by Taylor Wolfram, MS, RDN, LDN and Jack Norris, RD
Depending on the laboratory, a normal range for white blood cell count (WBC) is about 3.5 to 12.5 billion per liter. One cross-sectional study showed vegans have a lower white blood cell count than omnivores, though in the normal range at 5.8 (Haddad, 1999). It appears that many vegans, however, have a lower than normal white blood cell count. We don’t really know why this is, but it appears to be common and not indicative of any obvious problem. If you have a white blood cell count below normal, you should talk to your doctor about whether to be concerned.
White Blood Cells
Also known as leukocytes, white blood cells are needed to fight foreign invaders, including bacteria, viruses, and cancerous cells. During infections, they typically increase in number. A concise explanation of the various white blood cells, along with some interesting pictures, can be found on Britannica (link).
White Blood Cells in Vegans
Anecdotally, many vegans report having low white blood cell counts, which their doctors are rarely concerned about. In contrast, the published research (below) shows vegans to have normal white blood cell counts, though typically lower than omnivores.
A study of 83 American vegetarians, including 13 vegans, found that white blood cell count tended to decrease in men with decreasing animal products in the diet (Dong & Scott, 1982). Many of the participants in this study followed a “natural hygiene” diet consisting mainly of raw vegetables, fruits, nuts, and seeds with minimal grains, legumes, dairy, and dietary supplements.
A study of 25 vegans and 20 meat-eaters found that vegans had lower levels of white blood cells (Haddad, 1999). Vegans had significantly lower concentrations of leukocytes (4.96 ± 0.91× 109/l in vegans compared to 5.83 ± 1.51 × 109/l in meat-eaters) and lymphocytes (1.56 ± 0.39 × 109/l in vegans compared to 1.90 ± 0.59 × 109/l in meat-eaters). These values are all within the normal ranges. After considering other immune-related parameters, the authors concluded, “It is not possible to determine from these findings whether the immune status of vegans is compromised or enhanced compared with other groups.”
A clinical trial from the University of Memphis placed mostly healthy and some vegetarian subjects on a “Daniel Fast” for 21 days, eating only plant foods with no processed or packaged foods, and their white blood cell count went from an average of 5.7 to 5.0 (Bloomer, 2010).
A cross-sectional study from Britain included 398 vegans among 447,726 white participants and 5,237 Indian participants. Among the white participants they found that non-smoking vegans’ white blood cell count (6.22 x 109 cells/l, 95% CI 6.01 to 6.43 x 109 cells/l) was significantly lower than the participants who were regular meat-eaters (7.02 x 109 cells/l, 95% CI 7.01 to 7.03 x 109 cells/l), low meat-eaters (6.80 x 109 cells/l, 95% CI 6.79 to 6.81 x 109 cells/l), poultry eaters (6.55 x 109 cells/l, 95% CI 6.49 to 6.61 x 109 cells/l), and vegetarians (6.69 x 109 cells/l, 95% CI 6.63 to 6.74 x 109 cells/l), but not significantly lower than fish eaters (Tong, 2019). Vegans’ white blood cell count was within the reference range. White vegetarians had a significantly lower white blood cell count (6.69 x 109 cells/l, 95% CI 6.63 to 6.74 x 109 cells/l) than white meat, fish, and poultry eaters. However, the Indian vegetarians’ white blood cell count (7.30 x 109 cells/l, 95% CI 7.21 to 7.39 x 109 cells/l) didn’t differ significantly from the Indian meat-eaters.
A randomized controlled trial put meat-eaters on a vegan diet for 4 weeks and their total leukocyte count dropped from 6.0 ± 1.4 to 5.4 ± 0.9 x 109/l. The leukocyte count of those on a vegan diet was significantly lower than the comparison group on a meat-based diet but remained within the reference range (Lederer, 2020).
So why do vegans have lower white blood cell counts than omnivores? There are several hypotheses:
- Zinc deficiency — zinc plays a role in the production of white blood cells although vegans didn’t have significantly lower zinc intakes or serum zinc levels than meat-eaters in Haddad et al.
- Insufficient intake of branched chain amino acids (BCAA) — BCAA play a role in lymphocyte functionality; Lederer et al. hypothesize that the mTOR signaling pathway downregulates white blood cell production when BCAAs are in low supply.
- Lower IGF-1 levels — IGF-1 plays a role in the production of white blood cells; McCarty suggests that vegans have lower IGF-1 levels which may contribute to their lower white blood cell count.
