McDonald's US Diet Coke (Medium): calories, ingredients and allergens

Nutrition information: McDonald's US Diet Coke (Medium)

Nutrition figures are McDonald’s USA published data, per item as sold and before any optional sauces or extras. Boone converts them to the portion and age comparisons on this page.

McDonald's US Diet Coke (Medium) is one of the lightest choices on the menu

McDonald's US Diet Coke (Medium) contains 0 calories, no added sugar and 15mg of sodium.

FDA Daily Values (2,000-calorie diet)

Processing and additives: McDonald's US Diet Coke (Medium)

McDonald's US Diet Coke (Medium) is a single manufactured product. Reading the ingredient list closely, it contains flavourings, colours, preservatives, emulsifying and buffering salts and non-nutritive sweeteners. These are not there to add nutritional value. They make industrial production and distribution possible.

Boone classifies McDonald's US Diet Coke (Medium) as NOVA group 4, ultra-processed, based on the additives named above. NOVA groups foods by how far they are from their whole-food form, not by how nutritious they are. A group 4 food is not automatically unhealthy, and a group 1 food is not automatically healthy. Read from the published ingredient list, September 2026.

Ingredient count by order: McDonald's US Diet Coke (Medium)

The 9 manufactured ingredients

aspartame, caffeine, caramel color, citric acid, natural flavor, phosphoric acid, potassium benzoate, potassium citrate, sodium saccharin.

The 1 raw ingredients

carbonated water.

What those ingredients are, by type

Boone counts every distinct named ingredient on McDonald’s published component lists, including sub-ingredients, and removes duplicates, so salt appearing in four components counts once. Additive class names are dropped and the named substance kept, so “leavening (baking soda)” counts baking soda once. Ice and water added at the counter are not counted. Raw covers whole foods and basic kitchen staples such as flour, sugar, salt and oil. Manufactured covers substances that only exist as an output of industrial processing. Every figure here is a minimum. The build uses a Sweet ’n Sour sauce.

Ingredients by component: McDonald's US Diet Coke (Medium)

Ingredients taken from the McDonald’s USA product pages, retrieved September 2026, with obvious spelling errors corrected. Recipes change - always check in restaurant before ordering if you have an allergy.

Allergen information: McDonald's US Diet Coke (Medium)

Contains aspartame, a source of phenylalanine, which matters for people with phenylketonuria (PKU). Contains non-nutritive sweeteners, which UK rules would require to be flagged as “with sweeteners”. Contains caffeine, but McDonald’s USA does not publish a figure. Contains = declared by McDonald’s USA. May contain = McDonald’s states the allergen may be present. McDonald’s prepares food in shared kitchens, so no item can be guaranteed allergen free. UK rules also require barley, oats, mustard, celery and sulphites to be declared; these are shown where the ingredient list names them. Retrieved September 2026.