How Nitrate Consumption Affects Health

Nitrate is a compound that occurs naturally in the body and is also present in foods such as green leafy vegetables. A diet rich in nitrates can improve oral and cardiovascular health. Moreover, nitrates have been shown to improve endurance during high-performance exercise (1).

 

Despite their benefits, some foods containing nitrate can be carcinogenic to humans (2).  So, which nitrate-containing foods are good for health and why? In this article, we will discuss all that you need to know about nitrate and its effects.

 

High Nitrate Foods

Nitrates are present in vegetables, such as spinach, lettuce, rocket, kale, carrots, and beetroot. Additionally, inorganic nitrates are also used to preserve processed meats, such as bacon and sausages. However, when ingested, nitrates present in processed meats can interact with proteins in the food and form nitrosamines, which are carcinogenic and increase bowel cancer risk (2).

 

In contrast, nitrates derived from vegetables are converted into nitric oxide (NO) by microorganisms in the mouth (3). Nitric oxide is associated with positive oral and cardiovascular health and can also improve sports endurance.  Fortunately, only 5% of our diet consists of nitrates derived from processed meat, whilst approximately 80% of nitrates in our diet come from vegetables. 

 

 

                     

 

                           Green leafy vegetables are high in nitrates

 

 

 

 

 

The Effects of Nitrate on Health

 

Nitrate and Oral Health

Regularly consuming green leafy veggies will cause a positive shift in the oral microbiome by increasing the presence of nitrate-reducing bacteria (that facilitate nitric oxide production) associated with good oral health (Rothia and Neisseria species) and reducing bacterial species associated with gingivitis (Streptococcus, Veillonella and Prevotella species). Thus, a diet rich in nitrates can help prevent a chronic oral infection known as periodontal disease, which affects 20-50% of the global population (4).

 

Symptoms of periodontitis include bad breath, bleeding gums, and tooth loss. Additionally, using nitrate supplementation as a treatment method for periodontitis could help to alleviate symptoms whilst reducing the occurrence of antimicrobial resistance— as mouthwashes typically used to treat this disease can induce bacterial tolerance to antiseptics (5, 6).   

 

 

Nitrate on Cardiovascular Health

Nitrate-reducing bacteria in the oral cavity are also linked to improving cardiovascular health (7). Nitric oxide is a signaling molecule that can mitigate cardiovascular events by inducing relaxation within arterial walls, thus causing blood vessel dilation and reduced blood pressure. Nitric oxide can prevent hypertension (high blood pressure) and reduce the occurrence of endothelial thickening associated with atherosclerosis. 

 

Hypertension is a leading cause of premature death in the UK, thus significantly increasing the risk of heart attack and stroke (8). Studies have found a single serving of green leafy vegetables per day can substantially lower’s your risk of cardiovascular disease risk by approximately 11%. 

 

Nitrate and Exercise Performance

Nitrate consumption can also enhance exercise performance. Nitric oxide reduces fatigue and increases nutrient and oxygen delivery to working muscles, thus improving exercise tolerance and boosting post-exercise recovery. It also improves energy production within mitochondria (powerhouses within cells) and enhances the excretion of metabolic by-products produced by high-intensity exercise. A study analysed the effects of drinking beetroot juice before engaging in high-energy sports and found participants had a lower oxygen intake and greater exercise tolerance than a placebo (9).

 

 

                       

 

                        Beetroot juice can improve exercise performance.

 

Interactions between Nitrate and Health 

The health benefits associated with nitrate consumption are interrelated. A daily serving of green leafy vegetables increases the activity of nitrate-reducing bacteria in the mouth to reduce periodontal disease risk or alleviate gingival symptoms. Nitrate reduction leads to high levels of circulating nitric oxide in the body which impacts cardiovascular health by reducing blood pressure and promoting a healthy endothelium within blood vessels.

 

 Moreover, nitric oxide can also enhance exercise performance by improving oxygen and nutrient delivery to working muscles and increasing the excretion of metabolic by-products produced by high- intensity sports.

 

Bottom line

Overall, processed meats should be consumed sparingly, and green leafy vegetables should form part of an individual's daily diet to promote good health. An individual's nitrate needs can be met by consuming 250-500g of green leafy vegetables daily.

 

By: Siobhan Moran, BSc (Hons), MSc