Diet and Weight Loss Tips for Thyroid Patients

An underactive thyroid (hypothyroidism) slows down the metabolism, making weight loss difficult. It can also cause weakness, fatigue, depression, and joint pain, decreasing your ability to exercise and prepare healthful meals.

The good news is that weight loss is possible with proper treatment and diet and lifestyle changes.

This article provides diet and weight loss tips to help you manage your weight when you have an underactive thyroid.

how to lose weight with thyroid disease
Verywell / Emily Roberts

Get Diagnosed

If your thyroid is underactive, inadequate treatment may make weight loss more difficult, despite eating a balanced diet and exercising.

When you have mild hypothyroidism, even before your TSH (thyroid-stimulating hormone) is elevated enough to warrant treatment, your metabolism can slow down significantly, causing you to burn fewer calories each day.

Hypothyroidism can also make you tired, achy, and less likely to exercise, making it even more challenging to manage your weight. And, when you're tired, you're more likely to crave high-sugar foods for energy.

If you have symptoms of thyroid disease, see your healthcare provider immediately and get informed about the diagnosis and treatment process.

Look Into Treatment

A buildup of salt and water causes weight gain associated with an underactive thyroid.

With proper treatment, your body weight should return to what it was before the condition developed, and your ability to gain or lose weight should be the same as individuals without thyroid problems.

If you're still experiencing symptoms after treatment, it's time to discuss a more comprehensive hypothyroidism treatment plan with your healthcare provider.

Get Tested

Research shows that hormone resistance problems—including leptin resistance and insulin resistance—may contribute to the difficulties many thyroid patients face in losing weight

And since both hyperthyroidism and hypothyroidism are associated with insulin resistance, you should consider having your fasting glucose and insulin levels tested, evaluated, and treated.

Fasting glucose above 100 may be a sign of insulin resistance and pre-diabetes, making weight loss even more difficult.

For borderline levels, limiting added sugars, practicing mindful eating, and reducing your intake of foods high in refined carbohydrates, such as pastries, french, fries, and potato chips, can lower your blood sugar and help with weight loss.

Your healthcare provider may prescribe a type 2 diabetes drug like Glucophage (metformin) for chronically elevated levels.

Consider Hyperthyroid Treatment

You'll need to consider whether to have radioactive iodine (RAI) versus other hyperthyroidism and Graves' disease treatments. Weight gain after RAI is typical.

One study looked at patients with Graves' disease who were treated with RAI over five years. Researchers found that weight gain after RAI treatment was common, and many patients developed obesity. What's more, 92% of the patients also developed hypothyroidism.

Another study on patients who had a thyroidectomy (thyroid surgery) found that those who did the surgery as their first line of treatment were less likely to become overweight or obese than those who had undergone RAI first.

Keep in mind, however, that most patients who have had surgical removal of the thyroid or RAI treatment are likely to end up with hypothyroidism that requires treatment. Talk to your healthcare provider about your Graves’/hyperthyroidism treatment options.

Change Your Diet

Adopting a well-balanced, nutrient-dense diet is often necessary to lose weight successfully.

Here are some dietary changes to consider:

  • Eat more fruits and vegetables: These foods contain an abundance of health-promoting compounds, add volume to your meals, and are low in calories.
  • Increase your fiber intake: Eating more fiber-rich foods (beans, whole grains, berries) can help relieve constipation and make you feel full longer.
  • Choose high-quality proteins: Research shows that higher protein diets may help increase your metabolism and promote satiety.
  • Focus on whole grains: Brown rice, wheat bread, popcorn, and other whole grains provide vitamins, minerals, and fiber that are vital for optimal health.
  • Eat healthy fats: Brazil nuts, in particular, are high in selenium and essential for healthy thyroid function.
  • Limit simple carbohydrates and added sugar: These foods contribute many calories to your diet yet offer little nutrients. Be sure to consume them in moderation.


Dehydration can make you feel exhausted, tired, and achy. Drinking enough water keeps your metabolism working efficiently. It can also help reduce your appetite, eliminate water retention and bloating, and improve elimination and digestion.

Although there is no official recommendation for how much plain water we should drink each day, the total amount of water recommended for healthy adults is 11.5 cups for women and 15.5 cups for men. Around 20% of this comes from the foods we eat, so women would need around nine cups of fluid daily and men around 13 cups to meet daily fluid requirements.

Try Metabolism-Boosting Exercise

Though it is not a substitute for medication, being physically active can support a healthy thyroid function, help you manage your weight, and boost your overall health.

