Biolog 1: Diet Sodas--Don't be fooled

We've all been there before--too calorie conscious to purchase that bottle of coke, so we opt for its diet counterpart, or its coke zero brother if you're feeling adventurous. But really, how do we know if it's sticking true to its "diet" label?

According to the American Diabetes Association, these innocent, sweet beverages are doing more harm than good. The "no calorie" tag has its price--and a large one, literally. The School of Medicine of the University of Texas Health Science Center in San Antonio reports in one study that diet soda drinkers saw a 70% increase in their waistlines. After adjusting for age, height, weight, and other contributing factors during this 9.5 year study, researchers found an disturbing pattern: Those who drank two or more diet sodas a day saw a 500% increase in waistline growth greater than non-drinkers.

500%. The US economy could use a 500% growth increase right about now.

While it isn't clear how diet soda could contribute a [jelly] role to weight gain, earlier works have constructed a "if it looks and quacks like a duck" theory. As a race, humans have evolved to utilize glucose as our main source of energy. Glucose is found in countless foods--when consumed, the body will either use the simple sugar immediately as energy (ATP), or store it as fat. The presence of glucose preps the brain to expect a heavy calorie meal.

Aspartame, the synthetic sugar in diet beverages, serves as a glucose agonist. When the body ingests aspartame, it triggers the same response we have to glucose. The body is deprived of the expected calories, so naturally cravings and hunger pangs flood your mind. This effect was also seen in mice, where a high-fat, aspartame supplemented diet led to increased glucose fasting levels.

We're not 100% sure whether the effects on the mice are translatable to humans, and the researchers did not clarify how much asparatme they added to the mice diet. The lobbyists and diet soda groupies will sing for more details and more repeated trials before this battle is long over--in the meantime, I'll remind you of the only lesson I learned in biochemistry: "Everything in moderation." Finally, invest in one of these bad boys and love thy H2O.

Life is short and sweet, but making it too sweet will only make it shorter.



Biolog is a weekly series that brings to light the controversial, disturbing, fascinating, and thought-provoking topics of molecular and evolutionary biology. Written by biologist Gabe Guzman.