Diet after thyroid cancer

People with thyroid conditions can’t manage their condition through diet. But, eating the wrong foods or taking the wrong supplements can cause trouble.

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Among the foods to go easy on are soy, kelp and dietary supplements like iodine and selenium, says endocrinologist Christian Nasr, MD. “There is a lot of literature on what people shouldn’t do,” he says.

Should people with thyroid problems avoid these foods?

Soy: If you have hypothyroidism, yes. Eating too much soy causes problems only for those with hypothyroidism, which occurs when your thyroid gland does not make enough thyroid hormones, Dr. Nasr says.

The main problem is that soy may hinder absorption of the hormones that such patients take.

“Some studies show that if you eat a lot of soy, or drink a big glass of soy milk, within one hour of taking a thyroid hormone, it might affect absorption,” Dr. Nasr says. “Many individuals depend on a consistent absorption of those hormones to achieve a steady state.”

Generally, experts recommend that people who have a borderline thyroid — one that’s a little underactive but you’re still trying to preserve thyroid function — do not to consume large amounts of soy every day, he adds.

Turnips and root vegetables: No. These vegetables are sometimes thought to cause thyroid problems, but that’s not the case, Dr. Nasr says. They are good for your diet, regardless of any thyroid issues.

One root vegetable that is the exception is cassava, a common staple in certain parts of Africa. This plant “is known to produce toxins that can slow an already underactive thyroid, especially in the presence of an iodine deficiency,” Dr. Nasr says. “But that’s not relevant here in the United States, unless you cook cassava and you eat it every day.”

Kelp: No, but don’t take it in supplement form. People with thyroid issues should not have more than an average daily recommended intake of 158 to 175 micrograms of kelp per day, Dr. Nasr says. The concentration of kelp in foods is generally not enough to cause a problem, but a kelp capsule can contain as much as 500 micrograms, he says. “Those recommendations to go easy on kelp are for people who don’t understand and take three capsules per day. If you eat an average amount of kelp once a day, that’s not a problem.” Pregnant women especially should avoid ingesting large amounts of kelp, as it may put them at risk for developing fetal goiter, he adds.

Cabbage and cruciferous veggies: Yes. Even though they are good for us, cabbage and other cruciferous vegetables eaten raw in large quantities, especially in the context of iodine deficiency or borderline iodine levels, can result in hypothyroidism. These vegetables generate a substance that competes with the uptake of iodine by the thyroid.

Should people with thyroid problems avoid these supplements?

Iodine: Yes. Avoid it as a supplement whether you have hyperthyroidism or hypothyroidism. The effect of iodine supplements can vary by person, causing the thyroid to produce either too much or too little hormone.

Certain alternative medicine websites or doctors tell patients that iodine is good for your thyroid, Dr. Nasr says, but “if there is anybody who shouldn’t take iodine, it is thyroid patients.” Such claims are made because iodine deficiency is the No. 1 cause of thyroid conditions in the world, he says. But that’s not true in the U.S., where we have iodine in our diets. Iodine is added to many foods, and not just salt, he says.

However, Dr. Nasr says that people on restrictive diets may consider adding a daily multivitamin that contains the recommended daily allowance of iodine.

He also assures patients not to worry that you are getting too much iodine from everyday foods. “You would have to eat a ton of it to cause problems,” he says. “It’s not, ‘don’t eat anything with iodine.’ It’s, ‘don’t eat a bunch of iodine.’ And patients should be careful with iodine-concentrated supplements.”

Selenium: No, but don’t take more than 200 micrograms per day. Selenium, which is needed to support efficient thyroid function, is not something you would typically find at the grocery store, but an alternative medicine doctor might prescribe it, Dr. Nasr says. You can also get it in foods like fish, Brazil nuts, meat and poultry. A selenium supplement is OK to use “as long as you’re not overdoing it,” he says.

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Thyroid nodules are the most common endocrine problem in the United States. According to the American Thyroid Association, one out of 10 people will develop one of these small lumps on their thyroid glands at some point in their life. Most cause no symptoms, so you probably wouldn’t be aware that you had one until a doctor found it during a routine check-up.

Once a nodule is discovered, your physician will probably recommend thyroid function tests – blood tests to show whether or not the nodule is interfering with the normal workings of the gland. You may also need a thyroid scan and a fine needle aspiration (FNA) biopsy to make sure that the nodule is not cancerous. (Only about five percent are a cause for concern and eed immediate attention). As long as the nodule is benign and isn’t growing, the only recommendation will likely be watchful waiting with periodic medical exams and thyroid function tests.

I don’t know of any supplements or dietary measures that can help control small thyroid nodules, but I checked with Seymour Reichlin, M.D., Ph.D., a distinguished endocrinologist and retired research professor of medicine at the University of Arizona. He told me that since iodine deficiency can cause nodular enlargement of the thyroid (also called goiter), it is important to be sure that your dietary intake of that trace mineral is adequate. However, he said that he doesn’t believe that taking supplemental iodine will reduce existing nodules, although it might prevent new ones from forming. And he cautioned that no one with known nodules should take iodine supplements without medical supervision, especially if they are older.

Andrew Weil, M.D.

Foods to eat, and avoid, for managing thyroid conditions

The thyroid gland just might be the most understated organ in the human body.

