Thyroid cancer is a serious condition that can have a variety of symptoms, including weight gain. An excess of T3 and T4 hormones can cause hyperactivity and weight loss, while a lack of these hormones can lead to sluggishness and weight gain. Calcitonin helps regulate blood calcium levels, and if the thyroid produces too much of these hormones, you can lose weight unexpectedly. Weight gain is usually associated with hypothyroidism, a condition where the thyroid produces too little of these hormones.
This can lead to an unexplained weight change, which is one of the most common signs of a thyroid disorder. The decrease in basal metabolic rate (BMR) due to hypothyroidism is usually much less dramatic than the marked increase seen in hyperthyroidism, leading to more modest alterations in weight. Most weight gain in hypothyroid individuals is due to excessive salt and water accumulation. Massive weight gain is rarely associated with hypothyroidism, but 5-10 pounds of body weight can be attributed to the thyroid depending on the severity of the hypothyroidism.
If weight gain is the only symptom present, it is less likely to be due solely to the thyroid. Unlike hyperthyroidism and hypothyroidism, thyroid cancer doesn't cause symptoms such as weight changes, heart palpitations, and thinning hair. Patients or doctors may be able to feel or see changes in the size and shape of the thyroid gland. If left undiagnosed, medullary thyroid cancer can spread to other tissues in the neck and eventually reach the liver, lungs, bones, and brain. High basal metabolic rate (BMR) induced by drugs such as amphetamines can lead to negative energy balance and weight loss.
Ultrasound may be suggested if there are two or more people in your immediate family who have been diagnosed with thyroid cancer. Thyroid hormones help the body use energy, stay warm, and keep organs functioning properly. Thyroid cancer is a known risk factor for several types of cancer including breast cancer, endometrial cancer, colon cancer, adenocarcinoma of the esophagus, prostate cancer, liver cell carcinoma, leukemia, non-Hodgkin lymphoma, and melanoma. Treatment for hyperthyroidism may include medication antithyroid which reduces hormone production by the thyroid. Differences between hyperthyroidism and hypothyroidism are important as they affect the severity of the cancer and type of treatment needed. Body Fat Distribution, Adulthood Weight Change, and Thyroid Cancer Risk in the NIH-AARP Diet and Health Study show that BMR measurement was one of the first tests used to assess a patient's thyroid status.
Medical guidelines from the American Association of Clinical Endocrinologists (AACE), Associazione Medici Endocrinologi (AME), and European Thyroid Association for Clinical Practice (ETACP) for Diagnosis and Treatment of Thyroid Nodules are also available. A goiter or lump in the thyroid is a common symptom of thyroid cancer but more than 90 percent of all thyroid goiters are benign and could be related to another condition such as hypothyroidism or iodine deficiency. Other causes of hypothyroidism include temporary inflammation of the thyroid or medications that affect thyroid function.