Cod liver oil has been a staple in medicine cabinets for centuries. Once, spoonfuls of the strong-tasting liquid were forced upon children to ward off rickets; today, it has evolved into a highly refined supplement favored for its unique nutrient profile. But is it still relevant in the age of modern multivitamins?
The short answer is yes. Cod liver oil is a nutrient-dense powerhouse unlike almost any other supplement. It is one of nature’s best sources of omega-3 fatty acids, vitamin A, and vitamin D—all in one package.
Whether you are looking to support heart health, improve skin texture, boost immunity, or strengthen bones, understanding what is cod liver oil good for is the first step. In this comprehensive guide, we will explore the science-backed benefits of cod liver oil, compare cod liver oil vs fish oil, and break down proper dosage to ensure safety.
What Is Cod Liver Oil?
Cod liver oil is exactly what it sounds like: oil extracted from the liver of codfish (specifically Atlantic cod, Gadus morhua). This distinction is crucial because most standard fish oils are extracted from the flesh of oily fish like tuna, herring, anchovies, and mackerel.
Because the liver is where cod store certain fat-soluble vitamins, cod liver oil is chemically different from standard fish oil. It is a rich source of:
- Omega-3 Fatty Acids (EPA and DHA): Essential fats that fight inflammation.
- Vitamin A: Critical for eye health and immune function.
- Vitamin D: Vital for bone strength and regulating the immune system.
Is Cod Liver Oil the Same as Fish Oil?
No. While both provide omega-3s, standard fish oil contains little to no vitamins A and D unless they are synthetically added. Cod liver oil naturally contains high levels of these vitamins. This makes cod liver oil a more comprehensive supplement for immune and bone support, though it requires more careful dosing to avoid vitamin toxicity.
Traditional & Modern Use
Historically, what is cod liver oil used for centered on preventing nutritional deficiencies. In the 1800s and early 1900s, it was the primary treatment for rickets (a bone-softening disease caused by Vitamin D deficiency) in children living in Northern Europe. Today, it is used as a daily preventative supplement to reduce inflammation, lower cholesterol, and support overall longevity.
What Is Cod Liver Oil Good For?
If you ask your grandparents, they might say it’s good for “everything.” Science has since narrowed down the list, but the benefits remain impressive.
What does cod liver oil do for you? Here is a quick snapshot of its primary uses:
- Immunity: The combination of Vitamin D and A helps the body fight off infections.
- Bone Health: Vitamin D ensures calcium absorption, preventing fractures and osteoporosis.
- Brain & Heart Health: Omega-3s support cognitive function and lower triglycerides.
- Skin, Hair & Joints: Anti-inflammatory properties help reduce joint stiffness and acne.
- Eye Health: Vitamin A protects the cornea and supports night vision.
Cod Liver Oil Nutrition Facts
To understand why this oil is so potent, we need to look at its nutrient breakdown. A single teaspoon (5 ml) of high-quality cod liver oil typically contains:
- Calories: 40
- Fat: 4.5g
- Vitamin A: 850–1500 IU (approx. 90%–150% of Daily Value)
- Vitamin D: 400–1000 IU (approx. 100%–200% of Daily Value)
- Omega-3 Fatty Acids: 800–1000 mg
Does Cod Liver Oil Have Omega-3?
Yes. It contains two main types of omega-3 fatty acids:
- EPA (Eicosapentaenoic acid): Powerful anti-inflammatory effects; supports heart and mood.
- DHA (Docosahexaenoic acid): Crucial for brain development and eye health.
Does Cod Liver Oil Have Vitamin D?
Yes, and it is one of the very few food sources that do. Does cod liver oil have vitamin D naturally? Yes, although some manufacturers standardize amounts to ensure consistency. It is an excellent alternative for people living in northern climates who do not get enough sunlight to produce Vitamin D naturally.
Does Cod Liver Oil Have Vitamin A?
Yes. It is incredibly high in Vitamin A (retinol). This is excellent for skin and eyes but is also the reason you must adhere to recommended dosages. Excessive Vitamin A can accumulate in the liver and cause toxicity, a risk not present with standard fish oil.
Cod Liver Oil Benefits (Evidence-Based)
The benefits of cod liver oil span across age groups and genders. Let’s break down the specific advantages supported by research.
