In an earlier post (https://michaellustgarten.com/2018/06/26/maximizing-health-and-lifespan-is-calorie-restriction-essential/), I documented my aging.ai 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 (https://michaellustgarten.com/2019/09/09/quantifying-biological-age/). 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 (https://michaellustgarten.com/2019/09/09/quantifying-biological-age/). 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 https://michaellustgarten.com/2019/09/09/quantifying-biological-age/). 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 (https://michaellustgarten.com/2019/09/09/quantifying-biological-age). 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 (https://michaellustgarten.com/2015/08/13/blood-testing-whats-optimal-for-wbc-levels/). However, within WBCs, neutrophils increase, […]

Alkaline phosphatase (ALP) is one of the 10 variables used to quantify biological age with PhenoAge (https://michaellustgarten.com/2019/09/09/quantifying-biological-age). The reference range for alkaline phosphatase is 20 – 140 IU/L*, but within that range, what’s optimal? Two separate meta-analyses have investigated the association between serum levels of ALP with risk of death […]