Its impacts are far-reaching, from regulating your metabolism and controlling growth to determining your mood and controlling perspiration. Individuals with thyroid problems can have excessive fatigue, memory loss, rapid weight gain or loss, muscle aches, constipation, dry skin and other symptoms.

According to the American Thyroid Association, “The thyroid gland is a butterfly-shaped endocrine gland that is normally located in the lower front of the neck. The thyroid’s job is to make thyroid hormones, which are secreted into the blood and then carried to every tissue in the body. Thyroid hormone helps the body use energy, stay warm and keep the brain, heart, muscles, and other organs working as they should.”

Thyroid conditions, however, often can be managed naturally through one’s diet. Knowing what to eat, as well as what to avoid, has an immense impact on whether conditions are mitigated or recurring.

As a doctor of functional medicine, I prescribe natural remedies to treat the underlying cause of a patient’s symptoms, not necessarily the symptoms themselves. So for patients with overactive or underactive thyroids, I examine their medical history, diets and exercise regimens. Food often is a trigger for their thyroid conditions.

What’s unusual about diets for thyroid patients is that certain foods considered “healthy” by many doctors – kale, broccoli and strawberries, for example – can actually prevent the thyroid from functioning properly for some individuals, and the same food item can have opposite results in those with underactive thyroids as opposed to overactive thyroids.

Underactive thyroids (hypothyroidism) are much more common, so we’ll focus on that. Hypothyroidism occurs when your body is not producing an ample supply of thyroid hormones, so proper food choices can help relieve that deficiency.

Selecting foods that contain iodine, zinc and selenium can spark activity in an underactive thyroid, so incorporating foods high in those nutrients is important. Foods on the OK list for those with hypothyroidism include:

  • Whole eggs, including the iodine-heavy yolk
  • All types of seafood, including salmon, tuna, shrimp and halibut
  • Cooked cruciferous vegetables, which include broccoli, cabbage and Brussels sprouts. Sweet potatoes and quinoa also can be advantageous.

Most cases of hypothyroidism are caused by an autoimmune disease. If that’s the case, remove gluten from your diet, and avoid dairy products like milk, yogurt, cheese and ice cream. I often recommend individuals with underactive thyroids eliminate all gluten, dairy, soy, corn, sugar, beans, nuts and seeds for a 30-day period, which helps the body start to get back on track.

Call a Doctor

Anyone with concerns about their thyroid function and dietary requirements should see a doctor and discuss how other existing conditions, like an autoimmune disease, can impact your nutrition plan.

Genetics, medical history and environmental toxins can negatively impact thyroid conditions, but your diet is one factor you can control. One technique employed by many suffering from thyroid conditions is attempting to regulate blood sugar levels by eating similar-sized, small-portioned meals at the same time each day. That might not sound appetizing, but preventing blood sugar swings is beneficial to the thyroid.

To schedule an appointment and discuss your personalized thyroid-friendly diet, please call our office at 239-649-7400 or submit an appointment request through our online form.

I have been doing research on different medical conditions and how to heal them naturally with diet. I found that the best anti-cancer diet is one that treats inflammation. ( Inflammation is the cause of a lot of medical conditions including arthritis.)That would be to lower fat( not totally eliminate it)and lower sugars and replace them (high fat foods and sugar, high fructose corn syrup, etc) with natural replacements such as olive oil, or natural sweeteners (not chemical sweeteners) or sugars. Berries are good, herbs and spices like onion , garlic, parsley, oregano, basil, ginger, tumeric, and seracha sauce. Green tea is good and you can buy tea made from ginger and tumeric at Whole Foods. Cruciferous vegetables like brussel sprouts, cabbage, etc.are good. We need fat in our diet and they use to say eat the extra lean meats but in reality we need some fat in our diet as well as cholesterol because our body needs it to work properly. We should be buying lean ground beef instead of regular or extra lean. Instead of duck replace it with chicken or turkery. Fatty fish like fresh water salmon is also good. One of the other vegetables that seem to be on all special diets as it is almost considered a miracle vegetable and that is Kale. Kale is suppose to be real good for you..
Now if you are going to have radiation or are currently going through radiation follow whatever diet your doctor or nutritionist gave you or refer to the thyca website for the low iodine diet. I did not have to have radiation so I cannot comment on that and only point you in that direction.
Another thing regarding proper nutrition, if you just cut out the commercially manufactured products from your diet and only eat one ingredient foods, you will do well. In other words, omit the lunchmeat with all its many ingredients and chemicals and opt instead for a sandwich made of cooked fresh turkey or corned beef. Instead of that store bought dessert, have fruit instead. Other than that I do not have any other special information. Everything I have learned I have learned from PBS, medical shows, the internet research. I do not follow fad diets or information. I am the one wh would not even attempt the Adkins Diet even though everyone I knew loved it. You just have to think of it as a lifestyle and not a diet. That helped me when I had to lose a lot of weight several years ago. Good luck.

August 2008

Q: Thank you very much for your excellent Web site. It is easy to navigate and has a lot of very good information, including referral information. I would like to air one frustration, however; there does not seem to be much patient information regarding what to expect after a total thyroidectomy. As a health care professional for many years, and now 18 months post-thyroidectomy, I am surprised at the dearth of information regarding this issue. Except for calcium issues, there is very little on the Web. I would imagine the population needing this information would be relatively small, but it would make live so much easier knowing the emotional and physical aspects of your life that can be changed by this surgery and how to deal with these issues. Thanks again for your good work.

