What Causes Constipation?

Constipation is one of the most common digestive problems in Australia. It is characterised by passing hard, lumpy stools and can be classified as temporary or chronic. Suffering from constipation also means that you’re defecating less often than you normally would in a week or you’re unable to empty your bowel completely. Knowing what causes constipation will help you to effectively minimise your risk for this condition.

It can be difficult to determine the exact cause of your constipation since many factors contribute to its development. These include genetic predisposition, hormonal imbalance, pelvic floor disorders, neurological disorders, systemic conditions, or adverse side effects of certain drugs on the digestive tract. Often, a change in your lifestyle habits, such as shifting to a poor diet or having a sudden lack of mobility can also cause this condition.

Below are the common causes of constipation, listed in no particular order.

1. Low Fibre and Fluid Intake

A diet that is low in fibre and fluid consumption yet high in fats can cause constipation.

Fibre absorbs water and adds bulk to your stools, causing them to be softer and easier to pass. When you start a high-fibre diet, though, you might experience some side effects that can make your constipation worse and trigger bloating and stomach pain. But do not fret as these side effects usually go away within four weeks.

The key is to increase your fibre intake gradually. We recommend eating about 25g to 30g of fibre per day. Here are some nutritional guidelines to help you improve your diet and fibre consumption:

  • Eat 3 meals every day. Do not skip meals.
  • Select 100% whole-grain products.
  • Include rice, raw fruits and vegetables in your diet. We also recommend eating edible peels of certain fruits and vegetables, such as apple, cucumber, pears, berries, kiwi, grapes, potatoes, carrots, eggplant, and plums.
  • When grocery shopping, read the product labels and look for the term “dietary fibre”. Excellent sources of dietary fibre contain about 2g or more.
  • Drink 6 to 8 glasses of water daily. Add 2 glasses more if you consume foods high in sodium and fats.
  • Limit your consumption of processed foods.

2. Lack of Exercise

Many studies have shown that people who exercise regularly do not develop constipation. Physical activities like walking or biking for at least 4 hours per week can also likely lower your risk of developing colorectal cancer. These activities have a protective effect on your colon as they can help restore energy balance and improve gastrointestinal transit time.

Furthermore, a good abdominal muscle tone can also keep you regular. If your abdominal muscles are weak, they cannot effectively move your stool out of your colon and through your rectum for elimination. Stools that remain in your colon for too long will harden and thus lead to constipation.

To improve your bowel movement, we advise exercising every day. It can be as simple as walking for 30 minutes daily or just move around your house every 3 hours or so during the day. Lastly, do not ignore your urge to pass stools to prevent constipation.

3. Opioids and Other Medications

Opioids are substances that bind to receptors in your brain and body. These receptors are associated with impulsive-addictive behaviours, pain, and reward. In the treatment of moderate to severe pain in cancer patients, opioids are used to block pain signals between the brain and body. However, one of its downsides is constipation. In some patients, opioids may also trigger bloating, nausea, stomach pain, or vomiting.

Opioid-induced constipation is common. It affects 40% to 60% of non-cancer patients who are receiving opioids and 94% of cancer patients taking opioids for pain. Many patients who develop opioid-induced constipation quit this type of drug therapy because they cannot tolerate its side effects on their gastrointestinal tract.

Constipation can also occur as a side effect of some prescription and over-the-counter medications. Examples include anticholinergics, antispasmodics, bismuth salts, antidepressants, anticonvulsants, diuretics, antacids, calcium-channel blockers, tranquillizers, and sedatives.

If you think the drug you’re taking is causing your constipation, consult your physician. Do not immediately stop your drug without the advise of your doctor. Good lifestyle habits, such as keeping yourself hydrated, increasing your fibre intake and exercising 30 minutes each day can also help prevent your constipation from coming back.

4. Overuse of Laxatives

Laxatives are substances that help stimulate the nerves in your large intestine. This process contracts your intestinal muscles and pushes your stool to move out of your colon. However, when used for an extended period of time and at high doses, they can damage those nerves in your gut. This can lead to dehydration, electrolyte imbalances, and nutritional deficiencies, thereby causing your constipation to worsen over time.

Keeping your stomach empty can also disrupt your normal digestive process. When you prevent your intestinal muscles from working as they should, whether by using laxatives, inducing vomiting, or skipping meals, they lose their strength over time which may cause constipation.

And if you’re suffering from bulimia or anorexia nervosa, you may also become dependent on laxatives as a way to empty your stomach. In this case, we recommend consulting your doctor to help you deal with your eating disorder properly.

Conversely, some individuals with chronic constipation may find that the long term use of laxatives is an effective solution. We fortunately now have bulk-forming laxatives, also known as fibre supplements like Citrucel and Metamucil that are safe to use long term. Make sure you get your physician’s approval first if you’re planning to use laxatives for your chronic constipation.

5. Specific Foods

While there are foods that can help prevent or relieve constipation (e.g., prunes, apples, and oatmeal), some tend to have the opposite effect, especially when consumed in large amounts. These include milk and dairy products, processed grains, fried foods, unripe bananas, persimmons, and gluten (e.g., wheat, rye, and barley). Other foods that can contribute to sluggish bowel movements are red meat (low in fibre and high in fats) and alcoholic drinks.

6. A Symptom of a Digestive Condition

Constipation can also be a sign of an underlying disease or certain food intolerances. For example, individuals who suffer from milk protein intolerance lack the enzymes necessary to digest casein and whey proteins. This eventually causes their stool to become hard and difficult to expel.

If you think that your constipation is a result of a more serious disease, see your trusted healthcare provider for a more accurate diagnosis and treatment plan. You may be asked to make some dietary changes to help manage your symptoms.

Make Changes to Manage Your Constipation

Constipation is a common digestive issue that can usually be resolved by making changes to your diet and lifestyle.

Start by increasing your daily fibre and fluid intake, but be wary of certain foods that can trigger the symptoms of your underlying digestive problem, if there’s any. Exercise regularly to improve your bowel movement. Lastly, do not abuse laxatives or other medications to avoid causing damage to your gastrointestinal nerves. If none of these work, consult your physician immediately.

Need Our Help?

Schedule an appointment with an accredited dietitian or nutritionist by phone on (07) 3071-7405 between 8am and 6pm Monday to Friday or send us an enquiry. Alternatively, you may want to try these six home remedies for constipation.

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