Ms. Holden is a registered dietitian specializing in Parkinson's disease. She has published research, books, articles, and manuals on nutrition and PD, including "Eat well, stay well with PD." For more information you may call (USA) 877-565-2665, or 970-224-5066; or visit her website: http://www.nutritionucanlivewith.com/
Beans and Parkinson's
disease
In the past few years, I've been increasingly asked for information
about fava beans as a source of levodopa. It's clear that many people are trying
fava beans without fully understanding their properties. This article is designed
to answer questions that have arisen about fava and Parkinson's disease (PD).
I hope this may clear up some of the confusion about the bean, and encourage people
to discuss its use with their doctors and dietitians.
This bean is a legume
called "fava" (fah-vuh), faba, broad bean, and horse bean. Its botanical
name is "Vicia faba." There are many species of faba; however, the "faba
major"is the bean of concern here. It grows in a long pod, like a giant green
bean, with large, flat seeds inside. It has been eaten for thousands of years
throughout the world, especially in the Mediterranean region.
How are fava
beans related to PD?
Fava beans contain levodopa, the same chemical in Sinemet,
Madopar, Dopar, Larodopa, and other levodopa-containing medicines used to treat
PD. In fact, the entire fava plant, including leaves, stems, pods, and immature
beans, contains levodopa.
The amount of levodopa can vary greatly, depending
on the species of fava, the area where it's grown, soil conditions, rainfall,
and other factors. It appears that the young pod and the immature (green) beans
inside the pod contain the greatest amount of levodopa, and the mature, or dried
bean, the least. Three ounces (about 84 grams or ½ cup) of fresh green
fava beans, or three ounces of canned green fava beans, drained, may contain about
50-100 mg of levodopa. If using the young pod as well as the beans, the amount
of levodopa may be greater than that in the fresh beans alone.
What effect
do fava beans have on PD?
Some small studies have shown that the levodopa
in fava beans can help control the symptoms of PD, just as medications containing
levodopa do. In fact, a few people report that the effects from fava last longer
than the effects from medications. Some researchers believe fava beans may contain
other substances besides levodopa that could be helpful.
However, although
some people report good effects, others find no antiparkinson effect from fava
beans at all; and still others report adverse effects, such as nausea and dyskinesia.
Much more research needs to be done to determine how effective fava beans may
be.
Are there any problems associated with eating fava beans?
Yes, there
a number of concerns to be aware of:
Variable levodopa amounts. Because fava
plants have varying amounts of levodopa, it's possible to get either too much
or too little levodopa. Too little levodopa will not relieve PD symptoms; and
too much levodopa can cause overmedication effects, such as dyskinesia - particularly
if other PD medications are being used at the same time. Also, the levodopa can
cause nausea in some people.
Allergies. Raw fava beans can produce an allergic
reaction in some people, including discomfort, and occasionally, coma. Cooking
may prevent allergic reactions.
Monoamine oxidase inhibitor (MAOI) use. Another
consideration is the use of fava for people who take MAOIs. These include: isocarboxazid
(Marplan); phenelzine (Nardil); tranylcypromine (Parnate); and selegiline (deprenyl,
Carbex, Eldepryl).
MAOIs taken in combination with pressor agents (foods
high in dopamine, tyramine and phenylethylamine), can bring about a dangerous,
and sometimes fatal, increase in blood pressure. Levodopa in medications or in
fava can convert to dopamine in the bloodstream. It should be noted that selegiline
is a different type of MAOI (MAOI-type B), and in the amount normally used by
people with PD (10 mg daily), it is not thought to pose a risk when used with
dopamine. However, people using any MAOI should discuss foods containing pressor
agents with their physicians and dietitians.
Favism (G6PD deficiency). Favism
is an inherited disease in which a person lacks an enzyme called glucose-6-phosphate
dehydrogenase (G6PD). When these people eat fava beans, they develop a condition
called hemolytic anemia. This anemia causes red blood cells to break apart and
block blood vessels. When such blockage occurs in the kidneys, it can result in
kidney failure and even death. Although favism is usually detected in childhood,
adults can be affected as well.
