Is There Bull Sperm in Your Energy Drink?

Popular Lore Says There's an Unsavory Secret Ingredient in Energy Drinks

Red Bull Energy Drink
George Pimentel/WireImage/Getty Images

According to online rumors, Red Bull, Monster, Rockstar and other brand-name energy drinks contain a secret ingredient to pep you up: bull semen. As it happens, there is an ingredient in most energy drinks called taurine. But is it really made using an extract from bull testicles?


  • Description: Internet rumor
  • Circulating since: 2001
  • Status: False

Example of the Energy Drink - Bull Semen Rumors

As shared on Facebook, April 1, 2014:

Did You Know Your Energy Drinks Contain BULL URINE & SEMEN

Energy Drinks Contain Ingredient Extracted From Bull Urine And Semen. A study done by Longhorn Cattle Company, tested some of the top energy drink brands such as Red Bull, monster etc. What they found might leave your stomach in a knot. They found that the drinks do, in fact, contain bull semen.

Analysis of the Bull Sperm in Energy Drinks Rumor

Despite longstanding rumors to the effect that top-selling energy drinks such as Red Bull, Rockstar, and Monster contain unlisted ingredients such as bull sperm, bull urine and/or testosterone extracted from bull testicles, there is no truth to any of these claims.

Where did people get this notion? It was apparently inspired by the fact that all of these beverages do contain taurine, which name was derived from taurus, which is Latin for bull.

Scientists chose that name because, even though taurine occurs naturally in all fish and animal tissues (including human tissues), the first time they managed to isolate the amino acid it was from a specimen of ox bile.

Ox bile isn't bull semen, it's produced by the gall bladder. But it's still an unpleasant-sounding substance. If that's still worrisome to anyone, rest easy.

The taurine used in Red Bull and other energy drinks is completely synthetic. It's not made from animal tissues of any kind. It is an ingredient suitable for vegans.

Why Do Energy Drinks Have Taurine?

Why do they put taurine in energy drinks? To make good on the name "energy drink." Some studies have suggested that taurine may improve athletic performance and can even, combined with caffeine (another ingredient found in these products), improve mental acuity. Please note the use of the words "may" and "can" in the previous sentence. Further research needs to be done to confirm that taurine provides these specific health benefits.

According to the Mayo Clinic, up to 3,000 mg. of supplemental taurine per day is considered safe for human consumption. Energy drinks typically contain around 1,000 mg. per serving (one 8.4-ounce can, in the case of Red Bull).

Some doctors warn that energy drinks should be consumed in moderation, but that's mainly due to their high caffeine content, not because there's any danger of a bull semen overdose.

Sources and Further Reading:

Is Taurine Made from Bull's Testicles? Red Bull - Frequently Asked Questions

Taurine and Health Verywell

Energy Drinks - Benefits and Risks Verywell

Liquid Cocaine: How Hype and Urban Legend Made Red Bull into a Commercial Cocktail Juggernaut Slate, 2 February 2001