Cod Liver Oil: Benefits, Dosage, vs. Fish Oil & Side Effects

Dr. Josh Axe Vitamin Advisor · 4–5 questions

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Cod liver oil is the oil from the livers of cod, and a single teaspoon carries three nutrients most people take separately: the omega-3 fats EPA and DHA, vitamin D and vitamin A. USDA lists a teaspoon at 41 calories, with 806 milligrams of EPA and DHA, 450 IU of vitamin D and 1,350 micrograms of vitamin A.1

I put the plate before the capsule: even though fish oil supplements can be beneficial, wild-caught fish is always going to win.2 I eat a lot of salmon, so I don't take fish oil every day, but on every day I don't eat wild-caught fish, I take a wild-caught cod liver oil or another high-quality fish oil.7

Researchers have tested cod liver oil in pregnancy, in rheumatoid arthritis (as a blend with fish oil) and in a winter-long randomized trial of 34,601 Norwegian adults, which showed what a daily spoonful does for your omega-3 and vitamin D levels.

Did you know?

• In several countries, cod liver oil is traditionally taken through the fall and winter months to protect against low vitamin D.8

• In the Norwegian Women and Cancer Study, 44.7% of the women took cod liver oil.9

• Norway has cut the vitamin A in its commercial cod liver oil by 75%.8

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What is cod liver oil?

On my show, I've called cod liver oil the classic: a more food-based, typically less processed form of fish oil that also carries vitamin A and vitamin D along with the omegas.11 Regular fish oil comes from the bodies of fatty fish and carries little of either vitamin, as the comparison below shows.12

Cod is a fish with fins and scales, and my rule for fish is to choose wild, ocean-caught fish with fins and scales.13 That standard goes back to Leviticus 11:9: "These shall ye eat of all that are in the waters: whatsoever hath fins and scales in the waters, in the seas, and in the rivers, them shall ye eat."14 I list cod liver oil with cold-water fish such as salmon, sardines, herring and mackerel as concentrated sources of omega-3s.13

A short history of cod liver oil

Cod liver oil made its name against rickets, the bone-softening disease of vitamin D deficiency. Rickets was common in 17th-century England, where the physician Francis Glisson described it in detail in 1650, and at the turn of the 20th century it was rampant among poor children in the industrial, polluted cities of the northern United States.15 Its cause stayed a mystery until the 1920s. Animal experiments, the long traditional use of cod liver oil and the link between rickets and too little sunshine all helped researchers find it. By the 1930s, they had discovered vitamin D and shown how cod liver oil prevents rickets, which made it possible to treat the disease and wipe it out in the United States.15

Cod liver oil nutrition facts

Fish oil, cod liver: USDA FoodData Central, FDC ID 173577 (SR Legacy). Per-serving values are calculated from the per-100-gram values; % Daily Value uses FDA label reference values.116

Cod liver oil carries more DHA than EPA, 495 mg against 311 mg per teaspoon, plus 42 mg of DPA, a third long-chain omega-3.1 A tablespoon holds 4,080 mcg of vitamin A, which is above the adult upper limit on its own, so the teaspoon is the practical serving.16

How much vitamin A is in your bottle?

USDA's record comes from older analyses, and real oils differ: across the four below, vitamin A ranges more than fivefold. Norway's formula before 1999 carried 1,000 mcg per 5 mL,17 the oil in a Norwegian pregnancy trial published in 2003 carried 585 mcg per 5 mL (117 mcg per mL),18 and the oil in a Norwegian winter trial in 2020-21 carried 250 mcg per 5 mL.3

My Hypothyroidism Protocol doses cod liver oil per label.19 Before you decide how much to take, read two numbers on the back of the bottle: the EPA plus DHA per serving and the vitamin A per serving. The how-much section below does the math.

What is cod liver oil good for?

How does cod liver oil work in your body?

Cod liver oil works through the omega-3s, vitamin D and vitamin A it supplies. The steps below follow its omega-3s from the spoon into your cells, where they help your body bring inflammation to a close.

Cod liver oil benefits

Ranked by the evidence, cod liver oil's benefits start with omega-3 levels and vitamin D, then triglycerides, rheumatoid arthritis, pregnancy, inflammation and mood.

