Cleaner Air for Lower Cardiometabolic Risk

Inclusion Criteria: Participant is ≥18 years old Participant and members of household are reported to be non-smokers (defined as no household members are currently known to smoke cigarettes or use other tobacco products including e-cigarettes) Participant is to understand/speak English or Spanish Participant can understand study procedures and give informed consent Participant has prediabetes, defined as the absence of diabetes and any of the following: fasting plasma glucose 100-125 mg/dL, 2 hour plasma glucose of 140-199 mg/dL after 75 g oral glucose tolerance test, or A1c 5.7- 6.4%. Able to wear CGM for 2 two-week periods Able to participate in telephone or video conference for home equipment setup if needed Able to visit clinic for blood draws before and after the study period Do not intend to sleep anywhere outside of primary bedroom for more than 48 consecutive hours or a total of 7 days during the study period. Ability to lift, or access to assistance with lifting, 20 lb to set up air filter appliance in bedroom. Have not undergone major dietary change (such as change from usual diet to intermittent fasting or caloric restriction) in the past 2 weeks, and do not intend to during the study period Exclusion Criteria: Participants who have diagnosed diabetes, or take antihyperglycemic medications Participants with known atherosclerotic disease: coronary artery disease, peripheral artery disease or history of cerebrovascular disease (stroke or Transient Ischemic Attack (TIA), carotid stenosis) Participants with known systemic inflammatory conditions (including but not limited to: inflammatory arthritis, vasculitides, inflammatory bowel diseases, cancer within past 5 years, Hashimoto's thyroiditis) Participants currently taking any anti-inflammatory medications or medications that target inflammatory cytokines Pregnancy: because blood glucose problems during pregnancy require intensive monitoring and lifestyle changes to protect the mother and fetus Participants with known or suspected Covid-19 in the prior 30 days Participants with post-covid sequelae (a.k.a "Long covid") Participants who are already utilizing HEPA filtration (PAC or within HVAC) in bedrooms