Your thyroid is a small butterfly-shaped gland at the base of your neck that regulates the release of hormones and regulates your metabolism. When your thyroid hormone production drops, your body processes slow down and change, affecting virtually every system in the body.
You can take an at-home thyroid blood test to understand how your thyroid is functioning. Many labs only look at thyroid-stimulating hormone (TSH). Still, we believe it's important also to measure free triiodothyronine (fT3), free thyroxine (fT4), and TPO antibodies to understand the big picture and where specifically to make improvements.
Should your results show that your thyroid is underactive, it is treatable with thyroid hormone replacement medication. Beyond taking thyroid hormones, you can support your thyroid with nutrition and self-care.
Just as it's essential to eat a nutrient-dense diet, it's also important to understand what foods to avoid if you have a thyroid condition. Some foods may cause inflammation that can worsen your autoimmune reactions or interfere with your thyroid function.
Dietary triggers can lead to increased gastrointestinal permeability, chronic inflammation, and a possible elevation in thyroid antibodies. Of course, what is a trigger for you may not be a trigger for someone else with the same condition. Understanding your dietary triggers helps you to create a personalized diet plan for your hypothyroidism.
What foods to avoid with hypothyroidism or Hashimoto's
Sugar & additives
Additives like gums, food dyes, and sugars do not promote healing. First, let's look at the different types of sugar.
Sucrose is what you'd call "table sugar." Commonly extracted from cane sugar or sugar beets, it's found naturally in various fruits, veggies, and grains, as well as many processed foods.
Sometimes referred to as "fruit sugar," fructose is derived from fruit. Fructose also comes from honey, agave, and most root vegetables. Like sucrose, it is in many processed foods in the form of high-fructose corn syrup.
Glucose is the term for blood sugar. It's your body's preferred carb-based energy source because it converts quickly and easily into energy.
There are over 60 different names for sugar! Some are more obvious than others, like brown sugar, corn syrup, and cane sugar. Others are trickier to identify, such as Muscovado and Turbinado, which sound more like vacation destinations than sugar types.
Not all sugar is created equal. Some forms of sugar affect your blood glucose differently than others. This difference is called the glycemic index, a system that ranks foods on a scale from 1 to 100 based on their effect on blood sugar levels.
An apple has a glycemic index of about 38-43, which is a lower GI. This glycemic index is about the same as grapes, peaches, or oranges. Fruit can also be higher in fiber than many processed foods, which helps you feel fuller longer. Eating fruit is an excellent option if you're craving something sweet!
For those with hypothyroidism or Hashimoto's, it's essential to know where refined sugar might be hiding. Too much can lead to increased inflammation, blood sugar imbalances, and hormone function disruption.
Overconsumption of sugar also causes spikes in insulin which makes the adrenal gland secrete cortisol. When cortisol levels are too high, thyroid hormone production is hindered. Between increased chronic inflammation and the decreased production of thyroid hormones, sugar can leave the body dealing with frustrating symptoms.
Similarly, processed food is generally high in sugar and additives like preservatives, colorants, flavor enhancers. Our bodies cannot recognize most of these pre-packaged foods as nutrients for our body which leaves us depleted of essential vitamins and minerals our thyroid needs to function.
Everything that we eat is either helpful or hurtful, and it can take years to correct the damage from an unhealthy diet. Opting instead for whole foods from nature will help you to heal and feel better, faster.
People with Hashimoto's disease tend to have a higher sensitivity to specific proteins found in dairy products. They also tend to have a higher incidence of lactose intolerance. A recent study found lactose intolerance diagnosed in 75.9% of test patients with Hashimoto's.
If you have lactose intolerance, you may suffer from malabsorption of essential nutrients and oral medications - including your thyroid meds!
Dairy has many redeeming nutritional qualities, especially in its raw and fermented states. Many dairy products we eat today are highly processed and can wreak havoc on the digestive system or trigger inflammation for some.
Of course, not all inflammation is harmful. It's a vital part of the immune system's response to healing injuries and infections. Here, however, the type of inflammation we are talking about is chronic inflammation caused by dietary and lifestyle factors.
So, what's the difference between a dairy allergy and dairy intolerance?
A dairy intolerance (or lactose intolerance) involves your digestive system. A dairy intolerance occurs when your body doesn't produce LACTASE, the enzyme needed to digest the "milk sugar" LACTOSE. When lactose doesn't get broken down the way it should, undigested lactose ends in the colon instead of the stomach and small intestine. Dairy intolerance, while uncomfortable, is not life-threatening.
A dairy allergy, on the other hand, is triggered by your immune system. This allergy happens when your body reacts to the proteins in milk, CASEIN and WHEY, as if they're foreign invaders. Allergic reactions may include hives, wheezing, shortness of breath, stuffy nose, swelling of the lips or tongue, or increased mucus production. Like lactose, these allergenic milk proteins (casein and whey) hide in other products beyond plain dairy milk, so keep an eye on nutritional labels!
