Causes of Weight Loss in Parkinson’s Disease

Weight loss is common in Parkinson’s disease but the exact cause may not always be obvious as it can occur both in the early or late stage of the disease. The basic problem leading to weight loss is that the calorie intake through food is less than the calories used up through hyperkinetic movements, such as tremors. The need for a sufficient calorie intake through a healthy and balanced diet  for a person with Parkinson’s disease is essential to prevent significant weight loss.

Other Reasons for Weight Loss in Parkinson’s Disease

There may be other contributing factors for the weight loss noticed in Parkinson’s patients and these include :

  • Dysphagia or difficulty in swallowing discourages adequate intake of solid food, especially in the late stage of the disease.
  • Loss of appetite, very often due to depression or anxiety, may be a factor.
  • Difficulty in eating due to symptoms of Parkinson’s disease such as tremor, rigidity or bradykinesia (slowness in initiation of movement).
  • Dementia or other mental disturbances in a patient with Parkinson’s disease may prevent proper feeding.
  • Some patients restrict their food intake, especially proteins, as it “turns off’ the effect of levodopa.
  • Medicines used for treating symptoms of Parkinson’s disease may have certain side effects such as nausea, vomiting, constipation, heartburn, dry mouth or loss of appetite which discourages proper food intake.
  • Gastroesophageal reflux disease (GERD)– the patient avoids eating for fear of discomfort produced after meals.

Effects of Weight Loss in Parkinson’s Disease

Less intake of nutrients results in :

  • Tiredness and weakness
  • Hypotension (low blood pressure)
  • Osteoporosis (less mineral density in bones). Thinning of the bones, associated with frequent chances of falling in a person with Parkinson’s disease, result in high incidence of fractures.
  • Features of malnutrition
  • Increased susceptibility to infections such as pneumonia

Management of Weight Loss in Parkinson’s Disease

  • Eating a healthy balanced diet is the most important factor in preventing weight loss in a person with Parkinson’s disease. Enough dietary fiber, vitamins and fluids should also be included in the diet.
  • High calorie foods such as biscuits, peanut butter or desserts may help to increase weight.
  • Instead of three large meals, a person with Parkinson’s disease might find smaller, frequent meals easier to handle.
  • Protein in the diet interferes with absorption of levodopa, hence meal timings have to be planned so that absorption of levodopa is not hampered, but without restricting intake of protein. Levodopa may be taken half an hour before or one hour after taking a protein- rich diet such as meat.
  • Enough liquid intake is necessary to prevent dehydration, since chronic dehydration can lead to urinary tract infections or kidney stones.
  • Fiber in the diet and adequate vitamins and calcium are necessary.
  • While eating, it is better to cut up food into small pieces to avoid choking and to assist with digestion.
  • In case of drug therapy causing stomach upset, it is advisable to eat smaller amounts of food other than protein before taking medicines.

Proper eating and adequate nutrition are important considerations for caregivers and it is advisable to consult with a dietitian if significant weight loss is noted in Parkinson’s patient.


  1. Weight Loss in Parkinson’s Disease. Pubmed
  2. Parkinson’s and Diet.

1 Comment

  1. What do you do if all they want to eat is sugar. My brother-in-law is done to 140 lbs and looks like a concentration camp victim. He eats 5 bowls of cereal at day among other things. My sister does not know what to give him to put some weight on him and I think his doctor’s have given up on him. He was a test patient and drugs thru tube in stomach have not helped him. Any suggestions to help?

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