Diet and Weight Loss Tips for Thyroid Patients

Losing weight can be a challenging process for many people who are living with an underactive thyroid. Whether you have hypothyroidism or no thyroid after thyroidectomy (surgical removal of the thyroid) or radioactive iodine (RAI) treatment, thyroid function affects metabolism and can make weight loss an uphill battle.

Here are some diet and weight loss tips to help you reach a healthy weight when you have an underactive thyroid.

how to lose weight with thyroid disease
Verywell / Emily Roberts

Get a Diagnosis as Quickly as Possible

If your thyroid is underactive, inadequate treatment may make weight loss almost impossible, despite diet and exercise. And the longer it takes you to get diagnosed, the more weight you could gain.

When you have mild hypothyroidism, even before your TSH 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, leading to further weight gain. And, when you’re tired, you may crave and eat more sugary foods and carbohydrates for energy.

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

Look Into Optimal Treatment

In terms of weight loss, relief of symptoms, and overall good health, for many thyroid patients, it's not enough for your healthcare provider to diagnose hypothyroidism and hand you a prescription.

If you're still experiencing symptoms despite treatment, it's time to have a conversation with your healthcare provider about a more comprehensive hypothyroidism treatment plan.

Have Your Hormone Levels 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, this means you should consider having your fasting glucose and insulin levels tested, evaluated, and treated.

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

For borderline levels, reducing the sugar and carbohydrates in your diet and following a healthy carbohydrate-controlled diet can lower your blood sugar and help with weight loss. For chronically high levels, your healthcare provider may prescribe a type 2 diabetes drug like Glucophage (metformin).

Consider Hyperthyroid Treatment Options Carefully, Too

You'll need to think about whether to have radioactive iodine (RAI) versus other hyperthyroidism and Graves’ disease treatments. Weight gain after RAI is common. One study on patients who had a thyroidectomy 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. Talk to your healthcare provider about your Graves’/hyperthyroidism treatment options.

Keep in mind that most patients who have had surgical removal of the thyroid or radioactive iodine (RAI) treatment end up with hypothyroidism that requires treatment.

Have a plan in place with your healthcare provider for regular thyroid testing after surgery or RAI so that your treatment can start as soon as it's needed.

Change Your Diet

There is no one best thyroid diet, but making a significant change to how you eat is usually necessary in order to successfully lose weight when you have a thyroid condition. The best diet for you depends on your unique physiology, food sensitivities, ability to absorb nutrients, and how effective your body is at metabolizing, storing, and burning carbohydrates, among other factors.

Some approaches to consider include:

  • Cutting overall calories: Use a calorie calculating app on your phone or computer to figure out your calorie intake and whether it's close to your goals.
  • Upping your fiber intake: Getting a good amount of fiber is one of the basic tactics you can employ as a thyroid patient if you want to lose weight. It can come from high-fiber foods, supplements, or both.
  • Limiting simple carbohydrates and sugar: Try following a low-glycemic diet to avoid high blood sugar.
  • An anti-inflammatory diet: The autoimmune protocol/anti-inflammatory/AIP diet may be a good option to consider.
  • The Paleo diet: An unprocessed, low-sugar, whole foods diet, the Paleo diet, can reduce inflammation. Just make sure you're getting enough iodine.
  • Mediterranean diet: This diet is based on eating fresh vegetables, a variety of fruit, lean meats, fish, nuts, and whole grains.

What is Iodine and How Does the Supplement Work?

  • A low-carbohydrate diet or very low-carbohydrate diet: Examples include the ketogenic diet and the Atkins diet. 
  • Changing the timing of your meals: Try the intermittent fasting diet. Another approach that may be effective is the "mini-meal"/grazing-all-day approach to eating. Limiting your eating to two or three meals per day with no snacks and no food after 8 p.m. may help stimulate fat burning and help regulate hunger hormones.
  • Getting tested for food allergens: Common allergens include dairy, wheat, soy, and certain fruits and nuts. If you find you have allergies to any of these, work to eliminate them from your diet.
  • A gluten-free diet: There's a link between gluten sensitivity and celiac disease and the development of autoimmune conditions, including Hashimoto's thyroiditis. Some people have reported significant weight loss when they shifted to a gluten-free diet.

