The effects of Alzheimer’s on the body

The effects of Alzheimer’s on the body include changes to movement, balance, digestion, continence, and swallowing, not just memory. These physical changes can appear at any stage of the condition, sometimes before memory loss becomes obvious, and tend to become more pronounced as the disease advances. Two people with the same diagnosis can experience very different symptoms, and some changes, such as a UTI-related spike in confusion, can look like a sudden decline in the condition rather than a treatable infection. Recognising these changes early makes it easier to respond and to put the right support in place at each stage.

Key Insights:

• Alzheimer’s damages the brain cells that control movement and balance, so physical changes such as slower walking or shuffling can appear before severe memory loss.
• Falls are a major risk as the disease progresses, with spatial awareness and balance deteriorating even in early stages.
• Weight loss and reduced appetite are common in moderate to advanced Alzheimer’s, as people forget to eat, lose interest in food, or develop swallowing difficulties.
• Urinary tract infections occur more frequently in people living with dementia and can cause a sudden rise in confusion, agitation, or behaviour changes.

How does Alzheimer’s affect the body?

Alzheimer’s gradually damages brain cells that send signals to muscles and organs. This affects coordination, balance, appetite, digestion, and the ability to swallow or speak clearly.

Physical changes can appear early in the disease progression. Recognising these changes helps you prepare and maintain your loved one’s comfort and dignity.

“Alzheimer’s gradually affects coordination and spatial awareness, increasing fall risk as the condition advances. Our carers are trained to spot these subtle changes early, adjusting support to maintain mobility and independence safely at home.”

– Adebola Adeyemi, Clinical Manager (Nurse) at Hometouch

Why does Alzheimer’s affect walking and movement?

Changes in walking or posture can be early physical signs of Alzheimer’s. Walking safely relies on thinking skills such as planning, judging distances, and coordinating balance, all of which the Alzheimer’s Society notes can be affected by dementia. Because different types of dementia affect movement in different ways, some people notice shorter steps, drift to one side, or walk more slowly. Over time, they may shuffle, drag their feet, or need help standing and walking safely.

Tip: Regular gentle activity, like walking or physiotherapy, helps maintain strength and reduce stiffness. In our experience at Hometouch, subtle changes in gait are often the first physical sign families notice, and one of the earliest prompts to consider whether additional support at home would help.

Balance and coordination problems

Alzheimer’s can affect spatial awareness and coordination, making it harder to judge distances or stay steady. The person may bump into furniture or struggle with stairs and uneven surfaces.

Balance changes increase the risk of trips and falls, and well-lit rooms, clear walkways, and supportive footwear or walking aids can all improve safety at home.

Muscle stiffness and shaking

Muscle stiffness can occur in Alzheimer’s, although it’s more commonly associated Lewy body dementia and Parkinson’s disease. The Alzheimer’s Society notes that different types of dementia cause different movement problems, and where symptoms overlap with how Parkinson’s affects the body, such as stiffness, slower movement, or tremors, it’s worth discussing with a GP to check what’s driving the change.

In later stages, muscles may tighten and waste away, making sitting or lying uncomfortable for extended periods. Carers need to reposition regularly to prevent pressure sores and maintain comfort. A specialist dementia carer will typically manage this as part of a structured daily routine.

Why do people with Alzheimer’s lose weight?

As cognitive and coordination abilities decline, eating becomes more difficult. A person with Alzheimer’s might forget to eat, lose interest in food, or struggle with chewing and swallowing.

Dementia UK notes that weight loss and eating difficulties are common as dementia progresses, and that not eating and drinking enough can also increase the risk of dehydration, urinary tract infections, and confusion. Soft meals, smaller portions, and mealtime supervision help maintain nutrition and prevent dehydration.

If swallowing difficulties develop, a speech and language therapist can provide tailored guidance. In later stages, these difficulties can contribute to aspiration pneumonia, covered in more detail in the swallowing section below.

In our experience at Hometouch, introducing a consistent mealtime routine at the same time, same place, low distraction, can significantly improve food intake in the earlier and middle stages of Alzheimer’s, even when appetite has noticeably declined.

Why are UTIs common in people with Alzheimer’s?

Reduced mobility, low fluid intake, or poor diet can lead to constipation. Over time, bowel control may be lost. NICE guidance on dementia identifies continence management as a core component of dementia care planning, recommending early assessment and a structured toileting routine.

Urinary tract infections (UTIs) occur more frequently in people living with dementia. They can cause a sudden increase in confusion, abdominal pain, or incontinence – sometimes mistaken for a rapid decline in the condition itself. The NHS recommends prompt treatment to prevent complications and avoid unnecessary deterioration. In advanced Alzheimer’s, the brain may lose control of bladder and bowel function entirely.

