Why Are My Fish Oil Supplements Cloudy?
You may have read about it online or even experienced it yourself: cloudy fish oil softgels. If you store your supplements in the fridge or if they’re delivered during cold weather, your softgels might appear cloudy.
Are they still safe? The simple answer: yes, your fish oil softgels are most likely perfectly fine, but seeing the cloudiness can raise some questions. We’ve got answers that’ll leave your mind at ease.
The Science Behind Cloudy Fish Oil: Simple Facts
Different Fats, Different Melting Points
Different fats have different melting points—they solidify at different temperatures. It comes down to molecular design and the difference between saturated and unsaturated fats. Polyunsaturated fatty acids (PUFAs), like omega-3 in fish oil, have a lower melting point, so they remain liquid (clear) in cooler temperatures.1 However, polysaturated fatty acids, often added to fish oil supplements in very low amounts, have a higher melting point—they begin to solidify at a slightly higher temperature than unsaturated fats,1 and when they do, you may see a “cloudiness” in your fish oil softgels.
An example of different fats melting or solidifying at different temperatures can be thought of like this: if you pull a loaf of bread from your freezer along with a frozen turkey and set them on the counter, the bread will thaw and soften before the turkey. One isn’t better or worse than the other—their makeup just warms at different rates.
Is Cloudy Fish Oil Safe? The Good News
Natural Ingredients Behaving Naturally
The good news is that some cloudiness in your fish oil supplement may be a sign of quality ingredients. Saturated fat occurs naturally in fish like anchovies—the species used in Swanson’s Omega-3 Fish Oil. Anchovies contain about 2.75 g of saturated fat per ounce.2 If you find a brand of fish oil softgels that doesn’t exhibit cloudiness below certain temperatures, you may wonder if those softgels are as pure. Stick with quality-tested fish oil supplements made by experts and featuring a little cloudiness now and then.
Cloudiness vs. Quality: What Really Matters
The real test of a fish oil supplement’s quality isn’t how clear or cloudy it is, but in the way it’s manufactured. At Swanson, we’re steadfast in our commitment to high-quality, science-backed products that undergo rigorous third-party testing for purity and potency.
Another factor in the quality of a fish oil supplement is its packaging label. The best supplements contain proper and clearly labeled levels of essential fatty acids like EPA and DHA and are cleansed of impurities.
When to Actually Worry About Your Fish Oil
When it comes to the safety and quality of fish oil supplements, there are some simple signs to tell if it’s gone rancid. A bad or sour taste or smell are generally a negative signs. If the softgels are damaged or leaking, or if the supplement has been stored for a long time contrary to the label instructions, you may want to consider discarding. Finally, always look at the expiration date on the packaging, and if that date has passed, do not consume the product.
The Best Ways to Store Your Fish Oil
Finding the “Goldilocks Zone” for Storage
Most fish oil supplements require storage in a cool, dry place—generic instructions meant to preserve the softgels against heat/melting and humidity. It’s advised to keep fish oil supplements in a temperature range of about 59-86° F.3 For a simple storage plan that keeps your supplements in what some have called the “Goldilocks” zone, where they are neither too hot nor too cold, consider a bathroom medicine cabinet or dedicated drawer in the kitchen.
Refrigeration Myths and Facts
Should you refrigerate fish oil supplements? Following label instructions for proper storage of any supplement is the best advice. For Swanson fish oil supplements, refrigeration isn’t necessary. It really comes down to your preference and the climate you’re living in. While refrigerating your supplement may slow the oxidation process, if you use your fish oil within the “use by” date, it should be perfectly fine.
Keep in mind that if your fish oil softgels are kept too cold (or freeze), this can cause them to crack or burst, which would obviously be a mess best avoided. Store your supplement in a cool, dry place away from direct sunlight and out of reach from children, and it should be just fine.
Beyond Fish Oil: Other Supplements That Get Cloudy
The Coconut Oil Connection
Vitamin D is a fat-soluble nutrient requiring fat to be present for proper absorption. Therefore, vitamin D supplements often include an oil ingredient, like coconut oil, to provide the necessary fat. Coconut oil is comprised of around 90% saturated fat.4 So, it has a higher melting and solidifying point—your vitamin D supplement with coconut oil may appear cloudy at temperatures below 76° F.
The Oil Rainbow: Understanding Different Supplement Oils
Common carrier oils used to help deliver fat-soluble nutrients in supplements include coconut, sunflower or olive oil. Each oil features either saturated or unsaturated fats (or a small mixture) and so may appear cloudy below certain temperatures. The higher the saturated fat content of an oil, the higher the temperature must be for it to remain clear. Cloudiness doesn’t typically mean poor quality or spoilage and may in fact be an indicator of purity.
Frequently Asked Questions About Cloudy Fish Oil
Is My Fish Oil Rancid if It’s Cloudy?
Probably not. You can tell if a softgel is rancid by its smell or taste—simply poke a small whole to examine. If your fish oil supplement is expired or has a bad smell or taste, discard.
Does Cloudiness Affect Potency?
Cloudy fish oil supplements can indicate higher quality, purity and potency. That’s because the omega-3 essential fatty acids in fish oil can begin to solidify and appear cloudy below certain temperatures. Lower quality supplements may not do the same if they include other ingredients. The potency of supplements is less related to appearance and more to craftsmanship, such as including pure, well-sourced fish oil and proper levels of EPA and DHA.
Making Smart Choices About Fish Oil Supplements
Beyond Appearances: What Really Matters
The best fish oil supplements are those made with high standards for purity, sourcing and rigorous third-party quality testing. These are standards which Swanson prides itself on for all its supplements. To gauge the value of a fish oil supplement, consider its essential fatty acid content. Look for efficacious doses of both EPA and DHA. Taking the quality of the supplement, its nutritional value and your own personal needs into account will help you select the best supplement.
Embracing the Cloud
Cloudy fish oil shouldn’t be a cause for alarm, as that cloudiness is indicative of the essential fatty acid content in the supplement, reflecting its quality, purity and natural ingredients. Making informed decisions on which supplements to try is important, so make sure to always consider the manufacturer, the ingredient list and any personal health goals you have. It’s also a good practice to discuss any new or changing supplements with your doctor. Check out Swanson’s powerful lineup of omega-3 options like Triple Strength Super EPA & DHA, Omega-3 Fish Oil with Vitamin D or High Concentrate Omega-3.
Looking for more information on fish oil supplements? Read Krill Oil vs. Fish Oil: Which Has More Benefits?
You be well, now.
Swanson
*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.
Sources
- Morsch, L. Lipids. Chemistry Libre Texts. Accessed June 2, 2025. Read source
- USDA. Accessed June 2, 2025. Read source
- Fish Oil Capsules. Cleveland Clinic. Accessed June 2, 2025. Read source
- Boateng L, et al. Ghana Med J. 2016 Sep;50(3):189-196. Read source
