Diet, Nutrition and Parkinson's
A Special Diet for Parkinson's Disease
"A special diet for Parkinson's disease has evolved out of the knowledge that diet can interfere with the effectiveness of levodopa. Therefore, this pertains only to those people receiving levodopa who are experiencing fluctuations in their mobility."
Why are there interactions between levodopa and diet?
First we must understand some special features of levodopa.
1. Levodopa has a very short plasma half-life. This means that levodopa rapidly disappears from blood.
This takes from 60 to 90 minutes, therefore, the blood levels of the drug bounce up and
down. It is easy to imagine that anything that would delay it from entering the blood would also
delay how much gets to the brain and, consequently, would affect how well the medication works.
2. Levodopa is not absorbed from the stomach, but from the small bowel. Therefore, anything that
delays the emptying of the stomach contents into the small bowel can decrease absorption of
the drug.
3. Levodopa is a type of amino acid called a large neutral amino acid (LNNA). To be absorbed, it
must attach itself to carrier molecules in the wall of the intestine, which then carry it across the
intestinal wall to the blood. This same mechanism is present to move levodopa from blood to brain
Therefore, anything that also uses this carrier system can compete with levodopa and potentially
interfere with its ability to get to the brain.
What factors interfere with the absorption of levodopa?
Since levodopa is not absorbed into the blood stream,the stomach's role is simply to deliver the
medication to the place where it is absorbed, which is the small bowel. Because of this, the contents
of the stomach, the rate at which they are digested, and the rate at which the stomach empties into the
small bowel became very important. Another consideration is that there are enzymes in the stomach
lining that play a role in metabolizing the drug. Therefore, the longer the drug stays in the stomach, the
more it will be chemically broken down and less drug will be available for absorption. There are many
dietary factors that affect how rapidly the stomach empties its contents in regard to the food groups, fat
takes the longest to be digested, followed by protein, and then carbohydrates. Dietary fiber also slows
the emptying of the stomach. Other factors, such as increased stomach acidity and certain medications
(eg, anticholinergics) have been shown to slow the rate of stomach emptying. Experiments are being
done to see if decreasing stomach acidity with antacids might improve the absorption or the drug in a
few patients. It should also be noted that stomach or bowel diseases, as well as constipation, can affect
the rate of absorption.
Research has compared the absorption of levodopa when it is given on an empty stomach versus when
it is given with a meal. This clearly demonstrates that in some people, taking the drug with a meal can
dramatically delay the absorption or the drug.
What is the recommendation for timing of medication?
Sinemet should be taken 15 to 30 minutes before meals to ensure the most predictable absorption.
(The same recommendation would apply for Sinemet CR, although it is not thought to be as critical for its absorption.)
There are two exceptions to this rule:
1. If this drug produces nausea, the medication should be taken with a light, low-protein snack such
as crackers and juice or, if necessary, with a meal.
2. The second exception is if a person experiences too much diskinesia or involuntary movement
after taking the drug. Diskinesia may be improved by slowing the absorption of the drug by taking
it with meals.
What dietary factors affect levodopa getting from blood to brain?
Once levodopa gets from the stomach to the small bowel, it is absorbed into the blood stream. As
mentioned earlier, to get across the intestinal wall, levodopa must be transported by attaching to carrier
molecules. This carrier system transports the drug from intestine to the blood stream and from the
blood stream to the brain. It can be likened to seats on a train. There are a limited number of seats and
when these seats are filled, no more levodopa can be transported. At the level of the intestine, this is
not a problem, since the "train" has a large carrying capacity; but at the level of the brain, the "train"
is much smaller. Other LNAAs found in the diet use the same carrier system as levodopa. These amino
acids are isoleucine, leucine, valine, phenylalanine, tryptophan, and tyrosine. Meals high in protein.
and therefore high in LNAAs can interfere with the ability of levodopa getting into the brain by taking
up the seats on the train.
Who should try the low-protein diet?
Consideration should be given to the severity of the disease. If a person has motor fluctuations that
interfere with activities or has noticed that food seems to interfere with how well their medication works,
a reduced-protein diet may help these problems.
