Make it a daily habit to eat healthfully and exercise to slim down in three weeks. Changing how your body functions on the inside will make you look slimmer on the outside. Healthy foods supply the energy necessary to burn calories. As long as you burn more calories than you consume, the weight will start to fall off.
Choose healthy foods instead of junk food, high-calorie, sugary, salty and fatty foods. Opt for choices such as whole grains, fruits, vegetables, low-fat dairy products and lean meats. Throw away any unhealthy foods and stop buying fast food. Many people overeat because unhealthy food is available and accessible, not because of hunger, according to Dr. Phil McGraw, author of "The Ultimate Weight Solution." Overeating any type of food can cause weight gain.
Be physically active as much as possible throughout the day. The more active you are, the more calories you will burn. Choose activities you enjoy to make it easier to exercise. For example, full-court basketball or cross-country skiing can burn more than 800 calories per hour, depending on your body weight, according to Health Status Internet Assessments. Be active several times a day. Run in the morning, play a sport during the afternoon and go hiking before dinner. According to the American College of Sports Medicine, 20 to 90 minutes of activity on most days of the week is recommended for weight loss.
Burn 3,500 calories more than you consume daily to lose 1 pound per week. For example, cut 200 calories per day and burn 300 calories with physical activity. A larger caloric deficit will cause more weight loss and quickly make you slim. However, losing weight too fast is difficult to maintain, and the weight is often regained just as quickly. Small deficits lead to long-term weight loss, according to the American College of Sports Medicine.
Incorporate two to three days of resistance training into your weight-loss plan. People with muscles burn more calories per day, even at rest. Use weight training, calisthenics, resistance tubing or any type of activity that causes overload to your muscles, according to "Fitness: Theory and Practice."
Find ways to add activity into your daily routine. For example, park your car farther from the mall to increase your walking distance. Hand-wash your car instead of going to the car wash. Take the stairs instead of the elevator and stand whenever possible instead of sitting. Every bit of activity will burn more calories throughout the day, causing more weight loss.