Thyroid Medications and Weight Loss

Synthroid, weight loss, diet, weight gain, hypothyroidism, hypothyroidism medication

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It can be challenging to lose weight when you have hypothyroidism, and your thyroid medications may have something to do with it. Getting the dose just right is critical, as is the timing of when you take it. In some cases, you may need to supplement with another medication. For the sake of your overall health, as well as your weight-loss efforts, it's important to work with your doctor to get the most out of thyroid hormone therapy.

Aiding Absorption

For thyroid medication to be effective, it needs to be absorbed properly by your body. Here's how to ensure that nothing interferes with maximum absorption:

  • Take your medication in the morning and wait at least an hour before drinking regular or decaf coffee or milk, or eating breakfast. Wait at least three to four hours before taking any supplements that contain iron or calcium, or before consuming products such as calcium-fortified juice.
  • If you are taking Synthroid brand levothyroxine, keep in mind that Synthroid contains both acacia and lactose, which are allergy-provoking ingredients for some people. If you suspect you might be allergic to these, consider switching to another brand. 
  • If you have digestive issues or any digestive conditions, such as irritable bowel syndrome or Crohn's disease, talk to your doctor about Tirosint. This is a specialized, hypoallergenic gelcap containing liquid levothyroxine that is designed to improve absorption in certain patients.

Finding the Right Dose

It's important that you take the right amount of Synthroid or another thyroid hormone replacement drug. Some practitioners may prescribe only enough medication to get your thyroid stimulating hormone (TSH) level into the upper end of the reference range, close to the cutoff for hypothyroidism.

This may not be enough to resolve your symptoms or optimize your metabolism. Many thyroid patients and practitioners find that a TSH level below 2.0 is optimal for resolution of symptoms. If your TSH is at the higher end of the reference range, talk to your doctor about increasing your dosage of thyroid medication.

If you're hypothyroid and need to lose weight, talk to your doctor to make sure you're on the right dose of the right drug and are taking it at the right time. With some fine-tuning of your treatment, your weight-loss efforts should begin to pay off.

When One Drug Isn't Enough

Levothyroxine drugs like Synthroid are synthetic forms of the thyroid hormone thyroxine, also known as T4. When everything works perfectly, your body should convert the T4 into the second key thyroid hormone, triiodothyronine, known as T3. T3 is the active hormone that helps facilitate energy and helps oxygen reach your cells.

Research shows, however, that in a subset of thyroid patients, this conversion process is faulty. Whether due to genetic changes, stress, or nutritional deficiencies, these patients fail to effectively convert enough T4 into T3.

If you fall into this category, you may find that even after being treated with levothyroxine, you are gaining weight or unable to lose weight. You may also have a number of other hypothyroidism symptoms, such as fatigue, hair loss, or brain fog. If this is the case, you might benefit from the addition of T3 to your levothyroxine.

  • Ask your doctor to test your T3. If you have low or low-to-normal levels, you may be a candidate for supplementation with Cytomel (liothyronine) or a compounded, time-released formulation of this medication.
  • If your free T3 levels are normal, but you have noticeable symptoms of hypothyroidism, including difficulty losing weight, ask to have your reverse T3 tested. High levels of this inactive form of T3 may interfere with your body's ability to deliver active T3 to your cells and organs. Adding T3 to your treatment, in this case, may help resolve your symptoms.
Understanding Thyroid Function Tests and Normal Ranges

Rethinking Medications

Some thyroid patients try a levothyroxine drug, add a T3 drug, and still can't resolve symptoms. If that is your experience, you may want to talk with your practitioner about trying a natural desiccated thyroid (NDT) drug like Nature-throid or Armour Thyroid. There is also a generic version of NDT known as Thyroid NP. 

There is limited research on NDT, but one study found that NDT was a safe and effective alternative to levothyroxine drugs, and resulted in more weight loss for patients. 

A Word From Verywell

While it's not related to Synthroid or other thyroid drug treatment, there is a link between hypothyroidism and risk of increased blood sugar levels and type 2 diabetes. If you have optimized your hypothyroidism treatment and are still struggling to lose weight, talk to your doctor about having your fasting glucose and hemoglobin A1C (HA1C) tested. If levels are high, changes to your diet and exercise habits, as well as type 2 diabetes medications such as metformin, may help normalize your blood sugar levels and make your weight loss efforts more successful.

The Connection Between Thyroid Disease and Diabetes
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