Skip to content

Number of Diet Coke cans you should drink a day before it becomes ‘dangerous’

The calorie-free or low-calorie label is oddly appealing and our minds obsessed with easy yet effective weight loss techniques would see nothing wrong with the supposedly “safer” soda.

The low-calorie count of your favorite sugary drink shouldn’t be the sole reason to indulge in it excessively. A licensed dietician warns of the adverse effects of drinking “too much” Diet Coke.

Ice cubes in soda
Credit: Jonathan Knowles | Getty Images

Dietician’s take on ‘how much Diet Coke is too much?’

Let’s look at the nutrient facts for a 12-ounce can of Diet Coke. It has 0 calories, 0 grams of fat, carbohydrate, sugars, or protein; contains 40 milligrams of sodium and 46 milligrams of caffeine.

If you, like many, think that the lack of calories is a good enough reason not to monitor your consumption of sugary drinks, a dietician offers more insight into its “unpleasant side effects”.

Registered dietician Abbey Sharp explains in one of her TikTok videos that “Diet Coke in moderation is very unlikely to cause any harm.” However, substituting it for your regular water daily just because it has no calories can negatively impact your health.

She draws attention to aspartame – an artificial sweetener added to Diet Coke – which isn’t necessarily the “safest” choice when consumed excessively. If you’re wondering “How much Diet Coke is too much?”, Abbey has the answer.

“For a 150-pound adult, you could get into potentially higher-risk territory if you were drinking more than 9 to 14 cans per day,” she says.

@abbeyskitchen

Is there such thing as TOO MUCH diet coke?? This is a great example of why calorie free doesn’t mean you can go ham. #dietcoke #crispydietcoke #dietcokeforlife #aspartame #dietitiansoftiktok #debunked

♬ original sound – Abbey Sharp

The other side effects

Caffeine is the other active ingredient in the soda beverage that can cause more side effects in adults who do not monitor their drinking habits.

The FDA recommended sodium for an average healthy human is 400 milligrams a day – equivalent to neary 9 cans of Diet Coke.

“If you had eight cans a day and no other sources of caffeine, you hit that max. If you drink coffee as well or eat a lot of chocolate, you’re going to get there a lot faster,” she adds.

Adults who are sensitive to caffeine can feel the “unpleasant side” effects of excess Diet Coke more strongly than others. As for the nutrition in Coke Zero, it has 34mg of caffeine and uses potassium citrate (instead of the citric acid used in Diet Coke.

To understand which of the two beverages is “healthier”, The Focus spoke to Avery Zenker, who has a masters degree in nutrition and contributes to EverFlex Fitness.

He said: “Neither beverage is healthier. If health considerations are important to you when it comes to hydration, soda isnt the best choice.

Abbey Sharp is a Registered Dietitian (RD), a top food writer and blogger, a TV and radio personality, and a YouTuber with millions of followers on social media. She holds a B.A.Sc. in Nutrition Science from Ryerson University alongside Dietic certification from Sunnybrook Health Sciences Centre.