Vitamin D: One of the Few Supplements Paleo Dieters… | The Paleo Diet®
noun_Search_345985 Created with Sketch.

Try The Paleo Diet®!

Learn more. Get recipes & meal plans. See the science.

Vitamin D: One of the Few Supplements Paleo Dieters May Require

By Loren Cordain, Ph.D., Professor Emeritus, Founder of The Paleo Diet
March 18, 2016
Vitamin D: One of the Few Supplements Paleo Dieters May Require image

One of the most persuasive aspects of contemporary Paleo Diets is that you will not have to waste your hard earned dollars on supplements (1, 2). Once you get going on this lifetime program of eating, except for Vitamin D and possibly fish oil, you will achieve all of the DRI’s recommended by governmental agencies from just the food you eat (1, 2). Previously, I have extensively covered the calcium issue in a number of scientific publications (2-4), so in this blog, I want to re-emphasize the importance of vitamin D supplementation for health and well being. As we come out of wintertime and into early spring, the possibility exists that many of us may be vitamin D compromised or even Vitamin D deficient (5-11).

Why is this? When we eat the foods that mother nature intended, why should we be deficient in any nutritional element? Vitamin D is actually not a vitamin, but rather is a hormone naturally formed in our skins when we expose ourselves to the ultraviolet radiation of the sun. In North America and in Europe, we receive scant little sunshine in the dead of winter, and consequently our body stores of this essential hormone become depleted as we go from fall to winter to early spring (5-11).

Table 1 below lists the content of the 40 most concentrated sources of vitamin D in real, non-fortified foods. Careful examination of this table makes it clear that, except for salmon or fresh tuna (12), it is difficult or even impossible to achieve recommended vitamin D intakes (600 I.U. or greater per day) (10, 11) with real, non-fortified foods.

Table 1. The 40 most concentrated sources of Vitamin D in real, non-fortified foods in the western diet.

Food 100 grams foodVit D I.U.kcalVit D IU/kcalVit D IU/100 kcal
Cod liver oil10010,00090211.091109
Catfish, Channel, Wild, Dry Heat1005681055.41541
Tuna (bluefin), Fresh, wild, baked/broiled1009201845.00500
Salmon, Coho (Silver), Wild, Baked/Broiled1006761394.86486
Salmon, Chinook (King), Wild, Baked1009042313.91391
Fish eggs (roe), mixed species1004841433.38338
Salmon, Sockeye, Wild Cooked Dry Heat1005261693.11311
Oysters, Pacific, Steamed1003201631.96196
Salmon, Atlantic Wild Baked1003281821.80180
Halibut, Atlantic/Paciific, Baked1001921401.37137
Salmon, Atlantic Farmed Baked1002722061.32132
Mushrooms, Oyster raw10036331.09109
Tuna, (yellow fin/albacore), baked/broiled1001401391.01101
Sardines in oil1001932080.9393
Tuna, Canned in water100801280.6363
Mushrooms, Potabella raw10012220.5555
Mushrooms, Shiitake raw10018340.5353
egg yolks1001873510.5353
Cod, Atlantic, Cooking dry heat100461050.4444
Beef, Kidney100681590.4343
Pork liver100521340.3939
Mushrooms, white1007220.3232
Beef liver100491750.2828
Cod, Pacific, Cooking dry heat10024850.2828
Turkey liver100722730.2626
Salmon oil1001779020.2020
Beef, Filet Mignon100362110.1717
Chicken liver100161190.1313
Pork loin100342730.1212
Lamb liver100161390.1212
Lamb, rib roast lean100242320.1010
Mushrooms, Enoki raw1004440.099
Catfish, Channel, Farmed, Dry Heat100101440.077
Pork kidney10081510.055

At the top of the list for natural foods is cod liver oil, which at first appears to be a great source of vitamin D. It is, but unfortunately it also contains high levels of vitamin A which competes with our bodies’ metabolism for vitamin D and may impair vitamin D metabolism (13). A better choice is fish oil from the body of fish, rather than the liver. It also contains vitamin D and the healthful long chain omega 3 fatty acids (EPA and DHA) without the higher concentrations of vitamin A which may impair vitamin D metabolism (13).

