Are nitric oxide supplements even safe to take? Many people seem to be taking nitric oxide supplements this day. Are these types of supplements beneficial for the human body? Indeed nitric oxide is safe, in fact, it is a necessary component for the human body to have to stay healthy. It is produced by almost every cell in the human body. The molecules are very important for healthy blood vessel function. They help the blood vessels to widen and allow the blood to flow through the body. But these molecules do not contain nitric oxide in their structures.