Constipation in older people is often blamed on too little vegetables or water, but the real cause is frequently something else — and knowing which link is stuck is what makes a fix work.

• Aging itself slows the gut, so stool sits longer, dries out, and the urge to go gets weaker.
• Seven conditions can drive it: diabetes-related nerve damage, an underactive thyroid, Parkinson's, stroke, dementia, other nerve diseases, and electrolyte problems.
• Common medicines are also culprits — opioid painkillers, iron and calcium pills, anticholinergics, and some antidepressants.
• Many older people deliberately drink less to avoid night-time trips to the bathroom, and weaker teeth or swallowing cuts out vegetables, fruit, and beans.
• Piling on more fiber can backfire if there is already hard impacted stool, heavy bloating, or a problem at the exit — that needs a proper check instead.

Outlook: Practical steps are a fixed toilet time 15–30 minutes after breakfast, daily walking or stretching, a small footstool with a slight forward lean, and a review of any new drugs or supplements — with blood in the stool, unexplained weight loss, ongoing pain, vomiting, or sudden worsening, see a doctor rather than adjusting diet alone.