But from an evolutionary perspective, fish oil whether derived from cod liver oil or only the body of fish, was known to have been consumed by the Vikings (circa 700s to 1100 AD) but was not commercially manufactured until relatively recent (200 – 300 years) times.

Accordingly, the Paleo Diet paradigm suggests that (as a species) if we consumed vitamin D from food, it must have come from other sources. Table1 indicates that salmon is a concentrated source of vitamin D, and if we consume roughly ¼ pound of salmon or more per day (12), we may be able to achieve low level vitamin D balance. But who do you know who eats a quarter pound or more of salmon a day (day in and day out) in the 21st century?

As you move on down the list of foods in Table 1 from salmon, it becomes increasingly obvious that with our modern tastes and diets, few people could achieve vitamin D balance on any normal diets before modern, fortified foods (milk, margarine and processed foods) were introduced in about the 1930’s and 1940’s. Organ meats won’t do it, eggs won’t do it, shellfish won’t do it and meat won’t do it. The obvious implications of Table 1 is that food never was or never could have been the primary source of the hormone, vitamin D, which is essential for optimal human health. Before I leave this topic, let’s examine milk and dairy products.

Are Dairy Foods Good Sources of Vitamin D?

To even suggest that milk is a good source of vitamin D is a total stretch of the facts. The Institute of Medicine Daily’s recommended intake for vitamin D is 600 IU per day for most people (14). Although this advice represents a substantial increase from previous estimates, it still falls far short of human experimental evidence showing that at least 2,000 IU per day is required to keep blood levels of vitamin D at the ideal concentration of 30 ng/ml (6, 7, 10). See Table 2 below.

Table 2. Vitamin D Classifications in Blood.

Blood levels of vitamin DCategory
less than 20 ng/mlDeficiency
21 to 29 ng/mlInsufficiency
greater than 30 ng/mlSufficiency
60 ng/mlMaximal with sunlight exposure

An eight oz glass of raw milk (280 calories) straight from the cow without fortification gives you a paltry 3.6 IU of vitamin D. At this rate, you’d have to drink a ridiculous 167 eight oz glasses of milk just to achieve the 600 IU daily recommendation. Because most of the milk we drink is fortified with vitamin D, then an 8 oz glass typically yields 100 IU of this nutrient. However, even with fortification, you would have to drink six 8 oz glasses (1,680 calories or ~ 75 % of your daily caloric intake) of milk to meet the daily requirement for vitamin D. If you wanted to reach the 2,000 IU level as suggested by the world’s best vitamin D researchers, you would have to drink 20 eight oz glasses of fortified milk amounting to 5,600 calories. No one in their right mind would drink 20 glasses of milk a day, even if they could.

As you can see from these simple calculations, whether fortified or raw, milk is an abysmal source of vitamin D. The best way to get your vitamin D is not by drinking milk, but rather by getting a little daily sun exposure as nature intended.

Sunlight Exposure

Lifeguards and other outdoor workers can achieve blood concentrations that top out at about 60 ng/ml. But you really don’t need values this high. Most experts agree that values higher than 30 ng/ml will significantly reduce your risk for cancer and all of the other diseases associated with low vitamin D status (15-21). The good news is that daily sunlight exposure in the summertime for short periods 15-30 minutes will rapidly boost your blood levels of vitamin D above 30 ng/ml. Something that cannot be achieved with diet alone because almost all real foods, except salmon (12), that we commonly eat contain little or no vitamin D (Table 1).

