Is Kale Ruining Your Thyroid?

An estimate of more than 20 million people in the United States has some form of thyroid disease, the most common being hypothyroidism (underactive thyroid). So I’m going to talk about this small powerhouse gland, as most of the information on it can be confusing.

The thyroid gland is a butterfly-shaped gland found in the front of the neck. Despite its size, the thyroid gland works together with the pituitary gland (the control center located in the brain) to produce the thyroid hormone and eventually control metabolism, growth, temperature, and energy levels.

To produce the thyroid hormone, the body also needs an adequate amount of iodine. This mineral can usually be found in dairy products, eggs, bread, vegetables, and table salt. Typically, an iodine supplement is not necessary, and I seldom recommend this to my patients. Having said this, if your thyroid tests are normal but you still experience a few of the symptoms given below, you should review your diet with your physician.

Should You Completely Ditch Goitrogenic Foods?

Certain foods have the ability to reduce the effectiveness of our medications and aggravate our medical conditions. Recently, kale and a few other healthy foods have been under the spotlight for being “goitrogenic” foods. A goitrogen is a food or substance that can disrupt the function of the thyroid gland and thyroid hormone throughout the body. But if there is one thing I want you to remember, it is that you do NOT have to quit these foods.

Research suggests that consuming these foods in small quantities has very little, if any, impact on the thyroid hormone function, particularly in areas where there is minimal iodine deficiency (United States). If you are still concerned, foods classified as “goitrogenic” can be heated to reduce or eliminate their thyroid-interfering properties.

Notable Goitrogenic Foods

• Cruciferous vegetables (broccoli, cauliflower, etc.)
• Cabbage
• Kale
• Soy
• Strawberries
• Peanuts

So before you ditch kale for good or avoid peanuts like the plague, consider heating or steaming these foods and reducing your intake to about twice a week if you have an underlying thyroid disease such as an underactive thyroid.

Common Symptoms Of An Underactive Thyroid

When individuals have an under-active thyroid or a problem with thyroid hormone production, common symptoms include the following:

• Feeling cold
• Tiredness/fatigue
• Weight gain
• Brittle nails and hair

Did you give up a goitrogenic food because you were worried about its’ effect on your thyroid? Tweet me @shilpimd and tell me about your experience.

By Shilpi Agarwal, MD