What's unobtrusive and undetectable to the naked eye, but can wreak havoc on your health at a moment's notice? No, the answer isn't that burrito bowl you ate a couple of hours ago. It's a little thing called the thyroid gland. According to the American Thyroid Association, an estimated 20 million Americans deal with thyroid disease, and one in eight women will develop a thyroid condition in her lifetime. A healthy thyroid keeps chugging along, making important hormones for your body; an overactive or underactive thyroid (hyper- and hypoactive, respectively) can majorly derail the train. Both can wreak havoc on your health, causing symptoms like weight gain or loss, body chills and aches, excessive fatigue, anxiety, and hair loss.
Luckily, one of the easiest ways to combat thyroid condition starts at a place we all regularly visit—the grocery store. What's on the shelf that makes thyroid disease harder to manage? What isn't as necessary to avoid after all? For guidance, we spoke to specialist Romy Block, MD, and dietitian Amy Shapiro. Read on to learn about 10 foods to avoid for thyroid disorder, and consider some other diet changes to aid digestion, too.
Meet the Expert
- Romy Block, MD, is a board-certified specialist in endocrine and metabolism medicine. She is a member of the American Thyroid Association, author of The Vitamin Solution: Two Doctors Clear Confusion About Vitamins and Your Health, and founder of Vous Vitamin.
- Amy Shapiro received her master's degree in Clinical Nutrition and her Registered Dietitian license from New York University. She is a member of the American Dietetic Association and founded Real Nutrition NYC in 2009.
White Bread and Other Gluten Products
Gluten can cause inflammation in people with thyroid disease, so if you're going to make a sandwich, count white bread out. "There is an overlap between people with thyroid autoimmune disease and celiac disease," says Block. "Those patients may benefit from a gluten-free diet." The processed flour used to make white bread is entirely void of fiber, so it won't aid digestion at all, and it's not great for your skin, either.
What to Eat Instead: There are various gluten-free loaves of bread and baked goods available, or you can try crackers made from whole grains.
It looks like the inside of the sandwich is something to avoid as well. "These foods often contain nitrates, which may cause your thyroid to absorb too much iodine and can cause enlargement of the thyroid," says Shapiro. "I recommend removing these items from your diet." Overall, cutting down on processed foods, in general, will be beneficial.
What to Eat Instead: Consider substituting rotisserie chicken, cooking up a turkey breast (Thanksgiving all year round!), or seeking alternative protein sources like eggs.
Fish and Shellfish
Seafood lovers with thyroid disorder will want to cut back on delicious catches; most fish, crustaceans, and mollusks contain high iodine levels, which can increase the severity of symptoms. In general, you need to consume large amounts to see an adverse effect, so if you're getting sushi five times a week, maybe consider pulling back a bit.
What to Eat Instead: Limit your consumption once a week, or even more sparingly.
Most dairy products are high in iodine, but balance is essential when it comes to eating dairy products for people dealing with thyroid disease. "It is important to consume adequate dairy, as [thyroid disorder] can cause brittle bones," explains Shapiro. "Adequate vitamin D and calcium are important." Enough calcium will give your hair a boost as well.
What to Eat Instead: "I recommend getting calcium from leafy greens, almonds, and fortified foods," says Shapiro. "Almond milk is a great alternative."
Soy products can interfere with some of the medicines used to treat thyroid disorder. "If you are on thyroxine for hypothyroidism, this can block out your medication if taken within three hours of your medication," says Block. Make sure to check medication labels to ensure there won't be any negative interactions and read nutrition labels when shopping. If your morning latte is non-negotiable, try alternative kinds of milk, like almond or oat.
What to Eat Instead: Look for products made with whole grains and beans instead of soy protein isolate, which is used in many meat substitutes (check out some alternative protein sources here).
Veggies like broccoli, cauliflower, kale, and sprouts all have elevated iodine levels, interfering with thyroid function. If you love a green smoothie in the morning, make sure you monitor how much of these you are consuming. You don't have to eliminate these veggies from your diet, but eating them cooked instead of raw can help the body process them better.
What to Eat Instead: Seek out veggies like bell peppers, carrots, cucumbers, lettuces, and spinach for your five-a-day fix.
High Fiber Foods
A lot of fiber in your diet can inhibit thyroid medication absorption, so make sure to take any thyroid medication a few hours before digging into that beans and rice. Although ingesting fiber from natural sources is preferable, a supplement may help monitor the exact amount you're consuming. Do not exceed the recommended 25g of fiber a day for women or 38g a day for men.
What to Eat Instead: Peeled potatoes are your new best friend, along with fruit and vegetable juices, so you're not losing out on nutrients.
Caffeine and Coffee
The lifeblood of morning hours might be a pitfall for those with thyroid disorder. "Caffeine and coffee can enhance symptoms [of thyroid disorder], so if they exacerbate your symptoms, you should limit or avoid," says Shapiro. These symptoms can include insomnia, palpitations, and tremors—the opposite of what you're after for a productive morning.
What to Eat Instead: Shapiro suggests "dandelion root 'coffee,' green tea, which has less caffeine, decaf coffee, or herbal teas."
Vegetable Oil or Other Processed Oils
Oils that are forcibly expressed from their sources ("expeller-pressed") can cause inflammation in the body. Polyunsaturated fats are the culprit, and are being studied on the cellular level and in rats for greater understanding, notes Block. Alternatively, cold-pressed oils retain more antioxidants and other benefits.
What to Eat Instead: Look for cold-pressed oils or healthier fat alternative oils, like avocado or olive oil.
It's well-documented that excessive alcohol intake can damage liver function, but the liver also eliminates waste, like excess thyroid hormone levothyroxine. Alcohol-induced liver damage could lead to a build-up of hormones or medication, which would exacerbate thyroid disease.
What to Eat Instead: There are plenty of non-alcoholic beers available, or look into sparkling grape juice or cider if the bubbly sounds better.
If the produce section's vast expanse is already too intimidating, check out meal prep services that can cater to a thyroid-friendly diet. Avoid delivery companies that use processed oils, nitrates, or sodium, notes Shapiro.
In general, foods with high iodine levels are more likely to cause potential adverse side effects in people dealing with thyroid disease, and there is no shortage of it in our food. "In general, we are not an iodine-deficient country in the U.S.," says Block. Making some of these suggested food substitutions will help control the level of iodine you consume. As a bonus, the swaps might help control your rosacea as well.
People dealing with hypothyroidism can also benefit from these diet changes. "Many of [the foods] overlap, especially those that can cause inflammation in the body, like gluten, white bread, and vegetable oils," says Shapiro. Make sure to consult with a physician or a nutritionist to meet all your dietary needs and to learn about any side effects any medications may have. Just a few of these changes can get your thyroid back on the right track.
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