A man’s nether region should not only be judged based on how it performs in his love life but in his everyday life as well. A healthy penis is vital to ensure the entire male body is fully functioning and at optimal performance to complete daily processes. A penis’s sensitivity, size, and erection are all associated with male health in terms of what’s normal and what’s not, which may serve as an early indicator of problems in other areas.

1. Shrinkage from Too Cold or Too Hot Temperatures

Sperm production thrives in temperatures that are slightly below normal body temperatures. Men will often notice when they are cold, their penis shrinks. According to Harvard Health Publications, the blood vessels in the penis shut down because of the cold temperatures, but it will still be able to expand to its usual size once the blood flow begins. Going from slightly below normal body temperature to an increase by even two, three, or four degrees, can negatively affect sperm and testosterone production. Men are advised to keep their genital area cool by avoiding tight pants and warm, moist places like hot tubs for long periods of time if they are having trouble conceiving with their wives.

2. Prostatic Congestion, or “Blue Balls” During Sexual Arousal

Men may frequently say they have “blue balls,” medically known as prostatic congestion, especially when sexual arousal is not followed by an orgasm. The testicular aching or lingering sensation of discomfort a man feels is due to the uneven blood flow that leads to an increase in the volume of blood trapped in the genital. This leaves the penis erect and the testicles engorged until the volume of blood in the genital is reduced and the penis and testicles return to their usual size, says Sexual & Reproductive Health Matters.

3. Alcohol Use and Erection

Consuming too much alcohol is not only bad for your liver but for your penis's health. A man’s ability to get an erection is hindered by drinking high doses of alcohol, or blood alcohol concentration (BAC) above .08, according to McKinley Health Center at the University of Illinois. The dehydration associated with drinking causes less blood volume and a rise in angiotensin — the hormone associated with erectile dysfunction. However, for some men, particularly for younger men, heavy drinking can reduce anxiety and facilitate erections.

4. Smoking and Penis Arteries

It is a known fact that smoking cigarettes contributes to the development of atherosclerosis, or the buildup of plaque inside the arteries. Cigarettes clog the heart’s arteries, including those that fill the penis with blood during erections. The toxic chemicals in cigarette smoke can damage blood vessels that may lead to erectile dysfunction, says the National Male Medical Clinics. Smoking can also cause damage of the penile tissues that will impact the ability of a man’s penis to function normally.

5. Decline in Penis Sensitivity

A decline in penis sensitivity is completely normal for a man as he ages, although how much sensitivity is lost remains undefined. The sensitivity of the penis is evaluated by the least amount of stimulation a man is able to feel. According to the department of psychology at the University of Texas at Austin, age-related decrease in libido is usually attributed to a decline in testosterone levels and changes in receptor site sensitivity to androgen. Sensitivity starts to decline from age 25 and on, with the sharpest decline seen in those between age 65 and 75.

6. Erections Keep Penis in Shape

Every time you get nocturnal penile tumescence, or “morning wood,” your penis is actually staying in shape. The muscle of the penis must receive oxygen via blood flow that causes it to engorge and become erect. If men don’t experience regular erections, the penile tissue can become less elastic and shrink, which could make the penis one to two centimeters shorter.

7. Vasectomy Doesn’t Stop Release of Semen — Right Away

Men may opt for a vasectomy to prevent the release of sperm when he ejaculates in order to either eliminate the risk of pregnancy, or for other personal reasons. After the surgical procedure, the sperm count begins to gradually decrease, taking anywhere from two to three months for sperm to no longer be present in semen, according to Medline Plus. Until a doctor confirms your semen sample is free of sperm, use protection.

8. Penis Home to Bacteria

The skin of the penis is an ideal environment for bacteria to multiply, but the amount of bacteria depends on whether the man is circumcised or not. A study in the journal American Society for Microbiology found there were fewer kinds of bacteria on the penises of a group of men who got circumcised, compared to the samples taken when they were uncircumcised. The Centers for Disease Control and Prevention notes several studies found circumcision changes the bacteria ecology of the penis, which may explain why snipping the foreskin reduces the risk of HIV infection. The theory behind this is that anaerobic bacteria — bacteria that do not live or grow in the presence of oxygen — could cause the immune system to react in a way that makes cells more vulnerable to HIV infection in uncircumcised penises.

A healthy penis is not just about how well a male performs in the bedroom, but also about how it functions on a day-to-day basis. If the penis is not able to get erect, it could reflect problems that go beyond sex, an indicator of problems with other organs in the body. Remember men, your penis is a dipstick indicator of health.