Guide to Cod Liver Oil Side Effects and How to Avoid Them

bottles of cod liver oils in fridge

Cod liver oil is a popular fish oil due to its combination of healthy fats and vitamins, but can you get side effects from it?

Cod liver oil contains the omega 3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and it’s also a natural source of vitamin A and vitamin D.

Generally, these types of nutrients will not cause you any harm when ingested.

Omega 3 fatty acids have been shown to reduce inflammation and lower your risk for heart disease, whereas vitamins D and A can help regulate a number of bodily functions.

Learning to use these nutritional products properly and safely can greatly lower your risk so you can enjoy all the benefits they offer you.

The most common cod liver oil side effects may include:

  • Fishy breath
  • Upset stomach
  • Exposure to unwanted contaminants
  • Allergic reactions
  • Increased risk for bleeding
  • Over exposure to Vitamin A & D

Below we’ll take a closer look at the side effects and how you can avoid them….

List of the Most Common Cod Liver Oil Side Effects

Most people will can use cod liver oil without any problems. The following side effects may occur in some individuals:

  • Fishy breath – this may be caused by using poor quality or rancid cod liver oil products. You may be able to avoid this side effect by using enteric-coated or an emulsified fish oil product like Twin Lab Cod Liver Oil.

  • Upset Stomach & Digestion – you may experience fishy burps, indigestion, gas or diarrhea if you take too much cod liver oil. Research on a variety of different fish oil dosages and products have conclude that these are some of the side effects when taking fish oils.

    You can eliminate or reduce these side effects by taking only small amounts of cod liver oil to enhance digestion and taking with food. You may have to stop taking this supplement completely if these symptoms continue.

  • Possible exposure to contaminants – you may be exposed to mercury in fish oils, PCB’s, dioxins, furans and other contaminants if you do not use a highly-purified fish oil product. Make sure your cod liver oil has been tested to ensure it doesn’t contain harmful levels of contaminants.

  • Allergic reactions – if you’re allergic to fish or fish proteins, you may be allergic to cod liver oil. Many high quality fish oils have the fish proteins removed during processing to optimize the omega 3 concentrations.

    You may have to research the processing method used to make the cod liver oil to determine if they have removed these allergic proteins from your product. Not all supplement companies follow the same manufacturing process so you may need to be aware of this.

How to Avoid Cod Liver Oil Side Effects

While chances are slim you’ll experience any side effects, there are some factors you should know about taking cod liver oil:

  • You should consult with your doctor if you’re taking anticoagulant drugs such as Coumadin or Heparin.

    Studies show fish oils may reduce your risk for blood clots and may affect your bleeding time. This may be an important factor to consider if you’ve been diagnosed with any type of bleeding disorder.

  • Monitor your Vitamin A and D intake when taking cod liver oil.

    Vitamins A and D are fat-soluble; any extra your body can’t use is absorbed by your fat cells.

    If you’re getting plenty of sunshine (and also taking a multivitamin with Vitamin D) you should have your Vitamin D levels checked by your doctor before taking cod liver oil to ensure you don’t get too much vitamin D.

    This is particularly important if you have a disease such as sarcoidosis, which may make you sensitive to excess Vitamin D.

  • Try to use a pharmaceutical-grade fish oil to ensure you’re using a high quality product. Using a poor quality cod liver oil could cause fishy burps, upset stomach and even diarrhea. I prefer to use a product that is manufactured by a reputable company that specializes in making fish oils to reduce the risk for any side effects.

  • Make sure to read our Guide to the Best Cod Liver Oils for helpful tips to choosing the best products.

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