Semen quantity and quality varies not just between different men, but with the same man over the course of the month, the year, and over his whole life. Variances in color, viscosity and smell from month to month are normal, depending on stress levels, vitamin and mineral intake, hydration levels and hormone fluctuation. However, some changes in semen may reflect an underlying pathology such as a prostate disease or an STD. Learning more about penis health, nutrition, and going to the doctor when necessary, are all important factors for men to consider.

Color

There is a right way and a wrong way for semen to look. In healthy men semen appears, normally, as a milky white color. But when semen color changes, it can mean many different things. Pink or brown semen occurs because blood has mixed with the seminal fluid. According to Dr Rob Hicks on the BBC Health website, most often pink or brown semen occurs because of an infection, either in the urethra, the prostate or the seminal vesicles. Other causes include trauma, urethral polyps, prostate cancer and prostate surgery. Yellow or green semen may be a sign of a urinary tract infection. Chlamydia and gonorrhoea are two STI's known to cause yellow and/or green semen. Other possible causes of yellow/green semen include the presence of high-dose vitamins, jaundice, and even urine.

Smell

Semen has a distinctive smell which could be described as metallic. This odor comes from the high concentrations of zinc found in semen. Zinc is an important mineral in the human body for cell growth, wound healing and immune function. For men zinc also plays a very specific function in protecting male fertility and sexual health. Zinc concentrates in the prostate tissue and acts as a local regular for healthy cell growth, helping to prevent benign prostate growth and cancerous changes. Zinc also acts as an antioxidant and antiseptic for both the prostate and the sperm. Though this micromineral is important for male health, it is not found in a huge variety of foods -- the best food sources being oysters, scallops pumpkin seeds, oats, sesame seeds and chia seeds; not foods that men would eat in huge quantities every single day. Increasing these foods in the diet, or taking dietary supplements containing 15-30 mg of zinc daily, may cause a man's semen to intensify in smell. If the semen smell changes to become malodorous and foul-smelling, it may be a sign of an infection and should be checked out by the doctor.

Quantity

Semen volume can vary a lot in men, especially as they age. The WHO states that semen volume tends to fluctuate between 1.5 ml to 7 ml in most men. Anything less than 1.5 ml may be a sign of infertility, as well as possible health problems. Often how much semen a man produces is not something he thinks about very much until he is not producing enough of it. Reasons for this can be as simple as dehydration, or as complicated as heart disease, cancer, blocked seminal vesicles and prostate disease. Researchers from Queen's University in Belfast, Ireland, found during a clinical study that men with diabetes were more likely to suffer from low semen volume and poor sperm motility. Obesity, a high-soy diet and normal aging also contribute to low semen volume, due to increased estrogen levels which affect semen production.

Taste

Whether your semen tastes like fruit or foot might not make that much difference to you, but it might to your partner. The flavor of semen varies quite a lot between different men, and women indicate that if a man's spunk doesn't taste nice, they are less willing to perform oral sex. In fact, as many as 85% of women do not enjoy the taste of their partner's semen and the reason for this may have a lot to do with his lifestyle. Male ejaculate isn't just made up of sperm -- only 2-5% of it is. The other 95-98% is comprised of water, amino acids, vitamins (ascorbic acid), minerals (zinc, selenium, potassium, magnesium), hormones, enzymes and sugars (fructose). Hence, not getting enough nutrition in the diet each day may affect the way that semen tastes. In addition, smoking tobacco, eating red meat, taking drugs and a high alcohol intake are known to make semen taste bitter or sour. Natalie Ingraham, M.P.H., states on The Kinsey Institute's blog that oranges, pineapples, grapefruit, parsley, wheatgrass, celery and some spices may have specific functions in improving the taste of a man's spunk.

Penis Health crèmes

Health crèmes designed specifically for the health of the male reproductive system can provide needed nutrition and support that cannot be gained from the diet. Specialist penis creme formulas (most professionals recommend Man1Man Oil) provide vitamins, minerals and antioxidants that can be absorbed directly into the bloodstream and into the local tissues. Vitamin C, E, A, D, L-carnitine, L-arginine, alpha lipoic acid and shea butter all have shown in studies to support multiple levels of male sexual health. Many of these, especially vitamin C, E and L-arginine, are important for the health of the seminal fluid and semen production.