Families navigating continence changes can find practical support through Hometouch’s dementia care at home service, where carers are trained to manage these needs with sensitivity and without disruption to daily routine.

Swallowing and breathing difficulties

In late-stage Alzheimer’s, the brain can lose control of the muscles needed for swallowing and breathing. A person may cough or choke when eating, as food or drink enters the airway rather than the throat. The Alzheimer’s Society identifies swallowing difficulties as one of the defining features of late-stage dementia, affecting nutrition, hydration, and respiratory health.

This can lead to aspiration pneumonia – an infection that develops when food or liquid enters the lungs. Thickened fluids, pureed foods, and guidance from speech therapists or dietitians reduce these risks. Families considering around-the-clock support at this stage may want to explore 24-hour care at home as an alternative to hospital or residential placement.

When should you consider extra support at home?

Not every physical change means it’s time for extra help, but some combinations are a useful trigger to review the current care plan. Falls, ongoing eating difficulties, continence changes, and a family carer struggling to keep up with day and night support are all signs it may be worth having that conversation sooner rather than later.

Speak to our clinically led team about the changes you’re noticing and the options available, including live-in care and shorter-term support.

Many families start with visiting or overnight support and move to live-in care as needs increase. If cost is part of the decision, our guide to the cost of live-in care sets out what’s typically included.

Frequently asked questions

What are the first physical signs of Alzheimer’s disease?

The earliest physical signs are often changes in walking and posture – shorter steps, slower pace, or drifting to one side. These can appear before significant memory loss and are caused by disruption to the brain signals that control muscle movement. Balance and coordination difficulties frequently follow, increasing the risk of falls.

Can Alzheimer’s cause problems with eating and swallowing?

Yes. As Alzheimer’s progresses, a person may forget to eat, lose interest in food, or develop difficulties chewing and swallowing. In later stages, swallowing difficulties can lead to aspiration pneumonia, where food or liquid enters the lungs. A speech and language therapist can advise on safe eating strategies, including thickened fluids and modified food textures.

Why do people with Alzheimer’s get urinary tract infections?

People living with Alzheimer’s are more susceptible to UTIs due to reduced mobility, lower fluid intake, and difficulties recognising or communicating the need to use the toilet. A UTI can cause a sudden, significant increase in confusion that may be mistaken for a rapid decline in the condition. If you notice a sudden change in behaviour or thinking, it’s worth contacting a GP promptly, as UTIs are usually straightforward to treat once identified.

How does Alzheimer’s affect mobility in later stages?

In later stages, muscle stiffness and wasting become more pronounced, making independent movement increasingly difficult. A person may need support to stand, walk, and reposition. Regular repositioning by a carer is essential to prevent pressure sores. 24-hour care at home or live-in support is often the most appropriate option at this stage.

What are the seven stages of Alzheimer’s, and how do physical symptoms change?

Alzheimer’s is often described in seven stages, ranging from no noticeable symptoms to very severe cognitive and physical decline. Physical symptoms such as unsteady walking, incontinence, and swallowing difficulties tend to cluster in the later stages, though the exact timing varies between individuals. Our guide to the seven stages of Alzheimer’s disease sets out what to expect at each point.

When should I consider live-in care for someone with Alzheimer’s?

Live-in care is worth considering when physical changes – falls, eating difficulties, or continence issues – are affecting safety and daily life, and when family carers are finding it difficult to provide consistent support. A free care assessment with the Hometouch team can help clarify what level of support is appropriate. Arrange a free assessment to talk through the options.

How can home care support the physical effects of Alzheimer’s?

Home care built around a person’s changing physical needs, not just their diagnosis, can make each stage of Alzheimer’s safer and more comfortable. This includes support with mobility and fall prevention, nutrition and hydration, continence care, and safe eating as swallowing becomes more difficult. Hometouch’s specialist dementia carers are trained to recognise these changes early and adjust support accordingly, as part of a personalised care plan reviewed regularly.

Alzheimer’s progressively affects both mind and body, and the physical changes covered in this article, from early shifts in gait to late-stage swallowing difficulties, are rarely straightforward to manage alone. Early awareness and a flexible care plan make a meaningful difference to comfort, safety, and quality of life at home.

Every family’s experience of these changes is different, and there’s no single right time to ask for extra support. If you’re starting to notice some of the signs covered here, whether that’s a change in walking, weight loss, or a sudden spike in confusion that might be a UTI rather than the condition itself, it’s worth talking it through with someone who understands the clinical picture as well as the practical one.

Speak to our care team about your situation – no pressure, just answers.