Don't Drink Soda

It is clear that the massive soft-drink consumption in our society is a major contributor to health problems. Here are a number of reasons to take soda out of your routine.

Calories from sweetened liquids--whether sodas or fruit juices--don't seem to be perceived by the body as food in the same way that solid calories are perceived as food. Essentially, when you drink the extra 240 calories in a 20-oz. bottle of soda, your body doesn’t treat it as food. (Int J Obesity 2007; 31:1688-1695)

Those who drink the most sugared soda per day have a 67 percent greater chance of contracting type 2 diabetes than those who drink the least sugared soda. Interestingly, when broken down by type of sugar consumed, sodas containing both fructose and glucose combined carried the highest risk of type 2 diabetes. “High-fructose corn syrup” is often the second ingredient, after water, in sugared sodas. (Journal of Nutrition 2007;137:1447-1454)

Drinking more than 2.5 sugar-sweetened drinks per day significantly increases your risk of death from cardiovascular disease. (AJCN 2006; 83:1039-46)

A study in Germany looked at the types of beverages consumed by children between the ages of 9 and 18, and correlated that amount with the change in their Body Mass Index between the two ages. The researchers found that the more sugared soft drinks a child drank--regardless of whether that soft drink was a carbonated soda or a fruit juice--the quicker his Body Mass Index rose as he grew. (Brit J Nutr 2008; 99:1370-1379).

There's not a lot of research into whether drinking calorie-free sodas contributes to weight gain. What we do have, however, is not encouraging for those who drink any type of soda. As part of the San Antonio Heart Study, researchers in Texas followed a group's soft-drink consumption over 8 years. Of the 1,550 people who participated in the study from the beginning, the researchers focused on the 622 who were of normal weight at the outset.

Their data showed that the more soft drinks of any kind a person consumed, the likelier she was to be overweight or obese. For each extra can of soda per day, the risk of obesity increased by 41 percent.

The table below is an easy way to look at their findings. The numbers represent the percentage chance of being overweight or obese depending on the type of soft drink consumed. For instance, 54 percent of those drinking one to two cans per day of diet drinks became overweight during the 8 years of the study.

While I am not a fan of interpreting studies of animals as applying to humans, there was an interesting study at Perdue in which researchers showed that rats fed artificially sweetened juices were more likely to eat more calories when presented with “regular” food. Those researchers feel that the manipulation of sweet tastes reduced the natural ability of the rats to use sweetness to judge the caloric content of the snack they were given.

Keep in mind that humans are not rats (although we do react in similar ways to food). Whether or not drinking more sugar-free sodas impairs the ability of humans to judge other food consumption has not been shown. There are studies, however, that show that people who consume more artificial sweeteners tend to gain more weight.. Also remember that studies like these don’t prove that consuming diet drinks or artificial sweeteners causes weight gain--they simply show that there is a link.

I am not a fan of diet soft drinks and don’t recommend them to my patients. Drink water. We know that tea, green tea and coffee are good for you, and even cocoa is a good choice. While diet sodas do have about the same calories as water, I don’t feel that we have enough information to say that they are as good for you as water.

Timothy S. Harlan, M.D., a.k.a. Dr. Gourmet
Drgourmet.com