It’s not what most people want to hear, but it’s true: We need to decrease sources of omega-6 fats instead of adding omega-3 fish oils to a diet already high in PUFAs.
Many people don’t even realize their diets are high in PUFAs. So where are those fats coming from?
- Almost ALL restaurant food is made with vegetable oil. This includes restaurants you think are healthy.
- Store bought prepared foods use almost exclusively vegetable oil (from rotisserie chickens to freezer aisle foods to packaged sauces to cookies, cereals, breads, plant-based milks, health food bars, shake mixes and more — almost all prepared foods, including those sold at natural food stores).
We’re often told it’s the ratio of omega 3 to 6 fats that matters, and most of us eat too many omega-6s. So it stands to reason, we can just add omega-3s, right?
Omega-3s from beef?!
No, it’s not that easy. We can now see from studies that we’re not meant to drink huge amounts of oil from fish (go figure!).
Instead, we’re meant to treat our bodies with respect and to buy meat from animals that were raised with respect. Yes, that’s right: Animals raised on green grass their whole lives, the way animals were meant to be raised, produce meat with fat that’s good for us (in moderation).
This still does not mean we should eat extra animal fat for improved health.
One important but surprising take away here is: If you reduce overall fat intake, processed foods and eat a truly balanced diet, you don’t have to worry about your omega-6 to omega-3 fatty acid balance! You can just eat, and enjoy life!
Sourcing of meat matters
If we buy grass-finished beef (raised on pasture until it’s slaughtered), it is naturally high in omega-3 fatty acids that help to balance out the omega-6 fats in our diet.
And, we need to decrease (or ideally eliminate) consumption of vegetable oils, processed foods and reduce other sources of omega-6s.
Less fat overall, grass-finished beef and no processed foods (including vegetable oils) = our bodies get the whole foods they were meant to receive in the right ratio to one another.
Slow homemade food
That’s why the countries with the longest life spans and the least disease aren’t countries like America. We buy more supplements and eat more processed foods.
We need to do just the opposite: Take longer to enjoy homemade foods, use olive oil, avoid super foods, and reduce the supplements we take.
And: Eat ruminant animals — those that graze on grass their whole lives, for the right fatty acids in our diet. This approach to nutrition and health also blesses the health of the planet (more than any battery operated car or plant-based diet).
Why Fish Oil is BAD for You: All fats can lead to bile duct problems or fatty liver
It’s the new health epidemic in the U.S. Affecting not only junk-food addicts, but also those who think eating good fats in high volumes is healthy: Fatty Liver Disease is nonalcoholic fatty liver disease, a condition in which too much fat is stored in the liver cells.
Yes, even fish oils poison the liver. <– This study concluded, “Fish oil diet exacerbates the hepatic injury and prevents cell proliferation-regeneration in normal and injured liver cells. Suppression of tissue regeneration by fish oil may lead to progression of the hepatic injury”.
A small amount of fat in one’s diet is delicious and just part of being alive. We can’t and shouldn’t avoid fat entirely.
But to supplement added fat is to encourage our bodies to absorb or re-absorb toxins; this goes for fish oils, too.
How the liver works
The liver creates bile to aid digestion and absorb toxins. We want proper bile flow. Bile in the intestines is like a trash truck on the road, taking out toxins.
But when we eat excess fat, the body stores it (and the toxins consumed with it) in the liver.
Eating extra fat makes our bodies re-absorb fat and toxic bile, instead of allowing that bile to exit the body with our feces.
Many of us have not been diagnosed with Fatty Liver Disease, which is why it is also called Silent Liver Disease (although this diagnosis is increasing). But mounting evidence shows backed up bile ducts and decreased bile flow (called cholestasis [which I’ve heard referred to as “leaky liver”]), are common.
Many of our symptoms lead to this finding, but most of us are ignorant that it’s our livers that need detoxing (and the problem is complex).
Reduce fat intake
Add to that re-absorbed bile, which includes bile’s toxins in our bloodstream, and we have a problem that is solved in part by reducing fats — which push toxins back into the liver.
It’s simple to do: Reduce fats and oils in our diet.
Just because something claims to be “anti-inflammatory” doesn’t mean it is.
Said plainly, fish oils are pro-inflammatory. They are more likely to cause heart disease, backed up bile ducts and toxicity in the liver.
This isn’t like the 1980s trend (that I lived through), to eat a nonfat diet. It just means to reduce fats, and certainly don’t add them in, thinking they’re healthy.
And … reduce fructose
A bit off topic, but I can’t pass by the topic of fatty liver without mentioning it. Many people steer toward sweets, and more so when they try to reduce fat. It’s like we’ve GOT to have something that’s not good for us.
So, just to present all the related facts: The body converts excess fructose (even honey) into fat and stores it in the liver. Fructose, like fat, verifiably leads to Fatty Liver Disease.
We can’t escape that eating healthy means reducing overall fats and sweeteners.
Why Fish Oil is BAD for You: More fish oil dangers
- Toxic levels of vitamin A found in fish oils for pets leads to recall. New evidence shows us: vitamin A is stored in the liver and treated like a toxin, as the body detoxes it when given the chance (a low vitamin A diet). Perhaps we should be asking if all fish oil is too high in this “vitamin”.
- Many humans experience signs of vitamin A toxicity from taking fish oil pills. Symptoms may be as small as having chronically dry or chapped lips.
- Note: Amounts vary and listing vitamin A content is no longer required (scary), but about 1000 mcg of vitamin A is reported in some brands of fish oil, per serving.
- All fish oils are high in aldehydes. Aldehydes are toxic chemicals that slow down our detox pathways. We want to reduce exposure to aldehydes as much as possible.
- Fish oils are highly fragile and vulnerable to oxidative degeneration, thus disease-causing when exposed to heat, light or air. (Note: Mono-unsaturated fats are less susceptible, and saturated fats, with their double bonds, are well protected against oxidation.)
- All animal fats hold the toxins of the animal from which they came. Don’t expose yourself to concentrated toxins. Toxins are stored in the liver and fat to protect humans and animals from them.
- Remember that supplements are a for-profit multi-billion dollar industry. To make money for someone else, we are sold products and told they’re good for us.
Are fish oils healthy
At their very best, studies show that fish oils are inconclusive in their effects on a variety of health conditions.
When looked at honestly, studies show the many dangers of fish oils:
- heart disease
- liver disease
- the ill effects of both of these conditions (including skin and mental health issues)
- increased risk of stroke
- sudden death
- exposure to high levels of vitamin A, aldehydes, oxidation and animal toxins
Ask yourself: What foods are naturally gleaned from a truly ancestral diet, balanced by the seasons, scarcity and availability? It looks nothing like the grain-free “eat the rainbow” diet pushed right now.
Similarly, what foods are considered good foods in the Bible?: Meat, not extra-oily fish, bread and some grains, beans, fruit (including cucumbers) and small amounts of condiments. (If you eat a grain-free and legume-free diet, I did, too. For about 10 years, I never thought I’d be able to eat grains or beans again. But one good change leads to another, which over time creates more freedom.)
While this may not be relevant for all of you: The Bible even talks more than once about avoiding extra fat (remember that’s where toxins are stored): “This is a lasting ordinance for the generations to come, wherever you live: You must not eat any fat or any blood.” (Leviticus 3:17)
Other than olive oil, fat is a modern food.
The main supplements most of us should be taking, in my opinion, are those removed from a modern diet due to mistreatment of the environment, such as well-chosen minerals.
No human lacks fish oil.