This syndrome is marked by an unpleasant crawling or
aching sensation in the lower legs, between the knee and the ankle,
often accompanied by restlessness in other parts of the body, especially
in the flexor muscles of the arms and legs. The discomfort appears only
at rest and elicits an irresistible need to move the limbs. It generally
appears in the evening and early night and may be associated with severe
insomnia.1
While, as usual, most of the research is preliminary,
the results of studies investigating the effects of nutrients on restless
legs syndrome (RLS) suggest that it has several causes, and that patient-specific
dietary changes, nutrient repletion and nutrient pharmacotherapy are
often effective treatments.
Dietary Factors
Based on afternoon glucose tolerance testing, many patients
with RLS, particularly if they also have spontaneous leg cramps, appear
to have hyperinsulinism causing functional "hypoglycemia"
during testing, in fact, occasional patients may have an attack of muscle
cramps concomitantly with their lowest level of plasma glucose. In an
open trial, a group of 350 patients with this type of glucose tolerance
curve were placed on a sugar-free, high protein diet along with frequent
nibbling and at least one night feeding. The vast majority experienced
a prompt remission or, at least, a striking reduction in symptoms.2
Caffeine has been shown to increase subjects' proneness
to develop symptoms at lower levels of blood glucose.3 It is therefore
no surprise that a xanthine-free diet (no coffee, tea, cola beverages,
cocoa) has been reported to be another effective dietary measure - sometimes
following a short period of caffeine withdrawal.1
Vitamins
RLS may also be an early neurologic manifestation of
folate deficiency, the most common of all the vitamin deficiencies.
Often the deficiency is not due to a poor diet, but to a genetic factor
causing a folate dependency. While not all RLS patients complain of
uncomfortable sensations, folate-deficient patients always suffer
from them.4 Since high doses of folic acid (5-30 mg daily) appear to
be needed to normalize folate nutriture and induce a recovery, baseline
lab testing and follow-up along with medical supervision is advisable.
Vitamin E supplementation has been reported to be effective
in several case reports. For example, in a group of 9 patients, 7 had
complete relief following supplementation, one had almost 75% relief
and one had 50% relief.5 About 300 IU daily appears to be effective,
although it may take up to three months for the full benefit to become
apparent.6
Minerals
Iron deficiency, which is known to cause akathisia (restlessness)
may theoretically cause restless legs syndrome by reducing dopaminergic
and opiate neurotransmission.7 Indeed, in one study, 25% of a group
of RLS patients had a low serum iron, while 24% of a group of patients
with iron-deficiency anemia had RLs.8 Iron-deficient patients respond
well to supplementation. Two months after 15 such patients had begun
to take ferrous sulphate 200 mg. 3 times daily, the patients whose serum
ferritins were lowest initially improved the most.9
Magnesium deficiency, which is known to increase neuromuscular
excitability, can also cause the syndrome.10 Once again, repletion should
be effective.
Other Nutrients
The primary role of the neurotransmitter serotonin in
the central nervous system is said to be the modulation and facilitation
of skeletal muscle function.11 If serotonin regulation plays a role
in RLS, supplementation with L- tryptophan, serotonin's nutritional
precursor, could therefore be of value. While tryptophan supplement
needs to be studied further, it did appear to be effective in the treatment
of two RLS patients even though they had failed to respond to numerous
medications.12
Summary
Evaluate your patient for functional "hypoglycemia,"
and deficiencies of folic acid, iron or magnesium, and treat as indicated.
If these specific abnormalities are not found, consider trials of vitamin
E and L-tryptophan.
Doctor Werbach cautions that the nutritional treatment
of illness should be supervised by physicians or practitioners whose
training prepares then to recognize serious illness and to integrate
nutritional interventions safely into the treatment plan.
Next Month: Nutritional Treatments for Autism
References
1. Lutz EG. Restless legs, anxiety and caffeinism.
J Clin Psychiatry 39:693-8, 1978.
2. Roberts HJ, Spontaneous leg cramps and "restless
legs" due to diabetogenic (functional) hyperinsulinism: A basis
for rational therapy. J Med Assoc 60(5):29-31, 1973.
3. Kerr D, Sherwin RS, Pavalkis F, et al. Effect of
caffeine on the recognition of and responses to hypoglycemia in humans.
Ann Intern Med 119:799-804, 1993.
4. Boutez MI et al. Neuropsychological correlates
of folic acid deficiency: facts and hypotheses, in MI Botez, EH Reynolds,
Eds. Folic Acid in Neurology, Psychiatry, and Internal Medicine.
New York, Raven Press, 1979
5. Ayres S, Mihan R. ÒRestless legsÓ syndrome: response
to vitamin E. J Appl Nutr 25:8-15, 1973.
6. Ayres S, Mihan R. Leg cramps and Òrestless legÓ
syndrome responsive to vitamin E. Calif Med 111:87-91, 1969.
7. Pall HS, Williams AC, Fonseca A, et al. Restless
legs syndrome. Neurology 37: 1436, 1987.
8. Ekborn KA. Restless legs syndrome. Neurology
10:868-73, 1960.
9. O'Keeffe ST, Gavin K, Lavan JN. Iron status and
restless leg syndrome in the elderly. Age Ageing 23(3):200-3,
1994.
10. Popoviciu L, Asgian B, Delast-Popoviciu D, et
al. Clinical, EEG, electromyographic and polysomnographic studies
in restless legs syndrome caused by magnesium deficiency. Rom J
Neurol Psychiatry 31(1):55-61, 1993.
11. Jacobs BL. Serotonin and behavior; emphasis on
motor control. S Clin Psychiatry 52: 12 (suppl);17-23, 1991.
12. Sandyk R. L-tryptophan in the treatment of restless
legs syndrome. Letter. Am J Psychiatry 143(4):554-5,1986.
Reprinted with pennission from the International
Journal of Alternative and Complementary Medicine. Green Library,
9 Rickett St., Fulham, London SW6 IRU, United Kingdom.
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