Cod Liver Oil Benefits for Female
Women often have unique nutritional needs regarding bone density and hormonal balance.
- Hormonal Health: The omega-3s in cod liver oil are precursors for prostaglandins, compounds that regulate hormones. This may help alleviate symptoms of PMS and menopause.
- Pregnancy Nutrients: Omega-3 DHA is critical for fetal brain development. However, pregnant women must consult a doctor before taking it. High doses of Vitamin A (retinol) can be teratogenic (harmful to the fetus).
Many doctors recommend standard fish oil over cod liver oil during pregnancy for this specific safety reason.
- Cod Liver Oil Benefits for Skin: Women often report that the high Vitamin A content helps reduce acne breakouts and smooths skin texture.
- Cod Liver Oil Benefits for Hair: The fatty acids nourish hair follicles, potentially reducing brittleness and promoting shine.
Cod Liver Oil Benefits for Male
For men, the focus often shifts to heart health and physical performance.
- Testosterone & Fertility: Vitamin D deficiency is linked to low testosterone levels. By correcting this deficiency, cod liver oil may support healthy testosterone production and sperm quality.
- Heart Health: Men are statistically at higher risk for heart disease. Omega-3s help lower blood pressure and reduce dangerous triglycerides.
- Muscle Recovery: The anti-inflammatory properties of EPA help reduce muscle soreness (DOMS) after heavy lifting or exercise.
Cod Liver Oil Benefits for Kids
Cod liver oil for kids was the original use case, and it remains relevant.
- Prevents Rickets: It ensures strong bone formation during rapid growth phases.
- Immunity: Regular intake is associated with fewer upper respiratory tract infections in children.
- Brain Development: DHA is a building block of the brain. Some studies suggest omega-3 supplementation can support focus and behavior in children with ADHD.
- Safety Note: Always use a pediatric-specific product. Adult doses contain too much Vitamin A for small bodies.
Cod Liver Oil Benefits for Skin & Hair
If you are searching for how to use cod liver oil for glowing skin, the answer is internal, not topical.
- Acne: Vitamin A regulates sebum production, preventing clogged pores.
- Eczema & Psoriasis: The anti-inflammatory action of omega-3s can calm red, itchy skin associated with these conditions.
- Hair Growth: Vitamin D plays a role in creating new hair follicles. Deficiency is often linked to alopecia (hair loss).
Cod Liver Oil Joint, Heart & Cholesterol Benefits
- Joint Health: Cod liver oil helps treat arthritis. A study in Rheumatology found that patients taking cod liver oil could reduce their daily intake of NSAIDs (painkillers) by over 30% due to reduced joint stiffness.
- Cholesterol: While it may not drastically lower LDL (“bad”) cholesterol, it significantly raises HDL (“good”) cholesterol and lowers triglycerides.
Cod Liver Oil Benefits for Liver & Digestion
- Fatty Liver: Paradoxically, eating good fats helps the liver. Omega-3s reduce liver fat and inflammation in people with Non-Alcoholic Fatty Liver Disease (NAFLD).
- Digestion: Does cod liver oil help with constipation? While not a laxative, the lubrication from the oil can mildly assist bowel movements, and reducing gut inflammation supports overall digestion.
Cod Liver Oil Benefits for Weight Loss
Cod liver oil benefits weight loss indirectly. Omega-3s improve insulin sensitivity, meaning your body processes glucose more efficiently rather than storing it as fat. Furthermore, reducing systemic inflammation is often a prerequisite for breaking through weight loss plateaus.
Cod Liver Oil Benefits According to NHS & Reddit
- NHS (UK): The NHS acknowledges cod liver oil as a source of Vitamins A and D but warns against taking it during pregnancy due to retinol risks. They emphasize it for preventing Vitamin D deficiency in winter.
- Reddit: Search “cod liver oil benefits reddit,” and you will find anecdotal reports of improved mood (alleviating winter blues), cleared cystic acne, and better joint mobility. However, users frequently complain about the taste and “fish burps.”
Cod Liver Oil vs Fish Oil — Which Is Better?
