Category Archives: Lymphocytes

Neutrophils, Lymphocytes, Monocytes: What’s Optimal For Health And Longevity?

White blood cells (WBCs) comprise many different cell types, including neutrophils, lymphocytes, monocytes, eosinophils, and basophils.

Neutrophils, lymphocytes, and monocytes account for ~99% of WBCs, and accordingly, in the video I propose optimal ranges for these cell types in terms of health and longevity.


Quantifying Biological Age: Blood Test #5 in 2020

My latest blood test results are in-how’s my biological age?

In the video I discuss my dietary approach prior to my latest blood test, the blood test results, and my plan to improve them with diet going forward.

Biological Age: Optimal On A Carnivore Diet?

After going on Joe Rogan’s podcast, Paul Saladino, MD, posted his show notes, which included his blood test results. Based on that data, is his biological age optimal while on a carnivore diet?

Biological Age Test #4 in 2020: Getting Better or Getting Worse?

My latest blood test results are in-how’s my biological age? In the video I discuss my dietary approach prior to my latest blood test, the blood test results, and my plan to improve them going forward.

Quantifying Biological Age: Blood Test Measurement #3 in 2020

In this video, I discuss data for 6 blood test measurements since 2018 that show a Phenotypic (Biological) Age that is ~14 years than my current age (47y).

Blood Test Analysis In A 100 Year Old Subject

What are the blood biomarkers of a centenarian, and is there room for improvement? Find out in the video below!

Optimizing Biological Presentation

In the first 45 minutes, discuss each of the biomarkers contained within Levine’s Biological Age calculator, Phenotypic Age.

After that, I answer questions from the audience and we discuss all things related to aging.

15+ Years Younger Than My Chronological Age: Blood Test #2 In 2020

Exactly 1 month ago, my first biological age measurement of 2020 was 32.75y ( When considering that my chronological age is 47y, that’s a 14 year improvement, but I wasn’t (and still aren’t) satisfied. When I sent my blood for analysis, I was battling a mild upper respiratory infection (cough, no fever), which likely raised my WBCs, thereby resulting in a higher biologic age. Also, I was experimenting with a higher intake of meat, eggs, and cheese, to see what affect that it would have on my circulating biomarkers. On that blood test in February, my creatinine levels were higher than my 2015-2020 average value, and if those foods were associated with circulating levels of creatinine, reducing them should also reduce creatinine, and accordingly, further improve my biological age. I also assumed that all other variables on Levine’s Phenotypic Age calculator would be unchanged.

On March 9 2020, I sent my blood for analysis so that I could calculate biological age with Levine’s PhenotypicAge. Almost exactly as expected, my WBCs (4.7 * 10^3 cells/microliter) were closer to my 2015-2020 average value (4.6), rather than the higher value (5.8) in my blood test last month. Similarly, reducing my intake of beef, eggs, and cheese brought creatinine from 1.08 to 0.97 mg/dL, which is closer to its 5-year average (0.94 mg/dL). As a result, I further reduced my biological age by 1.14 years to 31.61y, which is 15+ years younger than my chronological!

pa 3.9.2020

Because I track my diet every day, I can investigate the correlation between my meat, eggs, and cheese intake with creatinine. I now have 8 blood tests that correspond to dietary data, and interestingly, there is a moderately strong correlation between my average daily beef+egg+cheese intake with creatinine (r = 0.55). Based on these data, I’m going to continue to minimize consumption of these foods, with the goal of optimizing mec intake

On a final note, I also expected to further reduce my CRP from 0.3 to something lower, but it slightly increased to 0.37 mg/L. While that is far from a high value, lower is better, and in future blood tests I’ll try to figure out how to further reduce it.

If you’re interested in calculating your biological age, here’s the Excel link:

DNAmPhenoAge_gen (1)


Quantifying Biological Age: Checklist

To make it easier to review the aging and all-cause mortality data for the circulating biomarkers that are contained within the biological age calculator, Phenotypic Age (see, here’s a checklist!

1. Albumin:

2. Creatinine:

3. Glucose:

4. C-reactive protein:

5. Lymphocyte %:

6. Mean corpuscular volume (MCV):

7. Red cell distribution width (RDW%):

8. Alkaline phosphatase:

9. White blood cells:


Optimizing Biologic Age: Lymphocyte %

The percentage of lymphocytes is one of the 9 blood test variables included in the biological age calculator, Phenotypic Age ( The reference range for lymphocyte % is 20 – 40% of the total amount of white blood cells (WBCs), but are higher or lower values optimal for health and longevity?

