Nutrition and Parkinson's Disease: What Matters Most?

By Karol Traviss, MSc, RD

Navigating the maze of nutrition information and advice available to the public is challenging, even for a healthy consumer. Add Parkinson's disease to the mix and the challenges spiral higher. The nutritional issues faced by people with PD are complex and diverse, and many of the issues do not have clear answers.

When it comes to nutrition, what matters most? Here we help you to answer that question.

Eat a balanced diet

It is difficult for a person to feel well and maintain energy when he or she is not eating properly. Eating properly involves eating regularly (no meal skipping), eating a variety of foods from all of the food groups (grains, vegetables, fruit, milk/ dairy, meat/beans) and eating prudently to maintain a healthy weight. Although this sounds like simple advice, implementing it can be a challenge, particularly if you have a hectic lifestyle or if the symptoms of Parkinson's are affecting your ability to shop, prepare food and eat.

If you are not eating as well as you should, you may wish to consult a registered dietitian who can help assess your food intake and discuss with you strategies for improving your diet. It is also helpful to seek the assistance of others for shopping and meal preparation, and to keep easy-to-eat, nutritious foods on hand. If you have any problems with depression, this can interfere with appetite; be sure to discuss the problem with your doctor.

Maintain bone health

People with Parkinson's are prone to osteoporosis, a disease caused by low bone-mineral density. Risk factors for osteoporosis include older age, low body weight, smoking, excessive alcohol intake, limited exposure to sunlight, inadequate intake of vitamin D and calcium and lack of weight-bearing exercise.

Osteoporosis can be especially worrisome to a person with Parkinson's who faces an increased risk of falling. The inevitable result is an increased risk of fractures, which are dangerous and painful and tend to be detrimental to one's quality of life. Ask your doctor about having your bone-mineral density checked. If it turns out to be low, medical treatments may be available.

To maintain bone health, make sure your diet includes plenty of calcium and vitamin D.
People who are over the age of 50 should consume 1500 mg of calcium and 800 IU of vitamin D daily. Milk and milk products are the richest dietary source of calcium. Three servings per day are recommended (one serving is one cup of milk or yogurt, or one and one-half ounces of hard cheese). Although there are other calcium-containing foods (e.g., tofu, calcium-fortified soy-based beverages, orange juice and dark leafy greens), calcium from non-dairy sources may not be well-absorbed.

You can also obtain vitamin D by getting outdoors regularly and consuming foods rich in vitamin D (e.g., vitamin D-fortified milk, yogurt or breakfast cereals and fatty fish). If you live in a region with limited sunshine and/or do not consume many vitamin D-rich foods, use of a nutritional supplement is recommended.

Supplements come in several forms. Some are easier to tolerate than others. Your pharmacist will be able to advise you on the different kinds available.

Maintain bowel regularity

Constipation is common in Parkinson's disease. While this can be an embarrassing issue to raise with your healthcare provider, prevention and treatment of constipation is critical, as severe constipation can lead to bowel obstruction, a potentially life-threatening condition.

Although the constipation observed in Parkinson's is due in large part to the disease itself, lifestyle measures can be useful for managing it. These include eating foods high in fiber (whole grain bread, bran cereals or muffins, fruits and vegetables, beans and legumes and prunes) and drinking plenty of fluid. Then there is exercise, which helps maintain bone density as well as eases constipation.

If you are not able to achieve bowel regularity through lifestyle alone, laxatives and other bowel interventions may be required. Make sure to see your doctor if constipation persists.

Balance medications and food

The medications used for Parkinson's can themselves cause nutrition-related side-effects, such as nausea and poor appetite. Typically these side-effects are most severe when a medication is first prescribed but some individuals have continuing problems with them. Taking a small snack (such as ginger ale and a few crackers) along with medications may help to control these side-effects. If nausea or poor appetite persist, contact your doctor, as these symptoms can lead to undesired weight loss.

Amino acids (from dietary protein) can interfere with the uptake of levodopa into the brain. If you find (not everyone experiences this) that eating high-protein food (such as meat, fish, poultry and dairy products) decreases the effectiveness of levodopa, keep the meat portion of your meal to about the size of a deck of cards and take your Sinemet® half an hour prior to a protein-containing meal.

Do not use a restricted-protein diet; the problem, if you find you have one, is usually with the timing of the protein intake, not its total quantity over the course of the day.

Do "wonder" foods or supplements delay progression of Parkinson's?

Supplements (both nutritional and herbal) and dietary therapies are high on the list of complementary therapies used by people with Parkinson's. In spite of compelling theories about the effectiveness of various supplements or dietary factors in delaying progression of the disease, we lack definitive, evidence-based answers. Some therapies have been studied only in test tubes or with laboratory animals. Few human trials have been done (e.g., those examining antioxidant vitamin supplements), and most have produced disappointing results. Coenzyme Q10 is one nutritional supplement that is of considerable interest to the scientific community and is under study to determine if it has any potential benefit in Parkinson's disease.

Some foods that are in the "won't hurt and might help" (at least in theory) category include coffee (several population studies have suggested that coffee may be protective against Parkinson's, particularly in men); green tea; a variety of fruits and vegetables; foods rich in vitamin E such as wheat germ; nuts and seeds; and vegetable oil. If the antioxidants present do not help with Parkinson's symptoms, they may help with some other aspect of health so there is certainly no reason not to use them.

When thinking about the potential value of using this or that supplement, consider the factors of cost, safety and effectiveness and be sure not to be "taken in" by hyped headlines. For example, a recent headline read, Vitamin B6 May Cut Risk of Parkinson's Disease. Behind the headline: this study finding, while interesting, was only observed among smokers and the study addressed only the onset, and not the progression, of Parkinson's.

However tempting it may be to seek out "wonder" foods and supplements, at this time there is not enough evidence to suggest that they play a major role.

Adjust nutritional priorities for your situation and stage of disease

Parkinson's symptoms vary from person to person and by stage of disease. Each person must set nutritional priorities based on the issues they face. In early Parkinson's, we should all emphasize eating well and maintaining a healthy weight. As the disease progresses, we should adjust our diets to manage specific new symptoms as they emerge (such as swallowing difficulties, medication side-effects, bowel issues and eating challenges). The goal of thoughtful nutrition is not just to ease PD symptoms; it is also to allow you to continue to use food as a source of pleasure in your life.

Karol Traviss, MSc, RD is a registered dietitian on faculty at the University of British Columbia in Vancouver, Canada. She has worked collaboratively with the British Columbia Parkinson's community for many years and spoke on complementary nutritional therapies at the 2006 World Parkinson Congress.