Cut From Steel

The one-eyed surgeon who studied what we flush.

Denis Burkitt lost his right eye in an accident in 1922, when he was a boy. He became a surgeon anyway. In 1948 he went to work at Mulago Hospital in Kampala, Uganda.

Burkitt made his name there in 1958 by describing a childhood cancer. He found it in children he treated in Uganda. Doctors still call it Burkitt lymphoma. Plenty of men would have coasted on that for the rest of their careers.

Burkitt did not coast. In his sixties he turned to a far less glamorous subject… what people ate and what came out the other end. He became convinced that low-fibre Western diets were behind diseases he rarely saw in rural Africa.

Burkitt spent the 1970s writing and lecturing about fibre to anyone who would listen. He co-wrote Don't Forget Fibre in Your Diet in 1979. His most famous line about it opens today's letter. Some of his ideas have been refined since, but he got the world talking about the subject it avoids.

You can laugh at a surgeon who talked about stools for a living. Burkitt started a second career in his sixties by asking an embarrassing question. He was right that nobody wants to talk about it. Today's letter asks it again.

The morning you dread

You sit on the toilet longer than you used to. Some mornings nothing happens at all, so you try again after coffee. You may feel bloated and heavy for the rest of the day. Most men never mention it to anyone.

I have heard the same advice you have. Eat more fibre, drink more water, and stop complaining. Doctors have handed it out for decades. That advice sounds right, but a large review says it is too vague to help most people with constipation.

You deserve better than a vague lecture. The British Dietetic Association published evidence-based dietary guidelines for chronic constipation in October 2025. Their findings are specific enough to try at breakfast. Most of them are cheap, and most are already in your supermarket.

What actually worked

King's College London researcher Eirini Dimidi led the work. Her team reviewed more than 75 clinical trials. Dimidi has said there simply isn't enough evidence that a general high-fibre diet works for constipation specifically. In other words, the most common advice was the weakest. Three specific fixes did much better.

01 / Two or three kiwis

You can eat two or three kiwifruit a day, with or without the skin. The review found kiwis came out on top for helping people go more often. Prunes helped too, though they caused more side effects.

02 / Psyllium

You can buy psyllium husk at any pharmacy. Doses above 10 grams a day showed consistent benefits, especially after at least four weeks. Build up slowly, because jumping straight in can cause bloating. Ask your pharmacist if you take other medicines, because psyllium can affect how some are absorbed.

03 / Mineral water and rye

You can swap some tap water for a high-mineral water. The guidelines also back rye bread, magnesium oxide supplements, and certain probiotic strains. Senna, a common laxative, had weaker evidence than you might expect. Each of the winners had more trial support than the generic advice.

A four-week trial

You can run your own trial starting tomorrow. Eat two kiwis every morning for four weeks. Keep a note of how often you go and how hard it is. If you go more easily, you have your answer.

You can add psyllium if the kiwis are not enough. Start with a small dose and raise it over a couple of weeks, with plenty of water. Psyllium soaks up water, so drinking enough matters.

You should make the changes one at a time so you know which one helps. Change everything at once and you will never know what worked.

I would see a doctor rather than self-treat if anything changes suddenly. Blood in your stool, weight loss you cannot explain, or a change in habit that lasts should all be checked. Those can be signs of something more serious, including colon cancer.

One last thing. Burkitt spent his sixties talking about the subject everyone avoids. Two kiwis and an honest note will tell you more than another lecture.

— Travis

Can’t poop? 🚫 DO NOT eat this fruit

Health experts say that fiber from fruit can relieve constipation.

BUT — recent studies show that this ONE common fruit disrupts your digestive system…

Makes passing stool HARDER…

And could even destroy your intestines.

But before I tell you about it…

Do you know which fruit it is?

Click on the image above with the right answer…

Or go HERE to discover the #1 fruit you need to avoid if you’re constipated.

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