Obsessive-Compulsive Disorder (OCD)
While a balanced, nutrient-rich diet and adequate sleep are standard recommendations for general good health, sleep and diet are especially important for people with OCD. Certain herbs and nutritional supplements act directly on the nervous system, promoting relaxation and feelings of tranquility. Others may relax tense muscles, ease stress-related headaches, soothe gastrointestinal upset, and encourage restful sleep.
Tryptophan. The amino acid tryptophan is a precursor to serotonin. It has been shown that serotonin-promoting tricyclic antidepressants and SSRIs are successful in treating OCD and that tryptophan is effective in the treatment of other anxiety disorders. Thus, researchers have hypothesized that tryptophan supplementation might reduce OCD symptoms while tryptophan depletion might exacerbate them.
In one study, depletion of tryptophan in patients with OCD resulted in more significant sleep disturbances (altered rapid eye movement parameters, decreased total sleep time) than experienced by healthy controls (Huwig-Poppe 1999). However, several other studies have shown that depletion of tryptophan has no effect on OCD or Tourette’s syndrome symptoms, although some mood-lowering changes were reported (Smeraldi 1996; Barr 1994). The fact that researchers observed a different response in OCD than depression and panic disorder trials suggests that OCD treatment may depend less on the availability of serotonin and more on changes that occur further along in the synthesis of serotonin. Another possible explanation is that the tryptophan-depletion study in OCD did not introduce a challenge, as was done in the panic disorder studies and which may have triggered a relapse in symptoms (Bell 2001).
In a double-blind, placebo-controlled study, researchers found that acute tryptophan depletion caused patients to experience significantly greater subjective distress when provoked with triggering situations (Berney 2006).
Inositol. Inositol, a nutrient related to the vitamin B complex, is necessary for the proper formation of cell membranes. Among inositol’s many functions is its ability to affect nerve transmission, aid in the transportation of fats within the body, facilitate the action of various methylating agents, and play an important role in reproduction, embryogenesis, and prevention of neural tube defects (eg, spina bifida).
In a crossover trial comparing inositol supplementation to placebo, 13 patients with OCD took inositol and placebo for 12 weeks (6 weeks each). Patients experienced a significant reduction in OCD symptoms taking inositol compared with the weeks taking placebo (Levine 1997).
St. John’s wort. St. John’s wort is an herb with a history of successful treatment for depression and other psychological disorders. Its value in the treatment of OCD may lie in its ability to selectively inhibit reuptake of serotonin, thus, act as an SSRI (Taylor 2000). Researchers have also hypothesized that St. John’s wort reduces production of cytokines induced by substance P, a neuropeptide known to cause depression and anxiety (Fiebich 2001).
N-acetylcysteine. N-acetylcysteine (NAC) is a nutritional supplement used in the treatment of many compulsive disorders (including OCD). Researchers have found that NAC works for such hard-to-treat problems as pathological gambling and compulsive hair-pulling (trichotillomania) (Grant 2009).
L-theanine. L-theanine (delta-glutamylethylamide) (in green tea), despite containing caffeine, is known to have a calming effect. A study demonstrated that L-theanine may be capable of antagonizing the stimulant effects of caffeine on brain activity in a laboratory rat model (Kakuda 2000).
One advantage of theanine is that it readily crosses the blood-brain barrier. Research shows that this ability allows theanine to directly stimulate production of alpha brain waves, which promotes deep relaxation. In one study, for example, researchers found that 50 to 200 mg theanine given to volunteers resulted in the production of alpha waves within 40 minutes of ingesting the amino acid (Juneja 1999).