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Is Coffee Harming Your Thyroid?

Is Coffee Harming Your Thyroid?

Coffee has become exceptionally prolific throughout the United States. For many, the addictive and energizing beverage is an essential part of their morning routine. Most regard this habit as harmless. However, thyroid patients who drink coffee may be inadvertently harming their health. To avoid thyroid disruption, it is essential that thyroid patients be aware of the impact of coffee on the thyroid.

What Is the Thyroid Gland?

The thyroid is a small butterfly-shaped gland located in the neck. The powerful gland influences virtually every bodily process. This is done through the production of various hormones including thyroxine (T4), triiodothyronine (T3), reverse triiodothyronine (RT3), and others. Some of the processes most dependent on healthy thyroid activity are weight management, growth, metabolic activity, and temperature regulation. Because of its broad influence, any form of thyroid disruption can quickly escalate into system-wide dysfunction. 

Learn more about the thyroid gland here.

When functioning properly, the thyroid produces T4, the storage form of thyroid hormone, to later be converted into T3. T3 is the active form of thyroid hormone, which accelerates cellular activity. T4 may also be converted into RT3 which reduces the efficacy of T3 thereby decreasing cellular activity. To maintain healthy bodily function, T4, T3, RT3 and other hormones such as insulin, cortisol, and sex-hormones must be maintained at the appropriate values. An imbalance of one or more of these elements can result in thyroidal disruption which can cascade into greater dysfunction. 

Despite many people being unfamiliar with thyroid disease, thyroid-related dysfunction is actually quite common. Some studies estimate that there are over 27 million cases of thyroid dysfunction among adults in the United States and over 60 million worldwide. The most common form of thyroid dysfunction is hypothyroidism, which involves a decline in thyroid function resulting in widespread slowing of bodily function. Some of the most common symptoms of hypothyroidism include fatigue, weight gain, hypoglycemia, difficulty thinking clearly, and in some cases depression – get a full list of thyroid disease symptoms here.

How Coffee and Caffeine can Disrupt the Thyroid

There are many things that may cause the thyroid to become dysregulated. One that is frequently overlooked is the consumption of coffee. Thyroid patients must be careful when drinking coffee. Poor timing and drinking too much coffee can encourage thyroid dysfunction by influencing various factors of wellness. Coffee may negatively impact adrenal function, sleep quality, intestinal activity, hormone balance, and absorption rates of thyroid medication. All of these elements are important for maintaining healthy thyroid activity. 

Coffee Triggers Blood Sugar Spikes and May Encourage Adrenal Fatigue

Many thyroid patients struggle with maintaining balanced blood sugar levels. Drinking caffeinated beverages such as coffee can exacerbate this issue. Studies show that caffeine significantly increases blood sugar, which can trigger the body’s stress response and prompt the release of cortisol. These factors con contribute to or trigger flare ups of hypoglycemia, Hashimoto’s thyroiditis, and adrenal fatigue. Worse still, the resulting crash following the blood sugar spike can trigger the release of additional cortisol, which further promotes adrenal fatigue and thyroid malfunction. 

Learn more about the connection between the thyroid and the adrenals here.

Coffee Can Reduce Sleep Quality

Caffeine consumed late in the day or at night can impede sleep and reduce sleep quality. Drinking coffee triggers the body’s stress response which may cause the drinker to feel wired, fidgety, or restless. These qualities can significantly reduce sleep quality and limit your ability to fall asleep. Poor sleep quality compounds the effects of stress which can disrupt the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis plays a direct role in the regulation of thyroid activity. Therefore, disruption of the HPA frequently leads to thyroid malfunction. 

Coffee Often Promotes Intestinal Issues

Regularly ingesting acidic substances like coffee can irritate important regions of the intestinal tract. This not only causes discomfort but may contribute to intestinal malfunction. The acidic nature of coffee promotes the release of gastrin and bile, which can compromise the intestinal lining of those with autoimmune conditions. Because the gut is closely related to thyroid function and overall wellness, intestinal issues can trigger thyroid malfunction or worsen already extant thyroid issues.

Coffee May Encourage Hormonal Imbalances

Studies show that women who regularly consume large amounts of caffeine in one sitting (at least 500mg or the equivalent to 5 cups of coffee) are far more likely to experience estrogen dominance, which may contribute to thyroid dysfunction. Estrogen is an important hormone in both men and women. If estrogen levels increase and become imbalanced with other hormones, various issues can develop including inhibited conversion of T4 to T3. Poor conversion of thyroid hormones is a common contributor to hypothyroidism.

Coffee Impedes Absorption of Thyroid Medication

Perhaps the greatest problem with coffee, regarding thyroid activity, is that it impedes the absorption of thyroid medication. Studies have repeatedly shown that drinking coffee negatively affects the absorption rate thyroid medications. Drinking coffee in close proximity to taking your dose may negate virtually all the benefits of the medication. For this reason, thyroid patients should wait at least one hour, some experts say up to three or four hours, after taking their medication before drinking coffee or other caffeinated beverages. Appropriately timing your thyroid medication and morning coffee may significantly improve the efficacy of the treatment. 

Can I Still Drink Coffee If I Have a Thyroid Condition?

Although it is not necessary for thyroid patients to remove coffee from their diet entirely, patients who do so tend to report better sleep, fewer headaches, less anxiety, and a decrease in hypothyroid and digestive issues. Even a temporary refrain from coffee can give the body time to stabilize and reduce the occurrence or intensity of symptoms. Regardless if you decide to cut out coffee completely or simply take a break; it is essential that coffee be avoided for at least one hour after taking thyroid hormone replacement medications. As long as appropriate timing for medication and coffee intake is maintained, thyroid patients can safely enjoy coffee.

Adopt Healthy Coffee Habits to Protect Your Thyroid

Many thyroid patients unwittingly sabotage the efficacy of their medications by drinking too much coffee or by drinking it too soon after taking their medication. Possible outcomes of poor coffee drinking habits include blood sugar crashes, sleep disruptions, intestinal stress, hormone imbalances, and absorption issues. Fortunately, it may be possible to avoid these thyroid-disrupting problems by wisely timing your medication and monitoring your coffee intake. 


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