Hi there and thanks for asking us on HCM. No, I do not think you have a rare medical condition. With regard to the thyroid, I have practiced medicine for years and now, after studying evidence based hormonal replacement medicine and applying it to patients, I have come to realize that most people are hypothyroid until proven otherwise. If you have some or all of the following - difficulty losing weight despite dietary restriction and exercise, wake up tired in the morning after sufficient sleep, have cold hands and feet, are cold intolerant, have dry skin, some level of constipation, poor appetite, lethargic, dysthymic - you may be hypothyroid. Hypothyroidism is not determined by a number on a blood report - the patient s symptoms play a big role. Blood tests are just one way of measuring thyroxine levels in the blood. Many women have cells that are thyroxine -resistant i.e. they are not sensitive enough to allow thyroxine (T3) into their cells to bring about energy production and increase the metabolic rate. Up to date, there is no simple test to measure the activity of T3 (the active form of tyroxine at the cellular level). There are also women who have antibodies against thyroxine, making it difficult to reach effective levels within cells to bring about change. Then there are those who produce reverse T3 - an inactive form of thyroxine. You can test for this, it is expensive though. Thus, if you truly want to feel a change and lose weight, your free T3 levels need to be in the upper limit e.g. range given (3.3 - 6.5) your levels ought to be at least 6.0. There is evidence that supplementing with NATURAL thyroid like desiccated thyroid has enabled many women to attain better energy levels and as a side effect, weight loss. The other thing to consider is insulin resistance - insulin is also an important hormone in the body with regard to weight loss. In a nutshell, the more insulin you have, the harder the weight loss. In those who are overweight, the body has to produce more insulin to cope with its insulin-resistant cells. Eating clean and exercising daily should decrease insulin resistance, but if there is underlying hypothyroidism, this becomes an uphill task. The levels that matter are not the serum insulin levels obtained at fasting, but the levels obtained 2 hours after eating a meal. Generally, overweight people are insulin-resistant. Insulin resistance can be fixed by metformin (widely available drug) but has to be prescribed by a doctor and your liver and kidney function need to be monitored. The other option which may be available over the counter is to go on a chromium compound to reduce insulin resistance. I hope this information helps you. Take care Dr Shabnam