C15:0 and Heart Health - Advancing from Association to Causation

December 14, 2025

Welcome to Issue 159 of Science Says! Our weekly newsletter where you’ll learn the latest healthy aging and C15:0 research news that our team of doctors, scientists, and experts are most excited about—without having to go search for it.

Eric and Steph
Co-Founders, Doctors, Nerds

What Dr. Stephanie Venn-Watson, our co-founder and author of The Longevity Nutrient and over 80 peer-reviewed scientific publications, is reading.

Healthy Aging

Growing Evidence Around C15:0 & Healthy Hearts

Throughout 2025, an increasing number of peer-reviewed studies associated higher C15:0 levels with better long-term heart health. To add to that list (right under the wire for 2025), a pre-print from the prestigious medical journal, BMC Medicine, was recently released showing that C15:0 directly lowered ApoB and ApoE in a preclinical model, which may help explain how C15:0 may be playing an active role in keeping our hearts (and us) healthy.

Sounds great, but what’s ApoB and ApoE?

Apolipoproteins are proteins that bind to fats, including cholesterol, and help direct these lipids into doing good or bad things in our body.

There are different types of apolipoproteins, such ApoA, ApoB, and ApoE. While there are even different subtypes of apolipoproteins within these categories (aka, ApoA1, ApoE4 and so on), the main point here is that:

ApoA1 is part of “good” HDL cholesterol and is linked to better long-term heart health.
ApoB is part of “bad” LDL cholesterol and, as reviewed by Boren et al., is a driving factor for arterial plaques and poorer long-term heart health.
ApoE, as summarized by Rasmussen et al., is involved in imbalanced lipid metabolism, poor vascular function, and aging-related cognitive decline.

Apolipoproteins have become so valuable as biomarkers of cardiovascular health, that they are now often included in the blood panels we get during our routine checkups. In general, we want to see higher ApoA1 and lower ApoB and ApoE.

It is worth noting that sometimes folks also refer to ApoA, ApoB, and ApoE as the genes that influence the production of lipoproteins. Today, we’re talking about the actual lipoproteins in the blood (not the genes).

Got it. What did this latest study look at, and what did it show?

Chen et al. used proteomics to compare 1,368 circulating proteins that were detected among the following three study groups:

Mice fed no C15:0 (control group)
Mice fed low-dose C15:0
Mice fed high-dose C15:0

While they evaluated a lot of C15:0 benefits in this study, one key finding was significantly lower apolipoprotein B (ApoB) and apolioprotein E (ApoE) in mice that were fed either low- or high-dose C15:0 compared to non-C15:0 fed controls.

Thus, this study showed that C15:0 could actively lower both ApoB and ApoE within 12 weeks better than controls in this preclinical model.

How this study contributes to the growing evidence that C15:0 protects long-term cardiovascular health.

This study provides another piece of evidence, specifically how C15:0 works, to support the growing number of studies linking C15:0 to long-term heart health.

The building science on C15:0 and heart health

Whether it’s population-based studies, dose-dependent mechanisms of action, in vivo studies, or randomized controlled clinical trials, multiple studies from independent teams increasingly support that C15:0 is good for our long-term health, including our hearts.

Both Huang et al. and Chen et al. showed that the higher the C15:0 levels (> 0.2% total fatty acids), the healthier the associated blood pressure health – for both children and adults.
Meta-analyses of prospective cohort studies from Trieu et al. and Li et. al. demonstrated similar incremental associations: the higher the C15:0 levels, the better the associated long-term cardiovascular health.
Directly relevant to the latest Cheng et al. study, Zheng et al. found that people with higher C15:0 had associated lower ApoB levels, as well as lower total cholesterol.
Beyond association, multiple preclinical models fed C15:0 have lower total cholesterol levels compared to non-C15:0 fed controls; and C15:0 has direct dose-dependent protective effects on primary human vascular cell systems, including calming immune responses.
These health benefits may be due to C15:0’s demonstrated ability to activate AMPK and PPARɑ, which have been shown to support healthy cholesterol levels.
Further, controlled clinical trials from Arghavani et al. and Chooi et al. showed that increased intake of C15:0 results in increased C15:0 levels – and associated improvements in vascular function and lowered LDL-cholesterol.