Most people know that it is important to include vegetables in our diet due to the health benefits of high fiber, vitamins, minerals, and antioxidants.
But did you know that many vegetables, particularly red beetroots and leafy greens, are very high in dietary nitrates? What is so important about dietary nitrates?
These dietary nitrates play a cardio-protective role by lowering blood pressure, reducing the inflammation response, and improving endothelial function. The body metabolizes dietary nitrates (NO3-) by first converting it to the biologically active form (NO 2 ), and then to Nitric oxide (NO).
Nitric oxide is a vasodilator and is responsible for regulating blood flow, muscle contractions, glucose and calcium homeostasis, as well as cellular respiration in the mitochondria. Previously it was though that dietary nitrates could not influence nitric oxide production, however new research challenges that and suggests that beetroot juice has a direct relationship on lowering systolic blood pressure.
Beets are also rich in betaine, which gives it that vibrant red color and has been used in cardiovascular treatments. These high antioxidants also aid in protecting against oxidative stress in the body.
Dietary nitrate supplementation has been shown to increase athletic performance by improving oxygen efficiency, reducing the amount of Oxygen needed to perform the same amount of work. Low levels of nitric oxide has been associated with hypertension and even elevated cholesterol.
Some factors that can alter the nitrate content in vegetables include environmental factors such as humidity, amount of sunlight, and water, pesticides and the genetics of the plant.
Consumers should be cautious however, about proper storage of high nitrate containing vegetable juices. Improper storage can accumulate large amounts of bacteria that accumulate nitrite buildup, which can become harmful. High amounts of nitrite have toxic and even deadly effects, which are seen in nitrate and nitrite containing drug use, such as nitroglycerine, and amyl nitrite.
Nitrites can also form N-nitrosamines in the body, which has been found to be carcinogenic in animals, but still has yet to proven in humans. While it is still unclear what the optimal level of daily dietary nitrate consumption is, the Dietary Approaches to Stop Hypertension (DASH) diet yields 20mmol of nitrate per day.
Current research studies are showing effective improvement of athletic ability, and decreased blood pressure with just 9 mmol (0.5 L beetroot juice or 300-500mg) nitrates daily.
Including vegetables in your diet that are highest in nitrates (>250mg/100g fresh weight) such as celery, cress, chervil, lettuce, red beetroot, spinach, and arugula can improve your overall cardiovascular health. This amount can easily be achieved with 1 cup of raw spinach containing 900mg nitrate, and a half a cup of cooked collard greens containing 200mg.
Recommendations on the amount of vegetables that are optimal for your health can be found in the Dietary Guidelines for Americans and the USDA’s MyPlate website.
1. Coleman, E, MA, MPH, RD, CSSD. Beetroot Juice and Dietary Nitrates. The Integrative RDN. Spring
2. USDA Choose Myplate website. http://www.choosemyplate.gov/. Published 2016. Accessed August 7,