Nitric oxide (NO) is a ‘signaling molecule’, whose biological functions regarding blood vessel dilation were discovered relatively recently, in the 1980’s. It created a stir in the scientific community, as it was previously an unknown factor in vasodilation (the expansion of blood vessels). The discovery was so significant that it was named the molecule of the year in 1992, and an entire journal was devoted to the compound’s study. Since then, it has been found that NO plays a major role in a variety of biological processes affecting the immune, nervous and cardiovascular systems.
What Does It Do?
NO works by relaxing the vascular smooth muscles (the mechanisms responsible for the distribution of blood within the body), thus increasing the volume of blood coursing through the body’s blood vessels. Nitric oxide is generally synthesized naturally by the body. It must be produced by exogenous means. That means NO must be synthesized either naturally by the body or by consuming certain foods or supplements. Foods that are rich in L-citrulline, like watermelons, onions, garlic and liver are conducive to the production of NO.
Although there are no direct nitric oxide supplements, l-citrulline is the amino
acid that the body uses to convert into nitric oxide. L-citrulline supplements are readily available over-the-counter online, at vitamin stores and supermarkets.
Uses
Because NO allows more blood to flow through the body, supplements containing l-citrulline have proven to have many uses (from treating patients with heart problems to alleviating high blood pressure). It has also been found be an excellent exercise supplement and if taken in conjunction with a good exercise regime can enhance performance by allowing for harder and more powerful training sessions. Since looser blood vessels allow more blood flow, it boosts the amount of oxygen and other nutrients the body’s muscles, heart and other vital organs receive – alleviating workout fatigue and increasing stamina. This is essentially how NO supplements can assist with weight loss.
False Claims
Many supplement manufacturers will claim that their product can ‘pump up’ muscles and melt away fat; this isn’t the case. Although these supplements can be useful, they are certainly not a miracle weight loss drug. It should also be noted that using NO supplements does not particularly help well trained athletes who are already in shape. Nonetheless, these supplements have proven useful in helping people who are looking to get in shape by following a work-out schedule, particularly with individuals who have trouble producing NO on their own. Since the body produces less Nitric Oxide as a person gets older, NO supplements are particularly useful for older patients.
Study
A recent study of 16 older male cyclists who were given the supplements (aged 50 to 73) has shown a nearly 17% increase in anaerobic threshold (a measurement of lactic acid used to quantify workout intensity). The control group was given a placebo and showed no improvement. Granted, this is still a very small research group and further study is needed for more conclusive results.
Price
L-citrulline supplements are generally available in a power form (to be mixed with water or a sports drink), but it can also come in lozenges or pills. These supplements can range in price from $10 to $200, and may contain other vitamins and minerals. It is advisable when purchasing a supplement in general, that it bears the logo of an independent testing laboratory (e.g. Consumer Lab, USP, and International). The best range and best prices can be found at amazon.
There are many practical medical applications for nitric oxide supplements, and given its function with vasodilation, it may be indirectly useful for weight-loss. However, it is by no means a weight-loss drug – it must be taken with regular exercise and a healthy diet in order to be effective in some people.