Nitrates are chemicals found in the air, soil and water. They are essential in order for plants to grow, and they are a component in most fertilizers.
Nitrates are also common food preservatives that are found in processed meats like cold cuts, hot dogs and bacon. Since nitrates (and derivatives like nitrites) are linked to serious conditions like cancer and diabetes, and acute problems like headaches, most experts recommend minimal consumption of processed products that contain these additives.
However, there is flip side to this story. Nitrate intake also happens to have some beneficial effects on the body, such as improved endurance, better endothelial function and lower blood pressure. Furthermore, nitrates can be found in many vegetables, one of the richest sources being beets.
It’s still a bit of a mystery as to why nitrates have been associated with both helpful and harmful health effects. Scientists think it may have to do with the fact that the countless protective nutrients in vegetables — antioxidants, fiber, phytochemicals, etc. — counteract the harmful effects of nitrates. Processed meats, on the other hand, have no nutritional value to offset the harmful effects of these compounds.
Whatever the case may be, researchers continue to study the positive effects of nitrates, especially when it comes to improved exercise endurance. Researchers in St. Louis wanted to examine how whole beet consumption (and the resulting increased nitrate intake) can improve endurance in runners.
Studies have already tested how sodium nitrate supplements and beetroot juice can improve exercise endurance, but this study was the first to test whole beets. Specifically, they wanted to test the hypothesis that taking 200 grams (a little less than one cup) of whole beetroot (about 500 mg of nitrates) before exercise improves running performance during a 5 km treadmill run (a little more than three miles).
You Can’t ‘Beet’ These Benefits
Five men and six women were recruited for this study. They underwent two trials. In the first, they consumed beetroot before performing the 5 km time trial; in the second, they consumed cranberry relish as a placebo. (Researchers noted that, although you can tell the difference between the two foods, the participants did not know which one was actually being studied as the performance enhancer.)
Researchers made sure the participants avoided foods that contained nitrates for 72 hours before testing. They also refrained from alcohol, dietary supplements, medications and caffeine.
Each participant ran a self-paced 5 km on a treadmill after consuming each meal. Average run times ranged from 19.9 to 35.5 minutes.
After analyzing results, researchers concluded that consuming whole beetroot did improve running performance in the study participants — on average, a 41-second faster finish time. This is especially important for athletes who would benefit from improved endurance during a competitive event. Researchers suggest consuming 200 g of beetroot, or an equivalent nitrate dose from other vegetables, about 60 minutes before exercise if you need an endurance boost.
Is a Nitrate Boost a Good Idea for You?
Given the benefits and drawbacks of nitrate/nitrite consumption, is it something everyone should be boosting?
Probably not. Most people are not endurance athletes, and therefore do not need major endurance boosts on a regular basis.
However, if you do want to boost your nitrate intake, the safest way to do so is obviously through vegetable consumption because veggies have so many other health benefits. But avoid processed meats completely, or eat them sparingly — once or twice a month at most.
Nitrate-rich vegetables other than beets include cauliflower, cabbage, radishes, celery, broccoli, spinach, lettuce, carrots, potatoes and other root vegetables.
 Murphy M et al. Whole beetroot consumption acutely improves running performance. Journal of the Academy of Nutrition and Dietetics. April 2012;112(4):548-52.