
Answer:
C15:0 fatty acid, also called pentadecanoic acid and found in the supplement fatty15, is a saturated fatty acid naturally present in dairy fat, ruminant meats (e.g., beef, bison, and lamb), and some fish and plants (Venn-Watson, PLoS One 2022). C15:0 fatty acid in fatty15 (which suggests taking one 100-mg capsule daily) is promoted for "healthier hair & skin, balanced metabolism, and deeper sleep," as well as "slowing the aging process" and "optimizing red blood cell production," but there are no clinical studies to support these uses.
Sign in as a member to learn if clinical research supports the use of C15:0 fatty acid supplementation for any other conditions, including cancer, type 2 diabetes, fatty liver disease, anemia, heart disease, heart failure, overweight/obesity, and risk of death, and learn how this supplement should be taken and possible side effects, and find out if this ingredient is worth the cost. Also, learn if you can safely get clinically relevant doses of C15:0 fatty acids from foods, and find out whether C15:0 is or is not essential or a suitable alternative to fish oil.
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elizabeth22473
April 08, 2025I was wondering if there is any connection between FATTY 15 and side effects with people who have had their gallbladder removed?
I had severe Gastro side effects until I discontinued FATTY 15.
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joseph22196
March 07, 2025Fatty15 is essential only for the company's bottom line selling this snake oil.
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T E21924
February 08, 2025Have no idea whether it's relevant, but I seem to have developed hepatic steatosis while taking Fatty 15. Could of course be a coincidence, but have reported as a potential adverse event, and hope that others will do likewise. What's good for dolphins is not necessarily good for humans!
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Michael21219
November 28, 2024I have taken C15: 0 (fatty 15) for 4 months. I began it because I started eating a vegan diet. Subjectively, I have not noticed any clear benefits or adverse effects. I have had a reduction in osteoarthritis pain, which is consistent with the reports on the vegan diet effect. My concern about C:15: 0 is that Dr. Venn-Watson seems to be the only expert in the field who considers it an "essential" nutrient.
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William20624
September 08, 2024Have been taking for over 9 months. Taking 2 a day for 6 months. My nails no longer split and my beard grows twice as fast. Cuts and wounds are healing faster. Nothing scientific, but at 63 years old I’ll take it
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Deanna20620
September 08, 2024I took two Fatty15 pills daily for 7 months and my cholesterol went down 44 points, from 280 to 236. I did not have any other changes to my diet nor lifestyle. Fatty15 may have been more beneficial to my body because I could be lacking it. I can't eat dairy and I rarely eat red meat. If someone is already getting Fatty15 in their food intake the supplement may not make a noticeable difference the way it did with me.
Lucinda Armacost
February 15, 2025Great news about lowering cholesterol
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Vin20619
September 08, 2024Fatty15 is often marketed as an alternative to Omega-3s. This is scientifically inaccurate. 'Take this instead of smelly fish oil,' is, I believe, how it was positioned. When I pointed this out to their customer service, they just argued back.
We appreciate you sharing your experience. We have updated our article to include a section explaining why we believe C15:0 fatty acids may not be an appropriate substitute for fish oil: https://www.consumerlab.com/answers/what-is-pentadecanoic-acid-and-does-it-have-health-benefits/pentadecanoic-acid/#alternative-to-fish-oil
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Frances20584
September 04, 2024I have been taking Fatty 15 for about 100 days. I will have some lab results soon and that will be interesting but until then I have noticed that my late afternoon hunger has decreased quite a bit. I am 59 and am struggling with several menopause symptoms, weight gain being one of them. I think it is helping me in this area and I have lost a little weight since going on it (4 lb). I also have high cholesterol and I will be interested to see if my labs have improved. Thanks for this report and for everyone’s comments - very helpful! I have no connection to Fatty 15, financially or otherwise - just a customer.
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Greg20517
August 27, 2024Are there any updates for Fatty 15? The company has stated that there are now double-blind placebo studies to support taking it. Personally, I took it for 18 months and saw no change in any blood markers or how I felt. I stopped taking in large part due to cost. I have no financial interest in product.
