What Should You Eat With an Underactive Thyroid?

What should you eat if you have an underactive thyroid? For most people, the answer is reassuringly simple: a varied diet with plenty of vegetables, fruit, protein, fibre, whole grains and healthy fats.

There is no special diet that cures hypothyroidism. If your thyroid gland does not produce enough thyroid hormone, food cannot replace what your body is missing. But eating well still matters for your overall health.

Online, you may come across all kinds of rules. You might be told to avoid gluten, stop eating soy or take extra iodine and selenium. Before long, it can feel as though almost every food is something to worry about.

Fortunately, it does not have to be that complicated. A balanced way of eating that suits your needs and feels manageable is usually far more valuable than a long list of forbidden foods.

What can you eat with hypothyroidism?

There is no single meal plan that works for everyone with an underactive thyroid. The basic principles are much the same as general healthy eating recommendations.

Think vegetables and fruit, wholegrain bread, oats, rice, potatoes, beans and lentils, eggs, fish, dairy products or suitable alternatives, nuts, seeds and unsaturated fats such as olive oil and avocado.

You do not have to eat everything on this list. Perhaps you follow a vegetarian diet, have a food intolerance or simply dislike certain foods.

What matters is getting enough nutrients and choosing meals that fit your everyday life.

Which foods are good choices for an underactive thyroid?

You do not need to search for special superfoods. Many ordinary foods from the supermarket can be part of a healthy diet.

For breakfast, you could have porridge with yoghurt and fruit, or wholegrain toast with eggs. Lunch might be wholegrain bread with hummus, a bean salad or a simple omelette.

For dinner, think potatoes with vegetables and fish, brown rice with chicken and vegetables, or a meal made with lentils or beans.

Snacks can be simple too. Fruit, yoghurt or a small handful of unsalted nuts are easy options.

These foods are not intended to make your thyroid work faster. They simply help you get enough protein, fibre, vitamins and minerals.

If cooking feels difficult because your energy is low, frozen vegetables, pre-cut produce, canned beans and familiar meals you can make repeatedly may save time and effort.

The goal is not to eat perfectly every day. It is to find a way of eating that is nutritious, realistic and enjoyable.

Which nutrients are important for thyroid health?

Your thyroid needs several nutrients to function normally. Iodine and selenium are often discussed, but iron, vitamin B12 and other vitamins and minerals also play important roles in your health.

However, having hypothyroidism does not automatically mean you need supplements.

Iodine: which foods contain it?

Iodine is essential for making thyroid hormones. But more iodine is not necessarily better. Both too little and too much can cause problems.

Dietary sources include fish, dairy products and eggs. Iodised salt can also provide iodine, although its use and availability vary between countries.

In the Netherlands, bread made with iodised baker's salt is an important dietary source. Other countries may have different sources depending on local food production and salt iodisation policies.

If you avoid several major food groups or follow a restrictive diet, it may be worth checking whether you are getting enough iodine.

That does not mean you should automatically start taking iodine supplements.

High doses from supplements, kelp and certain seaweed products can be harmful, particularly for people with Hashimoto's thyroiditis.

If you are unsure about your iodine intake, speak with a healthcare professional or registered dietitian before taking supplements.

Selenium: important, but not always needed as a supplement

Selenium is involved in thyroid hormone metabolism. You can find it in foods such as fish, meat, eggs, grains, nuts and seeds.

Brazil nuts can contain particularly high amounts of selenium, but the amount varies considerably between individual nuts. Eating large quantities every day is therefore not advisable.

Although selenium supplements are often discussed in relation to Hashimoto's, there is insufficient evidence that everyone with the condition will experience fewer symptoms by taking them.

Too much selenium can also be harmful.

For most people, a varied diet is a better starting point than taking high-dose supplements without a clear reason.

Iron, vitamin B12 and vitamin D

Fatigue is often blamed on the thyroid, but it can also be associated with anaemia or low levels of iron or vitamin B12.

Vitamin D is important for general health as well. However, having an underactive thyroid does not automatically mean you have a vitamin D deficiency.

If symptoms continue, your doctor can assess whether testing for specific deficiencies would be helpful. Not every nutrient needs to be checked routinely.

Taking multiple supplements without guidance is usually not the best first step. Some supplements can also interfere with thyroid medication absorption.

Are there foods you should avoid with hypothyroidism?

For most people with an underactive thyroid, there is no universal list of forbidden foods.

You do not automatically need to stop eating gluten, soy, broccoli or cauliflower.

Gluten and Hashimoto's thyroiditis

If you have coeliac disease, a strict gluten-free diet is necessary. Coeliac disease is more common in people with autoimmune thyroid conditions such as Hashimoto's.

However, without coeliac disease or another clear medical reason, there is insufficient evidence to recommend a gluten-free diet for everyone with hypothyroidism.

Some people notice that certain foods trigger digestive symptoms. This may be a reason to review your diet with a dietitian, but it does not automatically mean gluten is damaging your thyroid.

If you suspect coeliac disease, speak with your doctor about testing before removing gluten from your diet. Avoiding gluten beforehand can make some test results less reliable.

Soy and thyroid medication

Tofu, tempeh and other soy foods can be part of a balanced diet.

