Fact check: Can HMB supplements affect the efficacy of blood pressure medications in older adults?

1. Why the question matters now — supplements, older adults, and polypharmacy

Older adults commonly take multiple prescription medicines and dietary supplements, raising the general risk of drug–nutrient interactions; reviewers have flagged this as an issue for active older adults and “Masters athletes,” noting that supplement prevalence increases the potential for adverse interactions with antihypertensive therapies ^[4]. Network meta‑analyses of supplements and blood pressure underscore that some non‑HMB supplements—omega‑3s, inorganic nitrates, tart cherry juice, and vitamin D—have measurable blood‑pressure effects in older cohorts, which demonstrates a realistic mechanism by which supplements can alter cardiovascular therapy outcomes even when specific drug interactions have not been proven ^{[3] [5]}. The presence of these findings makes the absence of HMB‑specific interaction data a meaningful evidence gap ^[3].

2. What the HMB literature actually shows about cardiovascular endpoints

Clinical HMB research in older adults has focused chiefly on muscle mass preservation and sarcopenia rather than cardiovascular drug interactions. A 2018 review framed HMB as a potential therapy for elderly sarcopenia, summarizing trials of HMB for lean‑mass maintenance and functional outcomes, but it did not evaluate effects on blood‑pressure medications or pharmacodynamics relevant to antihypertensives ^[1]. A longer‑term randomized trial combining HMB with glutamine and arginine reported improvements in flow‑mediated dilation, a marker of endothelial function, which is a physiological pathway linked to vascular tone and blood pressure but is not the same as demonstrating altered responses to prescribed antihypertensive drugs ^[2].

3. What network meta‑analyses say about supplements and blood pressure—and why HMB is missing

Two network meta‑analyses published in 2024 evaluated many supplements’ impacts on blood pressure in older adults and identified several agents with consistent blood‑pressure lowering effects; both analyses cautioned about bias and potential for drug–nutrient interactions while not testing HMB interactions specifically ^{[3] [5]}. These meta‑analyses establish that some supplements exert clinically relevant hemodynamic effects, so the absence of HMB in their interaction analyses is notable: HMB was not identified as a proven modulator of systemic blood pressure in those meta‑analyses, and the studies did not examine interactions between individual supplements and cardiovascular medications ^{[3] [5]}.

4. Small vascular studies point to plausible mechanisms but stop short of clinical interaction data

A 6‑month randomized trial reported that supplementation containing HMB improved flow‑mediated dilation, suggesting endothelial benefits that could, in theory, influence blood‑pressure control or interact with drugs affecting vascular tone ^[2]. However, endothelial function changes are surrogate endpoints; they do not directly equate to altered antihypertensive drug efficacy or clinically meaningful blood‑pressure changes while on medication. The HMB literature lacks pharmacokinetic or pharmacodynamic studies showing altered drug metabolism, absorption, or receptor responses for common antihypertensives, leaving mechanistic plausibility unconfirmed by interaction trials ^[2].

5. Reviewing contrary or cautious voices — signals of risk without proof

Safety‑focused evaluations of cardiovascular supplements and combination therapies emphasize that safety and interactions are often under‑studied, particularly in older adults on established drug regimens ^{[6] [7]}. The literature on HMB and cardiac cachexia or heart failure acknowledges potential benefits for lean mass but does not document effects on blood‑pressure medications ^[8]. Multiple authors across reviews and meta‑analyses explicitly call for caution when interpreting positive supplement effects because randomization, bias risk, and lack of drug‑interaction testing limit the applicability of efficacy findings to medicated older adults ^{[5] [6]}.

6. Where the evidence gap is largest and what would resolve it

The central evidence gap is the absence of targeted pharmacologic or clinical interaction studies examining HMB co‑administered with common classes of antihypertensives (ACE inhibitors, ARBs, beta‑blockers, calcium‑channel blockers, diuretics). Existing trials address endothelial markers or sarcopenia endpoints but do not measure blood pressure while patients remain on stable antihypertensive regimens or assess drug levels, receptor occupancy, or adverse event patterns tied to combined use ^{[1] [2]}. Resolving this would require randomized crossover or pharmacokinetic/pharmacodynamic studies in older adults concurrently treated for hypertension.

7. Bottom line for clinicians, researchers, and patients — evidence, gaps, and next steps

Summing the reviewed materials: no current study provides direct evidence that HMB changes the efficacy of blood‑pressure medications in older adults, but related findings on endothelial function and the documented ability of other supplements to lower blood pressure create a credible rationale for targeted investigation ^{[2] [3]}. Multiple reviews emphasize the broader patient‑safety concern of untested supplement–drug interactions in older populations, underlining the need for clinicians and researchers to prioritize interaction studies and for clinicians to document supplement use when managing hypertension ^{[4] [5]}.