This is the most common question: is cod liver oil better than fish oil? It depends on your specific health goals.
| Feature | Cod Liver Oil | Standard Fish Oil |
| Source | Liver of Codfish | Flesh of oily fish (tuna, anchovy, etc.) |
| Omega-3 Content | Moderate | High (usually more EPA/DHA per capsule) |
| Vitamin A | High (Natural Source) | Low / None |
| Vitamin D | High (Natural Source) | Low / None |
| Best For | Immunity, Bones, Skin, Vitamin Deficiency | Heart Health, High inflammation, Heavy Omega-3 needs |
| Pregnancy Safety | Caution (Vitamin A risk) | Safer (if purified) |
Which is better fish oil or cod liver oil?
- Choose Cod Liver Oil if you want an all-in-one multivitamin that supports immunity and bones.
- Choose Fish Oil if you strictly want high doses of Omega-3s for heart health or inflammation and already get enough Vitamins A and D from other sources.
Cod Liver Oil Types & Forms
Cod Liver Oil Capsules vs Liquid
- Liquid:
- Pros: Cheaper per serving; easier to take high doses; fewer additives.
- Cons: Strong taste; shorter shelf life (oxidizes faster once opened).
- Capsules:
- Pros: Tasteless; convenient; travel-friendly.
- Cons: You often need to take 3–6 pills to match the dosage of one teaspoon of liquid.
Fermented Cod Liver Oil
Fermented cod liver oil is produced using a traditional method where livers are fermented to extract the oil rather than being heated or chemically treated.
- Claim: Proponents argue it preserves more nutrients and active enzymes.
- Controversy: Critics argue it may be prone to rancidity. It has a much stronger, more pungent flavor than processed oils.
Best Cod Liver Oil Brands
When looking for the best cod liver oil, purity is paramount. The liver filters toxins, so you want oil from fish caught in clean waters (like the Arctic or Norway) and molecularly distilled to remove mercury and PCBs.
1. Rosita Extra Virgin Cod Liver Oil
- Type: Raw, fresh (not fermented, not heat-treated).
- Why it’s great: Sourced from wild-caught cod in Norway. It retains the natural spectrum of vitamins without synthetic additives.
- Best for: Purists seeking the most natural option.
2. Carlson Cod Liver Oil
- Type: Processed (purified) liquid and gels.
- Why it’s great: Consistently rated high for taste (award-winning lemon flavor) and freshness. High Omega-3 content.
- Best for: Beginners who are afraid of the fishy taste.
3. Nordic Naturals Arctic Cod Liver Oil
- Type: Triglyceride form (better absorption).
- Why it’s great: “Gold Standard” for purity testing. Made from 100% wild Arctic cod (no other fish oils used as filler).
- Best for: Overall quality and reliability.
4. Seven Seas Cod Liver Oil
- Type: Mass market, widely available.
- Why it’s great: Affordable and accessible, a household name in the UK/Europe.
- Best for: Budget-conscious buyers.
5. Green Pasture Fermented Cod Liver Oil
- Type: Fermented.
- Why it’s great: A favorite in the Paleo and Weston A. Price communities.
- Best for: Those seeking traditional fermentation benefits.
How to Take Cod Liver Oil Correctly
How Much Cod Liver Oil Per Day?
Dosage varies by age and product concentration, but general guidelines suggest:
- Adults: 1 teaspoon (5ml) or equivalent capsules daily.
- Children: 1/2 teaspoon (2.5ml).
- Upper Limits: Do not exceed doses that provide more than 10,000 IU of Vitamin A daily over long periods.
How Many Cod Liver Oil Capsules Per Day?
This depends entirely on the size of the softgel.
- Standard 1000mg softgels: Usually 1 to 2 capsules daily.
- Smaller pearls: May require 3 to 6 capsules.
- Always read the label.
How to Take Cod Liver Oil
- With Food: Always take it with a meal containing fat to maximize absorption.
- Flavor Hacks: If taking liquid, mix it into a shot of orange juice or a smoothie to mask the taste.
- What does cod liver oil taste like? Pure, unflavored oil tastes mildly fishy. Flavored versions (lemon, orange) are significantly more palatable and barely taste like fish.
Can I Take Vitamin D and Cod Liver Oil Together?
Caution is needed. Since cod liver oil already contains Vitamin D, adding a separate Vitamin D supplement could lead to excessive intake (hypercalcemia).
- Check the label: If your oil provides 100% of your daily Vitamin D, you likely do not need a separate pill unless advised by a doctor for severe deficiency.
Cod Liver Oil Side Effects & Risks
While natural, cod liver oil is potent. Cod liver oil benefits and side effects must be weighed.
