Ensuring adequate intake of fat-soluble vitamins can be achieved through a balanced diet that includes a variety of foods. For example, vitamin A can be found in foods like carrots, sweet potatoes, and spinach. Vitamin D is obtained from exposure to sunlight and foods like fatty fish and fortified milk. Nuts, seeds, and vegetable oils are good sources of vitamin E, while leafy greens like kale and spinach are rich in vitamin K.