According to Dr. Ridwan Shabsigh, a man's sexual health is the portal to understanding his overall health and well-being. Sexual dysfunctions are not only associated with major medical illnesses—such as diabetes, high blood pressure, heart disease and obesity—they can also be predicators of health problems to come, he says. The good news, Dr. Shabsigh says, is that the majority of men can improve sexual performance without medical interventions. Dr. Oz talks to Dr. Shabsigh about ways to improve a man's sexual health, which he outlines in his book, Sensational Sex in 7 Easy Steps: The Proven Plan for Enhancing Your Sexual Function and Achieving Optimum Health.

With the proper diet, exercise and healthy body weight, Dr. Shabsigh says many sexual dysfunctions in men can be dramatically improved. He says studies have shown that abdominal obesity, or excessive belly fat, is known to have an enzyme called aromatase that converts testosterone to estrogen. These increased levels of estrogen and decreased levels of testosterone lead to fatigue, low body muscle mass, high body fat mass and low muscle power—known as the metabolic symptoms of low testosterone—as well as sexual symptoms like low sexual desire, erectile dysfunction and ejaculatory dysfunction.

In addition to losing weight and eating right, Dr. Shabsigh says supplements that benefit the vascular system can boost one's sexual health. "Anything that is healthy for your vascular system would be healthy for your sexual function and erectile function because the [male] genital organ, the penis, is a vascular organ," he says. To that end, Dr. Shabsigh recommends supplements such as L-arginine, ginseng and ginkgo biloba. He also says nutrients like zinc and selenium, which benefit prostrate health, are also good for sexual function.

Dr. Shabsigh also says a man's mental health factors into his sexual health in a big way. Major psychological issues, such as depression, anxiety and stress, affect sexual function and overall health negatively, he says. However, men who take steps to improve their sexual health often boost their mental health simultaneously, Dr. Shabsigh says. "Successful, enjoyable sexual health and sexual function has a very great mental health value," he says.

In the quest for better sex, Dr. Shabsigh says it takes two to tango. He says that improving one's relationship with their partner is a learned skill—and it's essential for intimacy and great sex. "We take it for granted that, 'This is my wife and we should have a good relationship.' No—there are things you can do to improve your relationship and there are things she can do to foster the relationship," he says.

• Sensational Sex in 7 Easy Steps: The Proven Plan for Enhancing Your Sexual Function and Achieving Optimum Health by Dr. Ridwan Shabsigh

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