Nitrates are carriers of nitrogen (N) in nature, so they are often referred to negatively in public, which is not true. Some vegetables such as radishes, turnips, celery, spinach, arugula and watercress have high natural nitrate levels, but these vary widely. Nitrates are also commonly used as an antibacterial and stabilizing agent in meat products, fish and cheese. In fact, nitrate is a normal part of our daily diet.

Decades ago, the World Health Organization (WHO) issued strict guidelines to control the upper limit of nitrate levels in food due to the potentially harmful effects of dietary nitrates on health. However, a number of potentially beneficial effects of nitrates on human health have recently been identified. Thus, the results of recent research indicate that dietary nitrates may have a beneficial effect on certain cardiovascular diseases, immunity and gut function (McKnight et al., 1999; McDonagh et al., 2018; Alsulayyim et al., 2021 ; Shannon et al., 2021).

Nitric Oxide (NO)

Nitric oxide plays an important role in the regulation of a variety of physiological processes in the heart, lungs, blood vessels, skeletal muscle and other tissues (Stamler & Meissner, 2001). The American professor Robert Furchgott discovered the role of NO in the human body. He proved that the neuronal regulation of blood vessel diameter depends on the action of NO. In 1998, Furchgott and his colleagues Louis Ignaro and Ferid Murad received the Nobel Prize in Medicine for their discoveries on the role of NO in cardiovascular regulation. Many studies have elucidated the key role of NO in modulating blood perfusion, oxygen utilization, glucose metabolism, and calcium management in skeletal muscle during contractions.

Nitrites in the blood reach their maximum value between ~2.5h and 5.5h after nitrate intake (“active window”). This time window is optimal for the absorption of nitrates, which have a positive effect on performance.

NO production in the human body

In healthy individuals, NO is readily synthesized from arginine. However, dietary nitrates provide an additional pathway for NO production. In the oral cavity, nitrate (NO3) can be converted to nitrite (NO2), which is a substrate for NO production. About 15 years ago, nitrate intake (~6 mg per kg body weight) was shown to significantly increase blood nitrite concentrations, peaking between 2.5 and 5.5 hours after ingestion (Larsen et al., 2007; Webb et al., 2008; Bailey et al., 2009). Beetroot juice concentrate is an excellent source of nitrates.

Be careful when using some mouthwashes and pastes

The use of sports supplements with nitrates does not make sense for people who use chlorhexidine (some mouthwashes, toothpastes, gels and professional coatings) because only this negatively affects the microbiota in the oral cavity. As a result, nitrates cannot be converted into nitrite.

Nitrate intake improves muscle function

Since 2007 (Larsen et al., 2007), extensive research has examined the effects of nitrate supplementation on exercise and training (Jones, 2014). Studies have shown that nitrate intake can have a beneficial effect on muscle fiber contraction through a variety of mechanisms (Jones, 2014).

During submaximal training, muscle fibers can produce a higher power output at a given oxygen consumption rate (VO2) due to the higher oxygen use efficiency of the mitochondria. At maximum exertion, improved calcium flux in fast-twitch muscle fibers can allow for greater power output. The higher availability of NO due to nitrate uptake may facilitate blood flow in active muscles. From this we can conclude that the addition of nitrates has a positive effect on performance in endurance events, short peak efforts (short sprints) and high-intensity interval training (HIIT).

Does the nitrate intake contribute to an increase in performance?

Several studies have clearly shown that taking 300-500 mg of nitrates 2-3 hours before exercise during various forms of activity can be ergogenic ( performance enhancing ) (Jones, 2014 and Sedefeld et al., 2020). The positive effects (approx. 3% on average) depend on many factors:

  • Exercise types: The positive effects are most evident in short (<30 min) high-intensity endurance exercise and in high-intensity interval training, which consists of short sprints at submaximal loads, which is characteristic of most team sports. One study found that 7-day nitrate intake (~800 mg per day) increased sprint performance at 2 x 40 minute intervals. Nitrate supplementation also improved end-of-activity reaction times (Thompson et al., 2015).
  • Training level: The more trained we are, the less impact nitrates have on performance.
  • Dosage: A single dose (~6 mg per kg = 300-500 mg; depending on body weight) 2-3 hours before training is sufficient for optimal effect.
  • Environment: Loss of performance due to hypoxia at altitude can be partially prevented by ingestion.

Are nitrate supplements safe to use?

According to the recommendations, the use of nitrates is completely safe. However, we recommend limiting the use of nitrate supplements and using them only before matches.

Recent studies suggest that increasing dietary nitrate intake may benefit certain metabolic and cardiovascular diseases (McDonagh et al., 2018; Alsulayyim et al., 2021; Shannon et al., 2021).