Brief Answer: Blood flow to the penis rises when excited. Detailed Answer: Hello friend, Blood flow to the penis is normally achieved when one is sexually stimulated. Depending on the age of the individual, the nature and intensity of the stimulation needed to erect the penis varies. While a young adult can easily achieve erection, an aged male may not get such easy erections. A young adult can easily get excited and get erection by the mere thought of a female, her nude body parts, seeing porn videos etc. But an elderly man may need actual sexual contact with a female, touching the penis with his or her hand or even stimulating it manually as is done during masturbation. During a shower, or while doing other works, as you mentioned about brushing the teeth, the penis is not expected to be erected and so it hangs as you narrated. Better girth is achieved by increased blood flow only. Therefore it happens during sexually stimulating the penis as is happening in masturbation or sexual intercourse. Penis is formed by muscles supplied with more sensitive nerves. The stimulation of it by hand or friction during sex act can take the sensations to the brain and can increase its girth by increased blood flow needed to strengthen it and thus enabling it to penetrate the female vagina. Better nutrition can improve the whole musculature and that can also influence the girth of the penis. Hope you are satisfied by my answer. If so then you can close the query by reviewing it accordingly. With best wishes, Dr. C. J. Varghese Homoeopath

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