Dr K Spinal Care Today Headshot


I know some of you have had your suspicions all along. As you sip on your diet soda after stepping on the scale to be greeted with bad news, you may have already been thinking, “I don’t think my diet is working.”

Well, you’re right. It isn’t.  Amazingly, recent studies have indicated that people who habitually drink diet sodas are statistically more likely to gain weight than people who routinely drink regular sugary sodas.

How could this possibly be true?  The regular soda drinkers are consuming a boatload of fructose and other sugars, laden with non-nutritious calories. Meanwhile, the diet soda drinkers are trying to be the good ones, consuming only a few calories with their “light” drinks. It just isn’t fair. How do diet sodas really cause weight gain?

The actual drink does not add the pounds. It is the behavior of the drinkers that causes the weight gain.  The weight gain effect varies from one person to another. There are those few skinny folks out there who routinely prefer diet sodas to avoid the sugary versions, so obviously this weight gain effect does not affect everyone equally.

The problem arises in the actual eating behavior of the diet soda drinker. There are primarily two effects that work to sabotage the intentions of the dieter.   First, the act of ordering a diet soda tends to create an internal dialogue that rationalizes consuming whatever else that may be appealing to the dieter. This can lead to over consumption of more junk food or extra calories. (“I’ll have the double burger, large fries, apple pie, ice cream and a diet Coke.”)

The second effect is related to the physiological response of our bodies to sweet tastes. We are wired to associate sweet tastes with ingesting high calorie foods. When we drink a sweet tasting soda, our bodies are expecting a load of calories to digest. Artificial sweeteners can be 50 to 200 times sweeter than sugar.  

When we drink a diet soda, we taste the sweet flavor and our bodies start revving up for the calorie load. When the body is fooled by tasting an artificially sweetened food, a craving for high calorie food can result. Therefore, in susceptible people, the artificially sweetened drink actually amplifies the craving of high-calorie foods.

The research is not complete on the physiology and behavioral responses to artificial sweeteners and these effects vary from person to person.  You may not be affected in the ways described above. 

However, if you have been wondering why you can’t seem to lose weight even though you have switched to drinking diet sodas, it may be time to switch to drinking water. Dieting is generally not a successful way to lose weight anyway, so investigating alternative approaches might prove more effective.

There are a few more health concerns about diet sodas other than the possibility of actually gaining weight. Several popular sweeteners were ultimately pulled from the market because of cancer risk.  Many researchers still have concerns about how our bodies respond to artificial sweeteners.

Teen girls drinking diet sodas are increasing their risk of osteoporosis later in life significantly. The ingredients in diet sodas lead to decreased bone density. Research has also shown that many teens who routinely drink diet sodas rarely drink milk, further adding to their risk for bone density problems such as fractures.

Teen females are not the only ones at risk. One study found that male and female adults that consume three or more cola type sodas (diet or regular) per day had on average 4 percent lower scores on bone density tests.

One of the main culprits in these drinks is phosphoric acid, or phosphate. Phosphates interfere with calcium absorption in the body. So even if you are taking calcium supplements it may not work. Caffeine also has a negative effect on calcium absorption.

So, the bottom line is that drinking diet sodas to lose weight may backfire. Additionally, the ingredients in all sodas can have significant negative consequences if consumed too often.

Dr. Mark Kestner is a licensed chiropractic physician in Murfreesboro. His office is at 1435 NW Broad St. Contact him at mkestner@DrKestner.com

Recommended for you