Coffee, black
Black coffee contributes very few calories, but caffeine and coffee acidity can matter when nausea, reflux, diarrhea, or low appetite are active. Tolerance is highly individual, so the yellow rating is intentionally conditional.
Why it received this rating
The concern is not sugar or fat because plain black coffee contains little of either. The rating reflects caffeine and acidity, plus the fact that a strong cup can replace food or fluids when appetite is already low.
Nutrition snapshot
Per serving: 1 cup (8 fl oz)
Source: USDA FoodData Central, FDC 171890, Beverages, coffee, brewed, prepared with tap water. The displayed serving uses 1 cup (8 fl oz); very small nutrient values are rounded for display. Source reviewed August 17, 2026. Review nutrition source How nutrition data is handled
Portion and preparation guidance
Start with about 8 to 12 ounces and consider drinking it with or after a small meal instead of on an empty stomach. Decaf or half-caf is an easy comparison if caffeine seems to be the problem.
Symptoms or considerations
If coffee repeatedly worsens heartburn, nausea, loose stool, jitteriness, or appetite suppression, reduce the amount, switch to decaf, or pause it during symptom flares.
Common questions
Can I keep drinking coffee while taking a GLP-1 medication?
There is no universal rule that coffee must be avoided. Compare your own response to a smaller cup, decaf, or coffee taken with food, and reduce it if it consistently worsens symptoms.
Individual tolerance varies. This rating is general educational guidance, not a statement that this food is the right choice for your personal medical needs. Follow advice from your prescriber or registered dietitian.
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