Is it safe to drink diet soda daily for someone watching their heart?

What's actually in it

Diet sodas use aspartame, sucralose, acesulfame-K, or saccharin instead of sugar. They replace the glucose spike with different biological effects: gut microbiome shifts, glucose intolerance in some people, and as new research shows, measurable artery effects over time. A daily diet soda across years is the exposure pattern in these studies.

Heart patients often switch from regular soda to diet soda on the logic that sugar is the problem. The substitution keeps the habit without fixing the cardiovascular risk.

What the research says

A 2026 study in Naunyn Schmiedebergs Arch Pharmacol found that long-term artificial sweetener exposure increases the risk of atherosclerosis. The mechanism involved endothelial dysfunction, inflammation, and gut-derived metabolites that stress the artery wall. At daily-user intake levels, the effect was measurable.

Sparkling water with a squeeze of citrus replaces most of what diet soda delivers (carbonation, bright flavor, zero calories). Unsweetened iced tea or hibiscus tea covers the bitter-sweet note some people miss. For a treat, a small glass of real fruit juice diluted 1:3 with sparkling water has about a quarter of the sugar of regular soda, none of the artificial sweeteners, and tastes good.