Beetroot / nitrate

What is beetroot / nitrate?

Beetroot is a root vegetable, and what a supplement made from it is really selling is the inorganic nitrate it carries, the compound that also makes green leafy vegetables interesting to researchers. It is sold as a concentrated juice shot, as powder for mixing, and as capsules and extracts, and how much nitrate a serving holds varies widely between them. It also carries the betalain pigments that give beetroot its colour, described in reviews as active against oxidation and inflammation in laboratory work. Its following began with cyclists and runners and has spread well beyond them.

Why do people take beetroot / nitrate?

What does beetroot / nitrate do in the body?

Beetroot itself does very little. What it carries is inorganic nitrate, and the interesting part starts after it is swallowed: much of the nitrate is absorbed, circulated, and then concentrated back into saliva, where bacteria living in the mouth turn it into nitrite. Nitrite carried in the blood can be converted again, this time into nitric oxide, the gas that signals the muscle in artery walls to relax.

That last step is favoured where oxygen is scarce, which is what makes the route interesting for exercise: hard-working muscle is exactly where oxygen runs low. Reviews describe nitric oxide as involved in the tone of blood vessels, in how mitochondria use oxygen and in muscle contraction itself, which is why trials measure blood pressure and oxygen cost side by side. Muscle itself holds far more nitrate than blood does, and those stores rise and fall with what is eaten.

What do people say about taking beetroot / nitrate?

These are anecdotes people have shared, not evidence.

What forms of beetroot / nitrate are there?

What else is worth knowing about beetroot / nitrate?

• Trials give doses in millimoles of nitrate, most often six to thirteen a day, roughly 400 to 800 milligrams, taken two to three hours before exercise or daily for three days or more. Labels state the amount per serving, which may be more than one capsule or scoop.
• The nitrate figure is the one to compare. Many labels give only the weight of beetroot powder or extract, which says nothing about the nitrate inside, and juice shots sold by the millilitre often state no per-serving figure at all.
• The first step happens in the mouth rather than the gut: reviews describe bacteria living there turning nitrate into nitrite before the body can use it. A review of nine trials in 284 people found nitrate shifted which bacteria were present and raised the pH of saliva.
• Most exercise trials ran days rather than months, in young and mostly male participants; the blood pressure and vessel work reaches middle-aged and older adults. A four-week trial in adults with high blood pressure reported it was well tolerated.

If you take medication, are pregnant, or have a health condition, check with a pharmacist or GP first.