Ayurveda in Preventive and Supportive Healthcare: Current Evidence, Safety, and Clinical Integration.

Parkinson’s disease (PD) is a widespread neurodegenerative condition correlated to aging, manifested by signs and symptoms including tremors, stiffness of muscles, inflexibility, and slowed movements []. The occurrence of PD escalates by advancing age, affecting around 1% of those aged 60 and above. Increasing trends in the burden of PD from 1990 to 2019 have been observed in most regions, including Eastern Europe and high‐income North America [], which makes it one of the neurological conditions with the greatest rate of growth. Estimates for PD cases in the year 2040 vary between 12 and 17 million []. Only in the United States in 2017, PD imposed $25.4 billion of direct medical expenditures along with $26.5 billion indirect and also nonmedical charges, which made an overall economic burden of about $51.9 billion []. According to a meta‐analysis in 2024, the cost of disease for PD averages €20,911.37 per patient annually, with healthcare costs accounting for 46.1%, productivity loss for 37.4%, and costs to patients and families for 16.4% []. PD is characterized by the gradual loss of dopaminergic neurons located in the substantia nigra, accumulation of uncommon proteins such as α‐synuclein, and neuron loss in specific brain regions [], leading to motor dysfunction, cognitive impairment, and various nonmotor symptoms. While the underlying pathogenesis of PD is multifactorial, research indicates that environmental factors, particularly air pollution, may be crucial in the onset and progression of the disease [–]. According to the World Health Organization (WHO)’s definition, air pollution is known as the existence of one or more pollutants in the environment, such as gas, dust, fumes, odor, mist, smoke, or vapor, in amounts and duration that may be harmful to health, which can lead to oxidative stress, inflammation, immune system suppression, and the ability of cells to mutate [], and it can be either indoor or outdoor. Air pollution is an established risk factor for lung cancer [], chronic obstructive pulmonary disease (COPD) [], ischemic heart disease [], and stroke []. Contaminants in the atmosphere usually include particulate matter (PM), carbon monoxide (CO), nitrogen oxide (NO), ozone (O3), benzene, polycyclic aromatic hydrocarbons (notably benzo‐a‐pyrene‐BaP), sulfur oxides (SO) and various metals like manganese (Mn), arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), nickel (Ni), aluminum (Al), and vanadium (V) produced by industrial emissions, vehicular traffic, and biomass burning. WHO established air quality guideline levels in 2005, setting the permissible concentration of PM2.5 at 25 μg/m for a 24‐h exposure and a yearly average of 10 μg/m. For PM10, the daily exposure limit was set at 50 μg/m with an annual average number of 20 μg/m. However, the guidelines were revised in 2021, reducing the 24‐h exposure limit for PM2.5–15 μg/m and the average for every year to 5 μg/m, while the daily exposure limit for PM10 was adjusted to 45 μg/m with a 15 μg/m average for a year. Regarding O3, this level was set at 100 μg/m for a 24‐h exposure [, ]. By synthesizing the current evidence from epidemiological, experimental, and mechanistic studies, the intention of this narrative review is to present a comprehensive overview of the potential correlation between PD and air pollution.