Gas stoves raise indoor pollution. The evidence links them to childhood asthma

Cooking on a gas stove releases nitrogen dioxide and other combustion products into indoor air, and the accumulated evidence links that exposure to a modestly higher risk of childhood asthma [s1][s2]. The relationship is an association drawn from observational studies, not a demonstrated cause-and-effect, but it is consistent across decades of research and underlies renewed attention to how homes are ventilated [s2][s3].

The clearest quantitative summary comes from a 2013 meta-analysis pooling studies of indoor NO2 and gas cooking in children [s2]. It found a summary odds ratio for asthma and gas-cooking exposure of 1.32 (95% confidence interval 1.18 to 1.48), and separately linked indoor NO2 to current wheeze with an odds ratio of 1.15 (95% CI 1.06 to 1.25) [s2]. In plain terms, children in homes that cook with gas had roughly a third higher odds of asthma than those in homes that did not, on average across the studies [s2].

The "one in eight" figure

The number that drew headlines is a population attributable fraction. A 2022 analysis applied a pooled odds ratio of 1.34 to the fact that about 35% of US households cook with gas, and estimated that 12.7% of current childhood asthma in the United States (95% CI 6.3% to 19.3%) is attributable to gas stove use [s1]. Because the calculation depends on how common gas stoves are locally, the state-level fractions varied widely: 21.1% in Illinois, 20.1% in California, 18.8% in New York and 15.4% in Massachusetts [s1].

Two cautions belong with that figure. First, a population attributable fraction is a modelled share of cases that could theoretically be prevented if the exposure were removed and the association were causal — it is not a count of children made ill, and it inherits all the uncertainty of the underlying odds ratio [s1]. Second, the input odds ratio is drawn from the same body of observational literature that cannot fully separate gas cooking from housing quality, ventilation, dampness and socioeconomic factors [s1][s2].

Ventilation and what reduces exposure

The mechanism is not disputed: gas combustion produces NO2 indoors, and concentrations spike during and after cooking, especially in small or poorly ventilated kitchens [s3]. The World Health Organization sets indoor NO2 guideline levels precisely because the pollutant irritates airways and is linked to respiratory symptoms [s3]. Using a range hood that vents outdoors, opening windows while cooking, and running exhaust ventilation are the interventions that directly lower measured NO2 during cooking, though the trial evidence that these steps translate into fewer asthma cases is thin rather than settled [s3]. Portable air cleaners with HEPA filters reduce fine particles substantially but have shown limited effect on NO2 and on asthma symptoms in controlled trials — a reminder that filtration and combustion are different problems.

What is and isn't established

What the evidence supports: gas cooking raises indoor NO2, and gas stove use is associated with higher childhood asthma risk across pooled studies [s2][s3]. What it does not establish: that a given child's asthma was caused by their stove, or that switching to electric or induction cooking would prevent a specific fraction of cases in the real world — the attributable-fraction estimates are projections, not measured outcomes [s1]. The honest summary is that the association is real and reasonably consistent, the absolute per-household risk is modest, and ventilation is the low-cost step the evidence most directly supports. This is informational reporting, not medical or home-safety advice.