Aside from allergy testing, an elimination diet may help to determine if dairy is a dietary trigger for you. High-quality dairy may be acceptable in moderation for some people after healing their gut.
When you hear the word gluten, you might think carbohydrate—for a good reason. Many carbohydrate-rich foods, like pizza and pasta, contain gluten. However, gluten is the name for the proteins found in wheat, rye, barley, and triticale (a cross between wheat and rye). Gluten acts as a glue that helps foods to maintain their shape.
For some people with hypothyroidism or Hashimoto's thyroiditis, eating gluten can trigger adverse reactions. In the short term, gluten can cause uncomfortable symptoms like headaches, tiredness, mood swings, bloating, abdominal pain, brain fog, or even a breakout.
Over the long term, though, the effects of gluten go deeper. Some studies show that people with autoimmune thyroid disease, like Hashimoto's, may also have celiac disease.
Celiac disease is an autoimmune condition in genetically predisposed people where ingesting gluten leads to damage in the small intestine. When people with celiac disease eat gluten, their body mounts an immune response that attacks the small intestine, damaging the villi, meant to promote nutrient absorption.
Those suffering from autoimmunity also deal with some intestinal permeability—also known as leaky gut.
A leaky gut is where potentially harmful molecules, such as gluten, pass through the walls of the intestines and into the bloodstream. For some, like those with celiac disease, the immune system recognizes these molecules as foreign invaders and attacks them
Experts believe that a gluten-free diet can reduce thyroid disease complications and improve the quality and, perhaps, length of life in patients.
While a blood test can confirm an intolerance to gluten, you can also get answers by experimenting with how you feel on and off gluten.
Caffeine, a stimulant of the nervous system, is generally anti-inflammatory. Still, research finds that the effect of caffeine on immune function is quite complicated! For some people, caffeine decreases inflammation, and for others, it has the direct opposite effect.
Caffeine shows up in many everyday groceries like:
- Coffee and coffee-flavored food products
- Many teas
- Chocolate in all of its forms
- Energy drinks
- Some protein bars
- Some breakfast cereals
- Medications for PMS, headaches, and migraines
- Some common additives in foods including ginseng, malic acid, and niacin
While caffeine's effect directly on the thyroid may be highly individualized, the impact of caffeine on the adrenal glands is clear. Caffeine stimulates your adrenal glands to secrete the stress hormones epinephrine and cortisol. Excessive cortisol production can lead to various health issues like an overactive immune system, disrupted sleep, impaired digestion, or mood issues.
While it's still unclear why some people experience an anti-inflammatory effect from caffeine and other experience immune stimulations, it may be worthwhile to experiment with an elimination diet to determine if caffeine is a dietary trigger for you.
Research shows that alcohol has multiple effects on the functioning of the thyroid gland. Namely, it can cause damage to your thyroid cells and suppress thyroid hormone production. It can also weaken your immune system, cause inflammation, and damage your liver, critical to thyroid hormone conversion.
Part of the liver's job is to filter everything that enters your body, like food, drinks, and medicine. After your intestines break down things that you eat or drink into their component parts, your liver is responsible for separating the good from the bad.
Nutrients get sent into your bloodstream for your body to use, and the bad stuff gets discarded. However, a congested liver prevents your body from effectively converting the inactive thyroid hormone T4 to the active hormone T3, so it's crucial to keep it in tip-top shape.
Alcohol can also cause sleep disturbances. While you may fall asleep faster, it may be difficult to stay asleep, fall back asleep, or sleep restfully. It would be best if you aimed to get between 7-9 hours of quality sleep per night to allow your body to rest, reset, and recharge. Sleep helps to regulate other hormones like estrogen, progesterone, cortisol, melatonin, and adrenaline.
Alcohol can interfere with how the body processes estrogen. If your liver can't effectively process estrogen, it can build up in your tissues, causing estrogen dominance. Estrogen dominance can activate your body's stress response and perpetuate the cycle of stress, hormone disruption, and hypothyroid symptoms.
Like everything on this list, it may help to experiment with an elimination diet or work with a thyroid nutritionist to determine if alcohol is a dietary trigger for you.
The cruciferous vegetables myth
Belonging to the Brassicaceae family of plants, cruciferous vegetables offer lots of great benefits, including cancer-fighting properties, inflammation reduction, and healthy estrogen levels. There is a common misconception that people with hypothyroidism or Hashimoto's should avoid hearty cruciferous veggies like cauliflower, cabbage, or Brussels sprouts because they are high in goitrogens, which some people think block the intake of iodine in the thyroid gland.
The mineral iodine plays an essential role in thyroid hormone production. The truth is, those of us whose diets contain adequate iodine (which is most of us in iodine-sufficient countries like the United States) can eat these vegetables in reasonable amounts—especially when cooked.
A note from Paloma Health
You should consult with your thyroid care team before making significant changes to your diet. A thyroid nutritionist can help you identify what foods to avoid if you have hypothyroidism and develop a personalized eating plan to help you feel better, faster.