Cod liver oil benefits for women

Fish comes first in pregnancy. The FDA and EPA advise pregnant and breastfeeding women to eat 8 to 12 ounces of low-mercury seafood a week, 2 to 3 servings from their Best Choices list,37 and our guide to the fish you should never eat names the few to skip.

Omega-3s in pregnancy have a strong record. In a Cochrane review of 70 randomized trials with 19,927 women, omega-3s from supplements or food lowered preterm birth before 37 weeks from 13.4% to 11.9% (26 trials, 10,304 women) and early preterm birth before 34 weeks from 4.6% to 2.7% (9 trials, 5,204 women), both rated high-quality evidence; pregnancies running past 42 weeks rose from 1.6% to 2.6%.21

Cod liver oil itself was tested in Oslo. Pregnant women took 10 mL of cod liver oil or corn oil a day from week 18 of pregnancy until 3 months after birth, and neither the women nor the researchers knew who got what. Of 590 women who enrolled, 84 of their children completed testing at age 4, and those whose mothers took cod liver oil scored 106.4 on a mental-processing test, against 102.3 in the corn oil group; the scores tracked with how much DHA the mothers took in.18 At age 7, scores no longer differed between the 82 children in the cod liver oil group and the 61 in the corn oil group.27 One author worked for the oil's maker, and the daily 10 mL carried 1,170 mcg of vitamin A.18

Through perimenopause and menopause, my Perimenopause & Menopause protocol calls omega-3s the brain and vessel fat: they're anti-inflammatory and support the brain's use of glucose and the flexibility of your arteries as estrogen's protection fades, at 2 to 3 grams of EPA and DHA a day with food. It pairs vitamin D3 with K2 to support your bones, because estrogen helped activate vitamin D.36 Our guide to the best foods for bone health covers the rest of the plate.

For the rest of a pregnancy plan, see our pregnancy diet and prenatal vitamins guides.

Cod liver oil vs. fish oil: what's the difference?

Per teaspoon (4.5 g). Source: USDA FoodData Central, SR Legacy: fish oil, cod liver (FDC ID 173577) and fish oil, sardine (FDC ID 173578). Per-teaspoon values are calculated from the per-100-gram values.112

Both start in the fish as natural triglyceride oils, the form your body absorbs well, and both are good sources of EPA and DHA.10 No trial has compared the two on a health outcome; one 2-week study measured blood levels.10 What sets cod liver oil apart is its vitamins. That's why it suits a daily teaspoon, and why, for a higher omega-3 dose, an oil near the USDA figure pairs well with fish oil. The how-much section shows the math. Algae oil is another option: on my show, I've said DHA from algae oil can be really beneficial, and if you don't eat fish, a vegan omega-3 made from algae supplies DHA and EPA.2

How much cod liver oil per day?

Here's how the label changes the math, using two real oils:

Sources: USDA FoodData Central, FDC ID 173577; the analyzed oil in the Norwegian winter trial; Institute of Medicine upper limit for preformed vitamin A.136

With an oil near the USDA figure, one teaspoon gives you 806 mg of EPA and DHA and 45% of the vitamin A upper limit, so make up the rest of your 2 to 3 grams with fish oil or a vegan omega-3 from algae. With a low-vitamin-A oil like the one in the Norwegian winter trial, about 2.2 to 3.3 teaspoons covers it. For your own bottle, divide your target in milligrams by the EPA plus DHA in one teaspoon to get your teaspoons, then multiply that number by the vitamin A in one teaspoon. Count every other source of preformed vitamin A toward the 3,000 mcg: a multivitamin, and beef liver averaged across the week. My Hypothyroidism Protocol pairs grass-fed liver once a week with cod liver oil dosed per label,19 and 3 ounces of beef liver once a week averages about 940 mcg of vitamin A a day, which is fine unless your bloodwork shows vitamin A running high.38 Our guide to how much omega-3 per day covers other sources, and if you've had atrial fibrillation, read the safety section before you go above 1 gram a day.

Liquid or capsules?

