A man will not experience the deficiency of a particular nutrient when he consumes various types of food. If someone has felt that there is a health problem for him, it is better not to rush to take supplements. Try to first improve your diet by reducing the intake of foods that are less good for health and increase food intake is very good. You can get it consulted with your nutritionist. If you are experiencing a deficiency state of vitamin/mineral and indeed require external supplementation, your doctor will give it according to the dose that suits your needs at that time. When you then go to www.amazon.com/Nitric-Oxide-Supplement-Concentration-Comprehensive/dp/B00DXOIKM0, does it mean that you are seeking only the best quality supplement products?
One thing to note in taking supplements is the risk of less controllable toxicity because of the lack of interaction with other substances. Intake of vitamins and minerals from food sources is less able to provide toxicity effects because in a food source there are a variety of other substances that can provide interaction reduction toxicity of a vitamin/mineral.