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Weight gain and weight loss resistance can be one of the most frustrating side effects of medical conditions such as hypothyroidism. Regardless of the conditions, carrying excess weight can bring a handful of comorbidities that can decrease your longevity and quality of life, such as high blood pressure, increased risks for heart attacks, insulin resistance, chronic pain, and more. While most overweight would like to reach a healthier weight, it can be hard to do with diet and lifestyle changes alone. For this reason, medications like low-dose naltrexone may help support weight loss goals.
Naltrexone is a medication that may help people in a variety of ways. It is considered an opioid antagonist and is primarily used as a medication to help people with alcohol and opioid addiction. In higher doses, naltrexone can attach to opioid receptors ("Mu" receptors) to prevent people from experiencing the pleasurable effects of these substances. Taking this medication while simultaneously doing drugs or drinking alcohol can have some highly unpleasant symptoms, including vomiting and stomach pain. Thus, naltrexone essentially turns those with addiction away from their preferred substances.
In lower doses (called low-dose naltrexone, or LDN), this medication can serve several other purposes, including being an immunomodulator for people with autoimmune diseases, potentially suppressing growth in cancerous tumors, and helping people lose weight.
In a 2021 systematic review in The Archives of Medical Science, naltrexone combined with bupropion (or Wellbutrin) was effective in helping overweight subjects lose weight. While there are still questions to be answered about why naltrexone is effective for weight loss, we have a general idea of how this medication can help people shed some weight.
Firstly, naltrexone may curb appetite. Some research only reports these findings with regular doses of naltrexone and not LDN. However, with regular doses of naltrexone, subjects said that eating was less pleasurable and food did not taste as good as when the medication was not taken. While this did not directly correlate with weight loss, it can be inferred that weight loss would potentially follow if there were a decrease overall in caloric intake.
Secondly, LDN may also interfere with insulin and growth hormone. Insulin secretions may decrease while growth hormone levels may be improved. However, there have only been a few studies looking at this with small sample sizes, so more information is needed to conclude the exact role (if any) LDN has on hormone secretions.
Thirdly, and perhaps most studied, is the effect LDN has on inflammation, especially in autoimmune diseases. Low doses, starting at 0.5 mg and titrated up to around 4.5 mg, may be beneficial against autoimmune diseases like Crohn's disease and Hashimoto's. Because inflammation and autoimmune conditions may be behind weight gain (as is the case in Hashimoto's patients), there may be some benefits to using this medication if you have an autoimmune disorder.
People who have tried weight loss through dietary and lifestyle changes with no results may be considered for medication management of weight loss. However, some providers will want to see their patients, especially those in the obese category, adhere to a diet and exercise regimen before they are willing to try medication. Sometimes, weight loss cannot be achieved through these changes alone, so using naltrexone for weight loss may be an option.
More research is still needed to see if LDN is as effective as other weight loss medications. However, for people struggling with autoimmune conditions like Hashimoto's and weight gain, there may be value in trying LDN to potentially turn off cellular mechanisms that lead to autoimmunity.
The exact mechanism for how low-dose naltrexone works in autoimmune conditions such as Hashimoto's is purely anecdotal, as no studies have examined its effectiveness. LDN may help suppress inflammatory cytokines that cause inflammation of the thyroid gland, which can allow cells in the thyroid to produce more thyroid hormone and return the gland to a homeostasis state.
Side effects of LDN are rare, and fortunately, most people tolerate it well.
Reported potential or common side effects include:
- GI upset
- Muscle pain
- Joint pain
- Vivid dreams
With various symptoms such as fatigue, muscle cramping, cold intolerance, and depression, it can be much harder to exercise regularly, making weight gain problematic for those with hypothyroidism. But for obese or overweight patients, it is important to note that hypothyroidism generally accounts for only about 5-10 extra pounds. And that weight is usually attributed to fluid retention. But getting that excess fluid weight off is important to achieving a healthy weight.
Therefore, if you have hypothyroidism or Hashimoto's, one of the first things you should do is check your thyroid function. A poorly treated thyroid will lead to numerous problems and will likely add further pounds onto the scale. Once your thyroid function test is complete, your health provider should be able to recommend the right thyroid hormone replacement medication for you. More often than not, this dose will need to be adjusted over several weeks to find the optimal dose for you.
While working with medication to treat your underactive thyroid, you will also want to make lifestyle adjustments. People with Hashimoto's can suffer from nutrient absorption issues and may be deficient in specific vitamins, so it can help to work with a thyroid nutritionist to ensure you are optimizing your health through diet. Simultaneously, find something you enjoy doing for exercise that enables you to break a sweat and get moving every day. Doing something enjoyable makes you more likely to stick to it and even look forward to it.
With any autoimmune condition, it is crucial that your diet and lifestyle are shifted to help decrease inflammation within the body. If you are having trouble understanding what foods or changes would work best for you before attempting a medication such as LDN, we recommend scheduling a visit with one of our Paloma’s expert thyroid nutritionists. Our expert nutritionists will be able to help you develop a meal plan that is personalized, and optimal for your health.