Diet for Pregnant Women with Hypothyroidism

The diet for pregnant women with hypothyroidism is an important treatment to take in order to avoid complications in the gestation period.
Diet for Pregnant Women with Hypothyroidism

Last update: 16 February, 2023

Surely you’ve heard of the thyroid gland. Well, it’s a very active gland, which releases hormones that help the development of the baby’s brain. However, in some cases and during pregnancy, its activity may decrease, producing hypothyroidism. If this occurs, a diet for pregnant women with hypothyroidism is required to ensure the good health of the mother and the child.

This thyroid disorder can cause certain extreme complications, such as preeclampsia or miscarriage. For this reason, it’s crucial to know the best diet that allows the reactivation of the gland. Keep reading to find out what foods are key to its functioning.

What is hypothyroidism?

To understand what hypothyroidism is, we must first refer to the thyroid gland. The National Institute of Diabetes and Digestive and Kidney Diseases explains that the thyroid is a butterfly-shaped gland located at the base of the neck.

It produces the thyroid hormones T3 and T4, which control the use of energy by all the body’s tissues (i.e. metabolism).

During the first trimester of pregnancy, T3 and T4 are supplied to the baby through the placenta, as the fetus doesn’t produce them. It’s from week 12 or 14 that the fetal thyroid begins to produce them.

But what is hypothyroidism? When the gland decreases its activity significantly and stops producing enough hormones, then we’re talking about this condition. In this context, many body functions are reduced.

What are the symptoms during pregnancy?

A pregnant woman with hypothyroidism.
There’s usually no difference in the symptoms of hyperthyroidism between pregnant and non-pregnant women.

Pregnant women with hypothyroidism experience the same symptoms as anyone else with the disease. Symptoms include difficulty with cold temperatures, muscle cramps, severe constipation, extreme tiredness, and difficulty concentrating. A good proportion of pregnant women with hypothyroidism have very mild symptoms or none at all.

Does it produce complications?

If it’s detected in a pregnant woman and the appropriate treatment isn’t given, some complications may appear such as preeclampsia, spontaneous abortion, fetal death, low birth weight, anemia, and, on rare occasions, congestive heart failure.

Diet for pregnant women with hypothyroidism

Diet is considered a treatment in conjunction with pharmacological treatment in thyroid disorders. While medical treatment supplements synthetic thyroid hormones, diet through food tries to reactivate the function of the gland.

For these hormones to be produced, an adequate supply of iodine through food and a protein called thyroglobulin, which is formed from the amino acid tyrosine, is required.

Once hypothyroidism has been diagnosed, the first thing to do is to maintain regular visits with your obstetrician and visit a nutritionist to help plan the diet. What foods should be eaten? We’ll explain below.

The diet should contain enough iodine

According to the WHO, one-fifth of the world’s population may suffer from iodine deficiency. Their daily requirement is 100 to 200 micrograms per day. In the case of pregnant women with hypothyroidism, up to 300 micrograms per day may be prescribed.

This is a mineral that’s found in the soil, so those vegetables that grow in areas where iodine is abundant will be the best sources in the diet.

Seafood such as fish and shellfish are also an important source of this substance. The same happens with algae, but be careful, because their concentrations are so high that they could cause more disorders in the gland.

Another quick way to enrich the diet with iodine is to use iodized salt in preparations. Dairy products are also considered a good source, as long as they’re fortified.

As a preventive measure, experts suggest  using supplements with an additional 150 micrograms of iodine to ensure that the pregnant woman receives enough, especially if she doesn’t have access to iodized salt.

Eliminate raw biogenic foods

A biogenic food is a food that interferes with the body’s utilization of iodine. Some foods contain naturally occurring dioxygenic substances such as thiocyanates and their precursors, called cyanogenic glycosides. They’re considered antithyroid and are present in:

  • Cassava
  • Cabbage, cauliflower, broccoli, brussels sprouts, and cabbages
  • Radish, carrots, and spinach
  • Peanuts, pine nuts, and walnuts
  • Soy and its derivatives are also considered bociogenic when iodine intake isn’t adequate.
  • Mustard seeds

However, this photogenic effect is completely eliminated when the food is cooked or fermented. In other words, pregnant women with hypothyroidism can eat these foods as long as they’re subjected to heat. Nuts can be roasted.

Increase food sources of vitamins A and D and zinc

A woman chopping fresh vegetables.
There are a variety of foods that can be consumed when hypothyroid.

Carrots, bell peppers, sweet potatoes, mango, and other yellow or orange vegetables are sources of beta-carotene and vitamin A.

Fortified skimmed dairy products and oily fish such as salmon, trout, sardines, and mackerel, among others, provide sufficient vitamin D. In addition, solar radiation is the most practical and quickest way to activate this vitamin.

Zinc is found in foods such as seeds, cereals, and legumes. Meat, poultry, and fish are also considered a good source of this mineral.

The diet for pregnant women with hypothyroid should NOT include the following foods

  • Processed foods high in saturated fat or sugars can lead to weight gain, which further affects the health of pregnant women with hypothyroidism.
  • Eliminate sausages and other processed meat products, fast foods, cream cheese, sweetened beverages, chocolate, confectionery, hydrogenated margarine, or trans fat products.
  • Sugary drinks such as sodas, industrialized juices, and energy drinks should be excluded from the diet plan.
  • Snacks with high sodium content increase the risk of hypertension, which can be aggravated in thyroid disorders.
  • In cases of hypothyroidism during pregnancy, it’s best to completely eliminate caffeine, as it interferes with the absorption of the synthetic drug prescribed by the doctor.

Last recommendations

With the foods to include or exclude in the diet for pregnant women with hypothyroidism, the metabolic disorder of hypothyroidism can be prevented.

It’s important that this problem is diagnosed in time by your treating physician and that you adjust your diet to the plan suggested by a nutrition specialist.

You should maintain an adequate intake of iodine, excluding those cruciferous vegetables that, in their raw form, may interfere with its absorption. They should be cooked, fermented, or roasted.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.



This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.