The Groundbreaking Discovery & New Science Validating C15:0 as an Essential Fatty Acid

Excitedly, a slew of new peer-reviewed papers are further validating C15:0 (pentadecanoic acid) as the first essential fatty acid to be discovered in more than 90 years. In addition to the original studies published in 2020 by Venn-Watson et al., two independent teams using cell-based studies, extensive literature reviews, and gold standard dietary deficiency studies are reconfirming C15:0 as an essential fatty acid. 

Additionally, studies have demonstrated that moms with higher C15:0 have children with improved body growth and cognitive development. Understanding that pure C15:0 has key activities (like strengthening our cells, activating AMPK and PPARs, and inhibiting mTOR and JAK-STAT) that are essential to maintaining health throughout our lives, C15:0 supplementation with fatty15 is offering an optimized solution to slow aging and truly help us all live healthier, longer.

While the term “essential” is frequently thrown around (like, essential oils, essential skin care, essential supplements), the term essential fatty acid actually has strict criteria, which explains why there are only three known essential fatty acids today.

In this article, we cover: 1) the criteria for essential fatty acids, 2) the recent discovery of C15:0 (pentadecanoic acid) as the third-ever discovered essential fatty acid, and 3) what makes C15:0 so darn essential - including how nutritional C15:0 deficiency accelerates aging and may be affecting as many as 1 in 3 of us. 

Okay, what is an essential fatty acid?

Good question. An essential fatty acid (EFA) is a nutrient that our bodies must have to maintain our baseline physiological health. Since our bodies don’t make enough of these essential fats, we must get adequate amounts routinely from our diet or supplements. 

Here’s a fun fact: This definition is the same criteria for vitamins, which is why the first two discovered essential fatty acids were initially called “Vitamin F”.

There are only three known essential fatty acids:

• Linoleic acid (an omega-6 fatty acid)
• Alpha-linolenic acid (an omega-3 fatty acid)
• C15:0 (pentadecanoic acid, an odd-chain saturated fatty acid)

While the omegas were found to be essential fatty acids between 1929 and 1931, C15:0 was not detailed as an essential fatty acid until 2020.

Well, that’s exciting! But what is C15:0?

C15:0 is a dietary odd-chain saturated fatty acid. Odd-chain because it has 15 carbons. Saturated because it has no double bonds. In contrast, omega fatty acids are polyunsaturated fatty acids, which means they have multiple double bonds. 

So, how does one know that an essential fatty acid is truly essential?

Fatty acids are truly essential if they meet all of the following criteria:

• Low levels of the nutrient result in a nutritional deficiency syndrome.
• Our body cannot make adequate amounts of this nutrient on its own.
• Maintaining adequate levels is dependent on eating foods or supplements containing the nutrient.
• The nutrient prevents, manages, treats, and cures the nutritional deficiency syndrome.
• There is evidence of an active metabolite, which is a molecule that our body makes using the nutrient, that has different but complementary health benefits.

That’s a hefty must-do list. Which explains why only three essential fatty acids have been discovered. So, let’s cover how C15:0 meets these criteria. 

Criteria #1: Low C15:0 levels result in a nutritional deficiency syndrome.

As an essential fatty acid, C15:0 does a lot of good things. One of its primary roles, however, is to physically strengthen our cell membranes against lipid peroxidation. How does C15:0 strengthen our cells? Well, it has no double bonds, which makes it highly resistant to lipid peroxidation. This is important because lipid peroxidation is a big-time driver of aging. Aging cells, and aging us.

C15:0 is so important to strengthening our cell membranes, that if we have low C15:0 levels (defined as < 0.2% of total fatty acids), our cells become fragile and result in Cellular Fragility Syndrome. This syndrome involves a newly discovered form of cell death, called ferroptosis, which accelerates aging and impairs our long-term metabolic, heart, liver and red blood cell health.

As many as 1 in 3 people have C15:0 deficiency and are susceptible to Cellular Fragility Syndrome.

Criteria #2: Our body cannot make adequate amounts of C15:0 on its own.