G6PD deficiency is rare, occurring mostly
among people of Mediterranean, African, and Southeast Asian descent, but others
can be affected as well. Your physician can perform a blood test for G6PD to determine
whether you are at risk. If you find you have inherited G6PD deficiency, your
dietitian can help you locate other foods that may be of concern, and can help
you plan safe and healthful menus. For more information on favism, see Resources
at the end of this article.
Should you eat fava beans if you have Parkinson's
disease?
Many people with PD can benefit from use of fava beans. If you'd
like to try them, discuss it with your physician first. Besides MAOI use and risk
for favism, your doctor may want to adjust the amount and/or timing of your PD
medications.
If your doctor agrees that you should try using fava beans, he
or she will probably ask you to start out with a very small amount at first, to
see what effect, if any, fava has for you. An ounce (about 28 grams, or two tablespoons
of beans) a day is probably right for most people to begin with. After a week
you should notice whether there is any effect, and if not, your doctor may suggest
that you increase the amount. If the fava beans reduce PD symptoms, your doctor
may want to adjust your other PD medications.
How often should I eat fava
beans?
There is too little information available to give an exact answer;
also, each person with PD is different, and has different medication needs. Some
people report a half cup (4 ounces, 112 grams) of fava a day, or even every other
day, gives good results. Begin with a small amount, increasing gradually under
your doctor's supervision, until you find the combination of fava and/or PD medications
that's right for you.
Even if fava beans help, you shouldn't eat too much.
If you fill up on fava, you'll be too full for other foods, and will miss out
on the benefits they offer. A dietitian can help you plan menus that include fava
beans and will best meet your personal needs.
Where can I get fava beans?
Fresh pods and/or green fava beans are available in season at specialty produce
markets and some specialty foods shops. They may also be found at Middle Eastern
markets, some supermarkets, and farmers' markets. Grocery stores may be willing
to special order the fresh pods or beans in season, frozen pods/beans, or canned
green fava beans, such as produced by Krinos or Cortas. Be sure to specify "green
fava beans," not dried or mature beans. For more information, see Resources.
Nutrient information for fava beans
Besides levodopa, fava beans are rich
in valuable nutrients. Fava pods with beans are a good source of iron, magnesium,
potassium, zinc, copper, selenium, and many vitamins. The beans alone are also
good - 3 ½ ounces (98 grams) of cooked fresh beans contain 56 calories,
20 grams carbohydrates, 5 grams protein, 2 grams fiber, and substantial amounts
of iron, magnesium, and vitamin C.
How do I prepare fava beans?
The pods,
including beans, are best eaten when very young, before a "string" forms
along the side. They can be steamed or boiled until tender. Add some olive oil
or butter, lemon juice, salt and pepper, and serve as a vegetable side dish, like
snow peas.
To use the fresh green fava beans, shell the beans from the pods,
like green peas. Then boil or steam them till tender - usually two to 10 minutes,
depending on size and age. Add butter, salt and pepper, or your own favorite seasoning,
and serve as a side dish. You can also add the cooked beans to salads. If the
beans seem too chewy, cook for 8-10 minutes, then cool and slip off the outer
skins; cook a few more minutes if needed. Some people like to eat the skins, others
find them too tough.
In conclusion, fava beans are an excellent food, as well
as a possible way to help fight the effects of PD. Discuss use of fava with your
doctor and registered dietitian. Here's to your good health!
RESOURCES
Sources for fava beans: (Be sure to ask for green, or immature, fava beans, either
the beans themselves or the entire pod. The pods may be fresh or frozen; the beans
may be fresh, frozen, or canned.)
International Gourmet
32945 Casena Street,
Temecula, California 92592
1 - 909 - 303 - 3836
Will ship fresh (in
season), frozen green (immature), or canned green (immature) fava beans