Weight loss is the holy grail of most diet and exercise programs. You could also spend a lifetime counting the number of supplements out there which purport to help shed pounds. Still, very few people are successful over the long run in achieving and maintaining a healthy weight. In this article, I will discuss 5 reasons why people cannot lose weight.
It is important to understand that weight loss can be different from fat loss. Ideally, all weight that is lost on a “weight loss plan” is fat, but many fad diets use carbohydrate restriction to force a dramatic water weight loss (with a very real risk of lean tissue loss as well), which, while making the scale move impressively, does little to change the way you look or how your clothes fit.
Five pounds of fat loss will change your appearance much more substantially then five or ten pounds of water loss. Similarly, especially when someone first starts exercising, he or she will build muscle while losing fat, so in the beginning of a training program, other measurements (body fat, waist circumference) are much better indicators of progress than the scale. However, building lean tissue is a much slower process than losing fat, so if your goal is fat loss, the scale can be a very useful measurement, especially if you are not new to weight training. If the scale is not moving and your clothes are not fitting better, it is worthwhile to look at the following.
Why You Can’t Lose Weight #1: Excess Calorie Intake
In order to lose weight, you must eat fewer calories than you burn. Dietary recall can be very inaccurate. In one study, men and women underestimated their calories by 11% and 13% respectively.1 Additionally, many people under estimate portion sizes and have trouble figuring out how many calories are in foods they did not make. And while online tracking applications have made it easier than ever before to log food intake, no existing program is perfect. For example, I looked up a particular protein bar on Myfitnesspal and found 3 entries that understated the calories by as much as 40%. If you are not careful when logging, you may end up gaining weight even with the best intentions.
Why You Can’t Lose Weight #2: Metabolic Issue
Underactive thyroid, for example, may be much more common than previously thought. There is great disagreement among medical professionals as to the best way to diagnose and treat hypothyroidism.2 Hormonal imbalances, especially in women, can predispose to weight gain. For example, extra estrogen in relation to progesterone can contribute to weight gain. High levels of the stress hormone cortisol can cause weight gain indirectly by increasing appetite.
Recommendation: Have your hormone levels checked if you think this may be an issue, but understand that weight loss requires eating fewer calories than you burn regardless of your hormonal status.3
Why You Can’t Lose Weight #3: Medications
There are a number of medications that can cause weight gain. Antihistamines like Benadryl can cause significant weight gain (The American Society of Bariatric Physicians estimated up to 10 pounds per year), as can antidepressants and certain blood pressure medications, among others.
Recommendation: If you are having trouble losing weight, go over your medication list with your doctor and look for alternative medication if something you’re on is associated with weight gain.
Why You Can’t Lose Weight #4: Relying Only On Exercise
Our bodies are very efficient, and simple math breaks down when it comes to calories burned versus consumed. There are metabolic and behavioral adaptations that vary significantly from person to person and are not accounted for using simple equations. For example, John goes out and walks a mile. He estimates a burn of 100 calories, so he treats himself to a 100-calorie piece of chocolate. It’s a wash, right? Not so fast. You see, if John had just sat there instead of walking, he still would have burned some calories. Thus, the net burn is less than 100 calories, so if he did that consistently, he would gain weight. To make this even more complicated, research I’ve seen has shown that people who exercise tend to subconsciously move less during the rest of the day, partially offsetting the calories burned during exercise.
Recommendation: Manipulate calories to control the rate of weight loss. Do not try to factor in exercise, the goal of which should be progression. Only if you are losing weight too fast (I.e. over 2-3 pounds per week), adjust your calories upward.
Why You Can’t Lose Weight #5: Metabolic Defect
Prolonged periods of severe calorie reduction can significantly slow metabolism. A common scenario is a person goes on a 600 calorie-per-day diet and loses weight rapidly. However, soon weight loss will slow considerably and may even stop, as his body recognizes the lack of food and goes into a conservation mode. In order to continue losing, this person must further reduce calories, which will be very detrimental to long-term results. Usually, this is followed with rapid rebound weight gain with the same slow metabolism. Now he is worse off than when he started. To fix this, he may need to go through a prolonged period of fixing his deranged metabolism before he can even think about losing again.
Recommendation: Take it slow and do not reduce calories drastically. If you do plateau, assess your intake. If there is room to safely decrease your calories, then do so. Or, if you already are very low, make a short-term goal to increase metabolism. This requires meticulous food logging and involves very slowly adding food (i.e. 5-10 grams of carbs per week or two) with the goal of maintaining your current weight. Then, when maintenance needs are higher, a reduction will get you losing again.
Losing fat can be complicated, but if you’re dedicated to staying lean and in shape, it is definitely something that you can take on successfully.
- Jonnalagadaa S, Mitchell D, Smiciklas-Wright H, Meaker K, Van Heel N, Karmally W, Erhsow A, Kris-Etherton P. Accuracy of energy intake data estimated by a mutiplepass, 24 hour dietary recall technique. American DieticAssociation Jour. Mar 2003. V 100;3.303-311. ↩
- A significant number of practitioners (me included) believe TSH testing is inferior to examining free thyroid hormone levels (specifically the ratio of T3 to reverse T3). Treatment choices from low thyroid include the active thyroid hormone precursor T4 (Synthroid, Levothyroxine), active T3 (Cytomel, compounded sustained release T3) or combination pills (Armour). Again, this is a very controversial area and treatment should be guided by a knowledgeable health care professional. ↩
- The metabolic component is important to discuss, but it shouldn’t be the first thought. People should have this evaluated by their primary doctor after demonstrating a failure of a disciplined approach to diet and exercise. Plus, being overweight or obese is not the only manifestation of hypothyroidism. ↩