How to Spot, Avoid, and Manage Hashimoto’s Flare-Ups

Jessica Migala
Medically Reviewed
July 1, 2020

Hashimoto’s causes a low functioning thyroid, creating a cascade of symptoms that can be triggered at any time. Adding to the fire: it’s an autoimmune condition, meaning each flare damages the ever-important gland.

What is Hashimoto’s disease? This autoimmune condition is what happens when your own immune system makes antibodies that attack and damage your thyroid, which is the butterfly-shaped gland at the base of your neck. About five percent of people have Hashimoto’s disease, and it affects 8 times more women than men, most often between ages 40 and 60, according to the National Institute of Diabetes and Digestive and Kidney Diseases . Hashimoto's disease symptoms vary from person to person.

The autoimmune condition is a primary cause of hypothyroidism , which means your thyroid hormones are low . Thyroid hormones are essential for regulating your metabolism, body temp, heart rate, energy, menstrual cycle, mood, and hair and nail growth. When these hormones are out of whack, your body is, too. If you're wondering, "Does Hashimoto's cause headaches?", research has shown that once hypothyroidism has developed, migraines and headaches can become more frequent and severe. You may also feel fatigue, gain weight, be perpetually cold, experience constipation, have fertility issues, brain fog, or have aching joints and muscles, all of which are symptoms of Hashimoto’s. (Thyroid hormone levels can also be too high, a condition called hyperthyroidism, which may be caused by Grave’s disease.)

But these symptoms can be vague. It’s easy to chalk them up to stressful weeks or lack of sleep, so you may not even notice there’s a problem at first. “Many people don’t know they have Hashimoto’s,” says Neeti Sharma, MD, formerly a board-certified internal medicine physician at Parsley Health . “They may know they have hypothyroidism, but doctor’s offices don’t frequently check for antibodies that signal an autoimmune condition,” she explains. While it’s not entirely clear why people develop autoimmune conditions, Dr. Sharma says that it’s likely that you have a genetic predisposition to autoimmunity that’s activated by something in the environment. “Your immune system goes into dysfunction when the body is not in a healthy environment, and your thyroid tends to be the system that’s most responsive when things are off.”

Knowing if you have these antibodies—something that can be done with a simple blood test —is essential because Hashimoto’s is a progressive disease. These antibodies will eventually damage and destroy your thyroid gland, even if symptoms of Hashimoto’s disease are not present now, says Dr. Sharma. Along with ongoing inflammation, that damage will impair the functioning of your thyroid gland so that it cannot make the hormones needed to keep you feeling well. “It helps to know if you have it so that you can do something about it early on and avoid the specific triggers that cause a flare,” she says.

What is an autoimmune flare-up?

A flare-up can happen in any autoimmune disease, and it means that symptoms suddenly and swiftly return , and while they look like the symptoms you normally experience, they tend to be more severe in a flare. Just as you’ve been coasting along and feeling pretty great, you’re hit again with familiar symptoms. You haven’t pooped in days . You’re wearing your “summer sweaters,” you’re mopey as heck, and no number of naps can relieve the unrelenting fatigue. Flares happen because there’s additional stress on your body, which taxes an immune system that already acts unnaturally hyper vigilant, sending it into a tailspin. “When flares happen, there is a greater antibody response going on at that time, which leads to more destruction of the thyroid gland,” says Dr. Sharma.

What are the symptoms of Hashimoto’s disease?

  • Fatigue
  • Cold intolerance
  • Constipation
  • Dry skin
  • Puffy face
  • Muscle aches
  • Brain fog
  • Insomnia
  • Low mood or depression
  • Irregular or heavy periods
  • Enlarged thyroid gland (this is called a goiter)

Also be aware that it’s possible that a Hashimoto’s flare-up could actually cause your body to go into a hyperthyroid state, which means your thyroid is overactive. “With the destruction of thyroid cells, the gland releases thyroid hormones quickly into the bloodstream,” says Dr. Sharma. In that case, you can actually experience symptoms of hyperthyroidism , like:

  • Fatigue
  • Heat intolerance
  • Irritability
  • Rapid heartbeat
  • Sleep problems
  • Anxiety

What is a Hashimoto’s flare-up?

