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Free standard deliveryFatty15 30 Day Refill

Fatty15

30 Day Refill

£140.00

Fatty15 is a daily supplement built around C15:0, also known as pentadecanoic acid — an odd-chain saturated fatty acid that has attracted genuine scientific interest over the past several years.

  • Supports cellular membrane strength and integrity
  • Studied for long-term metabolic health markers
  • May support mitochondrial function at a cellular level
  • Simple one-capsule daily dose for easy adherence
  • Refill format for established Fatty15 users
4.8(12 reflections)
1

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Fatty1530 Day Refill
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About This Product.

Fatty15 is a daily supplement built around C15:0, also known as pentadecanoic acid — an odd-chain saturated fatty acid that has attracted genuine scientific interest over the past several years. Unlike the more familiar omega-3s or omega-6s, C15:0 is an odd-chain fat, and emerging research suggests it may support cellular membrane integrity, mitochondrial function, and metabolic balance. The 30 Day Refill is designed for existing Fatty15 users who want to maintain their supply without repurchasing the starter kit.

C15:0 is the kind of nutrient that tends to be low in people eating less full-fat dairy, and research into its role in long-term metabolic and cellular health is ongoing. It is studied for its potential to reduce cellular fragility, support red blood cell function, and contribute to broader metabolic markers — areas relevant to anyone paying close attention to their long-term health, not just those managing a specific deficiency.

This refill suits people who have already incorporated Fatty15 into a daily routine and want a consistent, unfussy supply. One capsule a day keeps the commitment minimal. Fatty15 as a brand has been notably research-led since its founding, with its science emerging from work originally conducted for the US Navy. That pedigree sets it apart from the majority of fatty acid supplements on the market, where the evidence base is considerably thinner.

C15:0 (Pentadecanoic Acid)

30 Day Refill

How to Take It

i.

Take one capsule daily. Follow any additional guidance on the packaging. Taking it with a meal is a reasonable habit, as fat-soluble nutrients are generally better absorbed alongside dietary fat.

Frequently Asked.

What is C15:0 and why does it matter?

C15:0, or pentadecanoic acid, is an odd-chain saturated fatty acid found primarily in full-fat dairy. It has been studied for its potential role in supporting cellular membrane stability, mitochondrial function, and metabolic health — areas that most standard supplement ranges do not address directly.

Who is this refill suitable for?

It is intended for people already using Fatty15 who want to continue their supply. If you eat very little full-fat dairy, your dietary C15:0 intake is likely low, which is the population the research has tended to focus on.

How long before I might notice a difference?

C15:0 is a nutrient you build up over time rather than something with an immediate acute effect. Most research looks at markers over weeks to months, so consistency matters more than timing.

Is this safe to take alongside other supplements?

C15:0 is a fatty acid rather than a pharmacologically active compound, so interactions with common supplements are not a known concern. That said, if you are on prescription medication — particularly lipid-related therapies — it is worth checking with your GP before adding any new fatty acid supplement.

Why buy the refill rather than the starter kit?

The refill is designed for those who already have the Fatty15 capsule format and simply need to top up their monthly supply. Check the packaging to confirm capsule count and any differences from the starter kit.

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Customer Reflections

Overall Sentiment

4.812 reflections
1 – 6 of 12 reflections
CB

Quietly consistent — that's the point

5 months ago

Been on this for about seven months now and the refill packaging makes it easy to just keep going. I switched to a lower-dairy diet a couple of years ago and started wondering what I might be missing. Hard to attribute specific changes to one supplement, but I feel like my energy baseline has been steadier. One capsule a day is genuinely no effort.

T

Solid science, minimal faff

5 months ago

I do my homework before adding anything to my stack. The research behind C15:0 is actually interesting — not the usual vague marketing claims. Happy to keep reordering the refill once I'd finished the starter kit.

SO

Good supplement, steep price

5 months ago

I believe in the science here and I've been taking it daily for four months. My only hesitation is the cost — £119.99 for a 30-day refill is hard to swallow (pun intended). Would love a subscription discount that brought it down a bit. Still reordering, but I do wince at checkout.

MT

6 months ago

Reordered three times now. Fits neatly into my morning routine alongside magnesium and vitamin D. No complaints.

PM

Finally a fatty acid supplement with actual backing

6 months ago

I'd been taking fish oil for years more out of habit than anything else. A friend who works in nutrition mentioned C15:0 and I spent a good week reading papers before committing. The fact that this came out of serious research rather than a wellness trend was what convinced me. Six months in and I've made it a permanent fixture.

JW

Does what it says on the tin

7 months ago

Subtle stuff — you won't notice a dramatic change overnight. But after a few months I felt my energy was more stable and my sleep felt more restful. Could be coincidence, but I'm not stopping. Refill process is seamless.

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