Dietary Supplement Non-GMO The health of the vascular system is overlooked in the effort to support sexual function in aging men. Blood flow through the delicate lining of the arteries (the endothelium) is essential to sexual arousal. So it should come as no surprise that endothelial function is closely associated with male sexual capacity. Life Extension has discovered supportive clinical research for a scientifically validated, natural dietary supplement formula to promote endothelial function and blood flow to the place men need it most — for maximum performance. The ingredients found in Prelox® Natural Sex for Men have yielded compelling and highly satisfactory results in five independent clinical studies. The patented blend of the following ingredients positively affects the male physiology in these three ways, to provide optimal support: Pycnogenol (standardized French maritime pine bark extract) activates endothelial nitric oxide synthase (eNO-S), the enzyme required to make nitric oxide. Nitric oxide (NO) relaxes the vessels that enable efficient blood flow — the key to healthy male sexual activity and overall vascular health. Pycnogenol further amplifies this relaxing effect by extending the amount of time nitric oxide remains in the bloodstream. L-Arginine is the biological precursor to nitric oxide synthesis in the endothelium. It interacts synergistically with Pycnogenol to sustain nitric oxide levels sufficient for healthy sexual function. Icariin, a natural botanical compound used in traditional Chinese medicine, has been shown to deactivate the enzyme normally responsible for winding down male sexual response, further promoting sustained activity.