Clinical Research Directory

Inclusion Criteria: * Non-smokers (100% abstinence from use of any smoking or vaping product during the prior year) * Age ≥18 and less than 60 years old * Living in a single residence (home, apartment) located anywhere in Qatar * Mild systolic hypertension: screening visit systolic BP 130 to 159 mm Hg (off treatment or taking ≤ 2 BP medications that have been stable without changes during prior 4 weeks) plus ≥ 2 more additional criteria for the metabolic syndrome: * Waist circumference ≥102 cm if male and ≥88 cm if female * Fasting triglycerides ≥150 mg/dL (or taking a triglyceride-lowering medication) * HDL-C ≤ 40 mg/dL if male and ≤ 50 mg/dL if female (or taking an HDL-raising medication), * Fasting glucose ≥100 mg/dL Exclusion Criteria: * Pregnancy (self-reported) * Screening visit urine positive for cotinine (NicAlert \>100 ng/mL) * Living with an active smoker who smokes indoors (by self-report) * High risk conditions that prohibit allowing home BP to be \>130/80 mm Hg during the10-week trial including any cardiovascular disease (coronary artery disease, prior stroke, heart failure, peripheral arterial disease, aneurysm) or ≥ stage 3 kidney disease (estimated glomerular filtration rate \< 60 ml/min) * A medical condition placing the participant at risk from participation (per investigators) * Expected overnight travel outside their residence during the study * HEPA filter within the air conditioners of the residence (self-reported) or individual use of HEPA filter * Unable to comprehend/sign an informed consent * Lung disease requiring oxygen * Cancer receiving treatment * Screening visit: BP ≥160/100 mm Hg or fasting blood glucose ≥126 mg/dL and confirmed diabetes with follow-up HbA1c ≥6.5%. If glucose is elevated ≥126 mg/dL but HbA1c\<6.5%, they could still participate. * Medication changes in past 4 weeks. If participants are on medications for high BP or hyperlipidemia, they will need to have had stable therapy during prior 10 weeks with no planned changes during the study * Left upper arm circumference \>17 inches as this will make BP levels inaccurate with the home monitor used * Acute illness or infectious symptoms within the prior 4 weeks.