If you’re a healthy plant-based eater, you probably put a lot of thought into your meals: Are you getting enough protein? Can you squeeze another serving of beans? What spices can you add to make it all more appealing? Yet when was the last time you checked in on whether you were eating nitrate-rich foods?

Probably never, but that’s no doubt about to change when you learn how crucial nitric oxide (NO) is to your overall health. “Loss of NO leads to chronic disease, and without it, you can’t be healthy or prevent the diseases of aging,” says Nathan S. Bryan, Ph.D., adjunct professor at the Baylor School of Medicine in Houston, Texas; Nitric Oxide researcher; and author of several books, including Functional Nitric Oxide Nutrition and the Nitric Oxide (NO) Solution.

While numerous lifestyle habits can impact your body’s production of NO, so, too, can eating plant foods. Here’s how to say YES to NO.

Nitric Oxide’s role in the body

Nitric Oxide is a molecule that’s naturally produced in the body. “It’s known as a signaling molecule, helping transmit signals that communicate information between different cells to trigger specific events or actions within the body,” says Catherine Kwik-Uribe, Ph.D., Global R&D Scientific & Regulatory Affairs Director with Mars Symbioscience in Germantown, Maryland.

As a result, NO plays numerous diverse roles in the body, one reason it’s been called a supermolecule. Start first with cardiovascular health. “When you walk, run, eat or just simply concentrate, blood is constantly flowing through your body and where this blood goes is in part controlled by where it’s needed,” Kwik-Uribe says. When there’s an increased demand for blood (and all that it carries like oxygen and nutrients), blood vessels sense this change and produce NO in response. “NO relaxes blood vessels to enable the smooth, easy flow of blood to the vital organs, muscles, and tissues where it’s needed most.”  This can help in everything from athletic performance and sexual function to disease prevention.

However, if your body doesn’t make enough NO, this relaxation response is impeded. As a result, more pressure is put on the cardiovascular system which can lead to blood vessels becoming stiffer and over time, blood pressure increasing, Kwik-Uribe says. Plus, NO keeps platelets from over-reacting so they don’t trigger the formation of clots unnecessarily. In other words, NO keeps your entire vascular system healthy.

NO also plays a key role in the immune system. “When there’s an infection, the body’s cells turn on their production of NO,” Kwik-Uribe. This sharp increase in NO levels is critical in mounting an effective inflammatory response and supporting immune system functioning. “The ability to turn on NO production when needed helps kill microorganisms and aids the body in fighting infection and viruses.”

So does that mean NO could potentially work to prevent and treat COVID-19? Studies are beginning to suggest this. “Early in the disease process when people are first diagnosed, I’m confident NO would have an impact on symptoms,” Bryan says. After all, high blood pressure, heart disease and diabetes put individuals at greater risk of severe outcomes of COVID-19, and NO deficiency may be at the root of those health woes.

What causes Nitric Oxide deficiency?

Several factors can decrease your body's production of NO and make you more deficient in this critical molecule. While most are lifestyle-related, one of the main ones is out of your control, namely aging.

As you age, your body produces less NO, namely because the enzyme needed to produce NO becomes dysfunctional. “By the time you’re 40, you have only 50 percent of the NO as you did when you were 20,” Bryan says, adding, though, that exercise can help prevent this.

The second major factor is a diet deficient in nitrate, which is found in plant foods like leafy greens, beets, and celery. “If you’re not eating enough of these foods, you’ll become NO deficient,” Bryan adds. And while one can compensate for the other – in other words, a good diet can compensate for enzymatic issues as you age – that becomes impossible when you have existing health conditions.

What else might disrupt your body’s NO production? Bryan ticks off a list of other factors: Using antiseptic mouthwash, taking antacids, eating genetically modified foods exposed to glyphosate, brushing your teeth with fluoride toothpaste, being sedentary, and having an active oral infection or chronic inflammation in the body from health conditions like heart disease, rheumatoid arthritis, lupus or any other autoimmune condition.

How to eat for your body’s Nitric Oxide needs

You can’t halt the brakes on your birthdays, but you can change some of your habits, starting with eating a plant-based, nitrate-rich diet. “When consumed, the nitrates in these foods can be converted to NO, giving a temporary boost to the NO levels in your body,” Kwik-Uribe says. In fact, Bryan says that about 50 percent of your daily NO product comes from your diet (and bacteria in your mouth).

Foods that are the highest NO converters include kale, Swiss chard, arugula, spinach, spirulina, bok choy, beets, cabbage, cauliflower, kohlrabi, carrots and broccoli. An insider tip from Bryan? Add lemon juice to cooked greens and salads to aid the conversion to NO.

Getty Images/EyeEm

Other dietary fixes include eating foods high in arginine, which is a precursor for NO, Kwik-Uribe. That includes seeds, nuts and chickpeas. (Note that people often pop NO supplements, which actually contain arginine versus NO, but study results have been mixed.) Getting the right amount of vitamin C can also keep your NO levels healthy, one reason citrus fruits are recommended, and there’s evidence that cocoa flavanols in dark chocolate can increase NO availability within the body. Drinking red wine and green and black tea can also aid NO production.

A surprising caveat, though: Nitrate levels in foods depend on where you live: In one study, Bryan analyzed the nitric content of leafy greens from different cities to figure out how much you would need to eat to get the benefits. Unfortunately, nitrate levels depended on geographic location. While Dallas and Los Angeles had the highest levels, the same type of vegetables in Chicago and New York City had 40 to 50 times less. In other words, “whereas you might have to eat six stalks of celery to get enough NO in Dallas, you’d have to eat maybe 70 stalks in New York City,” Bryan says.

And those were conventionally grown vegetables. Nitric oxide levels were even lower, by as much as 10 times less, in organic vegetables. “While organic is beneficial in that you’re not getting exposed to herbicides, because of restrictions in nitrate fertilization, these vegetables become depleted in nitrates,” he says.

So how do you know if you’re giving your body all the NO it needs? Unfortunately, there’s no simple or reliable test of your NO status, Kwik-Uribe says. Yet there are NO salivary test strips on the market, including one Bryan has developed, that could give you at least some reference.

Bottom line? Without enough NO on board, your body won’t stay – or get – healthy so follow Mom’s advice and eat those veggies.