Is diet soda better for you than regular soda?

At some point in your life, you’ve probably been asked, Coke or Pepsi? Most people lean strongly one way or the other, with just a few falling in the middle. What about diet or regular? With increased awareness of caloric intake throughout the United States, individuals have turned to focus their attention on their liquid calories. Is skipping the extra calories helpful or hurtful?
What’s the difference between diet and regular soda?
Regular soda is generally a mixture of carbonated water and sweeteners, like high fructose corn syrup or sucrose; phosphoric acid, if it’s a dark cola; “natural flavors;” and caffeine. 
Diet soda will contain similar ingredients to its regular counterparts, with the primary exception being that they contain sugar substitutes. Common sugar substitutes used in diet soda include aspartame, acesulfame potassium, sucralose and stevia. Most sugar substitutes are considered “non-nutritive,” meaning they offer little to no energy when consumed.
Reduced-calorie soda is sort of an in-between option, which typically uses a combination of sucrose and a sugar substitute (commonly stevia), in an effort to save on calories from regular sweeteners. 
What are the benefits of drinking diet soda?
Most health care practitioners wouldn’t automatically recommend drinking diet sodas. However, if an individual consumes regular soda on a consistent basis, and isn’t ready to or willing to quit altogether, there can be some benefits to consuming diet soda as opposed to regular. 
  • Calorie reduction – It can assist with promotion of weight loss
  • Decreasing the amount of sugar in your diet -- One 12-ounce can of regular soda contains 10 to 11 teaspoons of sugar. The American Heart Association recommends no more than six and a half teaspoons from added sugar for women and 10 teaspoons for men per day. 
  • Improved blood sugar control -- One 12-ounce can of regular soda typically contains 40 to 50 grams of carbohydrates, which is within the recommended carbohydrate intake range for an entire meal when consuming an 1,800-calorie diet. 
What are some risks with drinking diet soda?
There are many purported health risks associated with sugar substitutes, most of which originate from rumors and internet scare. For instance, aspartame, one of the most common sugar substitutes, has been heavily scrutinized for its supposed involvement with causing health issues ranging from migraines to cancer. 
However, while the debate over the safety of aspartame will likely continue, what we do know about this particular sugar substitute is that is has been thoroughly researched since its approval for use in soft drinks by the FDA. It lacks conclusive evidence of posing any health risks, unless you have a metabolic disorder in which you can’t appropriately metabolize the amino acid phenylalanine. 
Although evidence supports the safety of sugar substitutes used in diet soda, there are still some considerations to keep in mind when consuming diet soda on a consistent basis:
  • Diet sodas contain little to no calories and offer essentially no benefit from a nutritional standpoint - the concern here is with the potential of missing out on opportunities to consume something else, such as low-fat milk (source of calcium) or unsweetened green tea (source of micronutrients which may offer anti-inflammatory benefits). 
  • Perception that drinking diet soda will enable more indulgent choices - some individuals who drink diet soda seem to be under the impression the calories saved enables them to order higher-calorie menu items, which may lead to an overconsumption of calories; this can stall weight loss and lead to weight gain. 
  • Weight and nutrition issues in children - kids who drink diet soda could be at risk for becoming underweight from filling up on these non-caloric drinks and missing out on key nutrients for growth and development they would otherwise receive from drinking dairy and other sources of calcium and protein. 
Which soda should you choose to drink?
The choice between regular or diet soda depends on several factors: taste preference, frequency of consumption, current body weight, dietary habits and intakes of other sugar-containing foods. Regardless of which you choose, just remember that weight loss and/or maintaining a healthy weight comes down to calories. If you consume more calories than your body needs, you’ll eventually gain weight, whether they come from regular soda or by combining poor choices when using diet soda to “save calories.” 
If you’re looking to decrease or eliminate soda intake, but still crave something “bubbly,” try flavored carbonated waters. Other alternatives include trendy products, such as lower-sugar varieties of Kombucha, a fermented tea which contain high quantities of probiotics, or watermelon water, labeled as “WTR MLN WTR,” which contains potassium and citrulline, both of which are beneficial for replenishing after workouts. 
Matthew Black is a registered dietitian at The Ohio State University Wexner Medical Center.