Both work. Liquid gives you a full teaspoon at once; softgels hold much less per capsule, so count how many it takes to match the label's per-teaspoon numbers. Softgels are usually made with gelatin, so choose ones made with fish or beef gelatin. Take either one with a meal.5

In the Norwegian winter trial, burping was reported by 2.4% on cod liver oil and 2.5% on placebo.3 My own body responds very well to wild-caught salmon; I could eat it three times a day. Fish oil capsules were a different story for me: historically they made me burp, and sometimes my skin even broke out, so I could tell I wasn't absorbing them well. I still think fish oil capsules are helpful.2 If you get fish burps, you're probably not fully digesting the oil, and sometimes that comes from low bile flow from your liver and gallbladder.7 If burps persist, see our guide to bile salts.

Cod liver oil for kids

For children, vitamin A sets the ceiling. The daily upper limits for preformed vitamin A are 600 mcg at ages 1 to 3, 900 mcg at ages 4 to 8 and 1,700 mcg at ages 9 to 13,6 so a teaspoon of an oil near USDA's 1,350 mcg is over the limit for children under 9, while a teaspoon of a low-vitamin-A oil, around 250 mcg, fits within it.

In a New York study, researchers picked at random which of two pediatric offices would give the treatment. At one, 47 children aged 6 months to 5 years took a teaspoon of lemon-flavored cod liver oil a day (half for babies under 1) plus half a tablet of a children's multivitamin with selenium for 5 to 6 months, and their visits for upper respiratory problems fell over time, while visits at the other office didn't change.39 Because the children took the oil with a multivitamin, the result reflects the two together. Set your child's amount with their practitioner.

How to choose a cod liver oil

As I've said on my show, many omega-3 supplements aren't in the right form, so look for the triglyceride form.7 Quality varies too. When researchers tested all 32 fish oil supplements sold in capsules in New Zealand, only 3 contained at least the EPA and DHA on the label, and 83% were over the recommended limit for peroxides, an early sign of oxidation.40 A later analysis of 47 New Zealand products, led by the omega-3 industry's trade association, found 91% met their EPA and DHA claims under the local standard of at least 90% of the label.41 Use this checklist when you buy:

• EPA, DHA, vitamin A and vitamin D per serving, printed on the label, so you can do the math in the how-much section

• Third-party tested for oxidation and contaminants, with results the maker will share

• Natural triglyceride form, which absorbed better than ethyl-ester concentrates in a 2-week study10

• Wild-caught cod, named on the label

• A dark glass bottle, kept in the fridge once it's open

• The smell test: fresh oil smells mildly of the sea; a sharp, rancid smell means it has gone off, so toss it

Cod liver oil side effects and safety

A few situations call for less cod liver oil, or none:

• Too much vitamin A. The adult upper limit for preformed vitamin A is 3,000 mcg a day from all foods and supplements, and 2,800 mcg at ages 14 to 18.6 Two Norwegian population studies, of 17,528 adults and 3,052 women, linked the older, higher-vitamin-A formula to more adult-onset asthma and, in women who took it through childhood, lower bone density, and the authors pointed to its vitamin A as a possible explanation.178 In a study that followed 72,337 postmenopausal women for 18 years, the top fifth of vitamin A intake (3,000 mcg a day or more) went with a 48% higher risk of hip fracture, mostly from retinol.45 Read your label, count every source, and if your bloodwork shows vitamin A running high, cut back and work with your practitioner.

• Pregnancy. Very high preformed vitamin A intake can be a problem, especially in pregnancy, and the same upper limits apply.6 In a study that followed 22,748 pregnant women, the rate of certain birth defects rose when women took more than about 10,000 IU (3,000 mcg) a day of preformed vitamin A from supplements, with the extra risk concentrated in the first 7 weeks.46 Two other studies found no rise in major malformations at those intakes: one followed 423 pregnancies exposed to 10,000 IU or more a day in the first 9 weeks, with 311 babies checked, and the other compared 1,508 women.4748 The UK's National Health Service advises against cod liver oil and other supplements containing vitamin A in pregnancy.49 If you're pregnant or planning to be, check with your OB and confirm the dose before you take cod liver oil.

• Atrial fibrillation. In heart-outcome trials of older adults, omega-3 supplements went with more atrial fibrillation, and more so at higher doses: across 7 trials with 81,210 people, the risk was 12% higher at 1 gram a day or less and 49% higher above 1 gram.50 If you've had atrial fibrillation, ask the doctor who manages it before you take more than 1 gram a day.

