The Effects of Diet Sodas

by Michele Turcotte, MS, RD

Diet sodas are sugar-free and provide few, if any, calories. Individuals trying to lose weight or consume less sugar often choose diet sodas. Some enjoy the flavor of these beverages, preferring them over plain water. Diet drinks, however, particularly diet sodas, are nutrient-free and may be associated with health risks. They contain poorly tested or unsafe non-nutritive sweeteners; and, because they are highly acidic, may have the potential to erode tooth enamel.


Diet sodas are devoid of nutrients, particularly vitamins and minerals. While calorie-free, they offer no health benefits. Although 100 percent fruit juices are high in sugar, they are also usually rich in vitamin C, an essential nutrient for human health. Vegetable juices are low in calories and sugar and rich in nutrients, such as vitamin A, C and folate; a 6-oz. serving counts as a serving of vegetables. Milk, fortified with vitamins A and D, is also very nutritious. Skim milk is low in fat and rich in calcium, potassium, riboflavin and protein, and is a source of energizing carbohydrates. Drinking diet sodas may displace other, more nutritious beverages in the diet.

Erodes Tooth Enamel

Many individuals think that it is the sugar in sodas that damages teeth, while others believe the carbonation is to blame for adverse oral health effects. The high acidity level of these drinks, or their low pH value, actually does the most harm. According to the Top News website, diet sodas contain phosphoric and citric acids. When these acids make contact with your teeth, they can erode the protective barrier or enamel. Water has a neutral pH level of 7. Enamel erosion occurs when teeth are consistenly exposed to acidic liquids--those with a pH value of less than 5.5, according the Family Gentle Dental Care website. Diet 7-Up, Diet Dr. Pepper and Diet Coke all have pH values of 3.39 to 3.67--making them highly acidic. Diet sodas have an acidity level closer to that of battery acid, which is 1.0, than to that of water.

Risk of Diabetes

According to findings of a study published in Diabetes Care in April 2009--after adjusting for lifestyle, demographic and dietary factors--daily consumption of diet soda was associated with a 36 percent greater risk of developing metabolic syndrome, a pre-diabetic condition. Furthermore, those who drank at least one diet soda daily were found to have a 67 percent greater relative risk of type 2 diabetes compared with those who did not consume any diet sodas. It is important to note, however, that observational studies cannot establish a cause-and-effect relationship.

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About the Author

Michele Turcotte is a registered, licensed dietitian, and a certified personal trainer with the National Academy of Sports Medicine. She has more than 12 years of experience in clinical and corporate settings, and has extensive experience in one-on-one diet counseling and meal planning. She has written freelance food and nutrition articles for Trouve Publishing Inc. since 2004.