Why Fish Oil is Dangerous

You can’t effectively squeeze lemon on a fish oil capsule.

Can You Tell It’s Rancid?

Most fresh fish is odorless. It shocks me whenever restaurants garnish rancid fish with a lemon wedge for diners to squeeze and neutralize malodor. It bewilders me when fish lovers say the only downside is the stench that lingers after cooking it. With your apparent interest in this topic, does it also shock you? Who is the worst offender, the chefs who serve fetid fish or the patrons who happily citrusize and gulp it down? What other fetid meats do consume?

Sure, citrus fruits may be used as part of a recipe, if you like, but not to mask unpleasant smells and rot. When I was a pescatarian, nearly 80% of my restaurant-ordered salmon entrees were rejected based on the odor.

Because of price, convenience, preference, or potential mercury contamination, most people do not consume enough fresh fish to receive all the essential nutrients. Therefore, they resort to less expensive and more convenient supplements like fish oil. Fish oil is commonly used in Vietnamese, Thai, and other Asian dishes.

Benefits of Fish Oil

Many health benefits are attributed to fish oil. It aids in the treatment of heart diseases, high cholesterol, depression, anxiety, ADHD, low immunity, cancer, diabetes, inflammation, arthritis, IBD, AIDS, Alzheimer's disease, eye disorders, macular degeneration, and ulcers. It also provides nutrition for weight loss, pregnancy, fertility, and skin care (particularly for conditions such as psoriasis and acne).^[1,2] That’s quite a resumé!

The presence of omega-3 essential fatty acids like Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA) account for most health benefits. Other useful essential fatty acids include Alpha-linolenic acid (ALA) and Gamma-linolenic acid (GLA).^[2]

Sources of omega-3 fatty acids for vegetarians include walnuts, flax seeds, soybeans, tofu, flax seed oil, and eggs. However, these generally have much lower assimilated concentration of this beneficial nutrient as fresh fish or fish oil. Get in the habit of cooking with flax seed oil instead of butter, olive, or other vegetable oils to increase omega-3 intake.

Fish Oil Capsules

Fish oil supplements are usually made from mackerel, herring, tuna, halibut, salmon, cod liver, whale blubber, or seal blubber. The supplements often contain small amounts of vitamin E to prevent spoilage.

Licensed acupuncturist, Chris Kresser indicates, “Omega-3 fatty acids are highly vulnerable to oxidative damage. When fat particles oxidize, they break down into smaller compounds, like malondialdehyde (MDA), that are dangerous because they damage proteins, DNA, and other important cellular structures.

“There is no evidence that people other than those with arrhythmia and chronic heart failure benefit from taking fish oil or that doses higher than one gram of omega-3 fatty acids per day provide any benefit over smaller doses.” Kressler recommends eating fatty fish a couple times per week, and taking cod liver oil daily.^[3]

Potential Fish Oil Dangers

The National Academy of Medicine sets the daily adequate intake (AI) of omega-3 fatty acids as 1.6 grams for adult men and 1.1 grams for adult women. Standard supplements typically contain about 1 gram of fish oil, with 120 milligrams of EPA and 120 milligrams of DHA—the two types of omega-3 fatty acids.^[4]

In high doses (overdose levels), fish oil supplements can be toxic. Get emergency help if you have symptoms of an allergic reaction, including hives, difficulty breathing, swelling of throat, tongue, lips or face. Discontinue taking fish oil if you experience irregular heartbeats, flu-like symptoms or chest pain.

