If older adults with high blood pressure drink beetroot juice every day for a month, their body shows more of certain chemicals in their blood and saliva that help relax blood vessels — which means their body is using a natural pathway to make nitric oxide.

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.

Drinking beetroot juice every day for a month, with about 800 mg of natural nitrates, doesn’t seem to make blood vessels in the arms work better or worse in older people who are already taking medicine for high blood pressure.

Drinking beetroot juice every day for a month is safe for people with high blood pressure—it doesn’t cause any dangerous side effects, and the only harmless things you might notice are pink urine or oddly colored poop.

Drinking beetroot juice with 380 mg of nitrate every day for 12 weeks doesn’t make your body respond any stronger to it over time—even though nitrate levels in your blood go up, your body doesn’t get better at using it or start reacting less.

Drinking beetroot juice once can temporarily make blood flow better in the arms of older people with high blood pressure, but if they drink it every day, that boost goes away after a while.