C15:0: what the evidence currently shows, and what it does not

C15:0, or pentadecanoic acid, is an odd-chain saturated fatty acid from dairy fat and some fish. Higher blood levels track with better cardiometabolic and liver markers in observational studies. Supplement makers advise up to 300 mg daily. No human trial yet shows that supplementing it prevents disease or extends lifespan.

Key points

• C15:0 is an odd-chain saturated fatty acid found in dairy fat and certain marine foods.
• Evidence is observational, animal and cell-based, not outcome trials in humans.
• Typical supplemental intake is up to 300 mg daily of 99%+ pure pentadecanoic acid.
• It is not a treatment for liver disease, diabetes, cancer or cardiovascular disease.
• Pregnancy, cancer treatment, liver disease or polypharmacy warrant a physician review first.

Not every saturated fat behaves in the same biological way.

C15:0, also known as pentadecanoic acid, is an odd-chain saturated fatty acid found naturally in small amounts in dairy fat and certain fish. It is currently being studied for its role in cell-membrane structure and metabolic signalling.

The science is promising, but it is still emerging. C15:0 should not be presented as a treatment for cancer, diabetes, liver disease, cardiovascular disease or any other medical condition. Associations and laboratory findings are not the same as proven clinical outcomes.

What makes C15:0 scientifically interesting is its structural role. Cell membranes are not passive barriers. They influence how cells communicate, respond to stress and maintain stability. C15:0 is incorporated into lipid structures and may contribute to membrane integrity and signalling pathways relevant to metabolic health.

What does the evidence currently suggest?

Higher circulating C15:0 levels have been associated in observational research with more favourable cardiometabolic and liver-health markers. Laboratory and early translational studies have also examined metabolic signalling pathways such as AMPK and mTOR.

However, associations do not prove that supplementation prevents disease or extends lifespan. High-quality, independent, long-term human trials remain necessary.

How much C15:0 should I take per day?

For pure C15:0, dose discipline matters.

Hansen Supplements specifies that its C15:0 product contains 99%+ pure pentadecanoic acid and recommends a daily intake of up to 0.3 g, or 300 mg, daily. The product is supplied with a dedicated measuring spoon intended to support accurate dosing.

From a clinical perspective, a sensible approach is:

• Start with 100 mg daily with a meal
• Review tolerance over one to two weeks
• Increase only where appropriate, without exceeding 300 mg daily unless specifically advised by a physician

C15:0 is not a replacement for dietary quality. A longevity-oriented nutrition plan should still prioritise adequate protein, fibre, vegetables, legumes, healthy fats, micronutrients and metabolic health markers.

Who should speak with a physician first?

Anyone who is pregnant or breastfeeding, undergoing cancer treatment, living with liver disease, managing diabetes, taking lipid-lowering treatment, or using multiple medications should speak with a physician before introducing C15:0.

This is especially important because C15:0 research is evolving and because an individual longevity protocol should be based on the person's full metabolic profile, laboratory data, medication list and health priorities.

Is C15:0 worth taking right now?

C15:0 sits at the intersection of nutrition, membrane biology and metabolic signalling, which is why it is studied. That is a reason for interest, not a reason to expect an outcome.

Nothing is claimed for it here. The strongest protocol remains the one that is measured, personalised and clinically monitored.

Complimentary visitor resource: Download our Longevity Supplement Decision Framework to assess whether a supplement has a clear purpose, appropriate dose, relevant monitoring plan and acceptable interaction profile before adding it to your routine.

Reviewed by Dr. Erietta Galani, MD, PhD in cellular immunology, dual specialty in internal medicine and intensive care, Founder and Medical Lead, minus10med, Athens.
Last reviewed: 11 August 2026

This article is educational and does not replace individual medical advice, diagnosis or treatment.