Final answer:
Monitoring food portions, matching energy consumed with energy expended, and establishing a healthy pattern of eating and physical activity are key to maintaining a healthy weight.
Step-by-step explanation:
The key to maintaining a healthy weight involves monitoring food portions and ensuring that the energy consumed from foods matches the energy expended through body functions and activity. If more calories are consumed than burned, excess energy can lead to weight gain, while burning more calories than consumed can lead to weight loss. It is recommended to adhere to a low-calorie, low-fat diet, engage in regular physical activity, eat breakfast every day, limit television time, weigh oneself regularly, and establish a healthy pattern of eating and physical activity for long-term weight management.