Though not all marshmallows are toxic to dogs, they certainly arent good for your dog. Made from sugar, corn syrup, gelatin, and vanilla extract, and coated with either cornstarch or...
Never feed chocolate-covered marshmallows to dogs. Chocolate contains theobromine and caffeine, both toxic to dogs and potentially fatal in sufficient quantities.

Furthermore, visual representations like the one above help us fully grasp the concept of Dogs Eating Chocolate-Covered Marshmallows.
The short answer: Regular marshmallows are not recommended for dogs, and sugar-free marshmallows can be extremely dangerous. These ingredients arent toxic but offer no nutritional benefits and can cause health issues over time.

Chocolate, which is commonly paired with marshmallows in desserts, is toxic to dogs and can cause vomiting, diarrhea, elevated heart rate, tremors, and seizures.

Furthermore, visual representations like the one above help us fully grasp the concept of Dogs Eating Chocolate-Covered Marshmallows.
If a dog consumes sugar-free marshmallows or shows neurological signs such as shaking or seizures, seek emergency veterinary care immediately. Left untreated, xylitol exposure can lead to rapid liver failure and may be fatal.