A: Thyroidectomy (surgery to removal all or part of the thyroid) may be required for patients with hyperthyroidism, goiter, thyroid nodules or thyroid cancer.

Thyroid operations can last from 45 minutes to 3 hours. The length of the operation is determined by whether one or both lobes are removed, and by the complexity of the operation. For example, it takes less time to remove a small thyroid nodule than to remove the whole thyroid and nearby lymph nodes in a patient with thyroid cancer. Depending upon local practice and the extent of the operation, patients may remain in the hospital overnight. Immediately after the thyroid operation, most people will have a sore throat from the breathing tube used for anesthesia.

Pain at the incision is minimal (most liken it to a sore throat), and patients generally require only mild pain medication (for example, acetaminophen) by the first day after the operation. It may be more comfortable to eat soft foods for a few days. Driving is not safe while taking pain medications that can cause drowsiness, and patients should not drive until they can turn their head comfortably from side to side (this may take up to a week). There may be some numbness around the incision immediately after the surgery; in most cases this resolves as the nerves in the skin heal. The wound healing sometimes causes itching that can last for several weeks. The incision will leave a scar, although these scars usually heal quite well. Patients should avoid sun exposure to the wound for about six months to improve the cosmetic outcome. Using vitamin E on the skin may also help to improve the appearance of the scar.

For most patients, walking and normal routines can resume the day after the operation, but vigorous activity and heavy lifting are not recommended for two weeks. Depending on their job type, most people will need to take 1-2 weeks off work after thyroid surgery. Some patients experience a sensation as though there is a lump in the throat upon swallowing; this is normal and it spontaneously subsides over time. Some patients may notice subtle voice changes or the voice may tire by the end of the day; these voice alterations generally resolve within 2-3 months. If voice changes persist, the surgeon or endocrinologist should be advised, as further evaluation may be necessary.

During the operation, the parathyroid glands (most people have four) are separated from the thyroid gland and hopefully preserved. However, the parathyroid glands may be located within the thyroid gland or attached to the thyroid capsule. Therefore, one or more of the parathyroid glands might be injured or removed. The parathyroid glands regulate the body’s calcium levels, and they can under-perform for several weeks after the operation. Therefore, the patients’ blood calcium levels are followed in the hospital and after discharge. Calcium, and sometimes vitamin D, supplements may be required, especially if both thyroid lobes are removed. In most cases, these supplements can be stopped within several weeks, once the parathyroid glands heal and their normal function returns. Patients require lifetime thyroid hormone replacement when the entire thyroid gland (both lobes) is removed, and sometimes when even just one lobe is removed. Patients who have some thyroid tissue remaining after the operation may not immediately need thyroid hormone, but they should be monitored periodically for the rest of their lives for the development of hypothyroidism. The endocrinologist will adjust thyroid hormone and calcium/vitamin D supplements, as indicated by blood tests.

Medical Disclaimer The information contained in or made available through the American Thyroid Association Website is not intended to replace the services of a trained health professional or to be a substitute for medical advice of physicians. The user should consult a physician in all matters relating to his or her health, and particularly in respect to any symptoms that may require diagnosis or medical attention. The American Thyroid Association makes no representations or warranties with respect to any information offered or provided within or through the American Thyroid Association Website regarding treatment, action, or application of medication.
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What to Expect After Thyroid Surgery


Most patients will be eating, drinking, and walking around the night of their surgery. Typically, there is not a lot of pain involved with thyroid and parathyroid surgery. Rarely narcotic pain medication will be required, but it will be available to you if needed. Most patients only need acetaminophen (Tylenol) for discomfort. You will stay overnight for observation and be discharged to home usually by 11:00 AM the morning after surgery.


The incision is closed with dissolvable sutures internally and you will not be able to see them. On the outside, the incision will also be closed with either surgical glue or surgical paper tape called steri-strips. A light bandage consisting of a gauze pad and a clear plastic covering will be placed over your incision after surgery. This bandage may be removed 48 hours after you leave the hospital. If you have steri-strips on your incision, leave them in place until they begin to fall off naturally. If they have not fallen off in 7-10 days, you may gently remove them. If glue was used, it will appear as a white crusty white or yellow material covering the incision. You may notice tiny pieces of yellow material on your washcloth when you gently clean you incision.


The incision will be slightly raised and there may be swelling and light bruising at the incision site. This is normal for several weeks after surgery and will resolve over time. You may also feel a sensation of swelling or firmness that will also resolve over time.


It is normal to experience numbness under your chin after surgery, especially around the incision. This will get better over time. However, if you feel numbness and tingling around your mouth or in your fingertips or toes call our office.

Wound Drainage

You may experience slight oozing of a watery, reddish color of fluid a day or two after surgery. This is normal. Please call the office if the drainage is thick and yellow (like pus), or you develop a temperature over 101.5F, or if your incision becomes red and warm.

Incision Scar

You may feel a firm ridge directly over the incision. This is normal and will soften and go away when healing is complete usually in 3-6 months. All incisions are sensitive to sunlight. The ultraviolet light of the sun and tanning booths will darken the scar area in the first year. Always use sunscreen.


