Dietary Nitrates – Key To Better Health (And Performance)
Cardiovascular disease is the number one killer worldwide.(1) Over the last half century, numerous diets have been trialled with the aim of reducing CVD risk and the common themes amongst the most successful are a high intake of fruits and vegetables.(1-7)
Naturally, it’s assumed the vitamins, minerals and antioxidants found within fruits and vegetables are largely responsible for improving blood pressure and reducing risk of CVD mortality, however it’s not so straight forward. Large-scale clinical trials have failed to fully support this idea.(8,9)
A high intake of fruits and vegetables are indeed capable of reducing the risk of a myriad of chronic diseases, yet the exact mechanism still eludes experts.
What do they know so far?
The greatest protection your diet can offer you against cardiovascular disease is the consumption of green leafy vegetables.(6)
What do green leafy vegetables provides humans beyond the vitamins, minerals and fiber?
Dietary nitrates.
How Do Dietary Nitrates Work?
When you eat certain leafy greens or beets, the inorganic nitrates abundant within them get converted in the body to nitrite. (Interestingly, approximately 20% of the nitrates re-enter the mouth via the salivary glands and are converted to nitrites by the commensal bacteria under the tongue).(10)
The nitrites are then taken up into circulation via the intestines and transported around the body to be converted into nitric oxide (NO).(11-13)
Nitric oxide (NO) is an important signaling molecule in the body, directing traffic for a number of important physiological processes;
· Blood flow regulation
· Muscle contractility
· Glucose control
· Calcium balance
· Mitochondrial health(14)
How Many Dietary Nitrates Are in Your Veggies?
The typical intake of dietary nitrates in the general population is about 31-185mg/day in European countries and 40-100mg/day in America and Canada.(15,16)
Approximately 50–85% of this dietary nitrate intake is derived from vegetables.
Spinach, arugula, beetroots, and celery contain about 250mg of dietary nitrates per 100g of fresh weight.
How many nitrates do you need to consume to achieve an effective dose?
Most studies use acute doses between 300-600mg of dietary nitrates, taken approximately 2.5 hours before exercise.
When oxygen levels are low in the bloodstream, such as during prolonged exercise, nitrites get converted into nitric oxide (NO), which is a potent vasodilator.
Dietary nitrates like beet juice effectively reduce the oxygen cost of training during submaximal exercise, potentially enhancing an athlete’s exercise tolerance.(17)
Better exercise tolerance equals better performance.
Long-term daily consumption has also been shown to increase plasma nitrite concentrations and ultimately increase the capacity of the nitrate-nitrite-NO pathway to produce nitric oxide (NO).(18)
How Long Before Dietary Nitrates Take Effect?
How long does it take the dietary nitrates from beets or leafy greens to hit maximum levels in your bloodstream? Dietary nitrates peak after 1–2 hours, and the downstream nitrites, they peak after about 2–3 hours.
Twenty-four hours later, your dietary nitrate levels will return back to baseline.
Recreational athletes seem to get the biggest bang for their buck when it comes to dietary nitrates and performance.
Why?
The margins for improvement in elite athletes are very small.
Experts believe this could be due to the greater dietary intake of highly trained athletes, or their greater capacity to produce NO, or simply because elite athletes have better genetics and thus better able to enhance oxygen delivery.(17)
Dietary Nitrates and Health Effects
Dietary nitrates are a ‘bigger win’ for recreational athletes also looking to support better health.
Cardiovascular disease is the number one cause of mortality worldwide.(1-7) Supporting better vascular health via weight management and blood sugar control is the first step, however the addition of dietary nitrates is a potent weapon due to added nitric oxide and its potent vasodilator effects.
Many cardiovascular diseases – such as pre-hypertension, hypertension, atherosclerosis and stroke – have a strong association with endothelial dysfunction (the inner lining of your smallest arteries) and reduced NO activity.(19-23)
This suggests increasing your intake of nitrate-rich vegetables would be highly beneficial.
The nitrites produced from the dietary nitrate-nitrite-nitric oxide (NO) pathway have also been found to confer specific protection from ischemia in the heart, liver, kidneys, lungs and brain.(24,25)
If you’re overweight, obese or in poor health improving blood flow is an important aspect of health.
With new regulations classifying over 50% of Americans as hypertensive, the potential benefits of dietary nitrates become ever more appealing for their ability to effectively reduce blood pressure.(26,27)
To sum up, not only do dietary nitrates support exercise performance they also support better health.
The Bottomline –
Dietary nitrates and the subsequent nitric oxide produced in the body support a number of crucial physiological processes; from blood flow regulation and muscle contractility, to glucose and calcium balance, as well as mitochondrial health.
Regardless if you’re trying to improve your endurance performance, upgrade your health or increase longevity, increasing your intake of dietary nitrates (or adding a nitrate supplement) can play a key role in achieving success.
Dr. Marc Bubbs ND, MSc, CISSN, CSCS
References –
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