To answer that question, it’s important to know how levels of lymphocytes change during aging, and its association with risk of death for all causes. In one of the earliest studies to examine how the percentage of lymphocytes changes with age, Levine (2013) reported that lymphocyte % significantly decreased during aging in 9,389 adults (age range, 30 – 75y). However, the absolute values for these changes, i.e. from 40% to 30%, for ex., was not reported.

Similarly, lymphocyte % decreased during aging in a much larger study (377,686 subjects; age range, 18 – 85y; Wang et al. 2017):

Screen Shot 2019-11-16 at 9.38.37 AM

Interestingly, for women, lymphocyte % decreased from 27% to 21% from 20 – 35y, increased from 21% to 26% from 35 – 55y, then again decreased from 26% to 20% from 55y to 85y. In contrast, lymphocyte % more steadily decreased for men, from 28% to 17% from 20 – 85y.

Based on the aging data, higher values for lymphocyte % are are associated with biologic youth, whereas lower values are found in older adults. Although there are few studies that have investigated associations between lymphocyte % with aging or disease risk, in contrast, more studies have been published for absolute levels of lymphocytes.

In a small study of 106 older adults (> 85y) that were healthy (i.e. free of disease) at baseline, lymphocytes  less than 1.14*10^9 cells/L (equivalent to 1140*10^6 cells/L) was associated with an increased risk of death for all causes, when compared with 1850*10^6 cells/L (Izaks et al. 2003):

lympho mort

In a larger study (624 subjects), lymphocytes less than 1540*10^6 cells/L was associated with a significantly shorter average lifespan (~5y; 0.5 proportion remaining below), when compared with 1540 – 2040*10^6 cells/L . Also note that survival for the group that had 1540 – 2040*10^9 lymphocytes/L was not significantly different from the group that had more than 2040*10^9 lymphocytes/L (Leng et al. 2005):Screen Shot 2019-11-16 at 8.36.34 AM.png

In agreement with the smaller studies, lymphocytes < 1300 and < 1200*10^6 cells/L in women and men (red and blue, far left), respectively was associated with an increased all-cause mortality risk, when compared with average lymphocyte values ~1900*10^6 cells/L (decile 5) in a larger study that included 262,394 non-smokers (age range, 37 – 73y; Welsh et al. 2018):

Screen Shot 2019-10-08 at 7.26.51 AM

Collectively, these data suggest that higher values for lymphocyte % and for the absolute amount of lymphocytes may be optimal for minimizing disease risk and for maximizing longevity. If both are low, can they be raised? Circulating levels of lymphocytes are reduced during zinc deficiency (Fraker and King, 2001), so monitoring zinc intake, then increasing it to at least the RDA may be a first step towards increasing lymphocyte levels and %.

If you’re interested, please have a look at my book!


Fraker PJ, King LE. A distinct role for apoptosis in the changes in lymphopoiesis and myelopoiesis created by deficiencies in zincFASEB J. 2001 Dec;15(14):2572-8.

Izaks GJ, Remarque EJ, Becker SV, Westendorp RG. Lymphocyte count and mortality risk in older persons. The Leiden 85-Plus Study. J Am Geriatr Soc. 2003 Oct;51(10):1461-5.

Leng SX, Xue QL, Huang Y, Ferrucci L, Fried LP, Walston JD. Baseline total and specific differential white blood cell counts and 5-year all-cause mortality in community-dwelling older womenExp Gerontol. 2005 Dec;40(12):982-7.

Levine ME. Modeling the rate of senescence: can estimated biological age predict mortality more accurately than chronological age? J Gerontol A Biol Sci Med Sci. 2013 Jun;68(6):667-74. doi: 10.1093/gerona/gls233.

Wang Z, Li L, Glicksberg BS, Israel A, Dudley JT, Ma’ayan A. Predicting age by mining electronic medical records with deep learning characterizes differences between chronological and physiological ageJ Biomed Inform. 2017 Dec;76:59-68. doi: 10.1016/j.jbi.2017.11.003.

Welsh C, Welsh P, Mark PB, Celis-Morales CA, Lewsey J, Gray SR, Lyall DM, Iliodromiti S, Gill JMR, Pell J, Jhund PS, Sattar N. Association of Total and Differential Leukocyte Counts With Cardiovascular Disease and Mortality in the UK Biobank. Arterioscler Thromb Vasc Biol. 2018 Jun;38(6):1415-1423. doi: 10.1161/ATVBAHA.118.310945.