The Lesser of Two Evils- Sugar Sweetened vs. Diet Beverages

The age- old question, “What is better, soda or diet soda?” This is a very complex question to answer because on one side we have soda (or other sugar sweetened beverages), which is high in added sugars and low in nutrients, that we know in excess can have negative health outcomes; on the other side we have non-nutritive sweeteners whose health outcomes are poorly understood and potentially harmful when consumed in surplus amounts.

Soda, and other sugar sweetened beverages, are unfortunately a staple in the western diet. We as human beings have an innate taste preference for sweets, because our brains main source of energy is glucose. Soda is LOADED with sugar and as such is a very big source of “empty” calories in the diet. “Empty” calories is a term used in nutrition to describe calories derived from food that contain no nutrients. As such, soda consumption has an association with obesity.

The first problem with soda is that it contributes to 33% of total added sugars consumed in the American Diet. When you consume high amounts of sugars you increase your risk of diabetes by raising your blood glucose and insulin levels, increase triglycerides and low density lipoprotein cholesterol, and lastly you’re more at risk for developing obesity due to the increase in “empty calories” consumed. According to the Dietary Guidelines for Americans, it is recommended to consume less than 10% of your daily calories from added sugars. (1) As such, the American Heart Association recommends no more than 6 teaspoons per day for women and 9 teaspoons per day for men of added sugar. (2) When broken down, one 20oz soda has 2.5 servings and 65 grams of sugar, which equals 13 teaspoons and 260 calories. That is double the daily recommendation for sugar, coming from ONE drink.

The second issue with soda is the fact that you are drinking your calories. As evidenced by DiMeglio, when subjects increased their calories by 18%, or 450 calories, with jelly beans or soda the group who increased calories with jelly beans compensated for this increase in calories by eating less later in the day and did not experience weight gain over a 4 week period. The second group who increased their calories through soda, did not compensate for the caloric increase and ended up gaining weight over the same 4 week period. (3) This data signifies that chewing our food instead of drinking it may promote satiety more effectively and minimize weight gain.

One way consumers avoid these added sugars in soda is to consume diet soda instead. Diet soda has no, or very few, calories and is sweetened with non-nutritive sweeteners such as aspartame, sucralose, and saccharin. Listed below are the mechanisms for these artificial sweeteners and potential adverse health outcomes:

  • Aspartame, also known as Equal, contains 4 calories per gram but little aspartame is needed because it is 200 times sweeter than sugar. Individuals who have the disease Phenylketonuria (PKU) must not consume aspartame because it contains phenylalanine and these individuals cannot metabolize said amino acid. Aspartame has been associated with cancer, diabetes, and ADHD.
  • Saccharin, also known as Sweet’N Low, is 200-700 times sweeter than sugar! This non-nutritive sweetener works because it is heat stable and is not metabolized in the GI tract, therefore it passes through you without ingesting any calories. It is “Generally Recognized as Safe” by the FDA because in lab rats, consumption of saccharin has been associated with cancer but it is believed that the mechanism in rats is not the same for humans. Take that information as you wish…
  • Sucralose, also known as Splenda, is a modified version of sucrose that the body doesn’t recognize, therefore it is poorly digested and is excreted without metabolizing any calories. Sucralose is 600 times sweeter than sugar! Sucralose is found in a variety of products including diet soda, sugar free snack foods, and medicines. Although the FDA has reviewed over 100 studies, there have been no reported adverse health effects found in humans and animals

As with many things in nutrition, the consumption of diet soda and non-nutritive sweeteners has not been widely studied so it is difficult to say with certainty if it is safe or unsafe and “good” or “bad”. The Academy of Nutrition and Dietetics recommends using non-nutritive sweeteners in moderation. (4) IF you are going to drink soda, I would suggest choosing a soda that has been sweetened with cane sugar over diet soda. I only say this because we as scientists understand the metabolism, and potential negative health outcomes to overconsumption of sugar, much better than that of non-nutritive sweeteners.

In a healthy, balanced diet of fruits, vegetables, whole grains, and lean proteins there is room for all foods however “bad” they may be. I don’t think it is appropriate to say you should never ever have a certain food unless there is a legitimate medical reason. If you are an individual who enjoys soda, I would suggest drinking regular over diet, only on special occasions, and not make it a regular occurrence. If you currently drink it regularly, try swapping out the soda for a seltzer or water and slowly ween yourself over time. It might be helpful for you to track your added sugars each day and if you decide you’d like to fill your allotment (6 teaspoons per day for women and 9 teaspoons per day for men) with soda, just know that you should compensate later in the day or risk weight gain, diabetes, and cardiovascular disease! With that said, choosing a water or seltzer is the healthiest option!

Until next week.



  1. Dietary Guidelines for Americans, 2015-2020
  2. American Heart Association, Added Sugars
  3. DiMeglio, DP. Liquid versus solid carbohydrate: effects on food intake and body weight. International Journal of Obesity. 2000. 
  4. Academy of Nutrition and Dietetics, Position Paper, Use of Nutritive and Nonnutritive Sweeteners, 2012

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