Mountain Dew affects men the same way any high-sugar, highly acidic soda does, with a few specific wrinkles worth knowing about. A single 20-ounce bottle contains 77 grams of sugar and enough citric acid to sit at a pH of 3.22, making it both a metabolic and dental concern for regular drinkers. The persistent internet rumor that it lowers sperm count through Yellow 5 dye is largely overblown, but the sugar itself may actually pose a real hormonal risk that most men don’t know about.
The Sperm Count Rumor vs. Reality
The most popular claim about Mountain Dew and men is that Yellow 5 (tartrazine), the dye that gives it its signature color, kills sperm or lowers sperm count. This myth has circulated since at least the 1990s, and it’s not entirely baseless, but it’s misleading.
Animal research has shown that tartrazine, when combined with other synthetic dyes and given to rats at high doses, can cause testicular inflammation and damage to the cells that produce testosterone. In one study published in JBRA Assisted Reproduction, rats given 20 mg/kg of dye mixtures showed degeneration of Leydig cells (the cells responsible for making testosterone) and an increase in immature sperm. At lower doses, though, the tissue looked largely normal. The concentrations used in these studies are far higher than what you’d get from drinking Mountain Dew. You would need to consume an absurd volume daily to approach those doses. So while the dye isn’t biologically inert, the amount in a bottle of Mountain Dew is not a realistic fertility threat on its own.
Sugar, Insulin, and Testosterone
The real hormonal concern from Mountain Dew isn’t the dye. It’s the sugar. A 20-ounce bottle delivers 77 grams of sugar, more than double the 36-gram daily limit the American Heart Association recommends for men. That sugar comes primarily as high-fructose corn syrup, which drives up blood glucose rapidly and contributes to insulin resistance over time.
A study of U.S. men aged 20 to 39, published in PubMed Central, found that those who consumed the most sugar-sweetened beverages had 2.3 times the odds of having low testosterone compared to the lightest drinkers. Even in the short term, drinking a glucose load causes a measurable drop in both total and free testosterone. The likely pathway is straightforward: excess sugar leads to weight gain and insulin resistance, both of which suppress testosterone production. In that same study, men with a BMI of 25 or higher had 3.7 times the risk of low testosterone compared to men at a healthy weight.
This isn’t unique to Mountain Dew, but the sheer sugar density makes it an efficient way to push yourself into that risk zone. Two bottles a day puts you at 154 grams of added sugar, more than four times what’s recommended.
Belly Fat and Metabolic Risk
Regular soda consumption doesn’t just add weight evenly. It preferentially increases visceral fat, the deep abdominal fat that wraps around your organs and drives metabolic disease. A cross-sectional analysis of over 2,500 adults from the Framingham Heart Study found that daily soda drinkers had 10% more visceral fat and a 15% higher ratio of visceral to subcutaneous fat compared to people who didn’t drink soda at all. Daily consumers also had higher rates of abnormal cholesterol levels.
The mechanism appears to involve fructose specifically. High fructose intake promotes fat accumulation in the liver, which triggers insulin resistance throughout the body. Fructose may also directly activate fat storage in visceral tissue by stimulating stress hormone receptors, which are more concentrated in belly fat than in fat elsewhere on the body. For men, this visceral fat accumulation feeds back into the testosterone problem: more belly fat means more of an enzyme that converts testosterone to estrogen, creating a cycle that’s hard to reverse without significant dietary changes.
Tooth Enamel Takes a Hit
Mountain Dew is one of the more acidic sodas you can buy, though not the most acidic. Regular Mountain Dew has a pH of 3.22, which falls squarely in the “erosive” category. For reference, tooth enamel begins dissolving below a pH of 4.0, and every single unit drop below that threshold causes a tenfold increase in enamel breakdown. Mountain Dew Voltage is worse at 3.05, bordering on the “extremely erosive” category (below 3.0).
Interestingly, colas like Coca-Cola (pH 2.37) and Pepsi (pH 2.39) are actually more acidic than Mountain Dew. But Mountain Dew’s combination of acidity, high sugar content, and the way many people sip it slowly throughout the day creates prolonged acid exposure that keeps your mouth in the erosion zone for hours. Dentists in Appalachia coined the term “Mountain Dew mouth” to describe the severe decay they see in patients who drink it regularly, often multiple bottles a day.
Caffeine Is Moderate, Not Extreme
Mountain Dew has a reputation as a high-caffeine soda, but it’s actually only slightly above average. An 8-ounce serving of a caffeinated citrus soda contains about 36 mg of caffeine, compared to 33 mg in a typical cola. A full 20-ounce bottle works out to roughly 91 mg. That’s less than a standard cup of brewed coffee at 96 mg per 8 ounces. The safe limit for most adults is around 400 mg per day, so caffeine is not the primary concern here unless you’re drinking four or five bottles daily.
Brominated Vegetable Oil Is Gone
For years, Mountain Dew contained brominated vegetable oil (BVO), an emulsifier that kept the citrus flavoring evenly distributed. BVO accumulated in fatty tissue and was linked to potential thyroid and neurological effects. PepsiCo removed it from Mountain Dew before the FDA formally banned it, but the regulatory picture is now settled: in July 2024, the FDA revoked its approval for BVO in food entirely, concluding it was no longer considered safe. Companies had until August 2025 to clear existing inventory. If you’re drinking Mountain Dew purchased recently, it no longer contains BVO.
What Regular Consumption Looks Like
A single Mountain Dew on occasion is not going to tank your testosterone or rot your teeth. The concern is with the pattern that Mountain Dew tends to encourage: one or two 20-ounce bottles a day, sipped over hours, often as a caffeine source or habit. At that level, you’re looking at 154 grams of sugar daily from soda alone, continuous acid exposure to your teeth, a measurably increased risk of low testosterone, and a shift toward visceral fat storage that compounds over months and years.
The effects aren’t unique to Mountain Dew. Any high-sugar soda consumed at similar volumes would produce similar results. But Mountain Dew’s combination of extreme sugar content, erosive acidity, and cultural status as an all-day drink makes it one of the more efficient vehicles for these problems. The men most at risk are those who drink it habitually and in volume, not those who grab one at a barbecue.