The main functions of dietary fats include providing a concentrated source of energy, supporting cell structure, and assisting in the absorption of fat-soluble vitamins like A, D, E, and K. Fats are essential for hormone production and play a critical role in maintaining healthy skin, hair, and brain function. Additionally, different types of fats, such as saturated, unsaturated, and trans fats, have different impacts on health. While unsaturated fats are beneficial for heart health, excessive intake of saturated and trans fats can lead to various health issues, highlighting the importance of balancing fat consumption.