Tristan- If you’re thinking that a 3 pack of condoms costs around $5 and Mountain Dew is only $1.99 for the 2-liter, so why not save yourself $3 on your contraception, think again! Pay the extra money! Mountain Dew does not kill your sperm, lower sperm count, make your penis smaller, or shrivel up your testicles (unless it’s ice cold and placed directly on your testicles, then there might be some temporary shriveling).

I always love a good urban legend. I once got a co-worker to believe coffee shrank his penis. All I needed to do was use a bunch of big words in a meaningful way. (It also helps being a paramedic, as people tend to take your medically protestations more seriously and you have a bigger store of medical terms on hand.  It provides quite a bit of fun, I can tell you.) I made sure to use medical terms he didn’t understand, and BAM! He stopped drinking coffee for weeks. He figured it out a few weeks later and never believed anything I said again. I can only assume this myth came about in a similar way. That being said, I’m never one to just say something without explaining why. Let’s look at Mountain Dew and see why exactly it doesn’t kill sperm.

Mountain dew has numerous ingredients. The two that get mentioned the most in this myth are caffeine and Yellow dye #5, also known as Tartrazine.

Let’s start with caffeine. Mountain dew contains 54mg of caffeine in a 12 oz can.  That might seem like a lot since coke has 34mg per 12 ounces, Dr. Pepper has 41, and Pepsi has 38. If caffeine was truly the cause, drinking coffee would also have to be out. The average cup of drip coffee has 217mg per 12 ounces, about 4 times more than the Mountain Dew! So for comparison’s sake, Mountain Dew doesn’t contain very much caffeine, compared to other things many commonly drink.

The idea that caffeine affects the chances of having a baby is true. There have been several studies that show women who drink 3 or more cups of coffee a day have a decreased chance of becoming pregnant compared to those who don’t drink coffee. Unfortunately, the exact nature of why caffeine affects conception rates is unknown. Because those who drink more caffeine also tend to have unhealthier lifestyles, many of the studies site life style as the reason and not necessarily the caffeine itself.

The idea that caffeine intake affects sperm in some way seems to be dose related. The Chemical Health Hazard Assessment Division of the Canadian Bureau of Chemical Safety (they really need to work on that name!) reviewed  all the current studies on the subject and found that they showed that if a man drank one or two cups of coffee per day, he would have an increase in his sperms motility (the ability to move) and density. If you drank 4 or more cups and also smoked more than 1 pack of cigarettes per day, your sperms motility and density would decrease. The study concluded that only heavy smokers need to worry about drinking too much coffee and sperm problems. The authors went on to say that those sperm problems would most likely not affect fertility.

In the end, it appears you would have to drink about eleven 12 ounce cans of Mountain Dew (or a similar amount of other popular caffeinated soft drinks) and smoke over 20 cigarettes before your sperm would be affected. If you did, that affect wouldn’t cause any fertility issues. At that point, I would worry more about your cancer and diabetes risk, not to mention the effects on your heart and lungs, before I would worry about your sperm.

Now let’s look at the other proposed cause of sperm problems and Mountain Dew- Tartrazine (yellow dye #5). Tartrazine has been used in food, ice creams, drugs, and many other products since 1916. Most all of Tartazine you put in your body will come out in your urine. Very little is actually metabolized by our bodies. The European Food Safety Authority re-evaluated the effects of Tartrazine in 2009. What they found was that there are no adverse effects on reproduction or development from consuming Tartazine. They even tested people at a rate of 1225 mg/kg and still found no adverse effects. So for a 175 pound person that’s 97,443 miligrams! It would be impossible to drink enough Mountain Dew to exceed these levels.

Sperm affects aside, the FDA does recommend that we should only ingest 5 milligrams per kilogram per day of Yellow dye #5. This has nothing to do with reproduction worries, but more about allergic reactions. There is a small percentage of the population that is allergic to Yellow dye number 5 (1/10,000 causes hives according to the FDA). The Center for Science in the Public Interest notes that Tartrazine is found in so many products, from Kraft Macaroni and Cheese and Doritos to shampoos and hand stamps, that the average daily consumption is approximately 12.75mg per day. At these levels, there is still no worries about sperm problems- just allergy ones.

In the end, Mountain Dew will not affect you sperm, testis, or penis size in any way. Should you want to ignore all scientific evidence to the contrary, I suggest you also have your mate stand on her head after copulation. There is no way she could get pregnant then!

If you liked this article and the Bonus Facts below, you might also like:

• Statistically, the Pull and Pray Method Works About as Well as Condoms at Preventing Pregnancy
• The Youngest Person to Give Birth was Just 5 years Old
• The Record for the Most Babies Born to 1 Woman is 69
• What Causes Birth Marks

Bonus Facts:

• According to the World Health Organization, the average ejaculation contains approximately 100 million sperm cells. If you have less than 20 million per milliliter, you are at risk of infertility issues. It only takes one of those little guys to fertilize an egg.
• Unlike women, who stop producing eggs after menopause, a man will be able to produce sperm throughout his life. Although the older he gets, the less sperm he can produce.
• Inside of a woman’s body, a sperm cell can live up to 5 days. Outside of the body, it depends on the conditions. The warmer and wetter the environment, such as a bath or hot tub, the longer it will live. In a dry environment, such as clothing, they die quickly, once the semen has dried.
• Even though Mountain Dew doesn’t affect sperm, temperature does. Optimal sperm production requires specific temperatures. It’s for this reason that when men get too cold, as in the case of swimming in a cold pool (“I just got out of the pool!”) your testes retract back into your body. Conversely, when you get too warm, your body allows them to hang lower via the cremaster muscle. This keeps them cooler. Many studies point to a temperature of between 35-36 degrees Celsius as the optimum sperm production temperature. Your body is normally around 37 degrees C. The warmer your testes, the greater chance your sperm will have damage. So keep the lap-tops off your lap and your heated car seats on low!
• Whether your sperm is good or not, in certain cases, you might want to think twice about donating sperm in Kansas. The state of Kansas has now taken to going after sperm donors for child support. (I can’t make this stuff up!) Mr. William Marotta of Topeka Kansas donated his sperm to a lesbian couple in 2009. Thinking he was doing his due diligence, he and the couple signed an agreement that he would not assume any financial responsibility for any child they mothered.  Fast forward 3 years, and that couple is now separated. One of them lost her job and applied to the state for support. The state then sued Mr. Marotta for back child support- saying that because he did not go through a physician to donate the sperm, there was no proof he wasn’t the mother’s lover. They disregarded the agreement he signed, stating it wasn’t sufficient proof! Sketchy Kansas, sketchy!