• Surgery. In the review of 52 publications, fish oil didn't increase bleeding during or after surgery, and the authors found no need to stop it beforehand.43 Tell your surgeon you take it and follow their instructions.

• Fish allergy. If you're allergic to fish, skip cod liver oil.

• Children. Their vitamin A limits are much lower; the kids section under how much to take sets the amounts.

See our guide to omega-3 side effects for more on the fats themselves, and our guide to natural blood thinners for other foods and herbs that affect clotting.

The bottom line

Cod liver oil: frequently asked questions

References

1. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central: Fish oil, cod liver. FDC ID 173577. SR Legacy (per 100 g: energy 902 kcal; vitamin A 30,000 mcg RAE; vitamin D 250 mcg (10,000 IU); EPA 6.9 g; DHA 11.0 g; DPA 0.935 g; saturated 22.6 g, monounsaturated 46.7 g, polyunsaturated 22.5 g; cholesterol 570 mg; 1 tsp = 4.5 g, 1 tbsp = 13.6 g). Accessed October 12, 2026.
2. Axe J. 7 Foods That Quiet Inflammation Better Than Supplements. The Dr. Josh Axe Show. 2026. Dr. Axe's own experience with salmon and fish oil capsules at 8:16; fish first and an omega-3 in triglyceride form such as cod liver oil at 8:48; DHA from algae oil at 9:06; wild-caught fish over fish oil supplements at 9:47. YouTube: https://www.youtube.com/watch?v=JFeUM50IzBI
3. Brunvoll SH, Nygaard AB, Ellingjord-Dale M, Holland P, Istre MS, Kalleberg KT, et al. Prevention of covid-19 and other acute respiratory infections with cod liver oil supplementation, a low dose vitamin D supplement: quadruple blinded, randomised placebo controlled trial. BMJ. 2022;378:e071245. doi:10.1136/bmj-2022-071245. PMID:36215222
4. Galarraga B, Ho M, Youssef HM, Hill A, McMahon H, Hall C, et al. Cod liver oil (n-3 fatty acids) as an non-steroidal anti-inflammatory drug sparing agent in rheumatoid arthritis. Rheumatology (Oxford). 2008;47(5):665-9. doi:10.1093/rheumatology/ken024. PMID:18362100
5. Axe J. The Anti-Inflammatory Reset: The 30-Day Healing Protocol. DrAxe.com protocol. 2026 ("What cools inflammation": omega-3s as the resolving fat, with joint aches, low mood and high triglycerides when low; p. 20, top 8 anti-inflammatory herbs and nutrients: omega-3 (EPA/DHA) 2–3 g daily with food, and omega-3s can add to the effect of blood thinners; p. 22, top 10 foods: wild salmon and sardines 4–6 oz, 3× weekly).
6. Institute of Medicine (US) Panel on Micronutrients. Vitamin A. In: Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academies Press; 2001. Chapter 4. doi:10.17226/10026
7. Axe J. How to Prevent CANCER: 15 Proven Ways to Lower Your Risk. The Dr. Josh Axe Show. 2026. Cod liver oil or fish oil on days without wild-caught fish at 39:04; supplements not in the right form, fish burps and bile flow at 39:04 and 39:32. YouTube: https://www.youtube.com/watch?v=Gsw5UuDlHDY
8. Forsmo S, Fjeldbo SK, Langhammer A. Childhood cod liver oil consumption and bone mineral density in a population-based cohort of peri- and postmenopausal women: the Nord-Trondelag Health Study. Am J Epidemiol. 2008;167(4):406-11. doi:10.1093/aje/kwm320. PMID:18033763
9. Brustad M, Braaten T, Lund E. Predictors for cod-liver oil supplement use--the Norwegian Women and Cancer Study. Eur J Clin Nutr. 2004;58(1):128-36. doi:10.1038/sj.ejcn.1601759. PMID:14679378