How much protein should be eaten?
People who need to lower the protein in their diet should reduce it to the recommended daily allowance
of protein. Most Americans eat far more than this on a daily basis The RDA for protein is 0.8 g/kg
(0.36 g/lb) body weight.
How should the protein be distributed throughout the day?
Restricting protein to the RDA, compared with the typical American consumption of protein, clearly
improves the time a person is mobile throughout the day. Restricting the majority of the protein to the
evening meal, compared with evenly distributing it throughout the day, further improves the amount or
time a person is mobile The decision between these two methods of distribution depends on the
severity of the disease and the person's life-style needs.
For the person who has moderate motor fluctuations, a diet with protein spread evenly throughout the
day will reduce the likelihood of high levels of amino acids and improve the amount of mobile time.
For the person with marked motor fluctuations, a diet with protein restricted to the evening meal will
allow for an even more predictable response. The drawback to this diet is a less mobile evening. If this
is compatible with the life-style of the patient, this diet is best for the person who has marked
fluctuations in mobility.
Do carbohydrates play a role in the parkinsonian diet?
It has been shown that increased carbohydrates result in increased insulin secretion, which lowers
LNAAs circulating in the blood. Therefore, increased carbohydrates plus a decreased protein intake may
further enhance the delivery of levodopa to the brain by lowering the competition with other LNAAs. The
therapeutic role of carbohydrates in the parkinsonian diet needs further investigation.
What are the recommendations for carbohydrate use in the parkinsonian diet?
If weight is lost when protein is lowered in the diet, carbohydrates should be increased to maintain
ideal body weight. The amount should be determined with the help of a dietician. If excessive but
predictable dyskinesia results from the increased carbohydrates and lowered dietary protein, it may be
helpful to try to evenly distribute carbohydrate intake throughout the day, as well as reduce the dosage
of the medication.
High Fiber Diet for Parkinson's:
The following tips will help decrease a common side effect of Parkinson's: constipation.
The watch words are: " FIBER, FLUIDS, and EXERCISE."
- Aim for 25 to 35 grams of fiber per day
- Eat a well balanced diet, including high fiber foods whole grain flours, breads, rice and cereals
raw and cooked vegetables dried and fresh fruits nuts and seeds, including pumpkin, sunflower, and
sesame.
- Add unprocessed bran to food - start with one teaspoon of bran per day, increase by one
teaspoon per day, until you have reached 1 tablespoon twice a day (6 teaspoons).
- Drink plenty of decaffeinated, non-alcoholic fluids (6 to 8 glasses per day)
- Limit intake of fatty foods (French fries, onion rings, fast food, cheese, fatty meat) since high
fat foods decrease the activity of the intestinal tract.
- Thoroughly chew your food.
- Eat at regular hours and include at least one high fiber food at each meal
- If choosing a fiber supplement, choose natural products such as metamucil or citrucel: avoid chemical laxatives.
- Increase physical activity.
Anti-Constipation Fruit Paste
1 pound pitted prunes
1 pound raisins
1 cup lemon juice
1 pound figs
1 cup brown sugar
3-1/2 or 4 ounce package Senna Tea (can be found in health food stores)
Steep tea 5 minutes in 3-1/2 cups boiling water. Strain tea to remove tea leaves.
To 2 cups tea, in a large pot, add fruit and boil for 5 minutes.
Add sugar and lemon juice.
Cool.
Use food processor or blender to turn mixture into a smooth paste.
Place in plastic container and put in freezer. (the paste will not freeze and will keep a long time)
Take 1 or 2 tablespoons daily.
"Special Recipe"
one cup applesauce
one cup oat bran
1/4 cup prune juice
and spices like nutmeg, cinnamon, etc. to taste
may be stored in fridge or pre-measure servings in ice cube tray and thaw
as needed
Begin by having 2 tablespoons each evening followed by 8 oz. glass of
water----after 1 week increase this to 3 tbspoons, after third week,
increase to 4 tbspoons.....also, remember to discuss this with your
doctor when deciding to go on this regimen.
