Dr Dinuk Dissanayake, former NHS gut doctor and founder

6 Reasons I Created My Own Collagen After 25 Years as an NHS Doctor (And Why I Recommend It to Women Over 40)

Collagen is one of the hottest wellness trends for improving your skin, hair and joints.

But whether it actually does anything depends on the science behind the formulation of the product you choose. Here’s how I made mine.

10,000mg marine collagen peptides a day
No flavours, sweeteners or additives
90-day money-back guarantee

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Rated 4.8 out of 5 by thousands of customers

Dr Dinuk · why I made Correxiko

Over 1 million products soldDoctor-formulatedIndependently testedSince 2012

Over 1 million products sold
Doctor-formulated
Independently tested
Since 2012

As featured in

The six reasons, in short

1 It supports the places where ageing shows first
2 I was tired of collagen that was under dosed
3 Marine over Bovine: what they don’t tell you that a doctor will
4 Most collagen isn’t designed for your body to absorb easily
5 Your collagen shouldn’t taste like a chocolate milkshake
6 I made the collagen I’d give my own wife, daughters and patients

01
It supports the places where ageing shows first

Duller skin, finer hair and stiffer joints can change how you feel about yourself. Collagen supports all three.
02
I was tired of collagen that was under dosed

Most brands contain 5,000mg of collagen or less. Correxiko provides a clinical dose of 10,000mg.
03
Marine over Bovine: what they don’t tell you that a doctor will

Marine collagen sourced from wild-caught fish skin gives you a higher-purity, more sustainable collagen that is easier to absorb than bovine.
04
Most collagen isn’t designed for your body to absorb easily

The purpose is simple: prepare it for digestion and absorption, so your body can use what you take.
05
Your collagen shouldn’t taste like a chocolate milkshake

You’re taking it for the collagen. Ours is genuinely unflavoured, mixes smoothly, and adds no sugar, sweeteners or flavourings.
06
I made the collagen I’d give my own wife, daughters and patients

Women deserve the same care I’d want for my family: an effective dose and a considered formula, guided by medical knowledge.

1 Why collagen at all

It supports the places where ageing shows first

You notice it in the mirror, in your hairbrush, and sometimes when you get up from the sofa.

You may notice several changes together:

Skin that looks duller or feels less firm
Hair that looks finer
Joints that feel less comfortable

It can feel as though your body has changed faster than your routine can keep up with.

Collagen acts like structural “glue”, supporting your skin and the cartilage, tendons and ligaments involved in movement.

Your body produces less as you age. Hormonal changes around menopause can accelerate collagen loss in the skin by up to 30%.

Taking the right collagen supplement provides peptides your body can use to replenish what is lost. Research has explored their ability to:

Support skin hydration and elasticity
Reduce hair breakage
Improve joint pain over time

“I was hoping taking this collagen supplement would improve my lines on my face and it did. My lines are more finer and people have commented on how my skin is glowing.”

Jane Blowman, 4790-day powder trial, 2024

2 How much

I was tired of collagen that was under dosed

A cheaper pouch can become poor value if you need several servings to get the amount you intended to take.

Two “daily collagen supplements” can provide very different amounts:

2,000mg: One-fifth of Correxiko’s daily dose
5,000mg: Two servings to match Correxiko
10,000mg: One daily serving of Correxiko

Using less collagen can reduce production costs and make the price look more attractive. But taking extra servings means finishing the pouch sooner.

An 8g daily dose has been used in clinical research.

My approach was a substantial, clearly stated dose in one serving:

10,000mg of marine collagen peptides
100 daily servings in every 1kg tub
One ingredient, with no sugar, sweeteners, flavours or fillers

You know what you’re taking, without doubling up on scoops or finishing your tub sooner than expected.

10,000 mg Daily DoseAn easy-to-mix 10 g dose for visible results.
Clean FormulationNo fillers, binders, additives or preservatives.
Collagen TypesTypes 1-4 support collagen-rich tissues throughout the body.
0% Zero fats, sugars or carbsJust 9.5g of protein
Double hydrolysedFor an industry-leading particle size for easy absorption
No sugars, sweeteners or natural flavours*

* flavours can be packed with chemicals as still be called ‘natural’

3 Where it comes from

Marine over Bovine: what they don’t tell you that a doctor will

I chose collagen-rich fish skin, then paid just as much attention to what happened to it next.

Bovine collagen comes from cattle and goes through heavy chemical processing.

For Correxiko, I chose the skin of wild-caught:

Cod
Haddock
Pollock

Fish skin is naturally rich in collagen. Using it also puts a part of the fish to use that might otherwise go to waste.

I intentionally chose this source to give you:

Higher-purity collagen
A more sustainable source
Easier absorption than bovine

Correxiko marine collagen

Skin of wild-caught cod, haddock and pollock
Higher-purity collagen
A more sustainable source
Easier absorption than bovine

Typical bovine collagen

Comes from cattle
Heavy chemical processing

4 Absorption

Most collagen isn’t designed for your body to absorb easily

The collagen in your scoop needs to become something your body can absorb.

Hydrolysis breaks large collagen proteins into smaller pieces called peptides.

Correxiko goes through two stages of hydrolysis to create fine peptides that your body can actually absorb, giving you better results.

That processing also helps the powder mix easily into everyday drinks, without a gritty, clumpy addition to your morning.

What hydrolysis does

Whole collagen. One long triple helix of about 300,000 daltons. Far too big to pass through the gut wall.

From pouch to body

1
Marine collagen
2
Two stages of hydrolysis
3
Small peptides
4
Digested and absorbed
5
Available for your body to use

5 What’s left out

Your collagen shouldn’t taste like a chocolate milkshake

You’re buying collagen to support yourself. You shouldn’t have to take unwanted extras with it.