Vitamin D Supplementation

For most of us, regular sunlight exposure is a luxury that is difficult or impossible to come by on a year round basis. Obviously, our hunter gatherer ancestors, living at low to moderate latitudes did not have this problem. Consequently, you will need to supplement your diet with vitamin D3 capsules. If we look at the official governmental recommendation for vitamin D intake (between 400 and 600 IU), it is woefully inadequate. This policy represents a complete failure in public health policy. The most recent human experiments show that blood levels of 30 ng/ml could never be achieved with vitamin intakes between 400 and 600 IU (6, 7, 10, 11). 400 IU does not help improve insufficient blood concentrations of vitamin D one iota. In fact, a recent series of articles and reviews published in Nutrients demonstrated that the 600 IU recommendation was based on a misinterpretation of the data and was an order of magnitude too low. A meta-analysis of existing studies conservatively estimated daily needs of 1885, 2802 and 6235 IU for normal weight, overweight, and obese individuals respectively (22-24).

The majority of men, women and children in the U.S. maintain blood levels of vitamin D which are either deficient or insufficient (6-11). Hence, one of the best strategies you can take with adopting The Paleo Diet is to supplement daily with vitamin D3 if you are unable to get sunshine on a regular basis. Most vitamin D experts agree that daily supplementation of at least 2,000 IU of vitamin D3 daily is necessary to achieve healthful blood levels of 30 ng/ml or greater.


[1] Cordain L. The Paleo Answer. John Wiley & Sons, New York, NY, 2012.

[2] Cordain L. The nutritional characteristics of a contemporary diet based upon Paleolithic food groups. J Am Neutraceut Assoc 2002; 5:15-24.

[3] Cordain L, Eaton SB, Sebastian A, Mann N, Lindeberg S, Watkins BA, O'Keefe JH, Brand-Miller J. Origins and evolution of the western diet: Health implications for the 21st century. Am J Clin Nutr 2005;81:341-54.

[4] O’Keefe JH, Bergman N, Carrera-Basto P, Fontes-Villalba M, DiNicolantonio JJ, Cordain L. Nutritional strategies for skeletal and cardiovascular health: hard bones, soft arteries, rather than vice versa. Open Heart 2016;3: e000325. doi:10.1136/ openhrt-2015-000325 (in press).

[5] Binkley N, Novotny R, Krueger D, Kawahara T, Daida YG, Lensmeyer G, Hollis BW, Drezner MK. Low vitamin D status despite abundant sun exposure. J Clin Endocrinol Metab. 2007 Jun;92(6):2130-5.

[6] Holick MF, Chen TC: Vitamin D deficiency: a worldwide problem with health consequences. Am J Clin Nutr. 2008 Apr;87(4):1080S-6S.

[7] Hollis BW. Circulating 25-hydroxyvitamin D levels indicative of vitamin D sufficiency: implications for establishing a new effective dietary intake recommendation for vitamin D. J Nutr. 2005 Feb;135(2):317-22.

[8] Kumar J, Muntner P, Kaskel FJ, Hailpern SM, Melamed ML. Prevalence and associations of 25-hydroxyvitamin D deficiency in US children: NHANES 2001-2004. Pediatrics. 2009 Sep;124(3):e362-70.

[9] Melamed ML, Kumar J. Low levels of 25-hydroxyvitamin D in the pediatric populations: prevalence and clinical outcomes. Ped Health. 2010 Feb;4(1):89-97.

[10] Vieth R. Why the optimal requirement for vitamin D3 is probably much higher than what is officially recommended for adults. J Steroid Biochem Mol Biol 2004; 89-90:575-9.

[11] Bischoff-Ferrari HA. Optimal serum 25-hydroxyvitamin D levels for multiple health outcomes. Adv Exp Med Biol. 2008;624:55-71

[12] Lu Z, Chen TC, Zhang A, Persons KS, Kohn N, Berkowitz R, Martinello S, Holick MF. An evaluation of the vitamin D3 content in fish: Is the vitamin D content adequate to satisfy the dietary requirement for vitamin D? J Steroid Biochem Mol Biol. 2007 Mar;103(3-5):642-4. Epub 2007 Jan 30.

[13] Cannell JJ, Vieth R, Willett W, Zasloff M, Hathcock JN, White JH, Tanumihardjo SA, Larson-Meyer DE, Bischoff-Ferrari HA, Lamberg-Allardt CJ, Lappe JM, Norman AW, Zittermann A, Whiting SJ, Grant WB, Hollis BW, Giovannucci E. Cod liver oil, vitamin A toxicity, frequent respiratory infections, and the vitamin D deficiency epidemic. Ann Otol Rhinol Laryngol. 2008 Nov;117(11):864-70.


