Drinking beetroot juice that doesn't have nitrate in it every day for 12 weeks doesn't change the levels of nitrate or nitrite in your blood — so if you do see changes with regular beetroot juice, it's because of the nitrate, not the beetroot itself.

A randomized, double-blind, placebo-controlled trial in healthy middle-to-older adults (n≥50) comparing daily consumption of nitrate-free beetroot juice versus placebo juice for 12 weeks, measuring fasting and acute (post-consumption) plasma nitrate and nitrite levels at baseline, week 6, and week 12.

A within-subject crossover trial in healthy middle-to-older adults where each participant receives both nitrate-free beetroot juice and placebo juice in random order, separated by a 4-week washout period, with plasma nitrate/nitrite measured at fasting and acute timepoints after each 12-week intervention phase.

A parallel-group trial comparing nitrate-free beetroot juice, regular (nitrate-containing) beetroot juice, and placebo in healthy middle-to-older adults over 12 weeks, measuring fasting and acute plasma nitrate/nitrite to isolate the effect of nitrate removal.

A longitudinal observational study tracking plasma nitrate/nitrite levels in healthy middle-to-older adults who self-select into consuming nitrate-free beetroot juice daily for 12 weeks, compared to non-consumers.

A mechanistic sub-study using stable isotope-labeled nitrate-free beetroot juice to confirm no systemic conversion to nitrate/nitrite in plasma over 12 weeks in healthy middle-to-older adults.