10. Dyerberg J, Madsen P, Møller JM, Aardestrup I, Schmidt EB. Bioavailability of marine n-3 fatty acid formulations. Prostaglandins Leukot Essent Fatty Acids. 2010;83(3):137-41. doi:10.1016/j.plefa.2010.06.007. PMID:20638827
11. Axe J. The BIGGEST Causes of Fast-Aging Skin (How to Reverse Aging). The Dr. Josh Axe Show. 2025. Cod liver oil as the classic and the surest bet at 23:52; vitamin A and vitamin D along with the omegas, a more food-based, less processed form of fish oil, at 24:02. YouTube: https://www.youtube.com/watch?v=tsTht-zHz-U
12. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central: Fish oil, sardine. FDC ID 173578. SR Legacy (per 100 g: energy 902 kcal; vitamin A 0 mcg RAE; vitamin D 8.3 mcg (332 IU); EPA 10.1 g; DHA 10.7 g; 1 tsp = 4.5 g). Accessed October 12, 2026.
13. Axe J, Rubin J. The Biblio Diet. Hachette Book Group; 2025. ISBN 9781546008439. Fish guidance ("Hooked on Fish," ebook p. 84: omega-3s concentrated in cold-water fish "as well as in cod liver oil"; "Choose wild, ocean-caught fish. Make sure it has fins and scales.").
14. The Holy Bible, King James Version. Leviticus 11:9. Project Gutenberg eBook #10.
15. Rajakumar K. Vitamin D, cod-liver oil, sunlight, and rickets: a historical perspective. Pediatrics. 2003;112(2):e132-5. doi:10.1542/peds.112.2.e132. PMID:12897318
16. U.S. Food and Drug Administration. Daily Value on the Nutrition and Supplement Facts Labels (total fat 78 g; saturated fat 20 g; cholesterol 300 mg; vitamin A 900 mcg RAE; vitamin D 20 mcg). fda.gov
17. Mai XM, Langhammer A, Chen Y, Camargo CA Jr. Cod liver oil intake and incidence of asthma in Norwegian adults--the HUNT study. Thorax. 2013;68(1):25-30. doi:10.1136/thoraxjnl-2012-202061. PMID:22977130
18. Helland IB, Smith L, Saarem K, Saugstad OD, Drevon CA. Maternal supplementation with very-long-chain n-3 fatty acids during pregnancy and lactation augments children's IQ at 4 years of age. Pediatrics. 2003;111(1):e39-44. doi:10.1542/peds.111.1.e39. PMID:12509593
19. Axe J. The Hypothyroidism Protocol. DrAxe.com protocol. 2026. Nourish phase, days 8–30 ("Grass-fed liver, once weekly"; "Vitamin A / cod liver oil — per label"); tiered supplement protocol ("Vitamin D3 + K2 — 2,000–5,000 IU, dose to labs").
20. Wang T, Zhang X, Zhou N, Shen Y, Li B, Chen BE, et al. Association Between Omega-3 Fatty Acid Intake and Dyslipidemia: A Continuous Dose-Response Meta-Analysis of Randomized Controlled Trials. J Am Heart Assoc. 2023;12(11):e029512. doi:10.1161/JAHA.123.029512. PMID:37264945
21. Middleton P, Gomersall JC, Gould JF, Shepherd E, Olsen SF, Makrides M. Omega-3 fatty acid addition during pregnancy. Cochrane Database Syst Rev. 2018;11(11):CD003402. doi:10.1002/14651858.CD003402.pub3. PMID:30480773
22. Stammers T, Sibbald B, Freeling P. Efficacy of cod liver oil as an adjunct to non-steroidal anti-inflammatory drug treatment in the management of osteoarthritis in general practice. Ann Rheum Dis. 1992;51(1):128-9. doi:10.1136/ard.51.1.128. PMID:1540019
23. Kavyani Z, Musazadeh V, Fathi S, Hossein Faghfouri A, Dehghan P, Sarmadi B. Efficacy of the omega-3 fatty acids supplementation on inflammatory biomarkers: An umbrella meta-analysis. Int Immunopharmacol. 2022;111:109104. doi:10.1016/j.intimp.2022.109104. PMID:35914448
24. Skúladóttir GV, Gudmundsdóttir E, Olafsdóttir E, Gudmundsson TV, Hardarson T, Kristinsson A, et al. Influence of dietary cod liver oil on fatty acid composition of plasma lipids in human male subjects after myocardial infarction. J Intern Med. 1990;228(6):563-8. doi:10.1111/j.1365-2796.1990.tb00280.x. PMID:2280233