[15] Dobnig H, Pilz S, Scharnagl H, Renner W, Seelhorst U, Wellnitz B, Kinkeldei J, Boehm BO, Weihrauch G, Maerz W. Independent association of low serum 25-hydroxyvitamin d and 1,25-dihydroxyvitamin d levels with all-cause and cardiovascular mortality. Arch Intern Med. 2008 Jun 23;168(12):1340-9.

[16] Field S, Newton-Bishop JA. Melanoma and vitamin D. Mol Oncol. 2011 Feb 3. [Epub ahead of print]

[17] Forouhi NG, Luan J, Cooper A, Boucher BJ, Wareham NJ. Baseline serum 25-hydroxy vitamin D is predictive of future glycaemic status and insulin resistance: The MRC Ely prospective study 1990-2000. Diabetes. 2008 Oct;57(10):2619-25.

[18] Holick MF. Vitamin D and sunlight: strategies for cancer prevention and other health benefits. Clin J Am Soc Nephrol 2008;3:1548-54.

[19] Holick MF. Optimal vitamin d status for the prevention and treatment of osteoporosis. Drugs Aging. 2007; 24(12):1017-29.

[20] Plum LA, DeLuca HF. Vitamin D, disease and therapeutic opportunities. Nat Rev Drug Discov. 2010 Dec;9(12):941-55

[21] Sharief S, Jariwala S, Kumar J, Muntner P, Melamed ML. Vitamin D levels and food and environmental allergies in the United States: Results from the National Health and Nutrition Examination Survey 2005-2006. J Allergy Clin Immunol. 2011 Feb 15.

[22] Heaney, R., et al., Letter to Veugelers, P.J. and Ekwaru, J.P., A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D. Nutrients 2014, 6, 4472-4475; doi:10.3390/nu6104472. Nutrients, 2015. 7(3): p. 1688-1690.

[23] Veugelers, P.J. and J.P. Ekwaru, A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D. Nutrients, 2014. 6(10): p. 4472-4475.

[24] Veugelers, P.J., T.M. Pham, and J.P. Ekwaru, Optimal Vitamin D Supplementation Doses that Minimize the Risk for Both Low and High Serum 25-Hydroxyvitamin D Concentrations in the General Population. Nutrients, 2015. 7(12): p. 10189-10208.

Even More Articles For You

Dr Cordain Answers a Reader's Question About Egg White Lysozyme
Read our latest article where Dr. Cordain talks about egg white lysozyme. Browse The Paleo Diet® website for Paleo Diet recipes, meal plans & more!
By Loren Cordain, Ph.D.
5 Tips for Going Paleo on a Budget
The Paleo Diet focuses on healthy, natural foods. While that may mean a few more trips to the grocery store, it doesn't have to break the bank. Here's how.
By The Paleo Diet® Team
Nell's Corner: Do you need a flu shot, or is food good enough?
What should you do if you want to arm yourself against influenza but prefer a more natural line of defense? Focus on optimizing your gut health!
By Nell Stephenson
Paleo Leadership
Trevor Connor
Trevor Connor

Dr. Loren Cordain’s final graduate student, Trevor Connor, M.S., brings more than a decade of nutrition and physiology expertise to spearhead the new Paleo Diet team.

Mark J Smith
Dr. Mark Smith

One of the original members of the Paleo movement, Mark J. Smith, Ph.D., has spent nearly 30 years advocating for the benefits of Paleo nutrition.

Nell Stephenson
Nell Stephenson

Ironman athlete, mom, author, and nutrition blogger Nell Stephenson has been an influential member of the Paleo movement for over a decade.

Loren Cordain
Dr. Loren Cordain

As a professor at Colorado State University, Dr. Loren Cordain developed The Paleo Diet® through decades of research and collaboration with fellow scientists around the world.