Dementia causes difficulties with thinking, memory, and behavior. It may also lead to unintentional weight loss. Not consuming adequate calories or liquids can also lead to other complications, like dehydration and chronic infections.

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“Dementia” is an umbrella term for diseases that cause difficulty with a person’s memory, thinking, and behavior, such as Alzheimer’s disease. While dementia is associated with advanced age, it can affect younger people as well.

Later stages of dementia may lead to unintentional weight loss. Keep reading to learn more about why people with dementia lose weight and when to seek help.

Learn more about dementia.

Dementia may lead to unintentional weight loss due to changes in habits around mealtimes. Usually, weight loss isn’t an issue until the moderate to advanced stages of the disease.

Reasons for weight loss in people with dementia may include:

Loss of appetite

People with dementia may not be hungry or may forget to eat. They may also lose the ability to communicate when hungry or thirsty.

Memory issues

People with dementia may have trouble grocery shopping, cooking meals, or recognizing foods. They may depend on others to prepare food and set a meal schedule.

Issues with chewing and swallowing

Dysphagia” is the term for trouble swallowing. Up to 57% of people with advanced dementia have issues with chewing and swallowing, according to a 2013 review. This may lead to weight loss, malnutrition, or dehydration.


A person’s environment can distract them from eating. Distractions can include:

  • dim lighting
  • colorful dinnerware or decor
  • glasses and utensils
  • too much activity around mealtimes

Other issues

Other issues that may cause weight loss can include:

  • underlying health issues
  • dentures that don’t fit
  • lack of exercise
  • embarrassment from trouble with eating
  • changes in the smell or taste of food

The most obvious sign of unintentional weight loss in people with dementia is a reduced body mass index (BMI).

Other symptoms include:

Before treatment, it’s important to determine whether the weight loss is directly related to dementia or some other health issue. Treating the underlying issues may help.

Changing certain habits can help with forgetting to eat or other distractions. For example, you can:

  • serve food one course or item at a time
  • remove distractions from the environment (table decor, noise, activity, etc.)
  • offer finger foods
  • offer familiar or favorite foods
  • serve soft foods to people with swallowing issues
  • eat with the person
  • offer plenty of fluids to prevent dehydration
  • set aside dedicated mealtimes
  • encourage daily exercise to stimulate appetite

Other treatments include speech therapy for issues with chewing and swallowing and physically feeding food to the person, but not forcefully.

Tube feeding (enteral feeding) is only used on a case-by-case basis. One analysis from 2019 found that tube feeding people with dementia does not lead to weight gain. Tube feeding carries risks of tube blockage, leakage, and infection.

For some people, modifying meal habits and offering different foods may help stabilize weight. In cases of weight loss caused by health issues or problems with dentures or swallowing, addressing the underlying issue may also help.

For others, weight loss may still progress. Cachexia is a condition that causes rapid muscle wasting and fat loss. In this condition, a person’s metabolism changes so that even if enough food is consumed, weight loss will continue.

People with advanced dementia may have cachexia, particularly at the end of life.

Weight loss of 5% of body weight over 6–12 months warrants investigation. Your doctor can make a diagnosis based on a physical exam and health history. They may also ask about any medications you take and any physical issues with swallowing.

Many things can cause unintentional weight loss, such as depression, medication side effects, cancer, and diabetes. Your doctor will likely want to do a full physical exam and related testing to rule out other medical issues.

What behavior signs should I look out for?

Signs a person is having trouble during meals may include misusing utensils and dinnerware, such as using a knife for dessert and pouring a glass of water into a cereal bowl.

Choking or gagging may be signs of swallowing issues.

Can dementia cause other eating issues?

Some people with dementia may crave sweet foods or overeat. How the disease affects a person’s appetite is individual.

Where can I find additional information and support?

The Alzheimer’s Association has message boards for virtual support. You can also contact Meals on Wheels for information about free meals for seniors. Your doctor can connect you with support in your community as well.

Mealtime can feel stressful when a person with dementia isn’t eating or is struggling with food. Unintentional weight loss can be concerning and lead to complications.

Speak with your doctor about any significant changes in eating behaviors and weight. Changing some habits and practicing some therapies may help. In some cases, weight loss may continue as the disease progresses.