- Low vitamin A levels — vitamin A plays a role in the production of white blood cells, and vegans may have lower levels of vitamin A due to no direct dietary source, and potentially low carotenoid and/or fat intake; vegans did not have lower or insufficient intakes of vitamin A, in retinol equivalents, than meat-eaters in Haddad et al.
- Vitamin B12 deficiency — B12 plays a role in the production of white blood cells (though vegetarians, who also have low B12 intakes, didn’t have a significantly lower white blood cell count than meat-eaters in Tong et al.).
None of these hypotheses have been well-studied or proven. So for now, we cannot with any certainty say why vegans tend to have a lower white blood cell count.
Last updated April 2021
Bloomer RJ, Kabir MM, Canale RE, Trepanowski JF, Marshall KE, Farney TM, Hammond KG. Effect of a 21 day Daniel Fast on metabolic and cardiovascular disease risk factors in men and women. Lipids Health Dis. 2010 Sep 3;9:94.
Craddock JC, Neale EP, Peoples GE, Probst YC. Vegetarian-Based Dietary Patterns and their Relation with Inflammatory and Immune Biomarkers: A Systematic Review and Meta-Analysis. Adv Nutr. 2019 May 1;10(3):433-451. Not cited.
Dong A, Scott SC. Serum vitamin B12 and blood cell values in vegetarians. Ann Nutr Metab. 1982;26(4):209-16.
Haddad EH, Berk LS, Kettering JD, Hubbard RW, Peters WR. Dietary intake and biochemical, hematologic, and immune status of vegans compared with nonvegetarians. Am J Clin Nutr. 1999 Sep;70(3 Suppl):586S-593S.
Lederer AK, Maul-Pavicic A, Hannibal L, Hettich M, Steinborn C, Gründemann C, Zimmermann-Klemd AM, Müller A, Sehnert B, Salzer U, Klein R, Voll RE, Samstag Y, Huber R. Vegan diet reduces neutrophils, monocytes and platelets related to branched-chain amino acids – A randomized, controlled trial. Clin Nutr. 2020 Nov;39(11):3241-3250.
McCarty MF. Favorable impact of a vegan diet with exercise on hemorheology: implications for control of diabetic neuropathy. Med Hypotheses. 2002 Jun;58(6):476-86.
Tong TYN, Key TJ, Gaitskell K, Green TJ, Guo W, Sanders TA, Bradbury KE. Hematological parameters and prevalence of anemia in white and British Indian vegetarians and nonvegetarians in the UK Biobank. Am J Clin Nutr. 2019 Aug 1;110(2):461-472.
19 thoughts on “White Blood Cells in Vegans”
Brad, i agree with your observations, but IMHO you are in great shape at that leve. The lower the WBC the better IF you are healthy. Probably the only reason that lower than 3.5 is associated with high mortality is that these people already have a disease or cancer that lowers the count as compared to just low inflammation level for a person eating whole plant foods. The extremely low WBC is probably not the cause of the higher mortality, but a sign of illness. I rejoice at having the lower readings on WBC, and I haven’t died yet. If it were below 3 I would probably know already of an ailment that is responsible due to symptoms. But the lowest reading I ever had of 3.3 was while training for a triathlon 10 years ago and eating a lot more fruit and I was younger and healthier then than now. I don’t worry about WBC and actually hope I score 3.5 levels again this year! I’m almost 70 but health continues to improve. My daily regimen these days is about 1550 calories, no salt added, whole plant foods, mostly brown rice, legumes, sweet potato, tomatoes, peppers, oats, polenta, greens, and green tea. Occasionally, I binge on some nuts or peanuts, and the nuts seem to raise cholesterol a bit and probably WBC too, but not worried. haha!! Bottom line is that the values on lab tests showing 3.8 etc as LOW cause needless concern, and Greger observed the same thing. Low is good!! Observe the well being, my friend!
I wanted to ask whether the study carefully screened out participants with preexisting medical conditions (thyroid disorders, immune disorders, anemia, cancer, etc.) because obviously, unwell people may have already suffered from low WBC counts, skewing the results.
If they were healthy, the second question is whether there were common denominators in the deaths of those with low WBC counts. Infections would be the logical concern. But it would be interesting if many died of common cancers due to their low WBCs. Or perhaps another cause such as heart issues, which may not even be linked to this.
