What are nitrates and nitrites?
Nitrates (NO3-) and nitrites (NO2-) are substances naturally present in many fruits and vegetables or added to foods to prolong their shelf life. In this text, we will discuss the subject of nitrates naturally present in foods.
In the human body, nitrates and nitrites can be reduced to nitric oxide (NO) and used. This substance plays a role in the vasodilatation of veins and arteries, the oxygenation of tissues, the energy cycle of cells and muscle contraction. Although this component can be synthesized by the body when the oxygen level is sufficient, nitrates can be a major source of nitric oxide when the oxygen level is suboptimal for our body to synthesize. Therefore, many believe that beetroot juice can enhance sports performance when it comes to cardiovascular activities.
Why beetroot juice?
Several researchers have studied beetroot because it is the vegetable with the highest nitrite concentration. Other vegetables that are also rich in nitrates and nitrites are celery, watercress, lettuce, radish, Swiss chard, chervil and arugula.
Who can benefit from beetroot juice?
Based on the results of studies, supplementation of beet juice or nitrate-rich beet juice concentrate could be beneficial in untrained or recreational endurance athletes to improve cardiovascular performances for jogging, cycling, rowing, etc. In addition, supplementation over several days prior to exercise seems to have more benefits than a single dose. The amount typically consumed is 2 cups of beetroot juice or 70-100mL of beetroot juice concentrate per day.
However, in trained athletes, the beneficial effects of natural nitrates on physical performance in endurance sports are reduced by their adaptation to training. Often, trained athletes have a more efficient oxygen use and nitrate levels that are higher than untrained people. Therefore, beetroot juice might not be effective for well-trained athletes.
Nitrates and Cancer
Contrary to popular belief, nitrates are not cancer-causing substances. Nitrates and nitrites can often be confused with nitrosamines, which are carcinogenic substances. Nitrosamines are the result of a chemical reaction between nitrates chemically added to a food and proteins (or amino acids). This cancer-causing substance is often the result of the addition of nitrates in protein foods and food processing. The most at risk foods to avoid are highly processed meats, such as bacon, ham, sausages with added nitrates.
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