A Juicy Secret

A Best Seller Touts the Weight Loss Power of Grapefruit Juice and Caffeine

Should Starbucks sell grapefruit juice? If you’ve read Tim Ferriss’ New York Times Best Seller “The 4-Hour BODY” you might recall his mention of grapefruit juice and its effect on caffeine. While Ferriss himself is not generally in favor of much fruit or fruit juice in his diet, he does mention the benefit (or detractor, depending on your viewpoint) of a certain flavanoid found in grapefruits which extends the fat burning properties of caffeine.


Indeed, naringin, the flavanoid that gives grapefruit its bitter flavor, is also thought to slow the breakdown of certain drugs, including caffeine, in the intestines—a double-edged sword depending on what other chemicals you may be ingesting. However, if you are one of the millions (if not billions) of people worldwide that willingly seeks that pick-me-up each morning compliments of a double shot latte, you might have a friend in grapefruit.

Ferriss himself may call for a scant intake of fruit—due to high amounts of sugar—but grapefruit juice has far less sugar than most other juices and a ton of health benefits.  Such examples include:


-Vitamin C to help to support the immune system


-Limonoids that inhibit tumor formation by promoting the formation of glutathione-S-transferase, a detoxifying enzyme

-Lowers cholesterol

-Prevents kidney stones

-Protects against colon cancer

-Boosts liver enzymes that clear out carcinogens


Burning fat while conquering your TPS reports spells efficiency. Just make sure the brand you buy says “100% Grapefruit Juice” and not just “100% Juice.” Tropicana, for example, sells “100% Ruby Red Grapefruit Juice” in the standard half-gallon carton, yet their 10 ounce plastic bottle size—advertised as 100 percent juice—is in fact a mixture of white grape juice and other juices with higher amounts of sugar. It’s 100 percent juice but only 13 percent grapefruit juice. If you want a smaller size to go with your sandwich, opt for Tropicana’s white grapefruit juice (even lower in sugar than the ruby red) or organic brands like Odwalla.


Caution:  While grapefruit juice has a ton of health benefits, it can be dangerous for those taking prescription drugs—for the same reasons that it extends your caffeine buzz. Grapefruit juice inhibits a specific enzyme (p450) in the liver. As a result, medications which are also metabolized by this enzyme may accumulate to toxic levels in the body.