However, soy may affect levothyroxine absorption when consumed close to the time you take your medication. The main concern is medication timing, not avoiding soy altogether.

If you regularly eat soy products and take levothyroxine, keep your medication routine consistent and discuss major dietary changes with your doctor or pharmacist.

Broccoli, cauliflower and other cruciferous vegetables

You generally do not need to avoid these vegetables either.

Certain compounds in cruciferous vegetables can affect how the thyroid uses iodine under particular circumstances. But normal portions of broccoli, cauliflower, Brussels sprouts and kale are not a problem for most people.

These vegetables also provide fibre, vitamins and other valuable nutrients.

There is usually no reason to remove them from your diet because of thyroid concerns.

What should you eat if hypothyroidism causes constipation?

Constipation is a common symptom of an underactive thyroid. Getting enough fibre can help support regular bowel movements.

Good sources include vegetables, fruit, whole grains, beans, lentils, nuts and seeds.

For example, you might have oats for breakfast, wholegrain bread at lunch, vegetables with dinner and fruit as a snack.

If you are not used to eating much fibre, increase it gradually. A sudden large increase can temporarily cause more gas or bloating.

Drinking enough fluids and staying physically active can also help.

If constipation continues, speak with your doctor. Digestive problems are not always caused by thyroid function alone.

Can food speed up a slow metabolism?

There is no particular food that can restore a metabolism slowed by hypothyroidism to normal.

An underactive thyroid can be associated with lower energy expenditure, fluid retention and fatigue. These changes may affect your weight.

That does not mean you need to follow an extremely restrictive diet. Strict diets can be difficult to maintain and may make it harder to get enough nutrients.

If you want to lose weight, a realistic eating pattern suited to your energy needs is usually more helpful than a special thyroid diet.

Protein-rich foods and fibre-containing meals can help you feel satisfied for longer. Regular meals may also make it easier to eat adequately without constantly making complicated food decisions.

If your thyroid is not producing enough hormone, appropriate medical treatment remains important.

Levothyroxine, food and drinks

If you take levothyroxine, what you eat matters less than you might think, but when you take your medication can be important.

Levothyroxine is usually taken on an empty stomach with water. Many preparations recommend waiting 30 to 60 minutes before breakfast, depending on the product instructions.

Coffee can also interfere with absorption if consumed too soon after taking your medication.

Calcium and iron supplements may reduce absorption as well. They are generally taken several hours apart from levothyroxine, often with a gap of around four hours.

Always follow the instructions for your specific medication and ask your pharmacist or doctor if you are unsure.

Consistency is especially important. Major changes in eating habits or medication timing may sometimes mean your thyroid blood levels need to be checked again.

Do not adjust your medication dose yourself because you have changed your diet.

Do you need a special Hashimoto's diet?

Hashimoto's and hypothyroidism are often discussed together, but they are not exactly the same thing.

Hashimoto's is an autoimmune condition that can cause hypothyroidism. Not everyone with Hashimoto's has an underactive thyroid, and not everyone with hypothyroidism has Hashimoto's.

Many special Hashimoto's diets are promoted online. Some exclude entire food groups or promise to reduce inflammation.

However, no universal diet has been proven to cure Hashimoto's or improve symptoms for everyone.

For most people, a balanced and nutritious diet remains a good foundation. Individual adjustments may be needed because of coeliac disease, allergies, a confirmed deficiency or another medical reason.

You do not automatically need to remove more and more foods simply because you have Hashimoto's.

What if you eat well but still feel exhausted?

Perhaps you already pay close attention to your diet but continue to struggle with fatigue. That can be frustrating.

However, the answer is not necessarily to eliminate even more foods.

Fatigue may also be associated with sleep problems, anaemia, nutrient deficiencies, menopause, medication or other health conditions.

If symptoms continue, even when your thyroid levels are appropriately managed, it is worth discussing possible causes with your doctor.

Healthy eating is important, but it cannot resolve every cause of fatigue.

How can you make healthy eating easier?

Healthy eating does not mean preparing elaborate meals every day or buying expensive ingredients.

A meal can include a source of protein, vegetables or fruit, a fibre-rich carbohydrate and some healthy fats.

Think porridge with yoghurt and fruit, wholegrain toast with eggs or hummus, or a dinner of vegetables, potatoes and fish, chicken or beans.

On a day when your energy is low, a simple meal is better than skipping food because cooking feels overwhelming.

Frozen vegetables, pre-cut produce, eggs, canned beans and easy-to-store ingredients can make everyday meals much more manageable.

It is also perfectly fine to repeat meals you enjoy. You do not need a completely different menu every day.

The goal is not perfect eating. It is finding a way to nourish your body that fits your life.

The most important things to remember

Most people with an underactive thyroid do not need a special diet. A varied eating pattern with enough protein, fibre, vegetables, fruit and healthy fats is a good foundation.

Aim for an appropriate iodine intake, but do not take high doses of iodine or selenium without medical advice. You do not automatically need to avoid gluten, soy or cruciferous vegetables.

If you take levothyroxine, pay attention to the timing of food, coffee and certain supplements.

And perhaps most importantly, you do not have to eat perfectly to take good care of yourself.

A nutritious way of eating that suits you and that you can maintain is often far more valuable than another restrictive thyroid diet.