Have a look at my latest book update, including ~50 references that link microbial burden with all of the Hallmarks of Aging! Advertisements


Many interventions have been reported to increase NAD levels, but dietary components that can impact NAD levels are less discussed. Here, I highlight the ability of two dietary components, apigenin and quercetin to increase NAD, and report the foods that contain these metabolites.

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, […]

Measurement of biological age with Levine’s Phenotypic Age calculator is strongly correlated with chronological age (r=0.94; see In 2019, I measured all 9 of its analytes 3 times, with biological age readings of 35.39y, 35.58y, and 31.3y, for an average 2019 biological age of 34.09y (see That’s 12 […]

Here’s a link to a recent interview, Including: How (and why) did you get involved in research in aging and the human microbiome? How did you get started in health optimization /  quantified-self? What are your thoughts on biological age testing? Which tests (epigenetic, blood biomarkers, telomere, etc) and […]

In earlier posts, I reported year-over-year improvements for my resting heart rate (RHR), from 51.5 (bpm) when I first started tracking in August 2018 to 48 bpm in November 2019 ( Did my year-over-year RHR improvement continue in December 2019? As shown below, in December 2018, my average RHR was […]

Besides diet (, are there other factors that may impact epigenetic aging? First, let’s have a look at clinically relevant variables, including inflammation, the lipid profile, kidney function, blood pressure, and body size/dimensions (Liu et al. 2019): One of the strongest correlations for the clinical variables with epigenetic aging (AgeAccelGrim) […]

Creatinine is one of the 9 blood test variables included on the biological age calculator, Phenotypic Age ( The reference range for women and men is 0.5 – 1.1, and 0.6 – 1.2 mg/dL respectively, but within that range, what’s optimal for health and longevity? To answer that question, it’s […]

My average biological age in 2019 is 12 years younger than my chronological age (46y) based on the Phenotypic Age calculator (, and 16y younger based on ( One factor that likely contributes to my relatively youthful biological age is my diet. Shown below is my average daily dietary […]

In an earlier post (, I documented my biologic age for 13 blood test measurements from 2016 – 2019. If you missed that post, here are those data: Note that note my average biologic age has slowly increased from 2016 to 2019, from 28y in 2016 (2 measurements), to […]

On June 10, 2019 (for the first time) I measured all of the blood test variables that are included in the biologic age calculator, Phenotypic Age, and ended up with a biological age = 35.39y ( While that value is 23% younger than my chronological age (46y), I knew that […]

The coronary artery calcification (CAC) score is a measure of how much calcification is in the coronary arteries, and accordingly, is an in vivo measure of atherosclerosis. Why is the CAC score important? Besides its role in atherosclerosis, risk of death for all causes goes up at any age as the […]

High sensitivity C-Reactive Protein (CRP) is one of the 10 variables included in the biological age calculator, PhenoAge ( The reference range for CRP is 0 – 3 mg/L, but within that range, what’s optimal? To answer that question, it’s important to know how CRP changes during aging, and what […]

Mean corpuscular volume (MCV) is one of the 10 variables included in the biological age calculator, PhenoAge (see It’s calculated by dividing the fraction of the blood that contains RBCs (hematocrit) by RBCs (MCV = hematocrit/RBC), thereby identifying the average volume contained within red blood cells. Although the MCV reference […]

Circulating levels of white blood cells (WBCs) are one of the 10 variables used to quantify biological age with PhenoAge ( The reference range for WBCs is 4.5 – 11 *10^9 cells/L, but within that range, what’s optimal? Several studies have reported that WBCs greater than 5 are associated with an […]

In an earlier post, based on data from the Baltimore Longitidunal Study on Aging (BLSA), I suggested that total white blood cell (WBCs) counts between 3500 to 6000 cells per microliter of blood may be optimal for reducing disease risk and for maximizing longevity ( However, within WBCs, neutrophils increase, […]