A chocolate-flavoured collagen might sound appealing. But check what creates that taste, and how much of each serving is actually collagen.

Plenty of brands add:

Added sugar
Sweeteners
Flavourings
Colours
Preservatives

These don’t increase the amount of collagen you’re getting. If you’re reducing added sugar or keeping your supplements simple, they may be extras you’d rather avoid.

Correxiko contains one ingredient: double-hydrolysed marine collagen peptides.

It’s genuinely unflavoured and mixes smoothly, so:

Your coffee still tastes like coffee
Your smoothie keeps the flavour you chose
There’s no sweetened chocolate or berry taste to work around

Your daily collagen, without added sugar, changing your breakfast or creating another routine.

No sugar, sweeteners or flavours. Just double-hydrolysed marine collagen, so it disappears into your coffee instead of tasting like dessert.

6 Why I made it

I made the collagen I’d give my own wife, daughters and patients

The care I’d want for the women closest to me is the care I wanted to put into this product.

I’m a former NHS gut doctor and the founder of Correxiko. My interest in collagen developed while using it to support patients recovering from surgery.

I became frustrated by the supplements people were buying:

Unclear doses
Unnecessary ingredients
Confident promises that were difficult to judge from the formula

That frustration became personal when I saw my wife buying products for her hair, skin and joints, and finding the formulation didn’t live up to the marketing.

She deserved better. So did my patients.

That led to Correxiko: 10,000mg of double-hydrolysed marine collagen peptides per daily serving, with nothing else added.

Don't take my word for it

We tested Correxiko Marine Collagen for 90 days with women aged 35 to 65.

88%: saw better skin health and appearance
76%: noticed improvements in their hair and nails
96%: would recommend Correxiko to family and friends

Before and after

Photos from Correxiko customers.

Drag across each photo to compare

“Since using Correxiko powder, my hair is thicker and shinier, my nails are stronger and my skin feels softer, more hydrated, and the lines have diminished.”

Andrea Lloyd, 6490-day powder trial, 2024

What sticking with it can look like

First month

The routine settles in. Some people notice softer, more hydrated skin or better nails.

Taking it every day matters more than getting it perfect.

My recommended daily foundation

Marine Collagen Powder, 1kg tub

Rated 4.8 out of 5 by thousands of customers

Correxiko Marine Collagen Powder, 1kg tub

10,000mg hydrolysed marine collagen peptides a day · 100 servings · Unflavoured and heat-stable · No sugar, sweeteners or additives

Save 11% Subscribe & Save£0.79 a serving · a new tub every 90 days £79.21 One-time purchase One tub, no subscription £89.00

90-day money-back guarantee
Pause, skip or cancel any time

In their own words

Correxiko customers, filmed on their own phones.

Caroline Cook, 62

Claire G.

Fiona L.

Helen McBride-Clavis, 45

Julie K.

Michelle B.

“I have to admit that before commencing the trial I did not think I would notice any difference. I was wrong. The main benefit was regarding my nails. They were thin and weak prior to the trial but are now strong and long.”

Caroline Cook, 6290-day powder trial, 2024

“I have been trying this product for the past 3 months and definitely noticed a change in my skin. It appears to be smoother especially on my forehead and feels softer and less wrinkly.”

Helen Capstick, 5390-day powder trial, 2024

“It’s definitely made a difference to my skin which looks more plumped up. My hair is growing much faster too.”

Ruth Langley, 6090-day powder trial, 2024

How Correxiko compares

How Correxiko compares
	Correxiko	Typical collagen
Daily dose	10,000mg	Often 2,000 to 5,000mg
Doctor-formulated	Yes	No
Source	Wild-caught marine	Bovine, with small traces of marine, branded as “Multi-Collagen”
Hydrolysed peptides	Yes	Varies
Flavours and sweeteners	None	Often added
Preservatives	None	Often added
Types I, II, III and IV	Yes	Only types I and III
90-day guarantee	Yes	Varies

Questions I'm often asked

Doesn’t collagen just get broken down in the stomach?

Yes, and that’s partly the point. Hydrolysed collagen is digested into smaller peptides and amino acids that are absorbed through the small intestine. Your body then uses them as building blocks and signals in collagen-rich tissue.

I tried collagen before and saw nothing. Why would this be different?

Dose, source, formula and consistency all matter. A lot of products give you 2 to 5g a serving. Correxiko gives you 10g of hydrolysed marine collagen peptides a day with nothing added, and you have 90 days to judge it.

Do I need to take vitamin C with it?

No. Vitamin C helps your body make its own collagen, but you don’t need it to absorb collagen peptides. Take Correxiko with or without it.

When will I notice a difference?

Some people notice changes in hydration or texture within four to eight weeks. More obvious changes usually take around 90 days, and hair, nails and joints can take longer.

Is it too late to start in my 50s, 60s or later?

No. Your body keeps renewing skin and connective tissue throughout life. The aim isn’t to stop ageing. It’s to give the parts that change with age the nutrition they need.

Will it taste fishy?

It’s unflavoured and made to mix into drinks and food. Because we don’t hide it behind flavours or sweeteners, you might notice a very mild natural taste, depending on what you mix it with.

Am I locked into the subscription?

No. You can pause, skip or cancel when you need to.

Dr Dinuk at a patient's bedside in hospital — Dr Dinuk on the ward

A note from Dr Dinuk

You don't need another product with big promises

You need clean collagen, at a dose that matters, taken for long enough to judge it fairly. That's what I made Correxiko to do.

Take 10g every day for 90 days. Then decide based on what you see and feel, rather than anything I've told you.

Dr Dinuk Dissanayake

Learn more about Correxiko

10,000mg marine collagen · 100 servings per tub · 90-day guarantee