25. Lee YH, Bae SC, Song GG. Omega-3 polyunsaturated fatty acids and the treatment of rheumatoid arthritis: a meta-analysis. Arch Med Res. 2012;43(5):356-62. doi:10.1016/j.arcmed.2012.06.011. PMID:22835600
26. Senftleber NK, Nielsen SM, Andersen JR, Bliddal H, Tarp S, Lauritzen L, et al. Marine Oil Supplements for Arthritis Pain: A Systematic Review and Meta-Analysis of Randomized Trials. Nutrients. 2017;9(1):42. doi:10.3390/nu9010042. PMID:28067815
27. Helland IB, Smith L, Blomén B, Saarem K, Saugstad OD, Drevon CA. Effect of supplementing pregnant and lactating mothers with n-3 very-long-chain fatty acids on children's IQ and body mass index at 7 years of age. Pediatrics. 2008;122(2):e472-9. doi:10.1542/peds.2007-2762. PMID:18676533
28. Hansen MW, Ørn S, Erevik CB, Bjørkavoll-Bergseth MF, Skadberg Ø, Melberg TH, et al. Regular consumption of cod liver oil is associated with reduced basal and exercise-induced C-reactive protein levels; a prospective observational trial : A NEEDED (The North Sea Race Endurance Exercise Study) 2014 sub-study. J Int Soc Sports Nutr. 2021;18(1):51. doi:10.1186/s12970-021-00437-1. PMID:34183020
29. Raeder MB, Steen VM, Vollset SE, Bjelland I. Associations between cod liver oil use and symptoms of depression: the Hordaland Health Study. J Affect Disord. 2007;101(1-3):245-9. doi:10.1016/j.jad.2006.11.006. PMID:17184843
30. Calder PC. Omega-3 fatty acids and inflammatory processes: from molecules to man. Biochem Soc Trans. 2017;45(5):1105-1115. doi:10.1042/BST20160474. PMID:28900017
31. Axe J. The 25 Root-Cause Bloodwork Markers That Matter Most. DrAxe.com protocol. 2026 (marker 04, Omega-3 Index: EPA + DHA as a percentage of red blood cell membranes, functional range ≥8%; actions: wild salmon, sardines, mackerel 3× weekly, EPA+DHA in triglyceride form, eliminate canola, corn, soybean and sunflower oils, retest at 6 months).
32. Harris WS, Tintle NL, Etherton MR, Vasan RS. Erythrocyte long-chain omega-3 fatty acid levels are inversely associated with mortality and with incident cardiovascular disease: The Framingham Heart Study. J Clin Lipidol. 2018;12(3):718-727.e6. doi:10.1016/j.jacl.2018.02.010. PMID:29559306
33. Axe J, Cole W. Heal Your Cells. Avery; 2026. ISBN 9798217181353. Optimal-ranges table (Vitamin D (25-OH): optimal (functional) 50–80 ng/mL).
34. Hu Y, Hu FB, Manson JE. Marine Omega-3 Supplementation and Cardiovascular Disease: An Updated Meta-Analysis of 13 Randomized Controlled Trials Involving 127 477 Participants. J Am Heart Assoc. 2019;8(19):e013543. doi:10.1161/JAHA.119.013543. PMID:31567003
35. Muldoon MF, Laderian B, Kuan DC, Sereika SM, Marsland AL, Manuck SB. Fish oil supplementation does not lower C-reactive protein or interleukin-6 levels in healthy adults. J Intern Med. 2016;279(1):98-109. doi:10.1111/joim.12442. PMID:26497831
36. Axe J. Perimenopause & Menopause: The 90-Day Healing Protocol. DrAxe.com protocol. 2026 (p. 13, what the transition takes from you: omega-3 (EPA/DHA), the brain and vessel fat; vitamin D3 + K2, the bone directors; supplement phase: omega-3 (EPA/DHA) 2–3 g daily with food).
37. U.S. Food and Drug Administration and U.S. Environmental Protection Agency. Advice about Eating Fish (pregnancy and breastfeeding: 8 to 12 ounces a week of a variety of seafood lower in mercury; 2 to 3 servings a week from the Best Choices list). Revised October 2021. fda.gov
38. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central: Beef, variety meats and by-products, liver, cooked, pan-fried. FDC ID 168627. SR Legacy (vitamin A 7,740 mcg RAE per 100 g, about 6,580 mcg per 3-ounce (85 g) serving). Accessed October 12, 2026.
39. Linday LA, Shindledecker RD, Tapia-Mendoza J, Dolitsky JN. Effect of daily cod liver oil and a multivitamin-mineral supplement with selenium on upper respiratory tract pediatric visits by young, inner-city, Latino children: randomized pediatric sites. Ann Otol Rhinol Laryngol. 2004;113(11):891-901. doi:10.1177/000348940411301108. PMID:15562899
40. Albert BB, Derraik JG, Cameron-Smith D, Hofman PL, Tumanov S, Villas-Boas SG, et al. Fish oil supplements in New Zealand are highly oxidised and do not meet label content of n-3 PUFA. Sci Rep. 2015;5:7928. doi:10.1038/srep07928. PMID:25604397
41. Bannenberg G, Mallon C, Edwards H, Yeadon D, Yan K, Johnson H, et al. Omega-3 Long-Chain Polyunsaturated Fatty Acid Content and Oxidation State of Fish Oil Supplements in New Zealand. Sci Rep. 2017;7(1):1488. doi:10.1038/s41598-017-01470-4. PMID:28469193
42. Bender NK, Kraynak MA, Chiquette E, Linn WD, Clark GM, Bussey HI. Effects of Marine Fish Oils on the Anticoagulation Status of Patients Receiving Chronic Warfarin Therapy. J Thromb Thrombolysis. 1998;5(3):257-261. doi:10.1023/A:1008852127668. PMID:10767122
43. Begtrup KM, Krag AE, Hvas AM. No impact of fish oil supplements on bleeding risk: a systematic review. Dan Med J. 2017;64(5):A5366. PMID:28552094
44. U.S. National Library of Medicine, DailyMed. Isotretinoin capsules (Aurobindo Pharma Limited): prescribing information, section 7.1 Vitamin A.
45. Feskanich D, Singh V, Willett WC, Colditz GA. Vitamin A intake and hip fractures among postmenopausal women. JAMA. 2002;287(1):47-54. doi:10.1001/jama.287.1.47. PMID:11754708
46. Rothman KJ, Moore LL, Singer MR, Nguyen US, Mannino S, Milunsky A. Teratogenicity of high vitamin A intake. N Engl J Med. 1995;333(21):1369-73. doi:10.1056/NEJM199511233332101. PMID:7477116
47. Mastroiacovo P, Mazzone T, Addis A, Elephant E, Carlier P, Vial T, et al. High vitamin A intake in early pregnancy and major malformations: a multicenter prospective controlled study. Teratology. 1999;59(1):7-11. doi:10.1002/(SICI)1096-9926(199901)59:1<7::AID-TERA4>3.0.CO;2-6. PMID:9988877
48. Mills JL, Simpson JL, Cunningham GC, Conley MR, Rhoads GG. Vitamin A and birth defects. Am J Obstet Gynecol. 1997;177(1):31-6. doi:10.1016/s0002-9378(97)70434-4. PMID:9240579
49. National Health Service (UK). Pregnancy vitamins and supplements ("Do not take cod liver oil or supplements containing vitamin A (sometimes called retinol) when you're pregnant"). nhs.uk. Page last reviewed June 3, 2026.
50. Gencer B, Djousse L, Al-Ramady OT, Cook NR, Manson JE, Albert CM. Effect of Long-Term Marine ɷ-3 Fatty Acids Supplementation on the Risk of Atrial Fibrillation in Randomized Controlled Trials of Cardiovascular Outcomes: A Systematic Review and Meta-Analysis. Circulation. 2021;144(25):1981-1990. doi:10.1161/CIRCULATIONAHA.121.055654. PMID:34612056

Dr. Josh Axe, DC, DNM, CNS

Doctor of Natural Medicine · Founder, DrAxe.com

Dr. Axe is a certified doctor of natural medicine, clinical nutritionist, and multiple New York Times bestselling author. He has spent 20+ years in clinical practice helping people heal at the root cause and founded one of the most-visited natural-health platforms in the world.

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