A number of factors can limit your weight loss efforts, and these may relate to anything from your diet to your activity level to medications you take. Understanding possible contributory factors to weight gain can help you develop strategies to lose excess weight permanently. However, consult your own doctor for help in losing weight -- particularly if you have health issues -- as each person may require a different approach.
Weight loss typically functions through a calorie deficit. Creating a calorie deficit means that the number of calories you consume every day, week or month is fewer than the number of calories your body uses. According to the BMI Calculator website, 1 lb. of body fat contains approximately 3,500 calories. This means that you need to expend 3,500 calories than you eat in order to lose 1 lb. of weight. A calorie deficit is typically created by increasing the amount of exercise you do -- and therefore the number of calories used -- or by restricting the number of calories you consume.
The closer you are to your ideal weight, the harder it becomes to lose the last few pounds. This is because as your weight decreases, your body's calorie requirements also lessen. You would therefore have to do yet more exercise or restrict calorie intake further in order to create a calorie deficit. Other limitations to weight loss include your age, metabolism, genetic factors and certain medical conditions. According to the University of Maryland Medical Center, or UMMC, Cushing syndrome and hypothyroidism are two medical conditions which can cause obesity. Medical issues which limit physical movement and activity may indirectly contribute to obesity -- if you suffer from osteoarthritis, for example, it may be more difficult to use exercise to create a calorie deficit.
Certain medications may make it more difficult for you to lose weight. The UMMC reports that corticosteroids, antidepressants of the tricyclic group and certain medications for blood pressure can all contribute to weight gain. If you take hormonal birth control, this may also contribute to weight gain and difficulty losing weight. Medical News Today reports that a study published in March 2009 found that women using injectable hormonal birth control each gained 11 lbs. in average over three years. The same study found that such injectable birth control also contributed to a 3.4 percent average increase in body fat composition over the same time period.
Although it is tempting to lose weight as quickly as possible, crash dieting is believed to be ineffective as a long-term weight loss method and can lead to muscle loss rather than fat loss. You're more likely to sustain a healthy weight loss of approximately 1 to 2 lbs. per week over time, the Centers for Disease Control and Prevention advises. This would represent a deficit of 7,000 calories over the course of a week.
Always consult your own doctor before making any significant lifestyle or dietary changes. Unexpected weight gain or extreme difficulty losing weight may indicate an underlying physical or psychological problem requiring medical monitoring and diagnosis. Also, do not attempt to create a calorie deficit greater than 500 to 1,000 calories daily. Your daily calorie requirements will depend on your weight, age, activity level and gender. According to the American College of Sports Medicine, it is considered unsafe for any female to restrict daily calorie intake below 1,200. For a male the minimum safe level is 1,800 calories.