Mushrooms like button mushrooms (aka cremini or white mushrooms) are naturally low in fat and sugar but surprisingly high in plant-based protein—great for maintaining muscle mass and keeping you feeling full. With just 22 calories per 100 g (about 1 cup sliced), they’re the ultimate low-calorie meat substitute and work beautifully in salads, stir-fries, or stuffed dishes. Bonus: mushrooms grown under sunlight are also a rare plant source of vitamin D, which supports fat metabolism and boosts your immune system.