Health outcome · disease
Cataract
Also: cataracts, lens opacity, nuclear cataract
Clouding of the lens of the eye, the leading cause of blindness worldwide and treatable only by surgery. It reaches this vocabulary through the smoke of household cooking fires, which the eye meets directly and daily.
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Why it matters indoors
The lens has no blood supply and cannot repair itself, so damage to its proteins accumulates over a lifetime and shows as clouding. The mechanism proposed for smoke is oxidative: combustion products reaching the eye, directly at its surface and through the blood, overwhelm the antioxidant defences that keep the lens transparent. It is the same argument that explains why tobacco smoking is an established cause.
That makes the cooking fire a plausible exposure, and one that falls almost entirely on women. Decades of hours spent beside an unvented fire, with the face close to the pot, is an exposure of the eye as much as of the lung — and in the populations where solid fuel is universal, cataract is both common and often untreated.
The evidence is observational and the exposure is nearly always a reported fuel type rather than a measurement, so confounding by age, nutrition and sunlight is the standing difficulty.
Indoor factors with evidence
| Factor | Effect | Population | Study design | Source | Checked |
|---|---|---|---|---|---|
| Solid fuel | HR 1.11 (1.00–1.23) | women · home | prospective cohort of half a million Chinese adults: cooking fuel and its duration recorded at baseline and at resurveys, with incident eye disease ascertained through linked health records and examined for interaction with sex and smoking | F-1787 Chan et al. Long-term solid fuel use and risks of major eye diseases in … (2021) | machine |
| Solid fuel | HR 1.16 (1.05–1.28) | never-smokers · home | prospective cohort of half a million Chinese adults: cooking fuel and its duration recorded at baseline and at resurveys, with incident eye disease ascertained through linked health records and examined for interaction with sex and smoking | F-1788 Chan et al. Long-term solid fuel use and risks of major eye diseases in … (2021) | machine |
| Biomass fuel | prevalence 9.1 | rural women · home | cross-sectional study of 760 rural women in India: cooking fuel recorded by interview together with kitchen location and ventilation, and morbidity assessed by history, clinical examination and peak expiratory flow | F-1739 Indoor Air Pollution from Biomass Combustion and its Adverse… (2013) | machine |
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Cite this page
Coridum Research. Cataract. Coridum Knowledge G-0210, 16 September 2026. https://coridum.com/k/G-0210/