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Nitric Oxide Complex

Also known as: Nitric oxide (NO), Inorganic nitrate (NO₃⁻), Nitric oxide complex, Inorganic nitrate supplementation, Nitric Oxide

Overview

Nitric oxide (NO) is a crucial molecule for vascular health, acting as a vasodilator. Inorganic nitrate (NO₃⁻), a precursor to NO, is found in leafy greens, beets, and certain fruits. It's used to enhance physical performance, especially in endurance and aerobic exercises, and to support cardiovascular health. In the body, inorganic nitrate converts to nitric oxide, improving blood flow and reducing blood pressure. Research on nitric oxide is extensive, with numerous studies and systematic reviews, but outcomes vary. Evidence quality is mixed, with some studies showing significant benefits and others revealing trivial effects. Overall, nitric oxide and its precursors are considered ergogenic aids with potential cardiovascular benefits.

Benefits

Nitrate supplementation can improve physical performance in healthy individuals and non-athletes, particularly in prolonged open-ended tests. However, in clinical populations with cardiopulmonary and metabolic diseases (CPMD), the benefits are less clear, with only 46% of studies reporting ergogenic benefits and an overall trivial effect on physical function. Nitric oxide can improve oxygenation in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS), although this improvement is limited and does not translate to a mortality benefit. Non-athletes may benefit more from nitrate supplementation in terms of physical performance compared to athletes. Effect sizes for physical performance improvements are generally small to moderate.

How it works

Nitrate supplementation converts to nitric oxide (NO) in the body, acting as a vasodilator to improve blood flow and reduce blood pressure. NO affects the cardiovascular system by relaxing smooth muscle cells in blood vessels, leading to vasodilation. NO activates guanylate cyclase, producing cyclic guanosine monophosphate (cGMP), which causes smooth muscle relaxation. Inorganic nitrate is absorbed efficiently from the gastrointestinal tract and converted to NO, primarily through oral bacteria and gastric acid action.

Side effects

Nitric oxide supplementation is generally considered safe when used appropriately, but potential risks and side effects exist. Common side effects are not consistently reported, but gastrointestinal symptoms can occur. Uncommon side effects include an increased risk of renal dysfunction in patients receiving inhaled nitric oxide for ALI/ARDS. Rare side effects are not significantly reported in the literature reviewed. Potential interactions exist with medications affecting blood pressure or vascular function. Use with caution in patients with severe renal impairment or those at risk of methemoglobinemia. Children with congenital heart disease may experience increased methemoglobin levels.

Dosage

The minimum effective dose is typically around 500-1000 mg of inorganic nitrate per day, though optimal dosing varies based on the specific application and population. For physical performance, doses range from 500 mg to 2000 mg per day. Dosing may need adjustment based on individual responses and health status for clinical populations. There is no established maximum safe dose, but higher doses may increase the risk of side effects such as gastrointestinal symptoms. It is best taken 2-3 hours before exercise or physical activity to allow for peak NO levels. Beetroot juice and supplements are common forms; ensure they contain sufficient inorganic nitrate. Oral bacteria and gastric acid play crucial roles in the conversion of nitrate to NO.

FAQs

How long before exercise should I take nitrate supplements?

Typically, it is recommended to take nitrate supplements 2-3 hours before exercise to allow for peak nitric oxide levels in the body.

Is nitrate supplementation safe for everyone?

Generally safe, but caution is advised in certain populations such as those with severe renal impairment or those at risk of methemoglobinemia.

How often should I take nitrate supplements?

Usually once or twice a day, depending on the specific protocol and individual needs. Follow the guidelines provided by healthcare professionals.

When can I expect to see benefits from nitrate supplementation?

Benefits can be observed within a few days to a week, depending on the individual and the specific protocol being followed.

Does nitrate supplementation improve performance in all individuals?

No, benefits are more pronounced in non-athletes and may be trivial in clinical populations with cardiopulmonary and metabolic diseases.

Research Sources

https://www.mdpi.com/2072-6643/16/22/3832 – This systematic review and meta-analysis examined the ergogenic effects of nitrate supplementation in clinical populations with cardiopulmonary and metabolic diseases (CPMD). The study found that while 46% of individual studies reported ergogenic benefits, the overall meta-analysis showed a trivial effect on physical function due to large heterogeneity and small sample sizes, highlighting the need for careful consideration of the specific population and health status.
https://pubmed.ncbi.nlm.nih.gov/17383982/ – This study investigated the effects of inhaled nitric oxide in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). The findings indicated a limited improvement in oxygenation but no mortality benefit, and potential harm such as renal dysfunction, suggesting that while nitric oxide may improve oxygenation, it does not translate to significant clinical improvements in these patients.
https://www.cochrane.org/CD005055/ANAESTH_inhaled-nitric-oxide-to-treat-high-blood-pressure-of-the-pulmonary-vessels-after-surgery-in-infants-and-children-with-congenital-heart-disease – This Cochrane review assessed the use of inhaled nitric oxide in children with congenital heart disease and pulmonary hypertension. The review found improved oxygenation but noted the evidence was of very low quality and there was a significant increase in methemoglobin levels, indicating potential risks and the need for careful monitoring in this population.
https://pubmed.ncbi.nlm.nih.gov/29553034/ – This study focused on the impact of nitrate supplementation on physical performance. The results showed that nitrate supplementation improved physical performance specifically in non-athletes during prolonged open-ended tests, suggesting that the benefits of nitrate supplementation may be more pronounced in individuals who are not already highly trained athletes.
https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2022.953912/full – This research article provides a comprehensive overview of the physiological effects of dietary nitrate supplementation. It highlights the role of nitrate in enhancing nitric oxide production, improving blood flow, and potentially boosting exercise performance, while also discussing the factors that influence its effectiveness and safety.