Talk to your healthcare provider before starting any of these diets. Your own health may make some diets suitable, and others unhealthy for you. For example, a ketogenic diet could be dangerous for you if you have kidney disease, while a gluten-free diet is only useful for people who have gluten sensitivity.


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.

It's generally recommended to drink eight 8-ounce glasses a day.

Try Metabolism-Boosting Exercise

For many thyroid patients, calorie restriction or even a diet overhaul isn't enough to reach a healthy weight. Hypothyroidism can lower your metabolism, which means you need fewer calories, making it more difficult to cut enough calories to generate significant weight loss.

One of the most important things you can do to raise your metabolism is exercise. Working out helps make your metabolism more efficient by burning calories and fat, reducing blood sugar levels, and balancing weight-loss-promoting hormones such as leptin.

According to the Centers for Disease Control and Prevention (CDC), healthy people of normal weight need at least 150 minutes of moderate physical activity or 75 minutes of vigorous activity (or some combination of the two) every week to maintain weight and avoid excess gain.

If you're hypothyroid and want to lose weight, you may need to do more than an hour a day of exercise.

Some thyroid patients highly recommend a muscle activation and muscle-building DVD workout program called T-Tapp. Other patients have found walking, Pilates, lifting weights, and other forms of exercise effective.

If you have to prioritize which type of exercise to do, consider strength training and exercise that builds muscle for the maximum metabolic benefits.​

Familiarize Yourself With Your Medications

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

  • Antithyroid drugs such as Tapazole (methimazole) and PTU (propylthiouracil), used to treat Graves’ disease and hyperthyroidism
  • Beta-blockers, like Sectral (acebutolol), Tenormin (atenolol), and Corgard (nadolol), which are often used to treat hyperthyroidism
  • Steroid anti-inflammatories such as prednisone
  • Estrogen and progesterone, either alone or together in hormonal birth control or in hormone replacement therapy
  • Certain antidepressants, especially Prozac (fluoxetine), Paxil (paroxetine), and Zoloft (sertraline)
  • Mood-stabilizing and anticonvulsant drugs such as those given for bipolar disorder, including 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 that you can do to help weight loss is get enough sleep. Numerous studies link sleep deprivation to a slowed metabolism and obesity. Not getting enough sleep may also make you more vulnerable to developing heart disease or diabetes.

So, if weight loss is a challenge, aim for seven or more hours of sleep every night (good advice, no matter your health goals).

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 you’re less able or motivated to exercise. This can make it harder to get rid of unwanted fat. Water retention and chronic constipation can also contribute to weight gain. Working with your healthcare provider to manage these problems can help you lose excess weight. 

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. Increasing your B12 intake, though, may help with fatigue, cognitive issues, and other problems related to insufficient B12. 

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! Regroup and start troubleshooting your diet and weight loss program by finding out more about how to bust through a weight loss plateau and exploring more tips for thyroid patients on making your diet work for effective weight loss. Consulting with a registered dietitian and a fitness trainer may also be helpful.

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6 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.
  1. Iwen KA, Schröder E, Brabant G. Thyroid hormones and the metabolic syndrome. Eur Thyroid J. 2013;2(2):83-92. doi:10.1159/000351249

  2. Schneider DF, Nookala R, Jaraczewski TJ, Chen H, Solorzano CC, Sippel RS. Thyroidectomy as primary treatment optimizes body mass index in patients with hyperthyroidism. Ann Surg Oncol. 2014;21(7):2303-9 doi:10.1245/s10434-014-3542-8

  3. Centers for Disease Control and Prevention. Physical activity for a healthy weight.

  4. Knutson KL. Does inadequate sleep play a role in vulnerability to obesity? Am J Hum Biol. 2012;24(3):361-71. doi:10.1002/ajhb.22219

  5. Ríos-Prego M, Anibarro L, Sánchez-Sobrino P. Relationship between thyroid dysfunction and body weight: a not so evident paradigm. Int J Gen Med. 2019;12:299-304. doi:10.2147%2FIJGM.S206983

  6. Boachie J, Adaikalakoteswari A, Samavat J, Saravanan P. Low vitamin B12 and lipid metabolism: evidence from pre-clinical and clinical studies. Nutrients. 2020;12(7):1925.cdoi:10.3390%2Fnu12071925

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.