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What Men Should Know About Nitric Oxide Supplements

Many men want to stay as healthy as they can, and they look for ways to keep their hearts strong, their energy levels high and their bodies performing at their best.

You may be considering or taking nitric oxide (NO) supplements to try to improve your athletic performance or your overall health. What impact can these supplements have? And what are the risks

We talked to Jacquelin Danielle Fryer, a registered dietitian specializing in sports nutrition at Banner Sports Medicine Scottsdale, to learn more about nitric oxide and how it might impact men’s health.

What to know about nitric oxide

One important thing to note is that nitric oxide is different from nitrous oxide, which is commonly called laughing gas. They are completely different compounds. 

“Nitric oxide is a short-lived gas molecule made from nitrogen and oxygen that your body naturally produces,” Fryer said.

Nitric oxide may help protect against heart problems and promote vitality. It sends messages between cells and plays a role in blood circulation and the way your immune system responds to infection and inflammation. It helps your nerves transmit signals and may support brain health. 

Nitric oxide can also help you maintain a healthy blood pressure because it relaxes the blood vessels and lowers the strain on the heart. It helps your blood vessels stay healthy and flexible. Because of this, it may also help men with erectile dysfunction and improve sexual well-being.

Because nitric oxide relaxes and widens the smooth muscles inside blood vessel walls, it may improve blood flow. Better blood flow may improve physical performance by bringing more oxygen and nutrients to the body.

“Because nitric oxide delivers more oxygen and nutrients to muscles, athletes may benefit from it because it improves endurance, reduces inflammation and fatigue and helps muscles repair and grow,” Fryer said. Nitric oxide may also speed recovery by removing metabolic waste, increase stamina and make workouts more productive and enjoyable.

Sources of nitric oxide

Your body makes nitric oxide naturally, and some foods can help:

  • Red meat, poultry and seafood can boost your nitric oxide levels.
  • Vegetables such as spinach, arugula, beets, kale and leafy greens are rich in nitrates, which your body can convert into nitric oxide.
  • Fruits like watermelon, oranges and grapefruits contain compounds that help your body make nitric oxide.
  • Pomegranates may help your body synthesize nitric oxide.
  • Garlic contains allicin, a compound linked to increased nitric oxide production.
  • Some nuts and seeds, including sunflower seeds, almonds and walnuts, contain nutrients that support nitric oxide levels.
  • Dark chocolate may increase nitric oxide levels.

“You can get plenty of nitric oxide without supplementation if you eat a daily, balanced diet made up of real, natural food,” Fryer said.

Keep in mind that the nitrates you can find in food are not the same as nitrites. Nitrites are often used to preserve meat like bacon and ham. They are what gives those processed foods a pink or red color. 

Eating too much saturated fat and food with nitrites can actually lower nitric oxide levels. So steer clear of processed meat, processed food, fried food, cooking oils and palm oil.

Choosing a nitric oxide supplement

You may want to take supplements to maintain good levels of nitric oxide and improve your physical performance and well-being. It’s important to talk to a health care provider before you start taking any supplement. 

Keep in mind that even if you choose supplements, you should still follow healthy lifestyle habits:

  • Choose a balanced diet
  • Get regular exercise
  • Drink plenty of water
  • Manage stress
  • Limit or eliminate alcohol and tobacco
  • See your health care provider for regular checkups

Many men try these supplements:

  • L-arginine, an amino acid that may help your body produce nitric oxide
  • L-citrulline, a non-essential amino acid that your kidneys can convert into L-arginine and may be more effective than L-arginine
  • Nitrate supplements, since your body can convert nitrates into nitric oxide
  • Beetroot extract, a natural source of nitrates 
  • Combinations of these supplements and, sometimes, antioxidants

If you’re choosing a nitric oxide supplement, talk to your health care provider about the correct dose based on your needs, health and medication. It’s especially important to consult a provider if you have heart or blood vessel issues, kidney problems or allergies or if you are taking medication.

Dosages for supplements

“The recommended pre-workout L-arginine dose is three to six grams, but taking over ten grams at once can cause stomach issues. To maintain arginine levels, it’s better to take three spaced doses totaling 15 to 18 grams a day,” Fryer said.

If you take L-citrulline, she recommends six to eight grams about an hour before exercising to see the best results. “If you are not exercising that day, you can split the dosage into smaller increments.”

Look for supplements from trustworthy brands that meet quality and purity standards from a third party like, NSF or USP. Check the label to make sure it lists the ingredients and their amounts.

Begin with a low dose, see how your body responds and watch for any side effects. You can gradually increase your dose based on the product’s directions and your provider’s recommendations.

It’s important to be consistent and take supplements regularly. Depending on the type, taking them with meals or before exercising may be best.

Possible side effects

Most men don’t experience side effects from nitric oxide supplements. But sometimes, they can cause:

  • An upset stomach, nausea, stomach pain, bloating or diarrhea. Adjusting the dosage or taking supplements with food usually relieves these symptoms.
  • Headaches.
  • Low blood pressure.
  • Interactions with blood thinners or erectile dysfunction medicine.
  • Increased risk of bleeding.
  • Blood vessel damage, if you use them for a long time.
  • Allergic reactions such as skin reactions, itching or more severe symptoms. If you have signs of an allergic reaction, stop taking the supplements and talk to your health care provider.

“It’s important to talk to a health care provider about benefits and risks before you take nitric oxide supplements,” Fryer said. “Men who have underlying health conditions, low blood pressure or heart disease or who take medication for erectile dysfunction or other cardiovascular conditions, should avoid these supplements.”

The bottom line

Nitric oxide is a gas that your body makes naturally. It helps relax your blood vessels, so it may help lower blood pressure, improve athletic performance and enhance sexual functioning in men with erectile dysfunction.

You can choose a healthy, balanced diet to help your body make the nitric oxide you need. Or you can talk to your health care provider about supplements that can help boost your body’s nitric oxide.

Reach out to Banner Health if you would like to connect with a provider who can help you understand the pros and cons of nitric oxide and other supplements.

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