You may shower the day after surgery. Try not to get the bandage totally soaked. Once the bandage is off, it is still OK to shower. Still try not to totally saturate the incision. You should not go swimming or soak in a tub or hot tub for at least a week.


You may eat whatever you choose. You may prefer softer foods and liquids initially if you have a sore throat. Advance you diet as you see fit. Some patients experience minor changes in swallowing that improve over time. You may feel there is a lump in your throat when you swallow. This sensation will decrease with time.

Sore Throat/Cough

This is normal to experience after surgery and will often last up to 5 days after surgery. Lozenges and a softer diet may be helpful until this resolves. You may also feel like you have phlegm in your throat and need to cough. This is due to the irritation of the tube in your windpipe during surgery. It should clear up in 4-5 days.


Your voice may be hoarse or weak at first because the surgery took place near the voice box but usually recovers within weeks. Some patients also notice a change in the pitch of their voices that affects singing. Rarely these changes are permanent.

Neck Stiffness

You may experience stiffness/soreness in your neck, shoulder, or back and may experience tension headaches. These may take a few days or weeks to go away completely. You should not drive until you can comfortably turn your head from side to side. It is a good idea to gently perform neck exercises to help keep it from getting stiff looking side to side, up and down or moving your head in a small circle. You may apply a warm compress or heating pad to your shoulder and back to alleviate stiffness.

Pain Management at Home

Take NSAIDS like ibuprofen (Motrin, Advil), naproxen (Naprosyn, Aleve) or acetaminophen (Tylenol) for the first 3-5 days as needed. Take medication as directed on the medication container. To prevent acetaminophen overdose, do not take acetaminophen when you are taking the pain reliever – Percocet – that was prescribed on your discharge from the hospital. They both contain acetaminophen. If you take the Percocet or any other narcotic – DO NOT drive a car or drink alcohol.

Back to Normal Activities

Most patients return to their daily activities in a few days and work in about a week, with some limitations. Strenuous activity and heavy lifting should be avoided for at least two weeks.

New Medications

Calcium Supplement

Your body’s blood calcium level may fall after a total thyroidectomy or parathyroidectomy. The parathyroid glands that regulate your blood calcium levels may not function properly after surgery. This is common and usually temporary. You will receive specific instructions on hospital discharge on how much calcium you need to take. Symptoms of a too low calcium level include numbness and tingling in your hands, feet, and around your lips. Some patients experience muscle cramps. Typically you will take calcium carbonate 1250 mg one to three tablets a day. Do not take calcium carbonate within 1-2 hours of taking other medications. If any questions about drug interactions, be sure to ask the pharmacist or doctor. Some brands of calcium carbonate are Os-Cal 500 and Tums.

Thyroid Hormone

If you have had a thyroid operation, you may be prescribed a thyroid hormone replacement called Synthroid (levothyroxine is a generic form). You must take this medication every day and on an empty stomach. Take in AM when you first get up and wait to eat anything for 30 minutes to one hour. A blood test will be done in 6-8 weeks to ensure the dosage is correct.

Vitamin D

You may be prescribed a Vitamin D supplement like Calcitrol (Rocaltrol) to help with calcium absorption on discharge also.

When to Notify Our Office

You should call our office at 410-328-6187 if you experience the following symptoms:

  • Fever with a temperature higher than 101.5.
  • Difficulty swallowing
  • Increase in pain at the incision that is not relieved by pain medication
  • Increased swelling, redness, or drainage from the incision
  • Numbness or tingling of fingers, toes, or around the mouth.
  • Muscle cramps

Call our office at 410-328-6187. If you have trouble breathing, call 911 immediately.

Follow-Up Visit

Your post-operative appointment will be scheduled for 1 or 2 weeks after your surgery. Please call 410-328-6187 to make your appointment.

More Information

For more information, please call our office at 410-328-6187.

The Low Iodine Diet for Thyroid Cancer Diagnosis

  • By Deanna Segrave-Daly
  • In 2018
  • January 24, 2018

The Low Iodine Diet for Thyroid Cancer Diagnosis

by Zachari Breeding, MS, RDN, LDN, FAND

Thyroid Cancer is a type of cancer usually found in women (3 out of every 4 diagnoses compared to men) and is commonly diagnosed at a younger age than other adult cancers. Though mortality remains steady and low compared to other types of cancers, living with a partial or lack of thyroid tissue carries its own innate health concerns.

Most cases of thyroid cancer are known as papillary or mixed papillary-follicular subtype. The naming of these types has to do with the location of the cancer cells. Prognosis for these types are positive, with little risk of spreading to other areas of the body. When caught and treated early enough, lymph tissue is usually unaffected as well. Treatment typically includes a partial or total thyroidectomy and treatment with thyroid replacement therapy.

A partial or total thyroid resection (or thyroidectomy) may be performed if a person suffers from goiter, thyroid cancer, or hyperthyroidism. Because the thyroid gland produces hormones that regulate your metabolism, its removal can make it difficult to attain a healthy weight. Specifically, during initial management of thyroid replacement therapy (i.e. levothyroxine), weight and other nutrition markers can fluctuate. If there is little to no thyroid tissue left after resection, certain nutrition markers should receive extra attention. Of most note are calcium and vitamin D due to increased risk of hypocalcemia (from chronic hypothyroidism) and bone loss (from chronic hyperthyroidism). Because the body is no longer able to produce thyroid hormones post thyroidectomy, they run the risk of being chronically hypothyroid. This could also be related to inadequate management of levothyroxine or from endocrinologists’ recommendations to keep thyroid hormone slightly low to prevent regrowth of tissue. Furthermore, hyperthyroidism could also occur due to inadequate management of levothyroxine and poor adherence to follow-up protocol; if left untreated, osteoporosis could occur.