So, what does a Hashimoto's attack feel like? Not every person with Hashimoto’s will have the same triggers. “Each individual will have a unique immune system that responds differently to the environment. There is no one-size-fits-all when it comes to triggers,” explains Dr. Sharma. However, there are some common lifestyle factors that may precede a flare and they fit in several larger buckets: diet, lifestyle, environmental, and medical. Knowing what they are can help you pinpoint the ones that are true to you:

Your diet: According to Dr. Sharma, many people find that grains (specifically gluten -containing grains, like wheat, barley, or rye), high sodium intake, as well as high iodine intake are common triggers for a Hashimoto’s flare-up. Table salt is traditionally iodized, so if you’re eating a lot of high-salt foods you’re also likely consuming too much iodine.

Your lifestyle: Lack of sleep or insomnia, high levels of stress, as well as being too sedentary—or conversely—overtraining with high-intensity exercise are triggers for flare-ups.

The environment: Studies show that chemicals in plastics like bisphenol A (BPA), pesticide exposure, and air pollution, can disrupt thyroid function.

Medical: These may include pathogens. “Helicobacter pylori (H. pylori), is the bacteria that causes stomach ulcers, and is an unrecognized Hashimoto’s trigger in patients,” says Dr. Sharma. An illness can also trigger the disease, as can hormonal fluctuations, which is one reason why the disease may disproportionately affect women.

What is Hashimoto’s disease treatment?

You’ll want to work with a doctor who can spend time with you to find what sets off your Hashimoto’s disease. “We have to figure out each individual’s reason for why they have these autoimmune antibodies in the first place,” says Dr. Sharma. Identify what might have happened in your life to lead to the flare, and then hone in on those factors to better manage symptoms throughout a flare—and help you feel your best. These are some ways Parsley Health’s doctors work with members to help them manage increased antibody formation and inflammation that leads to flares.

Address your stress.

We all have stress, but when you have Hashimoto’s, it’s important to guard your time, give yourself some grace on your to-dos, and relax when you need it. It’s also important to realize that an overload of mental stress isn’t just a trigger for a flare itself, but can also impact your ability to care for yourself as you otherwise would, says Dr. Sharma. For instance, if you’re under stress, you might reach for less healthy foods or might be going to bed later or staying up late with worry and anxiety. Now is the time to go full-stop with self-care: unplugging when you need to/temporarily deleting social media apps, going to bed early, calling a friend to vent, and taking walks outside if you have the energy.

Check your supplements.

Is your body getting what it needs to fully support thyroid function? “We want to make sure that you’re supplemented enough with selenium and vitamin D in particular. You need all of the building blocks it takes to make thyroid hormone so that you’re not going into a hypothyroid state because of nutritional deficiencies,” says Dr. Sharma.

Eat fresh, whole foods.

Inflammation increases the autoimmune reaction, so focus on eating an anti-inflammatory diet, says Dr. Sharma. “Focus on non-processed foods, lots of vegetables and greens, organic meats, and reduce sugar intake,” she advises. Eat more dark leafy greens, which pack a powerful antioxidant called glutathione to help reduce inflammation, she says.

Ditch sugar and gluten.

Cookies and ice cream may be comforting in times of stress, but they’ll only exacerbate your symptoms now. Loading up your diet with sugar will lead to spikes and dips in blood sugar, something that activates your immune system, says Dr. Sharma. Since gluten is a trigger for many people, consider avoiding gluten-containing foods (many packaged snacks, wheat pastas, bread, cereal, and junk foods).

Watch your iodine.

Iodine is a mineral that your thyroid uses to make thyroid hormones. However, a high iodine intake, which can come from too much table salt (in the form of processed, packaged foods) will negatively affect thyroid functioning, says Dr. Sharma. She recommends sticking to a low iodine diet during Hashimoto’s flare-ups.

Jessica Migala

Jessica Migala is a health and medical freelance writer living in the Chicago suburbs. She's written for publications like Women's Health, Health, AARP, Eating Well, Everyday Health, and Diabetic Living. Jessica has two young, very active boys.

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