Side Effects From Hyperdoses of Fish Oil^[5]
Increased risk of bleeding	If taking extremely large amounts, hemorrhagic stroke, blood in the urine and nosebleeds may be manifested.
Vitamin toxicity	Fish liver and fish liver oils (like cod liver oil) contain high amounts of vitamins D and A. Fish oil supplements, however, do not contain too much vitamin A or D. Also, vitamin E is sometimes added.
Reduction in blood pressure	A Small reduction in blood pressure corresponds to increased omega-3 intake, so people who take blood pressure-lowering medications or those with low blood pressure should be careful.
Slight increases in fasting blood glucose for type-2 diabetics	It seems, however, that scientific evidence doesn’t show any long-term side effects on diabetics from taking fish oil.
5 to 10% LDL increase	Studies show that LDL (bad cholesterol) levels increase slightly as you take more fish oil.
Upper respiratory tract swelling	This side effect of fish oil has only been found in some patients.
Allergic reactions	Skin rashes, itching, hives, swelling, difficulty breathing, swelling of the throat usually only happen in people who have fish allergies.
Stomach and gastrointestinal upset	Some people get diarrhea from fish oil and it only gets worse for them with higher amounts. Some people also claim fish oil side effects like heartburn, bad breath, fishy aftertaste, burping, stomach pain and bloating, acid reflux, and indigestion. These are the most common side effects of fish oil omega-3.
Too much DHA in infants and small children	Fish oil supplements may not be suitable for infants and small children because the brain doesn’t need EPA and in trying to get DHA, it gets too much EPA.

Okay, you say. Keep fish oil away from small children. If you have a fish allergy, don’t take fish oil capsules. Even without a known allergy, avoid overdosing on fish oil to reap all the benefits. Does that sum it up?

Most Fish Oil Is Rancid

Many fish oil products in the market sit on shelves for three years or more. Therefore, they are already rancid before consumers get them home. Likely you have heard the locution, “Repetition is the mother of retention.” Well, if you have a tendency to “repeat” after ingesting fish oil capsules, retention of the bottle is ill-advised.

Light, heat and air cause oxidation, affecting capsule longevity. The more fat is unsaturated, the more likely it is to go rancid. The EPA and DHA in fish oil are both highly unsaturated fatty components. When damaged, the fats in fish oil oxidize and become lipid peroxides, which cause free-radical damage and, hence diseases.^[6]

Norway is a leading nation in high-quality fish oil manufacturing that supplies up to 40 percent of the world’s fish oil. A Norwegian clinical study showed that 95 percent of 113 over-the-counter fish oil capsules were so rancid that they did not meet official quality standards.

If you burp up fish oil all day long you should change to a different brand. The oil is rancid.

“For years we have been telling people to open up their capsules—taste and smell what they are swallowing,” said Dr. Bo Martinsen, a native Norwegian and co-founder of Omega 3 Innovations in Venice, Florida, USA. “Now Norwegian researchers are echoing these words and adding, ‘If you burp up fish oil all day long you should change to a different brand. The oil is rancid.’”^[7]

Eat or Not?

High-quality fish oil capsules are viable supplements in regular small doses, provided they are not among the 95 percent of rancid capsules on shelves. Save your receipt whenever purchasing fish oil capsules. Before ingesting, pierce or cut one open and smell for rancidness. If it’s bad, don’t just squeeze a lemon on it; return it for a refund or throw it out.

During the manufacturing process, deodorization is performed by injecting water vapor into fish oil. In this way, volatiles that give the fishy smell and taste to fish oil are removed by evaporation. After the deodorization step, the oil is cooled, and stabilized by the addition of antioxidants. The antioxidant blend is a mix of natural products consisting of tocopherols and other food-grade antioxidants.^[8]

If you are a vegan, or vegetarian, or if high-quality fish oil supplements are unavailable, include walnuts, flax seeds, soybeans, tofu, flax seed oil, or eggs in your weekly diet. Microalgae oil is a vegetarian alternative to fish oil. Supplements produced from microalgae oil provide a balance of omega-3 fatty acids similar to fish oil, with a lower risk of pollutant exposure.

So what’s the bottom line? Omega-3 fatty acids provide numerous benefits and may even be prescribed by physicians to treat various health conditions. Fresh fish is the best source of omega-3 fatty acids. Because of price, convenience, and preference, most people do not consume enough fish nutrients. If you decide to take supplements, purchase a reputable Norwegian brand and pierce for a smell test before consuming. Get essential omega-3 fatty acids one way or another for good health.

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