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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?

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, an estimated 20 million Americans have some form of thyroid disease. More than 12 percent of the U.S. population will develop a thyroid condition during their lifetime.

There are two primary types of thyroid disease, including hypothyroidism and hyperthyroidism. Weight changes are those most well-known indicators of a thyroid disease. But undiagnosed thyroid disease increases the risk of certain serious conditions, such as cardiovascular diseases, osteoporosis and infertility. It can also be life-threatening.

This is worrisome, as up to 60 percent of those with thyroid disease are unaware of their condition. However, knowing the characteristics of thyroid disease can prompt early detection and initiate proper treatment.

What Is Hypothyroidism?

Before identifying hypothyroidism, it is important to have a basic understanding of the thyroid and its significance.

The thyroid is a small, butterfly-shaped gland in the neck. It is responsible for producing thyroid hormones that control metabolism and regulate body processes.

Simply put, metabolism is the total physiological processes in which the body transforms calories from food into usable energy. This energy is required to carry out vital processes, including producing and repairing body cells and circulating oxygenated blood.

Metabolism is ongoing and continues even when the body is at rest. This is more formally known as basal metabolic rate (BMR).

Basal Metabolic Rate

Basal metabolic rate is the rate of energy expenditure of a person at rest. It eliminates the variable effect of physical activity and accounts for 60 percent of total daily expenditure.

BMR can be determined with a simple equation: 24 X body weight in kilograms (kg). To calculate the total daily energy expenditure, multiply the BMR by an activity factor. (I.e. 1.3 for sedentary, 1.5 for moderately active, and 1.7 for extremely active)

Take, for example, a 200 pound (200/2.2 = 91 kg) person who is moderately active:

BMR = 24 X 91 kg = 2184 calories per day X 1.5 activity factor 
Total energy expenditure = 3,276 calories per day

Based on these calculations, one would need to consume about 3,200 to 3,300 calories to sustain current weight. Under most conditions, consistently consuming under this calorie mark leads to weight loss. Eating more leads weight gain.

However, metabolism is complex and can be influenced by age, sex, and muscle mass. BMR also can be impacted by a number of factors, including diseases that impact the thyroid. This is because thyroid hormones regulate the rate of cellular metabolism.

Specific to hypothyroidism, also known as underactive thyroid disease, the thyroid gland does not produce sufficient thyroid hormones. This can slow down metabolism.

The most common cause of hypothyroidism is properly known as Hashimoto's disease. Also known as autoimmune thyroiditis, Hashimoto’s disease is an autoimmune disease. The body's immune system attacks and damages its own thyroid gland, thus compromising thyroid hormone production.

Surgical procedures, radiation, and other illnesses can also compromise the thyroid's ability to produce thyroid hormones. But despite the cause, metabolism starts to slow down when thyroid hormone is low.

A slowed metabolism can lead to the following signs and symptoms of low thyroid function:

• Fatigue
• Weakness
• Hair loss
• Constipation
• Cold intolerance
• Muscle cramps
• Depression
• Memory loss
• Abnormal menstrual cycles in females
• Weight gain

Hypothyroidism and Weight Gain

Again, hypothyroidism is when the thyroid gland produces lesser amounts of thyroid hormones. When the thyroid hormones are low, metabolism starts to slow down.

In the case of an underactive thyroid, weight gain generally follows due to a compromised BMR. Unless dealing with a severe case, though, an average of five to 10 pounds is gained.

Ultimately, the more the severe the case, the more severe the symptoms. This is also the case in hyperthyroidism, though it often comes with a different set of signs and symptoms.

Does Hyperthyroidism Cause Weight Gain?

Conversely to hypothyroidism, hyperthyroidism causes excess thyroid hormones, subsequently elevating metabolism and increasing the risk of weight loss. Losing weight particularly occurs when individuals do not eat enough calories to match their metabolism.

However, each case is different, and some with hyperthyroidism might experience weight gain. This is mostly due to an increased appetite, another symptom of hyperthyroidism. And especially if consuming a high-calorie diet with limited physical activity, weight gain is likely.

Individuals with hyperthyroidism may also experience:

• Increased sweating
• Heat intolerance
• Muscle weakness
• Agitation and nervousness
• Shortness of breath
• Irregular heart rhythms
• Shakiness
• Vision changes

Weight Management and the Thyroid

Managing weight mostly depends on the type of thyroid disease. However, there are common denominators between the two in regards to weight management and overall health.

Medication to Control Thyroid
First and foremost, a diagnosis and prescribed synthetic thyroid hormone can help restore compromised metabolism caused by either hypo- or hyperthyroidism. An improved metabolism from medical treatment can help those gain and lose weight.

For instance, the restoration of metabolism following medication can also cause the weight loss prior to treatment to be regained.

Diet & Exercise
Sticking to a healthful diet naturally reduces caloric intake when metabolism is slowed down. Even with hyperthyroidism, a nutrient-dense diet can lower inflammation in the body that often occurs.

Reduce the intake of highly processed and refined products that can trigger inflammation. Focus on whole foods and incorporate more of the following:

• Whole grains, choosing whole grains over refined grains at least 50 percent of the time

• Fruits and veggies, particularly choosing fresh varieties rather than those purchased with added sugar, salt, and other preservatives

• Lean proteins and plant-based proteins, which may include poultry, eggs, and legumes

• Milk and dairy products, in which low-fat varieties can further control calorie and saturated fat intake

• Healthy fat sources, particularly those rich in unsaturated fatty acids such as olive oil and fatty fish

In addition to a balanced diet, individuals can also benefit from regular physical activity. The American Heart Association recommends 150 minutes of moderate to intense exercise weekly. Jogging, cycling, dancing, and swimming are forms of cardio exercises that increase heart rate.

Strength training two to three times per week helps facilitate muscle strengthening and building. An increased muscle mass helps increase BMR, or resting metabolism.

Additional Considerations
Ultimately, seek out the care of a practitioner if experiencing any signs and symptoms of a thyroid disease. A healthcare professional will assess and discuss safe methods that may work best for you. This may include thyroid medications and lifestyle changes.

Also continue coordinating care, which may include from a primary care doctor, endocrinologist, and dietitian. They will provide careful monitoring to measure the effectiveness of treatment and reevaluate as needed.

Thyroid and Weight. American Thyroid Association.

Written By Sarah Asay, RDN. Published on September 28, 2017. Updated on April 02, 2019.


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