If you drink a small glass of beetroot juice every day for three months, your body’s nitrate and nitrite levels go up a lot—this means your body might be making more of a helpful molecule that supports blood flow.

A double-blind, placebo-controlled RCT with 40–60 healthy adults aged 49–63, randomly assigned to consume either 70 mL of beetroot juice (380 mg nitrate) or a nitrate-matched placebo daily for 12 weeks, with fasting plasma nitrate and nitrite levels measured at baseline, week 6, and week 12.

A crossover RCT where each participant receives both 70 mL of beetroot juice (380 mg nitrate) and a placebo for 12 weeks each, in random order, with a 4-week washout period, measuring fasting plasma nitrate and nitrite levels at baseline and end of each phase.

A prospective cohort study tracking 80–100 healthy adults aged 49–63 over 12 weeks, with strict dietary control ensuring only the intervention group consumes 70 mL of beetroot juice daily (380 mg nitrate), while controls maintain their usual diet, and plasma nitrate/nitrite levels are measured at baseline and week 12.

A single-arm study where 30–50 healthy adults aged 49–63 consume 70 mL of beetroot juice (380 mg nitrate) daily for 12 weeks, with fasting plasma nitrate and nitrite levels measured at baseline and week 12 to assess change from baseline.

A small observational case series of 10–15 healthy adults aged 49–63 consuming 70 mL of beetroot juice daily for 12 weeks, with plasma nitrate and nitrite levels measured at baseline and end to describe trends, without randomization or control.