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Health Tips

From tips on how to lose weight effectively to ways to combat boredom eating, this collection of informative articles covers a wide range of health topics that matter to real people, like you.

What is Hypothyroidism and Does It Lead to Weight Gain?

If hypothyroidism is left untreated, serious consequences are at risk, including weight changes, heart disease, and other chronic conditions. So if struggling to lose weight or even perhaps gaining it, thyroid function may be at the heart of the cause.


According to the American Thyroid Association, more than 12 percent of the U.S. population will develop a thyroid condition in their lifetime, with up to 60 percent of those not even aware of its presence. So if you are struggling to lose weight or even perhaps gaining it, thyroid function may be at the heart of the cause.

What Is Hypothyroidism?

Before jumping into explaining thyroid and weight gain risks, it is imperative to understand what the thyroid actually is. The thyroid is a small, butterfly-shaped gland in the neck and responsible for producing thyroid hormones that control metabolism. Simply put, metabolism is the total physiological processes in which the body transforms calories from food into usable energy to carry out vital processes, including producing and repairing body cells and circulating oxygenated blood. Ultimately, metabolism is ongoing and continues even when the body is at rest, or more formally known as basal metabolic rate (BMR).

So when it comes to hypothyroidism, the thyroid produces lesser amounts of thyroid hormones. The most common cause of hypothyroidism is properly known as Hashimoto’s disease, or autoimmune thyroiditis, in which the patient’s own immune systems attacks and damages its own thyroid gland. Surgical procedures, radiation, and other illnesses can also compromise the thyroid’s ability to produce thyroid hormones. And despite the cause, when the thyroid hormones are low, metabolism starts to slow down.

Hypothyroidism and Weight Gain

In the case of an underactive thyroid, weight gain is likely related to a compromised basal metabolic rate. In fact, measuring BMR was previously one of the earliest tests to assess thyroid status; people with lower BMRs demonstrated compromised thyroid function. However, BMR is no longer considered a golden standard for diagnosing hypothyroidism, as BMR is complex and can be influenced by age, sex, muscle mass, and other hormones that may be impacted by food intake and energy expenditure. Additional indicators of an underactive thyroid include fatigue, weakness, hair loss, constipation, cold intolerance, muscle cramps, depression, memory loss, and abnormal menstrual cycles in females. Ultimately, the more the severe the case, the more severe the symptoms, which can subside if managed with medication and healthy lifestyle choices, including a nutritious diet and regular physical activity that are described and outlined in greater detail here.

But Can Hyperthyroidism Cause Weight Gain?

Conversely to hypothyroidism, hyperthyroidism causes excess thyroid hormones, subsequently elevating metabolism and increasing the risk of weight loss. If the case is severe and left untreated, significant weight loss can occur and signifies the importance of medication compliance to rebalance metabolism. Ultimately, the condition of hyperthyroidism can still cause weight gain, particularly following a high-calorie diet with limited physical activity. Additionally, the restoration of metabolism following medication can cause the weight loss prior to treatment to be regained. Further signs and symptoms of hyperthyroidism include increased sweating, heat intolerance, muscle weakness, agitation and nervousness, shortness of breath, irregular heart rhythms, shakiness, vision changes.

If any of the noted signs and symptoms of a thyroid condition are apparent, you should schedule an appointment with your primary care provider right away; regular doctor visits can also be a preventative and proactive measure. For more resources and information regarding thyroid conditions, visit the American Thyroid Association’s official webpage here.

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