While our body can make some amounts of C15:0 to achieve C15:0 levels of around 0.1% total fatty acids, it cannot make enough to maintain adequate C15:0 levels that reliably protect against Cellular Fragility Syndrome. As a reminder, we need > 0.2% C15:0 to avoid nutritional deficiency.

Criteria #3: Maintaining adequate C15:0 levels is dependent on eating foods or supplements containing C15:0.

By far, our most reliable dietary source of C15:0 is from dairy fat. In fact, C15:0 blood levels have been used for decades to measure how much dairy fat a person eats. While C15:0 is present in some types of meat, fish, and plants, none of these foods reliably influence our C15:0 levels. 

More recently, two clinical trials have shown that C15:0 supplementation also directly increases C15:0 levels. For every 100 mg of supplementation with pure C15:0, our C15:0 body levels increase about 0.1%. That means most people need 100-200 mg of daily C15:0 to avoid nutritional deficiency.

Criteria #4: C15:0 prevents, manages, treats, and cures the defined nutritional deficiency syndrome.

Cellular Fragility Syndrome involves a distinct combination of events that accelerate aging and impair our long-term health, including the following:

• Low C15:0 results in fragile cell membranes.
• These fragile cell membranes undergo lipid peroxidation.
• Fragile red blood cells are engulfed by the liver, resulting in iron overload (a condition called dysmetabolic iron overload syndrome, or DIOS).
• Unwanted iron combines with lipid peroxidation in cells, resulting in mass production of reactive oxygen species (ROS).
• Damaging ROS kills mitochondria in the cells, resulting in cell death (aka, ferroptosis).
• Ferroptosis throughout our bodies impair our metabolic, heart, liver, and red blood cell health.

Peer-reviewed studies have shown that C15:0 supplementation successfully reverses and treats all key components of Cellular Fragility Syndrome, including raising C15:0 levels, lowering lipid peroxidation, strengthening red blood cells, stopping liver iron deposition, lowering ROS, and repairing mitochondria in relevant models.

Further, human clinical trials have shown that C15:0 supplementation raises C15:0 levels, resulting in improved red blood cell health, improved liver function, lower LDL cholesterol, and improved gut health within 12 weeks. All these studies help to explain why people with higher C15:0 have healthier long-term metabolic, liver, heart and red blood cell health.

Thus, there is substantial evidence not only that C15:0 deficiency causes Cellular Fragility Syndrome, but that restoring C15:0 treats this condition.

Criteria #5: There is evidence of an active metabolite, which is a molecule that our body makes using the C15:0, that has different but complementary health benefits.

Indeed, Venn-Watson et al. discovered that our body uses C15:0 to make a second molecule, called pentadecanoylcarnitine (aka PDC). Impressively, PDC fully activates the endocannabinoid system, including CB1 and CB2 receptors, which are responsible for deeper sleep, calmer mood, and less pain. Fun fact: PDC is the second-ever discovered fully acting endocannabinoid. 

The take home message

So, there you have it. Peer-reviewed studies continue to emerge, which repeatedly support C15:0 as a once-in-century discovery of a new essential fatty acid. Importantly, while C15:0 deficiencies are likely highly prevalent globally (resulting in accelerated aging and impaired metabolic, heart, liver and red blood cell health), we have an opportunity to easily fix these conditions by getting essential C15:0 back into our lives.

While adding whole fat dairy back into diets, especially for children, can help fix nutritional deficiencies, the ability for dietary C15:0 to support adult health is complicated by much higher levels of competing proinflammatory saturated fats present in dairy fats. 

As such, Dr. Venn-Watson and her Navy physician husband, Eric, have worked collaboratively with the U.S. Navy for the past decade to optimize C15:0 as a pure, bioavailable, patented, and vegan-friendly ingredient in fatty15 that provides just the good C15:0 fat and directly taps into core age-slowing mechanisms to help us live healthier, longer.

Read the Science

Discover15.com

Read the Simon & Schuster Book

The Longevity Nutrient, by Dr. Stephanie Venn-Watson