Constipation affects millions worldwide and can be more than just a temporary inconvenience, it can signal an underlying medical issue. If you’re experiencing persistent issues, it’s wise to look beyond diet and exercise. Gastroenterologists often highlight that chronic constipation is sometimes rooted in broader health concerns. Here are five medical conditions commonly linked to this issue, and how to recognise them.
- Hypothyroidism
Why it causes constipation:
An underactive thyroid slows down your metabolism, often including the digestive process. When gut motility decreases, bowel movements become infrequent or difficult. In some cases, the intestinal muscles may not contract effectively, leading to a sluggish transit of stool through the colon.
Signs to watch:
- Feeling cold frequently
- Unexplained weight gain
- Fatigue, even with adequate sleep
- Dry skin or hair
- Swelling around the neck (goiter)
Next steps:
If you spot multiple symptoms, a simple blood test measuring TSH (thyroid-stimulating hormone) levels can confirm if your thyroid is underperforming. Management typically involves hormone replacement therapy.
- Diabetes (especially diabetic neuropathy)
Why it causes constipation:
High blood glucose levels over time can damage nerves controlling the digestive tract, a condition called autonomic neuropathy. This nerve damage means your intestines may not contract properly to move stool.
Signs to watch:
- Frequently high blood sugar readings
- Numbness or tingling in hands/feet
- Feeling bloated or full even after small meals
- Slow or irregular digestion
Next steps:
If you’re diabetic and not seeing expected results from diet changes, mention persistent constipation to your doctor or gastroenterologist. Testing for autonomic neuropathy or adjusting your diabetes management plan may help.
- Parkinson’s Disease (and other neurological disorders)
Why it causes constipation:
Neurological disorders affecting the brain and nervous system can interfere with the coordination necessary for normal bowel function. Reduced neural signals slow gut motility.
Signs to watch:
- Tremors or shaking at rest
- Muscle rigidity or slowness of movement
- Frequent blanking or “freezing” episodes
- Changes in handwriting or facial expression
Next steps:
Constipation is sometimes one of the earliest symptoms of Parkinson’s, appearing long before motor symptoms. If you notice stool consistency changes along with movement issues, mention both to your neurologist and gastroenterologist.
- Irritable Bowel Syndrome with Constipation (IBS-C)
Why it causes constipation:
IBS-C is characterised by irregular intestinal movements, abdominal cramping, and bloating. Though the exact cause remains unknown, stress, hormonal changes, and the gut-brain axis are implicated.
Signs to watch:
- Alternating constipation and bloating
- Abdominal discomfort that improves after passing stool
- The feeling of incomplete evacuation
- IBS in the family history
Next steps:
Diagnosis often involves ruling out other conditions via testing, plus tracking symptoms and diet. Treatment can include fibre changes, probiotics, prescription laxatives, and stress management techniques. A gastroenterologist can tailor solutions based on your symptoms.
- Hypercalcaemia (High Blood Calcium)
Why it causes constipation:
Elevated blood calcium levels, often from an overactive parathyroid gland, excessive supplement intake, or certain cancers, can reduce neuromuscular excitability, slowing down your gut.
Signs to watch:
- Excessive thirst and frequent urination
- Muscle weakness or aching
- Confusion or fatigue
- Kidney stones or back pain
Next steps:
This is typically diagnosed via routine blood tests. If calcium is high, your doctor may order an ultrasound or scan of the parathyroid glands. Treatment depends on the underlying cause but may include hydration, medications, or surgery.
When to Seek Help
Occasional constipation, such as going a day or two without a bowel movement, is usually harmless and can often be managed with simple lifestyle changes like increasing dietary fibre, staying hydrated, or getting more physical activity. However, persistent or worsening symptoms may indicate an underlying health concern that needs medical attention.
You should consider seeking help from a healthcare provider or gastroenterologist if:
- Constipation lasts longer than three weeks:
When your bowel movements are consistently infrequent or difficult over an extended period, it may point to an issue beyond temporary dehydration or diet. Prolonged constipation can also lead to complications like haemorrhoids, anal fissures, or fecal impaction. - You experience severe abdominal pain, blood in your stool, or unexplained weight loss:
These symptoms are red flags. Blood in the stool can signal haemorrhoids but may also indicate more serious conditions like colorectal polyps, ulcers, or even cancer. Unexplained weight loss and persistent pain often suggest that something more systemic is occurring. - You suspect a systemic medical condition:
If constipation is accompanied by other signs like fatigue, numbness, bloating, muscle weakness, or neurological symptoms, it could be part of a broader issue such as hypothyroidism, diabetes-related nerve damage, Parkinson’s disease, or a hormonal imbalance. Identifying the root cause early can make treatment more effective and prevent complications. - Your daily life is being disrupted:
If you find yourself avoiding meals, skipping social events, or obsessing over your bowel habits, that’s a sign the problem is affecting your quality of life and deserves attention.
It’s important to consult with a healthcare professional. Gastroenterologists such as Dr Fernandes Mark Lee often conduct comprehensive evaluations, including blood work, imaging, and functional testing, to identify the root cause.
Proactive Steps to Take
- Track your bowel habits. Log frequency, stool type (use the Bristol Stool Chart), and any accompanying symptoms.
- Review your medications. Some, such as opioids, antacids, and certain antidepressants, can worsen constipation.
- Maintain a healthy diet. While medical factors may dominate, fibre, fluids, and movement still play a key role.
- Communicate changes. Even minor shifts in bowel function deserve mention, especially alongside abdominal pain or systemic symptoms.
The Bottom Line
Chronic constipation is more than an inconvenience, it can be a clue to deeper health issues affecting the endocrine, neurological, or gastrointestinal systems. Conditions like hypothyroidism, diabetes-related neuropathy, Parkinson’s disease, irritable bowel syndrome, and hypercalcaemia are all potential culprits. If constipation doesn’t resolve with lifestyle changes, it’s important to investigate thoroughly.
Gastroenterologists, including Dr Mark Lee, are trained to differentiate between routine and serious causes of constipation. By combining symptom tracking, diagnostic testing, and tailored treatment, you can address not just the symptom, but its origin.
