Updated March 13, 2015.

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

If you've already checked out the 8 factors that affect your caloric intake, then it's time to evaluate your daily calorie output. The total number of calories you burn each day is flexible and relatively easy to change. 

17 Reasons That Your Diet Didn't Work (continued)

Did any of the first 8 reasons sounds familiar? If not, don't worry. Here are 9 more reasons that your diet may have failed you.

• Workouts that are too hard  Believe it or not, but your workout might be the reason that you're not losing weight.  Some programs like CrossFit could actually be harmful to your weight loss program if it causes you to take too much time off or worse, causes injury.  Try to get some physical activity every day.  That means you should schedule easy and moderate workouts along with the high intensity fat burners.
   

• Non-exercise activity level.  If your fat-burning Tabata workout exhausts you to the point that you spend the rest of the day on the couch, then you are not benefiting from NEAT.  Non-exercise activity thermogenesis can account for up to 2000 calories burned per day.  Make sure you keep moving all day long. Take the stairs, carry your own groceries, stand while you chat on the phone.  It all adds up. 
   
• Stress-induced laziness.  Some people react to stress by moving.  But others take to the couch in times of trouble.  If you are going through a difficult time, give yourself permission to rest.  But try to incorporate easy workouts with a friend to gain support and stay active. 
   
• Fatigue. The simple act of dieting can cause stress and fatigue. Even if your weight loss program is not at fault, daily exhaustion is likely to hinder your workouts and your NEAT.  Learn how to sleep better for weight loss. Take simple steps like charging your phone in the kitchen or changing the lighting in your bedroom to get a better night's sleep.
   

• Physical factors.  Medical conditions, like thyroid disease, can affect your daily caloric expenditure.  Factors such as age and genetics also play a role in the number of calories you burn.  Talk to your doctor about factors that affect your metabolism. Sometimes there are things you can do to give it a boost. 
   
• Body composition.  Muscle burns more calories than fat.  To increase your calorie burn all day, boost your lean muscle mass.  Eat enough protein to fuel your weekends and build strong muscle. Then complete regular strength training workouts at home or at the gym to get lean and buff.
   
• Your job. Occupations that require you to sit at a desk will decrease your daily energy output. You're not likely to change jobs to lose weight, but you may be able to make simple changes in your office to increase your daily caloric burn.  Stand while you type, skip the elevator and walk the stairs, turn sit-down meetings into walking meetings.  Some companies are even installing treadmill desks to help workers increase their daily activity level and improve health.
   
• Exercise habits.  The way you schedule your workouts can make a difference in the number of calories you burn during each one.  For example, if you schedule a long run on a day after a tough bootcamp workout, you may be too tired during the run to gain a real benefit.  Create a balanced exercise program to burn calories with consistent but reasonable workouts.
   
• Exercise-induced binge eating.  Believe it or not, one of the most common mistakes that dieters make is eating too much and justifying the episode with exercise.  In fact, it is not uncommon for new marathon runners to gain weight for this reason.  Make sure you are properly fueled for your workouts so that you don't binge when you're done.

Is My Diet Doomed to Fail?

Trying to find the reason your diet isn't working can be a pain.  But if one of these factors is contributing to your weight loss woes, you need to address it if you want to slim down.  Get creative and try different tweaks. And don't forget to reach out to friends and family and connect with me for support and motivation.