Regardless of how much thyroid tissue is removed, interventions for papillary or follicular types usually include radioactive iodine treatment. During this treatment, a low iodine diet is recommended for the 14 days prior to treatment. When less than 50 micrograms of iodine are consumed daily (standard for the low iodine diet), the thyroid tissue cells (including thyroid cancer cells) become “starved” for iodine. Thus, when the radioactive iodine is administered, these cells are more likely to be destroyed at a higher rate than without adherence to the diet regimen.

The low iodine diet is one that most dietitians are not educated on, since the prevalence of thyroid cancer is relatively low and is typically monitored closely by an endocrinologist. As the multidisciplinary approach to care becomes more popular, however, it is essential for the dietitian to be aware of the specifics of this dietary protocol. Of note, the most essential foods to avoid contain notable levels of iodine and include the following:

  • Cured, packaged, processed, and canned foods and meats
  • Foods containing red food dyes
  • Seafood or sea products (including seaweed, fish, carrageenan, Fish Oil, etc.)
  • Dairy products and eggs
  • Most commercial bakery products and chocolates
  • Soybeans and soy-based products; Legumes including red kidney beans, lima beans, navy and pinto beans
  • Skins of root vegetables (especially potatoes)

The recommended diet for those undergoing radioactive iodine treatment should include:

  • Kosher salt (check ingredients to ensure no iodine has been added)
  • Fresh fruits and vegetables
  • Fresh animal protein up to 6 ounces daily
  • Unsalted nuts and nut butters
  • Grains, cereals, and pasta up to 4 (1/2 cup) servings daily, provided it has no high-iodine ingredients
  • Fresh and dried herbs, spices, and vegetable oils
  • Jams, jellies, honey, real maple syrup

Zach Breeding, MS, RDN, LDN, FAND, is a Philadelphia-based registered dietitian nutritionist, professional chef and clinical dietitian at The Cancer Treatment Centers of America. He is the author of The Slice Plan: An Integrative Approach to a Healthy Lifestyle and a Better You. Connect with Zach on his website, The-Sage: Nutritious Solutions, and on Facebook and Twitter.

Is There a Diet and Fitness Plan for Thyroid Cancer?

with Anne McTiernan, MD, PhD, Neil M. Iyengar, MD, and David L. Katz, MD, MPH

Would adjusting your lifestyle reduce your risk of thyroid cancer? It’s possible. By making different choices in the way you eat and increasing your physical activity, it’s likely you can reduce your risk of cancer.1 And, even if you have been diagnosed with thyroid cancer, making these changes may improve your ability to get through treatment, recover, even lead to a better prognosis.

Getting daily physical activity is the best way to prevent cancer, and improve your prognosis after treatment for any cancer, including thyroid cancer. Photo: SDI Productions

As you may already know, the thyroid gland can have an immense effect on your metabolism, given its primary function in producing the T3 and T4 hormones. However, as relates to addressing thyroid cancer, here’s what you need to know.

In considering the potential for diet and exercise to impact thyroid cancer, there are several factors that may influence your risk of developing any type of cancer, in general, and thyroid cancer, in particular:

  • Insulin resistance is associated with a higher risk for thyroid cancer.2
  • Female hormone levels seem to play a role in thyroid cancer influence, although researchers do not understand exactly how.3
  • Excess fat is associated with an increased risk for thyroid cancer.4
  • Increased fat mass around the thyroid gland can increase your risk of thyroid cancer.4
  • Decreased muscle mass is associated with decreased recovery in some cancers.5

From the available evidence, the World Cancer Research Fund/American Institute for Cancer Research produced general recommendations to guide your approach to food and fitness so as to reduce your risk of developing many types of cancer:1

  • Eat plenty of vegetables daily
  • Choose mostly whole grains
  • Include dried beans (legumes, eg, chickpeas, lentils, edamame, black beans) for protein.
  • Limit processed meats, added sugars, and alcohol.
  • Be physically active and maintain a healthy weight.

Can we go beyond these well-known parameters for healthy living to focus on specific strategies to lower your risk of thyroid cancer? Not just yet. And, this may be fine since just achieving these parameters is a significant enough challenge for most.

Designing a diet regimen that is certain to stave off thyroid cancer, or any cancer for that matter, in every person is still a long way off. This may have more to do with the difficulty in carrying out high quality nutrition studies.

The type of studies best able to deliver clear proof of prevention necessitate randomized control trials; these are complicated and cumbersome, and not really possible when it comes to evaluating the effect that specific foods have on individuals. After all, no group of people eat exactly the same—and who would want to?!

What Would a Thyroid Diet Look Like?

Can we be more prescriptive in terms of dietary practices to prevent cancer and promote recovery following treatment? The European Prospective Investigation into Cancer and Nutrition (EPIC) Trial was a recently published cohort study that was conducted to answer this question.6

“Overall, we found little impact of vegetable or fruit intake on risk of thyroid cancer. However, we did find an increased risk of cancer in people who had large quantities of juices,” said Anne McTiernan, MD, PhD, an investigator at the Fred Hutchinson Cancer Research Center and research professor at the University of Washington Schools of Medicine and Public Health.

