Synthroid And Weight Loss: Effects Of Thyroid Medications

Are you looking for a medication that helps with hypothyroidism? Then Synthroid (levothyroxine) may help you manage this thyroid disease.

The reversal effects of this prescription drug may also aid in weight loss and hair growth.

A healthy, balanced diet and regular exercise are key elements for losing weight. However, your underactive thyroid gland can cause weight gain if you have hypothyroidism.

Have regular tests to check your thyroid hormone levels if you have a thyroid condition.

“It’s difficult for someone with hypothyroidism to lose or maintain a healthy weight because T3, the active thyroid hormone, is low,” says Kelly Austin, ND, a naturopathic doctor at the Prime Wellness Clinic in San Diego, California. T3 is an important hormone that controls metabolic activities in the body.

Synthroid for hypothyroidism

Hypothyroidism, also known as low thyroid or underactive thyroid, is a disorder of the endocrine system. The gland does not produce enough thyroid hormones. Triiodothyronine (T3) and thyroxine (T4) are essential hormones produced and released by the thyroid gland. They are primarily responsible for the regulation of metabolism in your body.

Low thyroid levels result in cold sensitivity, dry hair, hair loss, depression, fatigue, and weight gain.

Levothyroxine, commonly available under Synthroid, is approved to treat hypothyroidism.

In 2014, the American Thyroid Association (ATA) released guidelines showing the best treatments for hypothyroidism, including levothyroxine.

If you have hypothyroidism or thyroid cancer, your doctor might prescribe levothyroxine as a treatment option. It’s safe to take levothyroxine.

According to the manufacturer, taking Synthroid helps restore thyroid hormone levels.

The chief ingredient in this medication is levothyroxine sodium. It is an artificial thyroid hormone identical to thyroxine, naturally made by the thyroid gland.

This medication comes as tablets that you swallow. The dosage of Synthroid comes under the following strengths: 25 micrograms (mcg), 50 mcg, 75 mcg, 88 mcg, 100 mcg, 112 mcg, 125 mcg, 137 mcg, 150 mcg, 175 mcg, 200 mcg, and 300 mcg. Depending on the severity of the issue, adjust your Synthroid dose as the doctor prescribes for you.

Benefits of levothyroxine

Hypothyroidism does not have a permanent solution. For this reason, you need to continue with the Synthroid medication for a lifelong period.

Normally, the doctor recommends the patient take a dose of Synthroid every morning. This drug will begin to show its effect only after a week. Then, through further tests, the doctor will recommend the right dose of this drug to supply thyroid hormones at the correct level.

Hypothyroidism can cause weight gain, hair loss, dry hair, and other symptoms. Synthroid works by helping your thyroid gland maintain a balanced amount of hormones. Thus, soon many of the symptoms will disappear. Therefore, unintentional effects of Synthroid include reverse weight gain and the prevention of hair fall.

Thyroid hormones and obesity 

Some recent studies on hypothyroid therapy with thyroid hormone substitution show that weight loss is found in obese patients. This mostly happens because of thyrotoxicosis and not because of the drugs used.

However, some research reports indicate a close relationship between Synthroid and weight gain. Hypothyroid drugs may cause weight gain because of increased metabolism in some patients if that is the case.

Another study on hypothyroid patients showed that weight loss resulting from hypothyroid medication is mainly due to water loss from the edema, another symptom of hypothyroidism.

Synthroid and other synthetic thyroid hormones used for treating hypothyroidism act by achieving a normal TSH level that falls within the range of 0.45 to 2.5 ml/L.

When you have achieved a balanced thyroid hormone level in your body, it prevents weight gain caused by poor metabolic activities.

Most studies on hyperthyroid conditions agree that weight loss results from synthetic thyroid hormones like Synthroid are minimal. Despite the use of this medication, hypothyroidism may still lead to weight gain.

Synthroid and weight loss 

A recent study from the American Physiological Society shows that the thyroid hormone (TH) is important for normal development and keeping an adult’s metabolism in check.

TR regulates cholesterol and carbohydrate metabolism through direct actions on gene expression and cross-talk with other nuclear receptors. When there is a lot of imbalance or insufficient TH, it can cause people to gain weight and have problems with being obese.

By balancing the TH level in the body, Synthroid helps reverse symptoms of weight gain.

Amber Taylor Champion, MD, of Mercy Medical Center in Baltimore, Maryland, says, “Thyroid hormone isn’t the only component involved in metabolism, but thyroid hormone is essential and is needed to run nearly every organ system in the body.”

Synthroid and Armour Thyroid and thyroid hormone are two commonly recommended drugs for hypothyroidism. These drugs are replacements for thyroid hormones that influence metabolism and cause weight loss.

Synthroid may lead to weight loss if your weight gain issue results from a low level of Thyroid hormones. However, other factors influence weight gain or loss besides the TH.

Monitoring your thyroid will help you lose weight.

Synthroid and weight gain 

Studies and anecdotal evidence show that thyroid hormones don’t have much to do with whether or not you gain or lose weight.

Synthroid helps effectively treat hypothyroidism, and this may cause some weight loss. To ensure the best results from Synthroid, create the conditions required for maximum assimilation of this drug by your body.

Doctors recommend taking Synthroid on an empty stomach after you wake up in the morning. Never take other supplements, especially those with calcium or iron, within four hours of taking this medication.

Undergo thyroid tests as recommended by your doctor to finalize the right dose of Synthroid required to resolve the symptoms of hypothyroidism. A TSH level under 2.0 is right for the resolution of the symptoms.

Keeping your TSH level at a healthy level makes it less likely that hypothyroidism will cause you to gain weight.

Should you use Synthroid for weight loss?

According to Medline Plus, Synthroid should not be used exclusively for weight loss in people with healthy thyroid function.

Using Synthroid for weight loss treatment on a long-term basis can cause life-threatening toxicities.

It is a prescription medicine that should be used only under the supervision of a qualified medical professional.

According to the Mayo Clinic report, rather than slow metabolism, factors more likely to contribute to weight gain include:

  • Eating excess calories
  • A physically inactive lifestyle
  • Family history and genetics
  • Unhealthy habits, such as routinely not getting enough sleep,
  • Hormonal factors

If you have normal thyroid function and are overweight, reducing your daily caloric intake is necessary to lose weight. If you plan your meals with a calorie deficit of 500 to 1000 calories per day, you can easily lose up to 2 pounds per week.

Combining your calorie-deficient diet with daily workouts can maintain a healthy body weight level long-term.

Side effects of Synthroid 

Taking too much Synthroid can cause adverse results. It can lead to another disease called hyperthyroidism, which involves the production of too much thyroid hormone.

According to Medline Plus, overdosing or long-term use of Synthroid can cause nausea, insomnia, heat sensitivity, and excessive sweating. It could also cause headaches, temporary hair loss, unintentional weight loss, irregular periods, and a bigger appetite.

Talk to your doctor as soon as you notice or think you might have a side effect, such as hyperthyroidism.

Hypothyroidism is a major health concern that should be treated properly and lifelong.


As per the reports of a few studies, hypothyroid medications like Synthroid may cause some amount of weight loss. However, overdosing on hypothyroidism medication can cause hyperthyroidism and weight gain.

The rate of metabolism increases with a healthy level of thyroid hormones in your body. It results in an increased rate of calorie burning in your system.

Hypothyroid patients can achieve weight loss through appropriate thyroid hormone replacements, low-calorie diets, regular exercise, and treating other diseases like diabetes and high cholesterol.

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