Which of the following factors is least likely to contribute to Tina's gastrointestinal symptoms?

A regular sleep pattern is least likely to contribute to Tina’s gastrointestinal symptoms because maintaining consistent sleep helps regulate various physiological processes, including digestion. Adequate sleep supports the overall functioning of the body's systems, including the gastrointestinal tract, promoting effective digestion and reducing stress levels that could exacerbate gastrointestinal issues.

In contrast, high caffeine intake can stimulate gastric acid secretion and increase gastrointestinal motility, potentially leading to symptoms like acid reflux or diarrhea. Spicy foods are well-known triggers for gastrointestinal discomfort in many individuals, as they can irritate the stomach lining and lead to symptoms such as heartburn or indigestion. Irregular meal timing can disrupt the body's natural digestive rhythm, leading to issues like bloating, discomfort, or changes in bowel habits, which contribute to gastrointestinal symptoms.

Thus, while the other options have clear and established links to gastrointestinal discomfort, a regular sleep pattern generally supports digestive health, making it the least likely factor contributing to Tina's symptoms.