Add a 330ml can of Diet Coke to your order. Sparkling Low Calorie Soft Drink with Vegetable Extracts with Sweeteners. Love it light? Add some sparkle to your day, minus the calories with Diet Coke. Diet Coke is a sugar free, low calorie soft drink. No Sugar. No Calories. Gluten-free, dairy-free and nut-free. Contains vegetables extracts and sweeteners.