In Iran, unhealthy-lifestyle risk is rising and unevenly spread

Two studies published in August 2026 describe Iran's noncommunicable-disease problem from opposite ends: the behaviours that feed it are becoming more common among people who already have diabetes, and the deaths they contribute to are distributed unevenly across the country [s1][s2].

Risk behaviours are climbing among people with diabetes

The first study drew on four rounds of Iran's STEPwise approach to noncommunicable-disease risk-factor surveillance — the nationally representative STEPS surveys of 2007, 2011, 2016 and 2021 — restricted to adults aged 25 and older who had diabetes [s1]. It scored each participant from zero to four on a set of unhealthy lifestyle behaviours: current smoking, insufficient physical activity, inadequate fruit and vegetable intake, and obesity [s1].

Across 7,674 adults with diabetes, the share carrying at least two of these behaviours rose from 55.57% in 2007 to 65.39% in 2021, an annual percent change of 1.17% [s1]. The share carrying at least three rose faster, from 13.02% to 19.29%, an annual percent change of 2.86% [s1].

The individual behaviours moved in different directions. Smoking prevalence fell, from 18.6% to 10.5%, while insufficient physical activity climbed from 59.6% to 70.4% [s1]. Obesity and inadequate fruit and vegetable intake remained highly prevalent throughout the period [s1]. The behaviours were consistently more common among women than men and remained common even among people receiving diabetes treatment [s1].

The study calculated age-standardised prevalence estimates overall and broken down by sex, residence and diabetes-treatment status, which is what lets it compare across four survey rounds spread over 14 years without the results being distorted by the ageing of the population [s1].

The pattern matters because these behaviours compound the risk faced by people who are already managing a chronic condition. A decline in smoking is real progress; a rise in physical inactivity, in the same population, works against it. The divergence is notable in its own right: a country can succeed on one modifiable risk factor — tobacco — while losing ground on another, physical activity, within the same high-risk group and the same period [s1].

The mortality burden is spread unevenly

The second study, in the Eastern Mediterranean Health Journal, examined all deaths attributed to noncommunicable disease between 2016 and 2018 — 1,105,000 deaths — across 429 districts in 31 provinces, alongside household income and expenditure data [s2].

Average noncommunicable-disease mortality ranged from 36.02 per 100,000 population in Kohgiluyeh and Boyer-Ahmad to 73.06 per 100,000 in Golestan — roughly a twofold gap between the lowest and highest provinces [s2]. Using an index of disparity, the study found inequality above 40% in Chaharmahal and Bakhtiari, Sistan and Baluchestan, and Kohgiluyeh and Boyer-Ahmad, and below 20% in Semnan and Qazvin [s2].

To quantify the inequality, the study used an index of disparity to measure variation across areas and a regression-based relative index of inequality to measure the socioeconomic gradient [s2]. Cardiovascular disease drove the steepest gradient: mortality fell from 144.1 to 118.5 per 100,000 population between the first and second socioeconomic groups [s2]. That cardiovascular disease shows the sharpest difference between adjacent socioeconomic groups is consistent with a burden that concentrates where prevention, early detection and treatment are least available [s2].

What the two studies do and do not show

Neither study establishes cause. The STEPS analysis documents trends in self-reported behaviours among people with diabetes, not the outcomes those behaviours produce [s1]. The mortality study documents where deaths are concentrated and how that tracks with socioeconomic position, but a cross-sectional inequality measure cannot say why a given province fares worse [s2]. Death-registration completeness can also vary between provinces, which affects any comparison built on recorded deaths.

The two datasets also cover overlapping but not identical periods — the behaviour trends run to 2021, the mortality analysis covers 2016 to 2018 — so they describe the same system at slightly different moments rather than a single cause-and-effect chain [s1][s2]. Read together, they nonetheless point in a consistent direction: the behavioural drivers of noncommunicable disease are becoming more common in a high-risk group, and the resulting mortality is not evenly shared. The mortality study concludes that reducing those inequalities, particularly for cardiovascular disease, should inform health-equity policy [s2]. Together the two lines of evidence make the case for interventions aimed not just at behaviours in general, but at the specific groups and provinces where risk and mortality are highest [s1][s2].

Sources

• [s1] "Temporal trends in unhealthy lifestyle behaviors among adults with diabetes in Iran: STEPS surveys, 2007-2021," Journal of Diabetes & Metabolic Disorders, 25 August 2026. https://doi.org/10.1007/s40200-026-02053-9
• [s2] "Socioeconomic inequalities in noncommunicable disease mortality in Islamic Republic of Iran," Eastern Mediterranean Health Journal, 2 August 2026. https://doi.org/10.26719/2026.32.7.437