Abstract Body: Excessive sodium (Na) and inadequate potassium (K) intake are recognized as important risk factors for hypertension (HTN). Salt substitutes (SS) offer a potential strategy to reduce Na intake, yet trends in SS use in the U.S. population have not been explored. This study examined SS use among U.S. adults and HTN subgroups from 2003 to 2020 using data from the National Health and Nutrition Examination Survey (NHANES).
Adults aged ≥18 years were categorized into 4 subgroups based on presence of HTN (BP ≥130/80 mmHg) and antihypertensive medication use: 1) treated/controlled HTN, 2) treated/uncontrolled HTN, 3) untreated HTN, and 4) normotensive. Salt types were classified as ordinary salt (e.g., iodized salt, sea salt, etc.), SS (e.g., K-enriched or other SS), and no salt use. Additional analysis was performed in SS-eligible subjects with estimated glomerular filtration rate ≥ 60 ml/min/1.73m² and not taking concomitant medications that reduce K excretion or K supplement. We also evaluated frequency of eating out to assess its influence on SS use. All analyses incorporated NHANES sampling weights and complex survey design.
SS use among all U.S. adults remained low, peaking at 5.4% in 2013–2014 and falling to 2.5% by 2017–March 2020. Among eligible adults, use ranged from 2.3% to 5.1%. Usage was highest in individuals with treated and controlled hypertension (3.6–10.5%), followed by those with treated but uncontrolled hypertension (3.7–7.4%), while use remained consistently <5.6% among untreated and normotensive individuals (Figure 1A). Adults eating out ≥3 times/week had 23% lower odds of using SS compared to those who ate out less frequently (OR: 0.77, 95% CI: 0.64–0.92, p=0.0055; Figure 1B).
In a nationally representative sample of U.S. adults, SS use remained uncommon over two decades, including among those with HTN. Even among individuals with treated/ uncontrolled or untreated HTN, fewer than 8% reported using SS, while the majority continued to use ordinary salt. Low SS use may be related to higher frequency of eating out where individuals have limited control over the salt type. Greater efforts are needed to promote SS as part of dietary strategies to support HTN control, particularly among individuals with persistent or poorly controlled HTN.