“The skin of kiwi fruits contain cholesterol-lowering fiber, some good news: If you remove the skin off your cucumbers, you're peeling away. 11 Healthy Fruit & Vegetable Treats for Your Dog or Cat Celery; Zucchini; Green bell peppers; Cucumber; Broccoli; Blueberries; Watermelon. The question 'Is cucumber a fruit or a vegetable?' is a common one. At Tommies, we chiefly look at the answer to this question from a health perspective. Fruit.