Looks like some solid data and very interesting from Brad’s cited study. Naturally, it is concerning for very healthy people to show up “low” on a CBC on something, but again, low on the “normal” scale in the USA is often better as in with BMI or WBC As Buddha said the middle way is the path. And the data cited agrees. Over last 10 years my avg is 4.0 with lowest at 3.3. There is going to be some variation by nature of the testing protocol alone so best not to draw conclusions from a single test. But when someone tells you they think the high fat, high meat diet is giving them a higher WBC a stronger immune system they don’t understand that it is marker of inflammation and that the immune system is already stressed and overworked. Too low on WBC one might suspect cancer or something maybe and should check into it outside of that 3.4 range. But Brad’s data is reassuring. Bon appetit!
Note that for under 3.5, the increased mortality risk was 3x worse than 3.5- 6. Based on the limited study data, being under 3.5 was worse than being at 10 in the study. So while being low is probably good, too low may be worse than too high.
Since green vegetables have an association with low WBC in one study, people trying to raise their WBC might try cutting back. I am experimenting with that now. I am at 3.7 on my last test, which is in the optimal zone. However, I would feel greater comfort at 4 since I have fallen below 3.5 at times.
Fasting will make one’s wbc fall like a rock. (I know that from personal experience and from the literature.) I would imagine the same thing would happen with caloric restriction.
It seems to me that the lowest all cause mortality in perhaps the largest study on the topic was between 3.5 -4.5. I don’t know that it’s good idea to be under 3.5 based upon the increased mortality risk found in that study. The sample size under 3.5, however, was extremely small.
“Above the threshold of 3,500 WBC/mm3, the estimated mortality risk was 11% higher per each baseline additional increase of 1,000 WBC/mm3.”
“Participants with WBC 10,000 had 2-fold higher mortality (HR 2.12, 95% CI 1.45 to 3.08) compared with subjects with WBC 3,501 to 6,000. ”
“Participants with WBC 10,000 had 2-fold higher mortality (HR 2.12, 95% CI 1.45 to 3.08) compared with subjects with WBC 3,501 to 6,000.”
Ruggiero C, Metter EJ, Cherubini A, Maggio M, Sen R, Najjar SS, Windham GB, Ble A, Senin U, Ferrucci L. White blood cell count and mortality in the Baltimore Longitudinal Study of Aging. J Am Coll Cardiol. 2007 May 8
I’m female, 45 I’ve been vegan for 12 years. I consume a lot of nutritional yeast, organic tofu, green Veggies and take a multivitamin supplement every now and then.
I did a complete blood work 1 year ago (including hormones) and it was all balanced except for the blood white cells, which was low, close to minimum range.
I’m healthy – I don’t have any healthy problem and I rarelly have cold or any other illness (got covid twice though, but recovered quickly). My periods are regular in painless – I don’t have PMS since added organic tofu in my daily meals.
I wonder if low white cells in healthy vegan is due to consuming less food that causes inflamation in the body
‘Vegan’ has become the common label for those of us who do not eat animal food products. Every time I read of research on ‘vegans’ I hope it will show better health outcomes than those of animal-food eaters. I idenitfy as Wholefood Plant-based, respect the differences, and am sad to see the vicious bickering between people defending different labels. However, people call me ‘vegan’ regardless of what I prefer. I don’t not live up to the highest ideals of veganisim. At the same time many vegans do not live up to the ideals of healthy plant based eating. I’m worried that research on ‘vegans’ may be reflecting poor health outcomes in those vegans not eating wholefoods, or perhaps not taking their B12, etc. I want ‘vegan’ to triumph, for all the reasons we shun animal foods. Are you aware of any research on those vegans who also eat wholefoods? (including low-to-no oil?) It may well show different outcomes.
Ginny Messina just wrote an article on this very topic, Finding the Best Vegan Diet (And Why It’s Not Low-Fat).
Vegans not having an adequate intake of vitamin B12 has been a concern with regard to health outcomes in large observational studies. Sometimes results can be crudely adjusted for, or interpreted in light of, general vitamin B12 status. This 2020 study, Associations of Circulating Methylmalonic Acid and Vitamin B-12 Biomarkers Are Modified by Vegan Dietary Pattern in Adult and Elderly Participants of the Adventist Health Study 2 Calibration Study, and a few others, gives me the impression that vegans are more consistently supplementing with vitamin B12 than they were in the 1990s.
