What causes internal heat?

2. Excessive consumption of spicy and hot food, such as pepper, onion, leek, etc., can deplete yin fluid, resulting in deficiency of viscera, resulting in yin deficiency and internal heat. 3. Innate lack of innate endowment leads to yin fluid deficiency, resulting in imbalance of yin and yang, unable to balance yang, and yin deficiency and internal heat.