Woman with slow thyroid checking her weight on a scale

Can You Lose Weight if Your Thyroid is Slow?

It can be frustrating when the scale won't budge—especially if you've been eating healthy, properly portioned meals and getting in regular exercise. There are a variety of reasons why the pounds might not be coming off. It could be that you're taking in more calories than you think, especially if you find that unhealthy food cravings sometimes get the better of you.

It's also possible that there's a medical reason that weight loss is so difficult: you might be struggling to lose weight because of an underactive thyroid.

Is your thyroid keeping you from losing weight?

The thyroid is a butterfly-shaped gland that has multiple functions, including regulating your metabolism. The thyroid controls metabolism analogous to how a thermostat controls fuel burning: when it's set to a cold temperature, there is less fuel burning and when it's raised high, there's increased fuel burning.

An underactive thyroid is associated with a lack of motivation, increased tiredness, and, most famously, weight gain. But don't get discouraged! Correcting underactive thyroid function is possible and can quickly restore healthy metabolic function, energy level and a positive mood.

What is an underactive thyroid?

Woman talking to doctor about hypothyroidism

More than 12% of Americans will end up having some type of thyroid disorder in their lifetime, and it most commonly will be due to underactive thyroid, which is also called hypothyroidism. (In contrast, only about 1% of Americans have a thyroid disease related to an overactive thyroid, otherwise known as hyperthyroidism.)

If you have this condition, your thyroid gland isn't producing sufficient levels of its hormones: either triiodothyronine (T3) or thyroxine (T4), or both. Why would your thyroid be underactive? Chances are, it's due to an autoimmune disease called Hashimoto's, which accounts for approximately 90% of hypothyroidism cases in developed countries. (Worldwide, iodine deficiency is the most common cause of hypothyroidism, but that's not a likely cause in the United States.)

In addition, many Americans have subclinical hypothyroidism, or mild or borderline hypothyroidism. Doctors sometimes overlook this diagnosis, resulting in potential consequences down the road.

How do you diagnose a slow thyroid?

Diagnosing a thyroid disorder can sometimes be complex and should be done by a physician, however you can also be proactive and order thyroid testing yourself.

To pinpoint your exact condition, your physician may run a comprehensive thyroid blood test panel consisting of multiple thyroid biomarkers. Before this, typically a simple TSH (thyroid stimulating hormone) test is performed; this is commonly used as a gateway test because an irregular TSH result alone doesn't elucidate much.

TSH is a hormone released by the pituitary gland, a pea-sized "master hormone regulator" located in the brain. TSH regulates the production of thyroid hormones T3 and T4 from the thyroid gland. When TSH levels are too high, it may indicate that the thyroid is not secreting enough T3 and T4 and your body is trying to make more TSH to fix this issue.

A thyroid antibody panel may be used to determine and also monitor Hashimoto's, a condition where your thyroid is not producing enough hormones because it's being attacked by antibodies.

Can you lose weight with an underactive thyroid?

Yes! You can lose weight, but first things first: get your hormones balanced and under control. Once you do that, weight loss may happen naturally. Your doctor may prescribe medications to replace the low levels of T4 and/or T3 hormones to help you manage the condition of Hashimoto's, which is not curable, but thankfully can be put into remission.

Once you've achieved hormone balance, if the pounds still aren't coming off, diet and exercise will help you see success on the scale, at long last.

Myths vs. facts: Best diet for a slow thyroid

Preparing healthy foods for hypothyroidism

Are there some foods people with hypothyroidism should avoid? There are quite a few myths about what you should eat if you have an underactive thyroid. Let's sift through these facts vs. fables.

  • MYTH: Don't eat "goitrogens."

    Here's some advice you should feel free to toss out: the idea that there are vegetables considered "goitrogens," meaning they hinder iodine absorption resulting in goiters, or an enlarged thyroid. Some of these foods include sweet potatoes, soy, and cruciferous vegetables like cabbage and broccoli.

    Where did this myth come from? A study from 1928 found that rabbits fed a cabbage-only diet developed goiters. But wait, don't throw away these (very healthy) foods! It's extremely unlikely that you could consume enough of these foods to end up with the same problem plaguing these rabbits…that's because "goitrogens" are only goitrogens when they are consumed raw, in large amounts, and coupled with iodine deficiency. Not only are these plants healthy, but cruciferous vegetables have demonstrated significant anti-cancer properties.

  • FACT: Gluten-free is the way to go.

    Those with Hashimoto's have an increased risk of celiac disease, which is an autoimmune condition that causes a severe reaction to gluten. Why? One hypothesis is that both autoimmune conditions have a shared immunogenetic makeup. Even if you don't have celiac, some evidence suggests that going on a gluten-free diet may benefit anyone with Hashimoto's. For example, in a pilot study of 34 women with Hashimoto's conducted over 6 months, a gluten-free diet was associated with reduced thyroid antibodies compared to a non-gluten free diet.
  • FACT: The Mediterranean diet is a great choice if you have a thyroid condition.

    The Mediterranean diet places a greater emphasis on fruits and vegetables with less meat consumption and proportionally higher intake of olive oil, nuts, and a modest wine intake. It is widely considered one of the healthiest diets as it has been correlated in many studies to reduce the risk of multiple diseases. Really, the "Med diet" is a good option for anyone, with or without thyroid issues…and in fact, following this strategy might even help your thyroid stay in balance. In an observational study of 200 people, a diet with higher meat consumption was associated with an increased risk of developing Hashimoto's, while those whose diet more closely resembled a Mediterranean diet had a reduced risk.

    In addition, some studies suggest that olive oil (a staple of the Mediterranean diet) has beneficial hormone modulating activity and has specifically been shown to stimulate T3 levels in preclinical research.

8 tips to boost your metabolism with Hashimoto’s

Man with Hashimoto’s exercises outside to boost metabolism

If you want to lose weight but have Hashimoto's, follow these 8 tips to improve your metabolism, which will make weight loss easier.

  1. Get regular exercise/activity.

  2. Sleep 7-9 hours a night.

  3. Stay hydrated.

  4. Take your thyroid hormone medications as prescribed.

  5. Make healthy food choices – opt for healthier meals with fewer calories and eat more healthy lean protein, such as fish.

  6. Avoid (or limit) alcohol consumption.

  7. Manage stress, which can affect metabolism.

  8. Increase intake of key nutrients.

    You should talk to your doctor before beginning any new regimens for Hashimoto's, but some beneficial nutrients for Hashimoto's are:
    • Iodine – If you have Hashimoto's, talk your physician before taking iodine as some evidence suggests that you may be more sensitive to low or high dosing.
    • Selenium – This mineral plays a vital role in thyroid health by assisting in thyroid hormone conversion of T4 into T3 and has been shown to help reduce thyroid antibodies.
    • Vitamin D3 – An analysis of clinical trials has shown that increased Vitamin D3 intake for 3 or more months can reduce levels of harmful thyroid antibodies.
    • Ashwagandha – This herb, which is most known for its ability to promote adrenal health, also promotes thyroid health. Ashwagandha has been shown to increase levels of both T3 and T4.

About the Author: Chancellor Faloon is a graduate of Florida State University with a bachelor’s degree in Biological Sciences. He is dedicated to disseminating guidance on achieving better health and wellness. He has had various roles in the company, but scientific writing has always been his top priority. Chance has also raced in multiple full and half marathons.


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