Nitric oxide is a messenger in your body — it’s released to tell various systems what to do. Most notably, nitric oxide signals the circulatory system to relax, lowering blood pressure and reducing tension. In other words, obtaining sufficient nitric oxide will help you maintain your heart health and blood pressure, which is why, as a personal trainer and nutritionist, I encourage my clients to make it a priority.
Some people take nitric oxide supplements, but for most, it’s much easier to just eat foods high in nitric oxide, consuming it through your regular diet. (Fun fact: most foods aren’t actually high in nitric oxide itself, but rather in its precursors, the raw ingredients used to synthesize nitric oxide inside your body.) In this article, we’ll give you a list of some of the best sources, plus more information about nitric oxide than you ever knew existed. Let’s get started!
9 foods high in nitric oxide to include in your diet
- Kale: Kale and other leafy greens are high in nitrates, which are converted to nitric oxide in the body. Kale contains about 600 milligrams of nitrates per kilogram of kale. Note: The study from which this nitrate data originates found that leafy greens in Croatia (the region studied) have significantly higher nitrate contents in autumn than in spring. I’m referring to the spring numbers.
- Spinach: There’s good news for kale haters. Spinach actually has a higher nitrate content than kale — a little over 700 mg per kg of spinach.
- Beets: Beets are also extremely high in nitrates, with an average of 495 mg per 100-gram serving. That’s quite a bit more than either spinach or kale.
- Cucumbers: Cucumbers are high in L-citrulline, an amino acid and precursor to nitric oxide. In other words, this is an ingredient your body uses to create nitric oxide.
- Melons: All types of melons, from watermelons to cantaloupe to honeydew, contain L-citrulline. Watermelon has the most, and rarer varieties, such as yellow and orange watermelon, contain even more than red watermelon.
- Cabbage: Cabbage is another leafy green high in nitrates. It’s best eaten cooked or sliced thin and tossed in a coleslaw, as it’s not a typical salad green. It has around 700 mg/kg of nitrates.
- Broccoli: Broccoli is not a leafy green, but it also contains substantial amounts of nitrates — about 40 milligrams in a 100-gram serving. (That’s 400 for a kilogram, to compare directly to the leafy green, although few people will eat a kilogram of any vegetable in a day.)
- Lettuce: Lettuce, like most of the other leafy greens, contains about 700 mg/kg of nitrate. Although lettuce usually has fewer nutrients than darker greens like spinach, it’s keeping up in terms of nitrates.
- Peanuts: Peanuts are high in L-arginine. L-arginine is the direct precursor to nitric oxide; L-citrulline turns into L-arginine first.
What are the benefits of nitric oxide?
Improved heart health
Nitric oxide is commonly recommended for heart health. Although some of the scientific details are still being worked out, people whose bodies struggle to get nitric oxide to their cardiovascular system have higher risks of cardiovascular disease.
Lower blood pressure
An article in Hypertension, a journal published by the American Heart Association, says nitric oxide can reduce the risks of hypertension, aka high blood pressure. It also says that “Attempts to evaluate a role for NO [nitric oxide] in experimental hypertension have been extensive; however, results of these studies have been highly divergent.” In other words, studies have shown that nitric oxide affects hypertension, but they come up with different reasons why.
Recovery
Some people claim that nitric oxide also improves muscle recovery and recovery from injuries. There isn’t yet conclusive scientific evidence to support this, but it’s certainly possible; nitric oxide helps relax blood vessels, delivering more blood and oxygen to healing areas, and it may also relax the muscles, which can contribute to healing and recovery. Again, however, this benefit has not been proven.
How do you know if you are deficient in nitric oxide?
Nitric oxide deficiency can be challenging to diagnose. Symptoms include high blood pressure, elevated blood sugar, increased soreness, and erectile dysfunction, but several other conditions could cause similar symptoms.
The only way to be certain whether you have a deficiency is a blood test, but you can also experiment: try eating more foods that contain nitric oxide, or even taking a nitric oxide supplement, and see if your symptoms improve. If not, the issue might be something other than a nitric oxide deficiency.
When should you take nitric oxide supplements?
If you conclude that you have a nitric oxide deficiency and it’s difficult for you to add more leafy greens to your diet, you might want to consider taking a nitric oxide supplement. Your doctor may encourage you to take a supplement if a blood test shows a deficiency. If you already eat large amounts of leafy greens in your diet, you probably don’t need a supplement, and it’s possible it could even be harmful.
Is there any risk of consuming too much nitric oxide?
It is possible to have too much nitric oxide. Nitric oxide is a free radical, which means it’s more reactive than most molecules in your body. Excessive nitric oxide can react with other molecules, leading to oxidative stress and inflammation.
This is a little bit confusing to research because nitric oxide is also found as a gas in car exhaust, and the gas is extremely toxic and dangerous. It can cause headaches, blurred vision, and lung damage. In the atmosphere, it can also be converted into nitric acid, causing acid rain. And yet, the exact same molecule plays a critical role in your body. Inhaled, it’s toxic; eaten or synthesized in your body, it’s necessary. The way something is ingested can matter a lot.
Frequently asked questions
What is the fastest way to increase nitric oxide?
The fastest way to increase nitric oxide is to take a supplement. It takes time to digest the nutrients in food; taking a supplement reduces that time. Most supplements still contain the precursors to nitric oxide rather than nitric oxide itself, since, in pure form, it’s a gas.
What drinks are high in nitric oxide?
Watermelon juice is higher in L-citrulline than anything else. A green smoothie or even a drink made with greens powder can rapidly increase your nitrate levels. A watermelon, spinach, and peanut butter smoothie would be the best drink for nitric oxide, but I don’t think anyone is eager to try that combination!
What fruit has the highest nitric oxide?
Yellow watermelon has the highest levels of L-citrulline, an important precursor that helps your body make nitric oxide. If you can’t find yellow watermelon, ordinary red watermelon is your best bet, although any melon is good.