“This is not surprising, since people who drink a lot of juice tend to weigh more and excess weight increases risk of thyroid cancer,”7 Dr. McTiernan tells EndocrineWeb.

While the EPIC study did not detect a specific link between vegetable intake and decreased thyroid cancer risk, she believes other data exist to support this relationship. There is a pooled analysis of case-control studies of patients with thyroid cancer,8 in which the data show that higher vegetable intake provides protective properties specifically related to thyroid cancer, she says.

As well, findings from the NIH-AARP Diet and Health Study provide further support for eating vegetables regularly during adolescence as potentially increasing protection against the development of thyroid cancer.9 This is an important insight, says Dr. McTiernan, since these types of studies generally do not examine early-life diets, which is when we expect our behaviors to be more influential in the eventual formation of cancer or not.

What about the anticancer effects from eating cruciferous vegetables—does eating more of these vegetables such as broccoli, kale, cauliflower, arugula, collards, and cabbage, or have any effect on thyroid cancer? Dr. McTiernan says: “eat the broccoli, but only if you like it! All these vegetables from the cruciferous family seem to be a good and necessary addition to a healthy diet.”

Here’s the benefit to reducing your risk of cancers, including even thyroid cancer. During food preparation and in chewing antioxidant-rich vegetables, biologically active compounds—indoles and thiocyanates—are released. These food components have been studied to better understand their health-promoting (ie, anticancer, anti-inflammatory, antiviral, antibacterial) properties.

These vegetables are also a good source of dietary fiber, which you are already likely very aware, will lower your risk of chronic diseases such as heart disease, and diabetes,9,10 in addition to their antioxidant benefits.

There’s the one caveat: cruciferous vegetables contain a goitrogen, which may interfere with the absorption of thyroid hormones. This seems to be of greatest concern in individuals who have an iodine deficiency, which is not a common problem in the United States, and is lessened after cooking these vegetables. This said, this concern is of specific consequence to cancer.

So it seems that the right diet and enough exercise can reduce the risk of thyroid cancer and improve recover? The best answer is “sort of”. While there are very good general guidelines regarding diet, the experts aren’t ready to make prescriptive recommendations for you individually. That is the next step, the experts say.

This is best explained by going back to how we measure strength of the research evidence (SOE), which is essentially the methods researchers rely on to determine the trustworthiness of study results. This is what is necessary in order to have sufficient in the confidence that the data to be able to make claims like “vegetable intake can decrease your risk of thyroid cancer.”

Closer to an Anticancer Exercise Prescription, Diet is Less Clear

While there isn’t yet enough of this robust kind of evidence to describe a specific antithyroid cancer diet, the role of exercise seems a bit clearer.11

“I would bet that exercise could extend the survival rate for people with thyroid cancer,” says Neil M. Iyengar, MD, drawing on the findings from his recently published a review of the research on the potential for exercise to stop cancer.11 While the data are not definitive, Dr. Iyengar tells EndocrineWeb,” we can draw from the evidence we already have, even if not the studies were not specifically performed with thyroid cancer in mind.”

Dr. Iyengar’s bet is supported by the consensus of experts convened by the American College of Sports Medicine who endorse the strong evidence that exercise appears to reduce cancer risk by some 10-20% and improved survival for several different types of cancer.12

While thyroid cancer was not included on that list, it doesn’t rule out possible benefits for this type of cancer, too. Rather, by gaining a better understanding for the mechanisms of thyroid cancer, we can understand whether and which changes in diet and types of exercise are most likely to have a positive effect.

Even so, given the available evidence, Dr. Iyengar believes we are moving towards a future where exercise can be specific and prescriptive in improving cancer incidence and outcomes.

“If we had to choose which form of exercise would be most beneficial, it would be aerobic activities, specifically, interval training,” he says. Interval training is uniquely efficient at managing insulin, controlling inflammation and essentially creating a metabolic profile that is less susceptible to the progression of cancer, including thyroid cancer.

Ideally, resistance training should be added to everyone’s exercise routine to increase muscle density, as this has a direct effect in increasing insulin sensitivity and improving your health at the levels of cell functioning.

Interval training can also decrease fat tissue, including the adipose tissue that collects around the thyroid gland. When this occurs, it can reduce cancerous conditions by helping to regulate hormone production, namely estrogen and cortisol.

Identifying Lifestyle Patterns that Reduce Thyroid Cancer Risk

Our current methods for measuring SOE favors pharmaceutical or drug studies. We don’t have a reliable way of measuring evidence applied to lifestyle interventions, such as diet and exercise.

The American College of Lifestyle Medicine and the True Health Initiative have launched an effort to tackle this—these organizations recently developed a method to allow researchers to evaluate the evidence specifically for lifestyle interventions—Hierarchies in Evidence Applied to Lifestyle as Medicine (HEALM).12

Now, researchers like Dr. McTiernan and Dr. Iyengar will have the tools to prove their hunches and potentially prescribe specific forms of exercise and diet that could help prevent and treat specific forms of cancer.

