Smoothie boosters: The jury"s still out

With a reputation of benefiting the body and carrying names like Jamaican Jammer and Peach Sunset, smoothies are hard to resist. Duke students can be seen sipping the fruit-based frothy drinks whether the sunshine beats down on a 70-degree day or a wintry mix creates havoc on the roads.

Part of the success of smoothie sales may stem from the nutritional supplements available for customers. Of the three locations selling smoothies, Alpine Atrium and Trinity Cafe offer a variety of “boosters”—nutritional supplements including immune, energy, fat burner, memory, protein and multivitamin boosters manufactured by MET-Rx.

Alpine Atrium Manager Joseph Holloman and freshman Danna Zabrovsky, a part-time employee at Trinity Cafe, said the Fat Burner/Metabolism booster is the most popular among their customers. The Fat Burner booster is an amino-acid-based supplement that contains tyrosine, taurine and caffeine. Freshens, the company that supplies Alpine Atrium’s smoothie ingredients, markets tyrosine as a “key to mood elevation” and taurine as an amino acid that “plays a vital role in the digestion of fat.”

The protein booster, which builds muscle mass, seems to be particularly popular among male smoothie drinkers and athletes. Senior Kareem Khoury said he sees the effects of the booster and uses it regularly for its benefits. “I gained a lot of weight over the summer on a meat and protein diet,” he said. He adds a protein booster now every time he gets a smoothie, he noted.

Some smoothie drinkers, however, are concerned about potential health effects the boosters may have.

Junior Jacob Stuebs does not add a booster in his Alpine Atrium smoothies. “It takes too long to ask for. [But] honestly, I don’t know if they’re good for me or not,” he said.

Associate Professor of Biochemistry Daniel Gewirth, however, maintains that the amino acids—hydrolyzed from proteins to produce the protein powders—are generally not toxic. The only precaution would be for those with metabolic disorders who are unable to consume the amino acids.

Since most of the ingredients in the boosters are naturally occurring supplements, their effects on the body are dependent on how often they are consumed. The body can take in a fair amount of vitamins above the recommended daily value without suffering from consequences, Gewirth assured. In addition, water-soluble vitamins like Vitamin C are simply excreted from the body when ingested in large quantities, he added.

Nutritionist Greg Hottinger said there is no simple answer to whether booster supplements are beneficial. “It depends on the individual and their diet,” he explained. “Optimal health and a strong immune system is built on real food—not supplements.”

Jack Chao, manager of Wilson Recreation Center’s juice bar Quenchers, said for best results the boosters should be used on a regular basis. Quenchers, which also offers a variety of healthy snacks, makes its smoothies from whole fruits without syrups or food coloring. “The only thing we add is the protein powder, supplement-wise,” Chao said. Hottinger agreed that it would be unnecessary to include boosters when the product is made from whole fruits.

Although the success of smoothies on campus may be attributed to the supposed health benefits, the habit tends to run up a high bill for the daily and regular consumers.

“It works if you stick on it,” sophomore Brandon White said as he ordered an Orange Sunrise with a Multivitamin Booster at Alpine Atrium. “But [the smoothies are] too expensive to have every day.”