Going on a diet means foregoing sugary drinks and greasy foods to lose weight. We believe we're making health-conscious choices by opting for "diet" food labels, but there may be more than meets the eye. Diet soda was created to help us drop the pounds, but some evidence suggests it can tip the scale — not in our favor.

In Brit Lab's latest video, "Can Diet Drinks Make You Fat?" host Gabriel Weston conducts a blood sugar test to determine whether there's a difference in blood sugar before and after drinking a standard sugary coke and a diet coke on an empty stomach. First, Weston and her colleague Ben measured their baseline blood sugar level, then they tried some of the drinks, and then did a blood sugar reading again 20 minutes after sipping a drink. Weston's blood sugar reading went from 4.2 to 4.4 after drinking diet soda, while Ben's spiked from 4.6 to 6.5 after drinking regular soda.

The test shows artificial sweeteners, like aspartame, work in the sense they keep blood sugar low, but why does science suggest they contribute to weight gain?

Weston explains there are several theories circulating on the effects of artificial sweeteners on weight. In animal studies, giving mice small quantities over a couple of weeks leads to a small, but statistically significant, increase in body weight gain. Scientists theorize this may be because the body associates sweetness with calorie intake, so when we eat something sweet, the body prepares for an increase in calories. However, when those calories don't come, the body gets confused, which can lead to a slower metabolism, or craving more food to offset this effect.

Currently, there is no conclusive proof diet drinks make us gain weight. Scientific data has measured correlation more than causation, meaning soda isn't directly leading to weight gain. It could be people may begin drinking diet soda when they're starting to gain weight.

If diet soda is a guilty pleasure from time to time, chances are it won't wreak havoc on our waistline. But, if it's a daily comfort, this could lead to long-term health consequences, like obesity, and type 2 diabetes.

Diet soda isn't healthy, but it isn't proven to kill us — yet.