How much weight would you gain from the sundae?

The amount of weight you would gain from consuming a sundae depends on various factors, including the sundae's calorie content, your overall diet, and your activity level. Generally, weight gain occurs when you consume more calories than you burn. A typical sundae can range from 300 to over 1,000 calories, so if it significantly exceeds your daily caloric needs, it could contribute to weight gain over time. However, a single sundae won't lead to immediate weight gain, as weight changes are influenced by long-term dietary patterns.