No special diets or natural foods have been shown to slow down the progression of Parkinson's disease, but there are some dietary recommendations.
Protein. High levels of proteins may affect how much levodopa can reach the brain and may, therefore, reduce the drug's effectiveness. Avoiding protein altogether is not the solution, since malnutrition can result. Most doctors recommend trying to maintain a carbohydrate-to-protein ratio of 7:1 throughout the day. This may be difficult to calculate, and some doctors recommend simply keeping proteins to 12% of total daily calories.
Good control of protein intake may help minimize fluctuations and wearing-off and may allow some patients to reduce their daily levodopa dosage.
Fruits and Vegetables and Increasing Fiber. Eating whole grains, fresh fruits, and vegetables is the best approach for any healthy life. A diet rich in fruits and vegetables may help protect nerve cell function. Many of these foods are also often rich in fiber, which is particularly important for helping to prevent constipation.
Dietary fiber is the part of food that is not affected by the digestive process in the body. Only a small amount of fiber is metabolized in the stomach and intestine, the rest is passed through the gastrointestinal tract and makes up a part of the stool. There are two types of dietary fiber, soluble and insoluble. Soluble fiber retains water and turns to gel during digestion. It also slows digestion and nutrient absorption from the stomach and intestine. Soluble fiber is found in foods such as oat bran, barley, nuts, seeds, beans, lentils, peas, and some fruits and vegetables. Insoluble fiber appears to speed the passage of foods through the stomach and intestines and adds bulk to the stool. It is found in foods such as wheat bran, vegetables, and whole grains. Fiber is very important to a healthy diet and can be a helpful aid in weight management. One of the best sources of fiber comes from legumes, the group of food containing dried peas and beans.
People whose diets have been low in fiber should increase it gradually. It is best to obtain dietary fiber, soluble or insoluble, in the natural form of whole grains, nuts, legumes, fruits, and vegetables. If it proves difficult to do so, psyllium, (found in products such as Metamucil), is an excellent soluble fiber supplement (Metamucil, Fiberall, Perdiem Fiber). Drinking lots of fluids is particularly important in preventing constipation.