Pro-, pre-, and synbiotic supplements improve cardiovascular risk factors. However, the association between nonfood pro-, pre-, and synbiotics (NPPS) and long-term all-cause and cardiovascular mortality has not been studied. Thus, our objective was to determine the impact of nonfood pro-, pre-, and synbiotics on all-cause and cardiovascular mortality.

This was a retrospective, cohort study of 4837 nationally representative American participants aged 65 years or older with a median follow-up duration of 77 months.

All-cause and cardiovascular mortality were measured.

A total of 1556 participants died during the median 77-month follow-up, and 517 died from cardiovascular disease. Compared with participants without NPPS use, participants who used NPPS experienced a reduced risk of all-cause mortality by nearly 41% (hazard ratio 0.59, 95% CI 0.43 to 0.79) and cardiovascular mortality by 52% (HR 0.48, 95% CI 0.30 to 0.76). Such an effect persisted in most subgroup analyses and complete-case analyses.

In this study, we found a protective effect of NPPS against all-cause and cardiovascular mortality in Americans aged 65 years or older. Nonfood pro-, pre-, and synbiotics can be a novel, inexpensive, low-risk treatment addition for all-cause and cardiovascular mortality for older individuals.