Fatty 15 Review: All The Details On The Newly Discovered Essential Fatty Acid



Fatty 15 is a once daily oral supplement made with the recently discovered essential fatty acid, C15:0, also known as pentadecanoic acid. Interestingly, this is the first essential fatty acid to be discovered since omega-3, which was over 90 years ago!

Fatty 15 promises a range of benefits, such as strengthening cell membranes, keeping mitochondria working, and naturally activating receptors throughout your body and brain to regulate immunity, metabolism, mood, appetite, and sleep.

So does Fatty 15 really work? To answer that question, we’ll thoroughly review the product formulation based on what the current medical research has found about the effects of C15:0 supplements. 

We’ll also share some Fatty 15 reviews from real customers so that you can get their take on the results of this supplement. 

What Are The Fatty 15 Ingredients?

The Fatty15 supplement contains just one ingredient: pure pentadecanoic acid (C15:0).

C15:0 is an odd-chain saturated fatty acid. Dr. Steph Venn-Watson, one of the Fatty 15 co-founders, discovered that C15:0 is not only a good fat, but that it’s an essential fatty acid — a type of fat that the body cannot produce on its own and must be obtained from dietary sources. 

Our primary food-based source of C15:0 is whole fat cow’s milk, which contains trace amounts of C15:0. 

One problem is that food-based C15:0 is tied up in complex lipids called triacylglycerides, which the body cannot absorb. Because of this, digestive enzymes are needed to break C15:0 down into free fatty acids, which can then be absorbed.

Fatty 15 was created to provide the body with ready-to-absorb free fatty acid C15:0. So how does C15:0 affect the body? 

In extensive peer-reviewed studies, C15:0 has been shown to support metabolic, heart, liver and immune health, as well as naturally activate receptors in our bodies that deepen sleep, reduce anxiety, and improve joint comfort.

For example, a 2022 publication in the journal PLOS ONE states that there’s evidence to support C15:0’s role as an emerging essential fatty acid relevant to both physical and mental health. The publication also states that C15:0 has anti-cancer and antimicrobial properties, and has the potential to help manage depression and autoimmune diseases.

In another study, published in the journal Scientific Reports, the authors demonstrate that C15:0 mitigates inflammation, anemia, dyslipidemia, and fibrosis in vivo, possibly through its interaction with critical metabolic regulators and repairing mitochondrial function.

What’s great about pentadecanoic acid (C15:0) is that since it’s a saturated fat it is very stable and less susceptible to oxidation. 

This in contrast to omega-3 fats that have multiple double bonds, which makes them unstable and highly susceptible to oxidation. 

In fact, a study published in the peer-reviewed journal Nutrition states, “Many commercially available omega-3 supplements are unacceptably oxidized, leading to myriad potential health risks.”

What Are The Benefits of Fatty 15?

After reviewing the literature on C15:0, we’ve summarized the benefits that Fatty 15 may offer:

Balanced Metabolism

Fatty15 may help to rebalance the metabolism naturally by turning on important metabolism controllers called PPAR-alpha and delta receptors, controlling glucose levels through AMPK pathways, and fixing our cell engines (mitochondria) so they can make energy properly.

Better Liver Health

Fatty15 supports your liver health at the cellular level. Numerous studies have shown that both adults and children with higher C15:0 levels have better liver health. 

Beyond association, Fatty15 is as a PPAR-ɑ/δ agonist, supporting liver health by enhancing cell membrane resilience, reducing immune responses, and slowing the formation of harmful liver tissue.

Improved Skin and Hair Health

Based on the Fatty 15 reviews that we read, numerous customers have experienced improvements in their skin and hair from taking this supplement. 

It works by strengthening cell walls, which is important because your cells’ protective membranes can become weak as you age (this is one reason skin begins to feel less elastic and firm). C15:0 gets into cell walls and keeps them sturdy, protecting them from external stressors.

What Are The Fatty 15 Side Effects?

Like any dietary supplement, there is a possibility of experiencing side effects, but that possibility seems to be pretty low with Fatty 15. 

On the brand’s website, they share that over 77,000 customers have taken the Fatty 15 supplement with very few side effects. Furthermore, they state that the following side effects have been reported in less than 0.1% of customers: constipation, diarrhea or headache.

Always consult with your healthcare provider before incorporating any supplements into your routine to ensure they align with your individual health needs and medical conditions.

Where to Buy The Fatty 15 Supplement?

The Fatty 15 supplement is sold exclusively on the brand’s website ( 

How Much is Fatty 15?

Fatty 15 costs $49.95 USD for one bottle of 30 capsules (30 day supply)

Our Verdict

Overall, we think that Fatty 15 is an innovative supplement with considerable potential. Yet, given its recent discovery, rigorous clinical trials are essential to assess its long-term efficacy and safety profile.


  • May provide benefits to the whole body, including metabolism, liver, skin, hair, and more
  • Many positive Fatty 15 reviews
  • 30 day money back guarantee
  • Unlikely to cause side effects


  • As a newly discovered supplement, there may be limited scientific evidence regarding its long-term effects and safety

What Are Some Alternatives to Fatty 15?

Since pentadecanoic acid is a recently discovered essential fatty acid, at the time of writing this review there aren’t any other C15 supplements on the market. 

If you’re looking for a supplement that supports the skin, hair, nails, joints, and gut, check out our oral collagen supplement reviews, such as:

PLoS One. 2022; 17(5): e0268778.
Sci Rep. 2020 May 18;10(1):8161.
Nutrition. 2019 Apr:60:74-79.



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