Pizza can be considered unhealthy if it is consumed in excess and on a regular basis. Here are some reasons why pizza may not be the healthiest food choice:

1. High in calories: One slice of pizza can contain anywhere from 200-300 calories, depending on the toppings and crust. If you eat multiple slices, the calorie count can quickly add up.
2. High in fat: Many types of pizza are high in fat, especially if they are made with fatty meats like pepperoni or sausage, or if they are loaded with cheese.
3. High in sodium: Pizza can be high in sodium, which can contribute to high blood pressure and other health issues.
4. Low in nutrients: While pizza can provide some nutrients, such as protein and carbohydrates, it is typically low in essential vitamins and minerals.
5. Processed ingredients: Many store-bought or fast food pizzas are made with processed ingredients, such as preservatives, artificial flavors, and additives, which can be harmful to your health if consumed in excess.

While pizza can be a tasty and convenient food choice, it is important to enjoy it in moderation and balance it out with a variety of healthy foods as part of a well-rounded diet. There are also healthier options available, such as pizzas made with whole grain crusts and topped with vegetables.