My friend had her thyroid removed due to cancer. She said she can't lose weight because she has no thyroid. Is this right? She very badly needs to lose about 75 pounds. She also has arthritis all over. She is taking a lot of pills to relieve the pain.

Judy

Oooh boy, is that ever a cop-out! (I'm showing my age. Do people still say "cop-out"?)

Yes, the thyroid gland plays a crucial role in regulating weight. Patients with hypothyroidism (a condition in which the thyroid gland does not produce sufficient thyroid hormone) gain weight -- in fact, that's one of the primary symptoms of hypothyroidism. If her thyroid gland has been removed, your friend has no endogenous (internal) source of thyroid hormone.

Thyroid hormone has many effects on the human body; one of its most important roles is in regulating the basal metabolic rate (BMR), the rate at which our bodies expend calories while at rest. If you have a high BMR, you will "burn calories off" at a greater rate than an imaginary friend (call him Toby) with a low BMR. If you and Toby weigh the same and eat an identical diet, your weights will diverge. For example, if this diet is very fattening, Toby will tend to gain more than you will. On a restricted calorie diet, you will lose weight faster than Toby.

So, in a very limited sense, your friend is right. No thyroid gland, no thyroid hormone, right? Wrong! She must be taking thyroid hormone replacement medication. (If not, she will eventually die from the lack of this hormone.) Finding the appropriate dose of medication can be tricky, so her doctor may have to check her thyroid hormone level frequently (via a simple blood test) in order to tinker with her dosage. If she is not taking enough medication, she could be hypothyroid, and this would certainly make weight loss challenging. Nevertheless, this is a solvable problem.
Once her thyroid hormone level has stabilized within the range of normal, she can no longer blame her obesity on her lack of a thyroid gland. Genetics is, arguably, the most important factor in determining the presence or absence of obesity. Habits are certainly important, too. "Eat less, exercise more" has always been good advice for weight loss. Two other key points:

1. The patient must make a permanent change in his/her habits (with respect to diet and exercise).
   
2. Weight loss should be gradual.
   

Crash diets fail because it impossible for most humans to maintain such a radical alteration in their dietary habits. Rapid weight loss is treacherous for a number of reasons -- one can lose muscle mass (which is definitely counterproductive!) and one's body can "go into starvation mode," in which the body clings to calories.
Your friend should first find out from her doctor if her thyroid hormone level is normal. If there is any doubt, then she needs to be tested. Once she determines that her level is normal, she should NOT buy the latest diet book ... she should consult with a licensed dietician. Such professionals are trained to assess a patient's caloric and nutritional requirements, and can then recommend a safe and effective diet. Finally, she should talk to her physician about exercise. (Due to her arthritis, there may be limitations to her activities.)