Nitric oxide

Nitric oxide can increase blood flow and reduce blood pressure. Supplements that increase nitric oxide production may also be beneficial for managing certain health conditions.

Nitric oxide is produced naturally by the human body and is one of the most important molecules for blood vessel health.

It’s a vasodilator, meaning it relaxes the inner muscles of your blood vessels, causing the vessels to widen. In this way, nitric oxide increases blood flow and lowers blood pressure.

Supplements that increase nitric oxide in the body make up one of the most popular supplement categories today.

These supplements don’t contain nitric oxide itself. However, they contain compounds that your body can use to make nitric oxide and have been shown to provide many benefits for health and performance.

Benefits of taking Nitric Oxide supplements:

• May decrease muscle soreness

A form of L-citrulline called citrulline malate not only increases nitric oxide production, but also decreases muscle soreness.

Muscle soreness is an uncomfortable experience that tends to occur after strenuous or unaccustomed exercise.

This soreness is referred to as delayed-onset muscle soreness and usually feels the strongest 24–72 hours after exercise.

In one 2010 study, 41 people were randomized to receive either 8 grams (g) of citrulline malate or a placebo 1 hour before performing as many repetitions as possible on a flat barbell bench press.

Those given citrulline malate reported 40% less muscle soreness at 24 and 48 hours after the exercise, compared to those who took the placebo.

Citrulline malate increases nitric oxide production, which increases blood flow to active muscles. In turn, citrulline malate is thought to increase nutrient delivery and clear waste products that are related to muscle fatigue, such as lactate and ammonia.

However, a later study on the effects of citrulline after leg exercises did not find citrulline malate helpful for the treatment of muscle soreness.

Another review of 13 studies showed that while citrulline could reduce muscle soreness 24 hours and 48 hours after exercise, it did not improve muscle soreness 72 hours after exercise.

Therefore, the ability of citrulline malate to decrease muscle soreness may depend on the dose, exercise, and timing. However, more research on this is needed.

• Lowers blood pressure

  People with high blood pressure are thought to have an impaired ability to use nitric oxide in their bodies.

  High blood pressure occurs when the force of your blood pushing against the walls of your arteries is consistently too high. It is defined as systolic blood pressure above 130 millimeters of mercury (mmHg) and/or diastolic blood pressure higher than 80 mmHg.

  Over time, high blood pressure can lead to health issues such as heart disease and kidney disease.

  It has been shown that a diet high in fruits and vegetables decreases blood pressure and therefore lowers the risk of disease.

  This has led researchers to test the beneficial effects of certain compounds found in fruits and vegetables on blood pressure levels.

• Boosts exercise performance

  Nitric oxide is involved in many cell processes, including the widening of the blood vessels, or vasodilation. Wider blood vessels help increase the delivery of nutrients and oxygen to working muscles during exercise, thus enhancing exercise performance.

  This has made nitric oxide supplements popular among athletes and recreational gym-goers.

  These supplements often contain several ingredients that are said to increase nitric oxide, such as nitrate or the amino acids L-arginine and L-citrulline.

  In many analyses, nitrate has been shown to improve exercise performance in cyclists, runners, swimmers, and even kayakers.

  On the other hand, L-arginine has not proven to be effective for improving exercise performance in many studies.

  According to one older study, this may be because much of the L-arginine that is ingested is metabolized or broken down before it gets a chance to reach the bloodstream

• May help manage type 2 diabetes

  Nitric oxide production may be reduced in people with type 2 diabetes.

  This leads to poor blood vessel health, which can lead to conditions like high blood pressure, kidney disease, and heart disease over time.

  Therefore, supplements that increase nitric oxide may have important implications for diabetes treatment and disease prevention.

  One review of 10 studies found that supplementing with L-arginine could significantly reduce insulin levels in people without diabetes.

  Another 2012 study in 144 people looked at the effects of L-arginine on preventing or delaying the progression of type 2 diabetes.

  While L-arginine did not prevent people from developing diabetes, it did increase insulin sensitivity and improve blood sugar control .

  However, other research has found no effect of L-arginine on fasting blood sugar levels and blood sugar control in people with diabetes.

  Therefore, until more research is available, it is premature to recommend taking L-arginine supplements to treat or manage diabetes.