Omega-3 Side Effects: How Much Is Too Much? - Dr. Axe

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Omega-3 Side Effects & What They Mean


Omega 3 side effects

Do omega-3 supplements have side effects? Can taking omega-3 be harmful? It is possible to experience unwanted and even alarming omega-3 side effects (mainly, when you take too much). So why do some people take omega-3 fatty acids in the first place?

The potential benefits of omega 3s are plentiful and well-studied. We know that there are omega 3 benefits for women and children, omega-3 benefits for men, omega-3 benefits for skin, omega-3 benefits for hair… the list goes on and on.

Omega-3 fatty acids cannot be made by the human body. This is why many people turn to supplements, especially if they have a hard time getting enough omega-3s in their diets. Some top positive health effects of omega-3 fatty acids include lower triglyceride and cholesterol levels, decreased blood pressure, reduced plaque buildup in the arteries, and a lesser risk of heart attack, abnormal heart rhythm and stroke.

As you can see, there is a lot to love about these essential fatty acids, but it’s also important to be aware of potential side effects and how you can avoid them. I’m about to answer some very key questions including:

  • How much omega-3 should you have a day?
  • What are the negative effects of fish oil?
  • How can I reap the benefits of omega-3s while avoiding side effects?

Top Omega-3 Side Effects

Possible side effects of omega-3 can include both negative and positive side effects.

Some of the top positive omega-3 side effects include:

  • Improved heart health
  • Mental health support
  • Reduced inflammation
  • Autoimmune disease management
  • Potentially lower cancer risk
  • Bone and joint support
  • Improved sleep
  • PMS symptoms aid
  • Anti-aging
  • And more

However, there are also some negative omega-3 side effects, which tend to occur when getting too much of this fatty acid, including the following:

1.  Fishy Taste or Fishy Breath

Omega-3 fatty acids side effects can vary depending on the source of omega-3s in the supplement you take. If you take fish oils as your source of omega 3s, then it is possible to experience some fishy side effects.

Side effects of fish oil pills and omega-3 krill oil side effects can include a fishy aftertaste or even fish breath. This is often due to a poor-quality product that is rancid. While it’s normal for fish oil supplements to smell or even taste like fish, they ideally should not leave behind this taste and odor, but it is definitely a possible common side effect.

2. Digestive Issues

Omega-3 bad side effects can include digestive troubles, including nausea, bloating, burping, stomach upset and loose stools. These possible digestive omega-3 side effects are more likely and/or worse with higher doses of fish oil.

Omega-3 capsules side effects can also include burping. Some people find liquid fish oil supplements easier on their digestive systems. With the lack of a capsule, absorption of liquid fish oils by the body can be faster and easier.

3. Abnormal Bleeding

If you begin having nosebleeds or bleeding gums after supplementing with omega-3s, you may be experiencing abnormal bleeding. This is one of the possible side effects omega-3 supplements can cause in users.

A 2013 study reveals possible omega-3 supplements side effects can include decreased blood clotting in healthy adults taking 640 milligrams of fish oil daily. Overall, the researchers conclude that higher doses of omega-3s are a more suitable recommendation for patients with heart disease rather than healthy subjects.

The possibility of abnormal bleeding is exactly why people on blood thinners are warned not to take omega-3s without talking to their doctors first.

4. Decrease in Immune System Function

Omega-3s have impressive anti-inflammatory effects that can help a wide range of health concerns. However, high doses of fish oil may possibly lower activity of the immune system, which can decrease the body’s ability to fight off infection.

A scientific review published in 2013 found that “excess amounts of omega-3 fatty acids can alter immune function sometimes in ways that may lead to a dysfunctional immune response to a viral or bacterial infection.” This possible side effect is especially concerning for anyone with a compromised immune system as well as the elderly.

5. Vitamin A Toxicity

One of the possible omega-3 fish oil side effects, particularly of cod liver oil, is vitamin A toxicity. Cod liver oil certainly has its health benefits, but you do want to be careful that it’s a good fit for you and that you don’t take too much. Just one tablespoon of cod liver oil contains around 270 percent of most people’s daily needs for vitamin A.

Vitamin A is a fat-soluble nutrient. That means that when taking excess vitamin A, it gets stored in our bodies (mainly in the liver). Levels of vitamin A can then accumulate and sometimes lead to dangerous toxicity.

According to the National Institutes of Health, chronic intake of excess vitamin A can lead to increased intracranial pressure, dizziness, nausea, headaches, skin irritation, pain in joints and bones, coma, and even death.

How Much Is Too Much Omega-3?

Ideal amounts of omega-3s can vary from person to person depending on a number of factors, including age and health concerns. Ask your health care provider about an ideal dosage for your needs. In general, how much omega 3 per day? Taking more than three grams of fish oil each day may prevent healthy blood clotting and increase the risk of bleeding.

According to the Mayo Clinic, it is not clear if people with fish or shellfish allergies can safely take fish oil. It’s always best to talk to your health care provider before taking omega-3 supplements, especially if you have any fish/shellfish allergies.

What about Lovaza? Lovaza is a brand name of omega-3-acid ethyl esters. Common omega 3 acid ethyl esters side effects may include back pain, upset stomach, burping, skin rash, and an unusual or unpleasant taste in your mouth. Very serious side effects can include easy bleeding/bruising, black or tarry stool, or vomit that looks like coffee grounds.

It’s also important to note that fish oil can possibly interact with anticoagulant and anti-platelet drugs, herbs and supplements; blood pressure drugs, herbs and supplements; contraceptive drugs; weight loss drugs like orlistat (Xenical, Alli); and vitamin E. Talk with your healthcare provider before combining omega-3 supplements with any of these.

How to Prevent/Overcome Omega-3 Side Effects

The best way to prevent unwanted omega-3 side effects and omega 3 6 9 side effects is not to take more of a supplement than recommended by the manufacturer and/or your health care provider.

Another way to avoid unwanted side effects is to obtain these important fatty acids from high omega-3 foods on a regular basis, including wild-caught fatty fish, chia seeds, walnuts and flaxseeds. To avoid unwanted side effects of omega-3 fish oil, eating a diet rich in fatty fish like salmon and sardines is another option.

Buying a high-quality omega-3 supplement can also help lower unwanted side effects, like an unpleasant aftertaste. For example, not all fish oils are created equal. Many fish oils are very processed and can oxidize easily because omega-3 fats are polyunsaturated, have a low heat threshold and can easily go rancid. Look to purchase a fish oil in triglyceride form that also contains antioxidants to preserve them like astaxanthin or essential oils.

Risks and Side Effects

Since the body can’t make omega-3 fatty acids on its own, supplements can be a very beneficial and effective way for some people to include these important nutrients in their diets. However, it’s important that you take omega-3 supplements correctly and safely by not exceeding recommended dosages.

Too much omega-3 side effects can more commonly include a fishy aftertaste, bad breath, indigestion, nausea or loose stools. More concerning but less common omega-3 side effects can include abnormal bleeding, compromised immune function and vitamin A toxicity (cod liver oil). Most of these side effects can be avoided by not taking too high of a dosage.

To avoid unwanted omega-3 side effects in general, you should never take more of a supplement than recommended by the manufacturer/your health care provide. You should also purchase high-quality supplements that can help to avoid some unwanted side effects, such as a fishy aftertaste from fish oil supplements.

Eating a diet rich in omega-3s on a daily basis is always a great and safe way to obtain these essential fatty acids, especially if you don’t do well with omega-3 supplements. Always check with your health care provider before starting an omega-3 supplement of any kind, especially if you are pregnant, nursing, diabetic, being treated for a medical condition or currently take other medication/supplements.

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