Exercising can also help raise your metabolism, increasing the calories you burn daily. Studies suggest moderate to high-intensity exercise can suppress your appetite by balancing appetite-regulating hormones.

To reap the health benefits of exercise, aim for moderate-intensity aerobic activity 30 minutes a day, five days a week. You could also do 45 to 60 minutes three days a week. Aim to perform muscle-strengthening activities at least two days per week.

If you have not exercised in a long time, consider starting with 10-minute walks twice a week. Over time, you can increase your pace and duration.

Besides brisk walking, moderate-intensity aerobic exercises include water aerobics, cycling, tennis, raking the yard, and mowing the lawn.

Examples of muscle-strengthening exercises include lifting weights, using resistance bands, bodyweight exercises (pushups, squats, etc.), and heavy yard work, like shoveling or digging).

Familiarize Yourself With Medications

Some drugs healthcare providers prescribe for thyroid-related symptoms, or other conditions can cause weight gain. The following medications are associated with weight gain:

  • Antithyroid drugs: Tapazole (methimazole) and PTU (propylthiouracil)
  • Beta-blockers: Sectral (acebutolol), Tenormin (atenolol), and Corgard (nadolol)
  • Steroid anti-inflammatories: Prednisone
  • Estrogen and progesterone: Alone or together in hormonal birth control
  • Antidepressants: Prozac (fluoxetine), Paxil (paroxetine), and Zoloft (sertraline)
  • Mood-stabilizing and anticonvulsant drugs: Lithium, Depakote (valproate), and Tegretol (carbamazepine)

If you're taking any of these medications and you're gaining weight, talk to your healthcare provider about your concerns. Never stop taking a medication without your healthcare provider's input.

Thyroid Disease Doctor Discussion Guide

Get our printable guide for your next doctor's appointment to help you ask the right questions.

Doctor Discussion Guide Woman

Get Enough Sleep

One of the most important things you can do to help weight loss is getting enough sleep. Numerous studies link sleep deprivation to a slowed metabolism and obesity. Not getting enough sleep may make you more vulnerable to developing heart disease or diabetes.

It is a good idea to get at least seven hours of sleep each night, especially if weight loss is a challenge.

A Word From Verywell

If you feel like you've been doing everything right and you're frustrated by the scale refusing to budge, here's one last diet tip: Don't give up. Weight loss is very complex and challenging. A condition such as thyroid disease can make weight loss even more difficult. If you're feeling stuck, consider consulting with a registered dietitian who has experience working with people who have thyroid disease.

Frequently Asked Questions

  • Why is it hard to lose weight with hypothyroidism?

    Hypothyroidism can slow your metabolism and cause fatigue, so you don’t burn calories efficiently and are less able or motivated to exercise. Water retention and chronic constipation can also contribute to weight gain.

  • Can B12 supplements help someone with hypothyroidism lose weight?

    There's an association between hypothyroidism and B12 deficiency, and there's a connection between low levels of B12 and obesity. However, it's not clear whether this deficiency causes weight gain, and it hasn't been shown that B12 supplements will help you lose weight.

Originally written by
Mary Shomon
Mary Shomon
Mary Shomon is a writer and hormonal health and thyroid advocate. She is the author of "The Thyroid Diet Revolution."
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15 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading
  • Braverman L, Cooper D. Werner & Ingbar's The Thyroid: A Fundamental and Clinical Text. 10th ed. Philadelphia, PA: Lippincott Williams & Wilkins/Wolters Kluwer; 2012.

  • Garber J, Cobin RH, Gharib H, et al. Clinical Practice Guidelines for Hypothyroidism in Adults: Cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Endocrine Practice. 2012 Nov-Dec;18(6):988–1028. doi:10.4158/EP12280.GL.

  • Iwen KA, Schröder E, Brabant G. Thyroid Hormones and the Metabolic Syndrome. European Thyroid Journal. 2013;2(2):83–92. doi:10.1159/000351249.

  • Knutson KL. Does Inadequate Sleep Play a Role in Vulnerability to Obesity? American Journal of Human Biology. 2012;24(3):361–371. doi:10.1002/ajhb.22219.

  • Laurberg P, Knudsen N, Andersen S, Carlé A, Pedersen IB, Karmisholt J. Thyroid Function and Obesity. European Thyroid Journal. 2012;1(3):159–167. doi:10.1159/000342994.

  • Schneider DF, Nookala R, Jaraczewski TJ, Chen H, Solorzano CC, Sippel RS. Thyroidectomy as Primary Treatment Optimizes BMI in Patients With Hyperthyroidism. Annals of Surgical Oncology. 2014;21(7):2303–2309. doi:10.1245/s10434-014-3542-8.