Eating your vegetables is good for you, but if you have low thyroid function or hypothyroidism, it's best to avoid collard greens. Some types of vegetables and foods might interfere with thyroid function, worsening symptoms. Hypothyroidism is more common among women, particularly over age 60, according to the National Endocrine and Metabolic Diseases Information Service. If you have this condition, your doctor or nutritionist can prescribe the best diet for you.
The thyroid helps control your body's metabolism; low function of this gland affects all your organs, including the brain, heart and muscles. Hypothyroidism develops slowly and you may not notice its nonspecific symptoms at first. MayoClinic.com lists symptoms including feeling tired, achy and cold, weight gain, dry skin and hair loss. It also affects your memory processes, slows your heart rate and raises cholesterol. The American Thyroid Association notes that a common cause of low thyroid function is Hashimoto's thyroiditis. This autoimmune condition occurs when your immune system reacts against the thyroid gland.
Collard greens are commonly eaten in the Southern U.S. They belong to the cruciferous family of vegetables, which includes broccoli, Brussels sprouts, cabbage, cauliflower, kale and bok choy. Although all these vegetables contain healthy nutrients, they can also interfere with thyroid function. According to the Linus Pauling Institute, collard greens and other cruciferous vegetables contain goitrogens, substances that interfere with how your body uses the mineral iodine, inhibiting the production of thyroid hormones. Iodine is necessary for healthy thyroid function and eating these vegetables, particularly when raw, can worsen your hypothyroidism.
If you have hypothyroidism, there are still plenty of vegetables you can eat. As with all chronic conditions, the right diet is important, and eating certain vegetables helps support your thyroid gland function. The Maryland Medical Clinic recommends adding seaweed to your diet. This plant food is rich in the mineral iodine, which is needed to produce thyroid hormones. Research published in the journal "Clinical Endocrinology" reports that selenium is important for thyroid tissue health. Vegetables such as tomatoes, carrots, garlic, mushrooms and corn are good sources of this mineral.
In addition to collard greens and cruciferous vegetables, other foods can also affect thyroid function. If you have hypothyroidism, the University of Maryland Medical Center advises avoiding or limiting turnips, peanuts, soybeans, pine nuts, mustard greens and cassava. Additionally, a diet high in fried foods, refined white flour, added sugars and processed foods can worsen symptoms such as low energy, weight gain and mood swings.
- National Endocrine and Metabolic Diseases Information Service: Hypothyroidism
- American Thyroid Association: Hypothyroidism
- MayoClinic.com: Hypothyroidism (Underactive Thyroid)
- University of Maryland Medical Center: Hypothyroidism
- Clinical Endocrinology: Selenium and the Thyroid Gland
- Linus Pauling Institute: Cruciferous Vegetables
Nadia Haris is a registered radiation therapist who has been writing about nutrition for more than six years. She is completing her Master of Science in nutrition with a focus on the dietary needs of oncology patients.