“We know what dietary patterns best support human health, and with the right research applications, and by using techniques like those suggested by HEALM, we can begin designing lifestyle interventions to decrease the incidence of thyroid cancer and increase recovery rates,” says David L. Katz, MD, MPH, founder of the Yale-Griffin Prevention Research Center at Yale University in New Haven, Connecticut and president of the True Health Initiative.

Until then, you’re best bet is to adopt lifestyle behaviors that are not only likely reduce the risks of developing many chronic diseases including diabetes and heart disease, but also lessen your risk of developing thyroid cancer. Such a plan should feature eating mostly plants, little to no red meat, avoiding added sugars and replacing processed foods with whole grains.

If you haven’t already done so, make physical activity a part of your daily routine, and try to include exercises that boost your cardio with some interval training. Some things may be out of your control, but when it comes to lifestyle choices, you are in charge of you.

None of the experts has an financial disclosures that posed a conflict for this article. The author is an employee of True Health Initiative.

Last updated on 10/21/2019 Continue Reading Thyroid Diet: How To Eat with a Thyroid Disorder View Sources

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Thyroid Cancer: Prevention

What are the risk factors for thyroid cancer?

  • Gender: Women are about three times more likely than men to develop thyroid cancer.
  • Age: In women, thyroid cancer is usually diagnosed in their 40s and 50s. Men are usually diagnosed in their 60s and 70s.
  • Family history (genetics): Thyroid cancer can sometimes run in families. Inheriting an abnormal gene can increase the risk of developing medullary thyroid cancer.
  • Exposure to radiation: Radiation treatments to the head and neck, especially treatments during childhood, can lead to thyroid cancer. Exposure to radiation can also come from fallout from a nuclear power plant accident. Tests that use radiation to make a medical diagnosis – such as dental X-rays or mammograms – do not cause thyroid cancer.
  • History of goiter: Goiter is an enlargement (growth) of the thyroid gland.
  • Lack of iodine: Iodine is necessary to produce thyroid hormone. Thyroid cancer is more common in parts of the world where there is a lack of iodine in the diet, such as central Asia and central Africa. In the United States, iodine is present in table salt and other foods, which lowers the risk of thyroid cancer.

Can thyroid cancer be prevented?

In many cases, it is not possible to prevent thyroid cancer. However, the following might help reduce or eliminate the risk of thyroid cancer:

  • Having prophylactic (preventive) surgery: Changes in certain genes can cause an increased risk of thyroid cancer. A person might choose to have his or her thyroid removed to prevent cancer from developing there.
  • Eating a healthy diet. A diet high in fruits and vegetables and low in animal fat can reduce the risk of many types of cancer. The American Cancer Society recommends eating at least five servings of fruits and vegetables every day. Unsaturated fats (omega-3 fatty acids), especially those found in salmon and other fish, might help protect against cancer. Maintaining a healthy weight can also help protect against many diseases, including cancer of the thyroid.

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Thyroid Diet: How To Eat with a Thyroid Disorder

With Angela M. Leung, MD, MSc

“At the American Thyroid Association annual meeting, we presented in a session on Iodine and Thyroid Health, about the potential effects that dietary modifications can have on the thyroid,” says Angela M. Leung, MD, MSc, assistant clinical professor of medicine at UCLA School of Medicine in California.

Even for people with a thyroid disorder, including cruciferous vegetables should be included as part of a balanced, healthy diet. Photo: 123RF

“We summarized that adequate iodine nutrition of 150 mcg a day is essential for normal thyroid function but that an excessive intake—be it from a variety of sources (eg, fortified salt, supplements, seaweed, seafood)—can have the reverse effect: too much iodine can cause hypothyroidism and hyperthyroidism and too little iodine low may lead to hypothyroidism,” Dr. Leung says.

“It’s important to remember that you are more than your thyroid disease, so you’ll want to eat a well-balanced diet to support your overall health needs,” Dr. Leung tells EndocrineWeb. Too much, as well as too little, of any essential nutrient, may lead to more health problems, complicating your thyroid status rather than improving it.1

Understanding the Ways Diet Affects Thyroid Function

The thyroid gland is prompted to release thyroid hormones into the blood by thyroid stimulating hormone (TSH). When the thyroid doesn’t respond properly, you may develop either hypothyroidism or hyperthyroidism.

The vast majority of individuals—one in seven are women—with hypothyroidism in the US have Hashimoto’s thyroiditis, an autoimmune disease in which your body doesn’t produce enough thyroid hormone, but this isn’t caused by iodine levels in the diet.2 Other less common causes of hypothyroidism include a deficiency of iodine in the diet, taking certain medications that interfere with thyroid absorption, surgical removal of the thyroid, and a genetic disorder.

1. Focus On How to Eat Enough Vegetables, Not Which Ones to Avoid

“We talked about eating cruciferous vegetables like kale, broccoli, cauliflower, bok choy, which may have the effect of depleting the thyroid of getting enough iodine,” says Dr. Leung. Any issue with iodine update may be due to the presence of thiocyanates in this food group.

