If you don’t have a thyroid problem, you probably don’t spend a lot of time thinking about that butterfly-shaped gland in your neck, which helps regulate metabolism and body temperature (among other things). But thyroid disorders are pretty common—some experts believe 30 percent of women will develop one in their lifetime.

An autoimmune disorder can throw your gland out of whack, but it’s thought that lifestyle factors (like stress or diet) also can play a role. Hyperthyroidism (aka an overactive thyroid) can cause rapid weight loss, an unusually fast heartbeat, and anxiety; while hypothyroidism (an underactive thyroid) can trigger constipation, weight gain, and extreme fatigue.

If you suspect you have a thyroid problem, consult your doctor about potential treatment options. But in addition to medical treatment, there are a few lifestyle changes that can help keep your thyroid on track. We spoke to Dr. Ashita Gupta, an integrative endocrinologist at Mount Sinai West in New York City, about how to maintain a healthy thyroid. Here, her four big recommendations.

Go Mediterranean

One of the most important things you can do to maintain a healthy thyroid is eat a well-balanced diet.

“Seventy percent of our autoimmune system is found in our intestines, known as GALT, or gut-associated lymphoid tissue,” Gupta explained.

“When the intestinal lining becomes inflamed, it can trigger an immune response. Studies show that this plays a role in the development of thyroid disease.”

To help keep inflammation in check, Gupta recommends following a Mediterranean diet. She suggests aiming for four to five servings of vegetables and three to four servings of fruit each day, along with plenty of lean proteins and fatty fish, such as salmon, herring, anchovies, and mackerel. For other healthy fats, Gupta likes extra-virgin olive oil, expeller-pressed organic canola oil, sunflower oil, safflower oil, coconut oil, nuts, nut butters, and avocados.

Be wary of certain foods

No surprise here: Gupta says you should steer clear of processed foods packed with sugar and preservatives, dyes, or fat- and sugar-free substitutes.

“Processed foods including trans fats, high fructose corn syrup, MSG, and refined sugar can cause intestinal inflammation and in turn, trigger autoimmune flare-ups,” she said. “This is not specific to the thyroid, but the autoimmune system can affect various parts of the body.”

A less obvious culprit? Cruciferous veggies such as cauliflower, cabbage, kale, kohlrabi, watercress, Bok choy, and Brussels sprouts. They may be packed with good-for-you nutrients like vitamin C and folate, but eating them raw in high doses could mess with your thyroid.

“Uncooked cruciferous vegetables contain natural chemicals called goitrogens (goiter producers) that can interfere with thyroid hormone synthesis,” she said.

But don’t panic just yet, kale lovers: “The goitrogens in these foods are inactivated by cooking, or even by light steaming, so you can still consume them for their valuable antioxidant and cancer-protective effects.” (Phew!)

Consider supplements… But talk to your doctor first

You’ve probably heard that there’s a connection between thyroid health and iodine, which is essential for the synthesis of thyroid hormones.

“Worldwide, iodine deficiency is one of the causes of an enlarged thyroid gland and hypothyroidism,” Gupta said. “However, iodine deficiency is rare in developed countries due to supplementation in table salt and certain foods such as dairy and bread.”

In other words, you’re probably already getting enough iodine in your diet as is. In fact, too much iodine can trigger hyperthyroidism in susceptible individuals, so Gupta doesn’t recommend taking iodine pills without consulting your doctor.

On the other hand, if you suspect your thyroid may need a boost, speak to your doctor about taking selenium or vitamin D, both of which have been linked to improved thyroid health.

“Clinical research shows that taking 200 mcg daily of the mineral selenium can reduce anti-thyroid antibodies,” Gupta said. “Alternatively, you can get the mineral by eating one to two Brazil nuts each day.” (Yup, it’s that simple!)

As for vitamin D, some research suggests it could be important in regulating the immune system: “Severe deficiency of vitamin D may be associated with autoimmune disease, so have your physician check your vitamin D levels and advise you about supplementation if the level is below normal,” she said.

Gupta also recommends taking probiotics, which offer a whole host of health benefits. “Probiotics can help modulate the immune system, enhance gut motility, and improve intestinal permeability,” she said.

She suggests looking for over-the-counter blends that contain the active cultures Saccahromyces boulardii andLactobacillus acidophilus or eating natural sources like yogurt and kefir.

Try your best to avoid these environmental toxins

According to the National Institute of Environmental Health Sciences, long-term exposure to endocrine disruptors—chemicals that interfere with your body’s endocrine system—may trigger endocrine problems in humans. A few to be aware of are perfluorinated chemicals (PFCs) in some carpets, flame-resistant and waterproof clothing, and non-stick cookware, all of which were linked to thyroid disease in a 2010 study. Similarly, in 2011 researchers found that exposure to phthalates (found in fragranced products and soft plastics) and bisphenol-A (found in some hard plastics and canned food linings, although many manufacturers are removing them) could cause disruptions in thyroid hormone levels.

Gupta also recommends avoiding antibacterial soaps that contain triclosan, an ingredient that has altered hormone regulation in studies of animals (human studies are still ongoing), according to the FDA.

Although it would be impossible to avoid these completely, the key is to reduce your exposure as much as you can, especially if you’re pregnant or have little ones in the house—developing fetuses, infants, and children are more vulnerable to any effects of environmental chemicals.

Following some general guidelines can go a long way.

“Just use [regular] soap and water to wash your hands instead,” she said. “Use essential oils when fragrance is needed.”

Other things you can do include, choosing more fresh or frozen foods over canned, storing food in porcelain or glass rather than plastics, and keeping your home well-ventilated.