The Island That Bent the Curve
Mauritius is the first country to show type 2 diabetes falling, from 23.3% in 2009 to 19.9% in 2021, measured by oral glucose tolerance test.
Mauritius is the first country to show type 2 diabetes falling, measured properly, over 34 years.
Seven surveys. The same test. Thirty-four years. Mauritius measured type 2 diabetes with the two-hour oral glucose tolerance test — the WHO's gold standard, the one that catches the people a fasting glucose misses — in 1987, 1992, 1998, 2004, 2009, 2015 and 2021. Adults aged 25 to 74. Participation above 85% every round. 36,744 survey attendances in all.
Age- and sex-standardised prevalence was 14.7% in 1987. It climbed to 23.3% in 2009. In 2021 it was 19.9%. That is a fall of 11% in men and 16% in women from the peak, 3.4 percentage points in absolute terms. The drop pointed the same way across age, across sex, and across ethnic groups. Prediabetes fell harder: 24.9% in 2009, 15.6% in 2021. And the share of cases that were newly diagnosed — people who had the disease and didn't know — dropped from 67% in 1987 to 32.5% in 2021.
The paper is in The Lancet Diabetes & Endocrinology. It was presented at the European Association for the Study of Diabetes in Milan at the end of September, and it is still moving through the briefings this week, including Nature's. Stefan Söderberg, a professor at Umeå and a co-author, points at legislation, nutrition and tobacco policy, screening programmes and mobile clinics. He also says the quiet part: Mauritius is the only country that has run this test, continuously, for this long. Everyone else is estimating.
The authors do not claim a specific policy did the work. The commentary published alongside the paper says the sharper finding is that high-quality surveillance can reveal an epidemic turning at all.
Key Facts
- Seven surveys, 1987 to 2021. 36,744 attendances. Adults 25–74. Participation above 85% each round.
- Prevalence, age- and sex-standardised: 14.7% (1987), 17.3% (1992), 20.2% (1998), 18.6% (2004), 23.3% (2009), 23.1% (2015), 19.9% (2021).
- 2009 to 2021: down 11% in men, 16% in women. Absolute drop: 3.4 percentage points.
- Intermediate hyperglycaemia: 20.8% (1987), 24.9% (2009), 15.6% (2021).
- Newly diagnosed, as a share of all cases: 67.0% (1987) to 32.5% (2021).
- Method: WHO 2006 criteria, two-hour oral glucose tolerance test.
- Co-author: Stefan Söderberg, Umeå University.
Why This Matters
Almost every country is still reporting a rise. One country, measured with the test that doesn't flatter the numbers, has a fall. That is the difference between "diabetes only travels in one direction" and "a national trend can be bent." The test is the story as much as the drop. Fasting glucose alone misses people, which means a large share of the international comparison is guesswork. Mauritius did not guess.
What We Don't Know Yet
Which policy moved the number. The study does not isolate one. The data stop in 2021 — this is not a 2026 result, it is a 2026 publication of a series that ends five years ago. And 19.9% is still one adult in five. A fall is not a cure. Do not say Mauritius solved diabetes. Do not say 3.4 percent when the figure is 3.4 percentage points.