The thyroid is a butterfly-shaped gland in the front of the neck. It produces hormones that control the speed of your metabolism

Relationship between thyroid and body weight

Thyroid disease and body weight

In the previous blog we saw the symptoms and types of thyroid disease. Now lets see the Relationship between thyroid and body weight

weight loss after thyroid
Thyroid awareness

[cro_accordionstart] [cro_accordionitem title=”What is the Relationship between thyroid and body weight” item=”active” ]There is a complex Relationship between thyroid and body weight and metabolism. Thyroid hormone regulates metabolism in both animals and humans. Metabolism is determined by measuring the amount of oxygen used by the body over a specific amount of time. If the measurement is made at rest, it is known as the basal metabolic rate (BMR). Indeed, measurement of the BMR was one of the earliest tests used to assess a patient’s thyroid status. Patients whose thyroid glands were not working were found to have low BMRs, and those with overactive thyroid glands had high BMRs. Later studies linked these observations with measurements of thyroid hormone levels and showed that low thyroid hormone levels were associated with low BMRs and high thyroid hormone levels were associated with BMRs.[/cro_accordionitem]



[cro_accordionend] [cro_callout text=”Relationship between hyperthyroidism and weight.” layout=”1″ color=”1″]Since the BMR in patients with hyperthyroidism is elevated, many patients with an overactive thyroid indeed experience some weight loss. Furthermore, the likelihood of weight loss occurring is related to the severity of the overactive thyroid. Thus, if the thyroid is extremely overactive, the individual’s BMR increases which leads to increased caloric requirements to maintain that weight. If the person does not increase the calories consumed to match the excess calories burned, then weight loss will ensue. As indicated earlier, the factors that control our appetite, metabolism, and activity are very complex and thyroid hormone is only one factor in this complex system. Nevertheless, on average the more severe the hyperthyroidism, the greater the weight loss observed. Weight loss is also observed in other conditions where thyroid hormones are elevated, such as in the toxic phase of thyroiditis and also if one is on too high dose of thyroid hormone pills. Since hyperthyroidism also increases appetite, some patients may not lose weight, and some may actually gain weight, depending on how much they increase their caloric intake.



[cro_callout text=”Relationship between hypothyroidism and weight gain” layout=”1″ color=”1″]Since the BMR in the patient with hypothyroidism is decreased, an underactive thyroid is generally associated with some weight gain. The weight gain is often greater in those individuals with more severe hypothyroidism. However, the decrease in BMR due to hypothyroidism is usually much less dramatic than the marked increase seen in hyperthyroidism, leading to more modest alterations in weight due to the underactive thyroid. The cause of the weight gain in hypothyroid individuals is also complex, and not always related to excess fat accumulation. Most of the extra weight gained in hypothyroid individuals is due to excess accumulation of salt and water. Massive weight gain is rarely associated with hypothyroidism. In general, 5-10 pounds of body weight may be attributable to the thyroid, depending on the severity of the hypothyroidism. Finally, if weight gain is the only symptom of hypothyroidism that is present, it is less likely that the weight gain is solely due to the thyroid.


[cro_callout text=”Frequently asked questions by thyroid patient” layout=”1″ color=”1″]   [cro_callout text=”Why do I gain weight when hyperthyroidism is treated?” layout=”2″ color=”1″] Because the hyperthyroidism is an abnormal state, we can predict that any weight loss caused by the abnormal state would not be maintained when the abnormal state is reversed. This is indeed what we find. On the average, any weight lost during the hyperthyroid state is regained when the hyperthyroidism is treated. One consequence of this observation is that the use of thyroid hormone to treat obesity is not very useful. Once thyroid hormone treatment is stopped, any weight that is lost while on treatment will be regained after treatment is discontinued.



[cro_callout text=”How much weight can I expect to lose once the hypothyroidism is treated?” layout=”3″ color=”1″] Since much of the weight gain in hypothyroidism is accumulation in salt and water, when the hypothyroidism is treated one can expect a small (usually less than 10% of body weight) weight loss. As hypothyroidism usually develops over a long period of time, it is fairly common to find that there is no significant weight loss after successful treatment of hypothyroidism. Again, if all of the other symptoms of hypothyroidism, with the exception of weight gain, are resolved with treatment with thyroid hormone, it is less likely that the weight gain is solely due to the thyroid. Once hypothyroidism has been treated and thyroid hormone levels have returned to the normal range of thyroid hormone, the ability to gain or lose weight is the same as in individuals who do not have thyroid problems.



[cro_callout text=”Is hypothyroidism a life long disorder?” layout=”2″ color=”1″] In majority of cases, hypothyroidism is indeed lifelong. It may be temporary in a few conditions (eg., ingestion of certain drugs or pregnancy).



[cro_callout text=”Does the diet have to be changed?” layout=”3″ color=”1″] Diet need not be changed. On the other hand, if you are suffering from some other diseases like diabetes or high blood pressure, appropriate modification of diet may be needed kindly consult your doctor / qualified dietician for this purpose.



[cro_callout text=”Can hypothyroid patients lead a normal married life?” layout=”2″ color=”1″] Hypothyroid patients who are properly treated can lead a normal sex life. Hypothyroid women in particular who are properly treated can have regular menstrual cycles, normal conception, pregnancy and delivery. There is no excessive risk of defects in newborn. The offspring of a hypothyroid individual need not necessarily have thyroid disorder.



[cro_callout text=”What happens if a hypothyroid patient becomes pregnant? ” layout=”3″ color=”1″] The dose of thyroxine has to be adjusted during the period of pregnancy. Many patients may need an increasing dose. However the dosage adjustment should only be done by your doctor. As soon as you miss a menstrual cycle get the pregnancy confirmed and contact your doctor as early as possible.



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By  Ruchi Shah

About Ruchi Shah

Ruchi Shah has completed Bachelor’s in Biochemistry and currently pursuing Masters in Sports Nutrition. She is working on a Research project on Creatine Supplementation. She is working as a Research Nutritionist at k11 Fitness Academy. She has worked on major projects like Aqua aerobics, Effect of Phytochemicals on Exercise Performance and Workplace Exercises. She advises clients and their families on nutritional principles ,diet modifications, food selection and preparation and much more. She provides tips on healthy eating habits for prevention and treatment of illnesses. She follows the Diet Mantra “Diets, like clothes, should be tailored to you”. Nutrition Specialist Ruchi Shah