Eating too much of these vegetables could be a problem for people who don’t get enough dietary iodine and too little selenium since a lack of both of these minerals can increase the risk of forming goiters.2

And yet, the level of thiocyanates varies substantially, even in different varieties of a single food. Take kale, the level of thiocyanates in a serving can vary from zero to 400 mm/kg based on fresh vegetable weight .3

If you have hypothyroidism or a family history of goiters, you can reduce your risk by mixing up your choice of vegetables so you aren’t eating a lot of the same vegetable day in and day out, cooking your vegetables and chewing them thoroughly which helps to break down the worrisome substances, says Dr. Leung. And, it wouldn’t hurt to avoiding eating cruciferous vegetables raw; even lightly steaming then will deactivate the thiocyanates enough to assure that you aren’t eating more than your thyroid can handle.3

Another reason to lessen your concerns about these so-called goitrogenic foods is that the thiocyanate levels vary even by the type of kale, for example, for which there are more than a dozen varieties.4

The amount in broccoli, cabbage, and kale in a usual diet is considered of minimal risk. For example, there was no adverse effect on thyroid function from consuming five ounces of cooked Brussels sprouts every day for four weeks.5,6 One note of caution, if you have a thyroid disorder, it’s important to realize that juicing concentrates the amount of thiocyanate, on the order of 2000 mcg per glass.7

To offer some perspective: up to 95% of the thyroid hypothyroidism in the US is caused not by an iodine deficiency, but occurs as the result of an autoimmune disease so avoiding cruciferous vegetables will do little to fix your underactive thyroid, and may deprive you of valuable healthy benefits such as dietary fiber, and anti-inflammatory, cancer-fighting antioxidants.5

If that’s not enough to calm your concerns, some experts suggest that eating cruciferous vegetables may actually be beneficial if you have autoimmune hypothyroidism since the thiocyanates may slow the absorption of iodine in people getting too much, which is possible if you are eating a typical Western diet of fast foods, French fries, and other processed products, that contain iodized salt, and you are heavy-handed with the salt shaker.

A Quick Comment About Soy

The isoflavones in soy-based foods (eg, tofu, soy milk and soy protein, tempeh, edamame, miso) can inhibit thyroid peroxidase (TPO), an enzyme involved in the production of thyroid hormones.8

When an autoimmune thyroid disease such as Hashimoto’s thyroiditis or Graves’ disease is suspected, your doctor may do a TPO test to check for antibodies, which will help in diagnosing the reason for your thyroid disorder.

“Eating too much of these types of foods might lead to a depleted thyroid hormone level, but the chance of this happening, or the likelihood that most people will reach a dangerously high intake that would present a problem, is likely very low,” Dr. Leung tells EndocrineWeb.

2. Resist the Temptation to Follow Headlining Diets

Do yourself a favor, “resist the temptation to jump on the bandwagon of popular, headlining diets like the Leaky Gut, Gluten-Free, or Paleo,1 says Dr. Leung.

Risks may arise when you eliminate whole food groups, or worry about avoiding specific foods (ie, soy, cruciferous veggies, gluten) is not the answer to thyroid health. It’s far more important that you focus on eating for your general well-being rather than following a diet that won’t necessarily support a healthy thyroid.

“In the absence of strong scientific data supporting the association of most of these popular diets with thyroid disease, patients should be reassured that eating a well-rounded, balanced diet, and avoiding any unnecessary dietary restrictions offers the best strategy for overall health,” she says.

3. Consider Nutritional Supplements a Cautious Last Resort

While you might think you are doing the right thing by taking a nutritional supplement, the bitter truth is you may be setting yourself for unknown harms instead.

“It is difficult to recommend supplements labeled for the purpose of promoting thyroid support since these may contain nutrients in high amounts, which actually could be harmful to the thyroid,” Dr. Leung says.

There are two exceptions:

  • “In mild Graves’ eye disease supplementation with selenium is recommended,” says Dr. Leung.
  • “For women who may become pregnant, during pregnancy, or lactating, the American Thyroid Association recommends taking a daily supplement containing 150 mcg of iodine,”8 says Elizabeth Pearce, MD, MSc, professor of medicine at Boston University School of Medicine in Massachusetts, and the ATA also recommends against taking added selenium during pregnancy given some concern that there is an increased risk of developing gestational diabetes.

It’s just as important to be certain that you aren’t getting too much iodide as not getting enough. The most effective way to protect yourself is to check the label of any supplement before you take it so you are fully aware of the nutrient levels promised.

Since nutritional supplements are not regulated to the same stringent level as medications, you’ll also want to find a trusted source for any supplement you do take, so you can have some certainty of what you are getting, as you want to avoid any unnecessary or undesirable filler ingredients. For more on this read this EndocrineWeb article: Thyroid Supplements.

4. Finding the Dietary Rhythm that is Right for You

In effect, there is no single, specific diet or vitamin/mineral supplement that has been proven to eliminate thyroid disease, according to the National Center for Complementary and Alternative Medicine. If you would like more guidance on the right diet to meet your individual needs, you can consider working with a registered dietitian who has a specialty in thyroid health, or an integrative medicine physician.

The main message from this session is that having a well-rounded, balanced diet that contains hopefully at least 150 mcg of iodine per day, especially those with dietary restrictions, such as vegans and ovolactovegetarians, is recommended.1

However, there is little scientific evidence regarding some of the other dietary modifications that have been proposed and are widely popular on the internet, and these include taking extra iron and avoiding cruciferous vegetables,” Dr. Leung tells EndocrineWeb.

Updated on: 10/31/18 Continue Reading 5 Things to Do If Your Thyroid Hormone Medication Isn’t Working

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