In this article:
- Common causes of constipation
- How to relieve hypothyroidism-related constipation
The thyroid is the butterfly-shaped gland at the base of your neck that helps to regulate the body’s metabolism in the form of blood pressure, blood temperature, and heart rate. When your thyroid hormone production drops, your body processes slow down and change, affecting virtually all aspects of your health.
Indeed, your thyroid regulates every system in your body, so it comes as no surprise your digestive system also suffers when your thyroid hormone production drops. Constipation is one of the most common symptoms of hypothyroidism, and trying to find a solution can be challenging.
Constipation is defined as having three or fewer bowel movements in one week or having painful or unproductive bowel movements. Bowel function varies widely from person to person, so it is essential to know what is normal for you to figure out when your bowel habits are not as expected.
Other than the frequency of bowel movements, additional criteria used to define constipation include symptoms like:
- Dry or hard stools
- Painful or difficult-to-pass bowel movements
- A feeling that you have not fully emptied your bowels
What are the causes of constipation?
As food moves through the digestive tract, nutrients are absorbed. The waste then moves from the small intestine to the large intestine (the colon). The colon absorbs water from the waste, creating a solid matter called stool. Constipation happens when your colon absorbs too much water from the waste, which dries out the stool, making it hard in consistency and difficult to eliminate from the body.
In addition to hypothyroidism, other causes of constipation may include:
- Not eating enough fiber
- Not drinking enough liquids
- Physical inactivity, especially in the elderly
- Some medications or supplements
- Overuse of laxatives
- Ignoring the urge to have a bowel movement
- Specific medical diseases or conditions
How to relieve hypothyroidism-related constipation
Treat your thyroid
The best way to treat hypothyroidism-related constipation is to start by treating your thyroid with thyroid hormone replacement medication. Low thyroid hormone levels (T4 and T3) slow all of your body systems, including gastric motility, leading to constipation. Thyroid medication replaces the thyroid hormones that your thyroid gland fails to produce.
The majority of people with hypothyroidism need to take thyroid hormone replacement medication for the rest of their life. It can take some time to find the correct type and dose for you, but once you do, you can expect to see improvements in your thyroid symptoms, including your bowel habits.
Suppose you are still experiencing constipation after you have been on your optimal dose of thyroid medication. In that case, you need to explore some other factors that may be affecting your bowel habits.
Consider your diet
Whether you have hypothyroidism or not, diet plays a significant role in your bowel function. Certain foods can speed up gastric motility, whereas others can slow it down.
Fiber is one of the critical nutrients you need to consider when aiming to regulate your bowels. There are two different types of fiber:
Insoluble fiber helps stool quickly pass through your intestines. You can find insoluble fiber in the peels of fruits and vegetables, whole grains, and wheat bran.
Soluble fiber pulls water into your stool and slows down the digestive process. However, the stool is softer because it contains more water so that it can pass easier. You can find soluble fiber in some fruits and vegetables, legumes, seeds, and oat bran.
The best way to get fiber is through your diet. Foods high in fiber include:
- Chickpeas, edamame, lentils, and split peas
- Whole wheat food, including pasta
- Berries (especially raspberries and blackberries
- Brussels sprouts
- Artichoke hearts
If you are starting to add more fiber to your diet, do so slowly, as increasing your fiber all at once can make you feel bloated.
People with hypothyroidism need to be cautious of overeating fiber, mainly because the fiber in your diet or fiber supplements may affect the absorption of your thyroid medication. We recommend that you take your thyroid medication first thing in the morning and then wait several hours before eating or taking any other medications or supplements to allow proper absorption.
To make sure you are getting an appropriate amount of fiber, talk with your thyroid nutritionist to develop a meal plan specifically tailored to the needs of your thyroid and your gut.
Drink plenty of water
Water is crucial for helping stool pass easily. If there is not enough water in your stool, it can slow its progress through your system and becomes painful. People who add more fiber to their diet also need to increase their water intake, as soluble fibers pull water into digestive contents. Most sources recommend you drink between 6-8 glasses of water per day unless you have a condition where you should restrict fluid intake, like kidney or heart disease.
Increase your physical activity
Exercise is an integral part of everyone’s bowel regimen. Regular exercise keeps contents moving throughout your digestive system. When you become sedentary, it takes more time for stool to pass through your intestines. Consequently, water gets reabsorbed into your body. Therefore, stools harden and become more challenging to expel.
Sometimes, people need to go through bowel retraining, which usually entails boosting their physical activity, strengthening pelvic muscles with exercises like Kegels, and learning biofeedback (a behavioral approach that can help you gain control over involuntary bodily functions) to treat constipation.
Use a laxative when needed
Over-the-counter (OTC) laxatives are generally safe to use here and there. Sometimes, it takes a few doses of a laxative or even a few weeks of regular dosing to help get your bowel back on track. There are several types of OTC laxatives:
- Bulking agents - these contain fiber and add “bulk” and fluid to your stool to make it easier to pass
- Osmotic agents - help you keep water in your stool so that it is softer (milk of magnesia and Miralax® are examples of this type of laxative)
- Lubricants - coat the outside of the stool in fluid or oil
- Stool softeners - also bring water into the stool and help you not feel like you have to strain
- Stimulant laxatives - these medications “stimulate” the intestines to contract so that stool can pass more quickly
The American Gastroenterological Association recommends you talk with your doctor about what type of laxative to use, especially if this is a reoccurring problem. Sometimes, people can get into a vicious cycle where they use too many laxatives and have diarrhea, followed by rebound constipation.
A note from Paloma Health
Constipation is a common symptom of hypothyroidism. If you are struggling with this issue, it may help to check your thyroid hormone levels. For people with hypothyroidism looking for more solutions to manage their constipation, talk with your thyroid doctor about how to best regulate your bowel habits.