Common Side Effects
- Digestive Issues: Belching (“fish burps”), heartburn, nausea, and loose stools are the most common complaints.
- Bad Breath: Can leave a lingering fishy taste.
Cod Liver Oil Side Effects on Kidney
High doses of Vitamin D (found in the oil) increase calcium absorption. Over time, excessive calcium can form kidney stones or cause calcification in the kidneys. People with existing kidney disease should consult a nephrologist before taking supplements high in Vitamin A or D.
Who Should Not Take Cod Liver Oil?
- Pregnant Women: Unless approved by a doctor (due to Vitamin A risks).
- People on Blood Thinners: Omega-3s have a mild blood-thinning effect. Taking them with Warfarin or Aspirin can increase bleeding risk.
- Upcoming Surgery Patients: Stop taking it 2 weeks before surgery to prevent bleeding complications.
Benefits and Risks of Daily Use
What happens if I take cod liver oil every day?
- Positive: Improved skin, fewer colds, better joint mobility.
- Negative (if overdosed): Vitamin A toxicity (hair loss, liver damage, bone pain).
- Verdict: Safe for daily use if you stick to the recommended dosage (approx. 1 tsp).
Where to Buy Cod Liver Oil
You can find where to buy cod liver oil easily:
- Pharmacies (CVS, Walgreens, Boots): Carry standard brands like Nature’s Bounty or Seven Seas.
- Online Marketplaces (Amazon, iHerb): Best for comparing prices and reading reviews.
- Brand Websites: Best for buying premium, fresh oils like Rosita or Nordic Naturals directly to ensure they haven’t been sitting in a hot warehouse.
Frequently Asked Questions (FAQ)
Is cod liver oil good for you?
Yes. It is a dense source of Omega-3s, Vitamin A, and Vitamin D, supporting heart, bone, and immune health.
Does cod liver oil have vitamin D?
Yes. It is one of the best natural dietary sources of Vitamin D, often containing 400–1000 IU per tablespoon.
Is cod liver oil the same as fish oil?
No. Cod liver oil comes from the liver of cod and contains Vitamins A and D. Fish oil comes from the flesh of oily fish and usually only contains Omega-3s.
Which is better fish oil or cod liver oil?
Cod liver oil is better for immunity and bone health. Fish oil is better if you need very high doses of Omega-3s without the risk of Vitamin A toxicity.
How much cod liver oil should I take daily?
The standard dose is 1 teaspoon (5ml) or 1-2 capsules daily. Do not exceed this without medical supervision.
Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new supplement, especially if you are pregnant, nursing, or taking medication.
Authoritative References
1. On Cod Liver Oil Reducing NSAID Use (Joint Health)
- Patients taking cod liver oil were able to reduce their daily requirement of NSAIDs (painkillers) by over 30% due to reduced joint stiffness. Galarraga, B., et al. (2008). “Cod liver oil (n-3 fatty acids) as a non-steroidal anti-inflammatory drug sparing agent in rheumatoid arthritis.” Rheumatology.
2. On Pregnancy Safety & Vitamin A Warning
- Pregnant women should avoid cod liver oil because high levels of Vitamin A (retinol) can harm the fetus. National Health Service (NHS), “Vitamins, supplements and nutrition in pregnancy.”
3. On Vitamin A Toxicity & Dosage Limits
- Excessive Vitamin A (retinol) from supplements like cod liver oil can lead to toxicity, liver damage, and bone pain. National Institutes of Health (NIH) Office of Dietary Supplements, “Vitamin A and Carotenoids.”
4. On Heart Health (Omega-3s)
- Marine Omega-3s (EPA/DHA) are linked to lower triglycerides and reduced risk of cardiovascular events. National Institutes of Health (NIH) National Center for Complementary and Integrative Health, “Omega-3 Fatty Acids: What You Need To Know.”
5. On Nutrient Profile (USDA Data)
- Cod liver oil is a dense source of Vitamins A and D compared to standard fish oil. USDA FoodData Central, “Fish oil, cod liver.”
6. On Historical Use for Rickets
Cod liver oil was historically the primary treatment for rickets before Vitamin D fortification became common. Rajakumar, K. (2003).“Vitamin D, Cod-Liver Oil, Sunlight, and Rickets: A Historical Perspective.” Pediatrics.
