For the first 25 years of his career, Dr David Unwin's pay depended in part on what proportion of his patients were on metformin. The British NHS treated the prescription as good practice and built a quota around it. He had been a senior partner at the same Liverpool practice since 1986. In all that time, he could not recall a single case of type two diabetes in anyone under 55. By the time he sat down with Steven Bartlett, he was seeing patients under 25 too heavy for his scales to weigh.
The full conversation, summarised by the Public Health Collaboration here, is one of the clearest accounts available of how metabolic disease actually develops, and how it gets reversed. Unwin's clinical work, including a real-world dataset of 157 patients now in drug-free type two diabetes remission, sits at the foundation of how we think about Nico.
The patient who told the doctor he was wrong
The moment Unwin describes as the start of his career's second half was a polite letter, a furious patient, and a blood test.
He had written to a woman whose prescription records suggested she had stopped taking her metformin. She came in ready to argue. Her blood glucose, she said, would be perfectly normal. She had taught herself online that bread was sugar, that breakfast cereal was sugar, that rice was sugar. She wanted to know whether Unwin was actually qualified, given that he had spent ten years not telling her this.
Her test came back normal. It was the first case of drug-free type two diabetes Unwin had seen in 25 years. She was one of 40,000 people on an online forum working it out without doctors.
He went home, told his wife Jen, a clinical health psychologist who had just picked up a low-carb book from a supermarket bargain bin, and the two of them started seeing 18 volunteer patients on Monday nights. They worked unpaid, in their own time, because the other partners at the practice thought low-carb was disreputable.
That was 2013. The results came in fast. Liver function recovering in weeks. Blood pressure dropping. Weight falling. Average blood sugar normalising. He has been publishing the data ever since.
Your whole circulation contains the equivalent of one sugar cube
Bartlett asked, on camera, how much sugar sits in the five litres of blood in a healthy adult. The answer is one teaspoon. A single four-gram cube. That is what your body works minutely to defend.
Now consider what Unwin laid out on the table during the interview. A bowl of unfrosted cornflakes contains the glycaemic equivalent of eight cubes. A medium baked potato, nine. A ripe banana, six. A milk chocolate bar, seven and a half. 150 grams of boiled white rice, ten. The highest-impact food on the table, in terms of how much glucose it will pour into your bloodstream, was the one most people grew up being told was healthy.
Bananas are not the problem. The body has to hold one teaspoon's worth of sugar in five litres of blood, and the foods we have agreed are normal can pour many times that into the system in one sitting. If your insulin is healthy, you absorb the spike and move on. If your insulin is struggling, every spike does damage you cannot feel.
The cavalry coming over the hill
Asked what gives him hope, Unwin pointed at the continuous glucose monitor on his arm. He called CGMs the cavalry coming over the hill. Once you have seen your own blood sugar respond to ketchup, to white rice, to a smoothie marketed as healthy, the marketing stops working on you. You become harder to fool.
This is the precise reason we built Nico around a CGM. Unwin's patients learn from teaspoon charts and infographics, which is excellent education. Our members learn from their own bloodstream, which is unanswerable. You cannot argue with the trace on your phone.
Behaviour change usually fails for lack of information, not lack of discipline. The CGM provides the information. Our role is to interpret what it is telling you and help you turn that into the next small change, and the one after.
Dr Unwin is one of Nico's heroes
Unwin's clinic does five things that we built Nico to do at scale. He measures, so people can see what is actually happening in their body. He teaches, so people understand carbohydrate and insulin well enough to make their own decisions. He uses CGMs, so feedback is immediate and personal. He runs GRIN, so behaviour change is specific and noticed. And he refuses to blame patients when the standard advice fails them.
Every recommendation he makes is available to our members. The CGM is the foundation. The coaching is built on the same principle Jen Unwin published: goals you can see, resources you already have, small steps, noticing. The teaspoon-of-sugar idea is roughly what your CGM does for you in real time, with your own physiology in the loop instead of an infographic on the wall.
Further reading: Public Health Collaboration, Dr David Unwin on Diary of a CEO: fatty liver. Follow Dr Unwin on X at @lowcarbGP.