I stopped eating animal products for four years now and the result is that my health has improved enormously. I was a mucus generator before I stopped eating meat. Now I have a cold rarely, and I am, to a great extent, mucus free and healthy. I have a low white blood cell count, but I had that as a heavy meat and dairy eater in the past as well! Despite having the same low white blood cell count of the past, my health has improved so much. Scientists should look into this subject more intensively. A plant based diet had been proven to be a much better option in my case, than eating meat
Dr. Greger at Nutritionfacts.com has a couple of videos on why you want your WBC to be lower. The clear reason that a vegan would have lower WBC is that their level of inflammation is lower than those eating dead animals which cause all kinds of problems and inflammation. According to Greger’s research we should be shooting for levels below 4. What is considered low on lab test guidelines is actually optimal, but in a sick world of western meat filled diet normal is indicative of a population always trying to clean up heavy damage from the animal product laden diet.
Here is one of Greger’s discussions.
I went on the Esselstyn diet for 7 weeks and six days. My white blood cell count went down from 3500 to 2000. My doctor is very concerned and is sending me to a hematologist.
The intended consequence of my diet experiment with reduction of total cholesterol from 2:43 22:01. LDL reduction was from 131 to 112. HDL drop slightly from 94 to 74.
The unintended consequence of this diet experiment was to drastic reduction of white blood cell count.
Background-I am 74 years old, active in good health and conducted this diet experiment upon reading about the benefits of a plant-based diet which include arteries that produce nitric oxide, reduction of heart disease, reduction of most chronic diseases including diabetes and Cancer.
You might want to share this article with your doctors so they know low WBC’s can be a benign side effect of a vegan diet.
I’ve typically had a WBC between 2.1 to 2.9, with absolute neutrophils hovering around 0.9, which usually triggers a phone call from the lab to my MD. Then after my MD and I get a bit worried, I add some fish to my diet for a week and sure enough, my WBCs jump to about 3.4 and neutrophils to about 1.4 (bottom of normal range). Then I go back to being vegan. Typically with a super low CRP (0.3) and homocysteine (8.0) suggests that this isn’t a sign of problems; probably (hopefully) just clean food and healthy amounts of exercise.
I have been a vegan for 5 years and blood tests from the last 3 years show lower than the norm wbc as well. Doctors also not concerned because other blood factors normal. Interesting article though about this vegan wbc phenomenon!
Any ways to increase wbc while staying plant based?
Thanks for your comments. Fyi, Greger has a video on Nutrition Facts suggesting that white blood cells are linked to cvd problems and low numbers are a very good thing! But I’m still a bit anxious being this far below normal, and it sounds as though you may be as well. I’ll see any replies posted here, but if you find out anything about this, I’d love to know. Please circle back if you learn something.
thanks for your comment.
I actually saw a hematologist who found that in 2003 I had a WBC count of 2300/microliter, just a tad higher than my 2000 on Jun 1, 2018. She was not concerned. I will have my physical exam tomorrow and will discuss the hematologist’s report. The WBC count on Jun 15 was 2120, just a tad higher.
Pls find attached an excellent research paper on the correlation of inflammation with WBC count. The authors also discuss that due to the increase of C-Reactive Protein, IL-6 and angiotesin II, which increase with inflammation, and also increase the production of WBC by the medulla. This research has excellent references concerning the correlation of inflammation with chronic diseases such as obesity, hypertension, diabetes, thrombosis, etc.
In summary, the corollary from the above is: at low levels of inflammation, the levels of C-Reactive Protein, IL-6 and angiotesin II are low, as well as
the production of WBC by the medulla.
I was recently diagnosed with lower than normal WBC. I ,too, am a plant-based whole food consumer. My primary care physician is referring me to a blood specialist for the same concerns mentioned by my fellow repliers on this string. Being led to this article is an omen from God that my lifestyle changes (including exercise and spiritual meditation) have contributed to better health. I plan to add B12 to my diet, however, because research consistently shows that this vitamin is deficient in non omnivores.
Years later, Despite adding fish to my diet, I still hover slightly below below normal range. My diet is about 95% plants. Before adding fish, I was even lower. So the theory and research listed above makes a lot of sense.
I had low white blood cells all my life. It however goes up and down since I became vegan. However it doesn’t make me more vulnerable to infections as a vegan. As I matter of fact I am at least twice as healthy and have a lot more stamina since going plant based.