We've added information regarding a study (published in July 2024) that evaluated C15:0 fatty acid among adults that were overweight or obese. Details from that study can be found here: https://www.consumerlab.com/answers/what-is-pentadecanoic-acid-and-does-it-have-health-benefits/pentadecanoic-acid/#overweight
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Nan20410
August 17, 2024I recently subscribed to CL after an impulse purchase of C15. I had listened to a very compelling Utube by the woman that did initial research and I believe sells the supplement (significant conflict of interest). Your information and additional research resulted in cancellation of my subscription to the C15 company as well as returning the supplement unopened. Basically I just paid for my CL subscription with information provided here. I have no idea whether it would have worked for me but I like solid clinical backing of anything I take and this simply did not have it. Thank you.
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Joshua20159
July 22, 2024I don’t get it. Unsalted butter has 880mg per 100g, so that’s about 132mg per tablespoon. Why buy the expensive supplement?
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Vicky19413
May 03, 2024I took the Fatty 15 for 6 months and did blood work. My cholesterol level which was over 200 did drop 30 points. Not sure if my diet and working out contributed or the Fatty 15 truly helped. I wish there were more studies done.
Thank you for sharing your experience. Keep in mind that clinical evidence supporting a cholesterol-lowering benefit of pentadecanoic acid (the main ingredient in fatty15) is generally weak and mixed, as noted in the following section of our article: https://www.consumerlab.com/answers/what-is-pentadecanoic-acid-and-does-it-have-health-benefits/pentadecanoic-acid/#nafld
Nancy20626
September 09, 2024You can knock your LDL down quickly (in a month) by eating a cup of rolled oats per day and reducing dietary saturated fats.
Hi Nancy, see our Oat Cereals Review for our discussion of the amount of oats recommended to consume to help lower LDL cholesterol https://www.consumerlab.com/reviews/oat-based-cereals/oats/#background.
Ralf20908
October 19, 2024You might add the caveat that oats are glucose-spikers for many pre/diabetics.
Please see the following section of our Oat Cereals Review for information about which oat cereals are better options for helping to control blood sugar levels: https://www.consumerlab.com/reviews/oat-based-cereals/oats/#oat-cereals-for-managing-blood-sugar
James21619
January 11, 2025Also keep in mind that Oats, unless Organic, are often heavily sprayed with Glycosphate. Ditto the Glycemic effect. I am not diabetic and my HOMA IR is less than 1 but while using a CGM for 3 months I noticed a significant glucose spike with oatmeal. (Before I learned about the Glycosphate)
We include information about glyphosate in oat products in the following section of our Oats Review: https://www.consumerlab.com/reviews/oat-based-cereals/oats/#glyphosate
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Cheryl19373
April 23, 2024I took fatty15 for about 6 weeks. I was becoming increasingly pale and was experiencing stomach upset and daily diarrhea. And in general not feeling very well. The only thing that has changed is my addition of the fatty 15 supplement. I have been off of them for about 2 weeks and not feeling any better yet. I am wondering if it takes a while for fatty 15 to clear out of your body??
Lucinda Armacost
January 24, 2025Also I am sluggish and not feeling well. Taking just one in am. Oat bran products and zero cholesterol dairy
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ANDREA18303
January 05, 2024I have been taking Fatty 15 for a little over 9 months and at about 3 months in, I noticed I was having vivid dreams almost every night. So I decided to continue taking it. The dreams have continued. More recently (after about 6 months) I realized that my nails, which had always been very brittle, are now hard and no longer split. I have also been able to grow them much longer than before. I haven't had any blood work done since I started using F15 but have this scheduled for next month, which will be around my anniversary date of taking them. I will be interested in seeing those results. Per the posting guidelines, I confirm I do not work for this company, I pay quarterly for a 90 day supply of the product and the above is my personal experience.
Thank you for sharing your experience, although we are not aware of any clinical research confirming a benefit of fatty15 for nail health.
