How a Zero Calorie Soda Can Give You Diabetes

Updated July 2026

It makes no sense at first. Doesn't sugar cause diabetes? And isn't diet soda sugar-free? It is — and yet it can still push you toward diabetes. Here's how.

How can a zero-calorie soda give you diabetes?

Through your gut hormones, not calories. Artificial sweeteners blunt GLP-1, the hormone that limits the rise in blood sugar after a meal. With GLP-1 suppressed, blood sugar climbs higher after you eat, and doing that day after day means you need more insulin to be produced, eventually exhausting your pancreas and moving you toward diabetes. It's that GLP-1 suppression that explains why diet-soda drinkers develop type 2 diabetes at the same rate as regular-soda drinkers.

Does diet soda cause heart disease and stroke?

The evidence increasingly points that way. In a study of more than 80,000 women through the Women's Health Initiative, the American Heart Association reported that high diet-drink intake — two or more a day — was linked to significantly higher risks of stroke, heart disease, and death from any cause. The stroke risk was especially pronounced in women with no prior heart disease or diabetes, and in those with a BMI over 30.

Can diet soda really cause tooth decay?

Yes. All soda, diet and regular, is highly acidic, coming in at a pH of around 3. To put this in perspective, a neutral pH is 7, the value for water. Meanwhile, tooth enamel begins to demineralize when the mouth's pH falls below 5.5. Weaken your tooth enamel, and invite problems – with or without sugar.

If diet soda were a drug, would it be allowed on the market?

Probably not. If a prescription drug raised the risk of preterm delivery, it would carry a stern warning against use in pregnancy. If it raised the odds of depression by about 30%, that would be a labeled side effect. And if daily use raised the risk of type 2 diabetes by 67%, it would never clear the FDA. Diet soda has been associated with all three.

Does diet soda at least help you lose weight?

No — and it may do the opposite. Which makes sense given the impact on natural GLP-1 production. Long-term data link non-nutritive sweeteners to increases in weight, waist size, and BMI, along with higher rates of high blood pressure, metabolic syndrome, and cardiovascular disease. The WHO reached the same conclusion in 2023, advising against non-sugar sweeteners for weight control. The "guilt-free" swap doesn't deliver.

What should you drink instead?

Water — the original zero-calorie drink. If plain water feels boring, make it interesting: add a slice of lemon, orange, or lime; cucumber; mint; or add a few pineapple spears to a pitcher. Far more refreshing, safe for our teeth, and already in tune with our biology.

Most of us would say that a couple of cans of soda a day doesn't sound like much, but over a year that's 60 cases of soda. That means even eliminating one can a day represents a huge improvement – leaving 30 cases of soda behind at the store saves not only money – but also your health. So, quit the habit, lean on foods and drinks that raise GLP-1 naturally. Your heart and brain will thank you.

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