Nancy20290
August 02, 2024Updates after bloodwork? I’ve been taking for only 3 days, but have already noticed a big increase in vivid dreams. Nothing else yet…
No ties to company, financial or otherwise.
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K M
January 05, 2024Conflict of interest: Stephanie Venn-Watson has decided that "C15:0 is an essential fatty acid ..." and also markets it at a very high price.
According to the National Academies of Sciences, there are currently only two recognized essential fatty acids: Linoleic Acid and a-Linolenic Acid.
Great point! We've noted this in the following section of our article: https://www.consumerlab.com/answers/what-is-pentadecanoic-acid-and-does-it-have-health-benefits/pentadecanoic-acid/#is-it-essential
eric20260
July 30, 2024Thank you for sharing conflict of interest about Stephanie! In our zeal we tend to forget such important point
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MICHAEL18299
January 05, 2024What are your thoughts on oral administration regarding taking with or without food - is the crystalline form of this fatty acid water soluble? Fat soluble? The company states "take with or without food" but one method must have better absorption..
Great question! We've added information about this to the following section of our article: https://www.consumerlab.com/answers/what-is-pentadecanoic-acid-and-does-it-have-health-benefits/pentadecanoic-acid/#how-to-take
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Craig18297
December 24, 2023Thanks for this sober assessment. I was looking into it for my mother. The supplement is only a 100 mg per daily capsule and there is no RDA data on it as a EFA. What I haven’t been able to find is any data on the actual amount found in food sources. A 100 mg seems to be a fairly small amount so question is do the trace amounts make it easy to reach this amount daily if one simply chooses certain foods. That would be really helpful if you are able to find any relevant data. The researchers seemed to have just jumped from cell culture studies to starting a supplement company rather than examine dietary sources.
We've added information about getting C15:0 fatty acid from food in the following section of our article: https://www.consumerlab.com/answers/what-is-pentadecanoic-acid-and-does-it-have-health-benefits/pentadecanoic-acid/#amount-in-food
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Richard18295
December 22, 2023Does soymilk normally contain C:15.0 or was it supplemented in the Chinese study?
C15:0 was added to soymilk in the Chooi study. Soymilk alone is not a significant source of C15:0 fatty acid (https://fdc.nal.usda.gov/fdc-app.html#/food-details/2340784/nutrients).
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john18293
December 05, 2023Are there any reports on fatty 15 helping lung fibrosis?
We are not aware of any studies evaluating pentadecanoic acid for lung fibrosis.
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Robert18292
November 29, 2023I have been taking for 90 days and don’t notice any differences. Perhaps already being relatively healthy at 60 and not taking any medications is a factor. In fact none of the nutritionals I take make a measurable difference in the absence of blood testing daily to see.
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LYNN18288
November 10, 2023I've taken Fatty 15 for 8 months, but see no difference in sleep quality, A1C results, energy. I won't buy more.
Pete20125
July 19, 2024I frankly wouldn't expect to feel magically different from using such a product. Ultimately we need to see clinical studies and then do testing to verify whatever results the studies indicate.
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Stan18286
November 07, 2023I see that the label states that this product is “essential” for replenishing and strengthening cells. OMG, how in the world have I survived for so long without it!!
James18287
November 29, 2023This ConsumerLab articles notes that C15:0 is present in our diets in small amounts. In her paper, “Efficacy of dietary odd-chain saturated fatty acid pentadecanoic acid parallels broad associated health benefits in humans: could it be essential?,” Stephanie Venn-Watson et al., Scientific Reports volume 10, she also states that we have been consuming less in recent years.
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George18285
November 07, 2023I have been on a Fatty 15 for a little over a month and have noticed some slight improvements in how I feel. But that can obviously be just a placebo effect. Two years ago I had a quadruple bypass & aortic aneurysm open heart procedure, and now I am just dealing with the side effects of drugs from that and upper respiratory challenges. It is all a part of being 80!
However, I am convinced I don't need to feel this bad, and I plan to feel better. I appreciate your review of Fatty 15.
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