Can Nutritional and Herbal Supplements Help Treat Obsessive-Compulsive Disorder?

What you need to know

• Some nutritional supplements like vitamin D, B12, and trace minerals may help reduce OCD symptoms, but more research is needed
• Herbal supplements such as N-acetyl cysteine, St. John’s wort, and valerian root show potential benefits for OCD in small studies
• Supplements should not replace standard OCD treatments like therapy and medication without consulting a doctor
• More large, high-quality studies are needed to confirm the effectiveness of supplements for OCD

Vitamin and mineral supplements

Vitamin D

Vitamin D plays important roles in brain development, function, and protection. Some studies have found that vitamin D levels are lower in children and adolescents with OCD compared to healthy controls. There may be a negative correlation between vitamin D levels and OCD symptom severity. However, the existing studies are small and have some methodological limitations. More research is needed to determine if vitamin D supplementation could help treat OCD.

B vitamins and related compounds

Vitamin B12, folate, and the amino acid homocysteine are involved in processes that affect neurotransmitter levels in the brain. Some studies have found lower B12 and higher homocysteine levels in OCD patients compared to controls. However, results are mixed regarding folate levels. One small study found folic acid supplementation with fluoxetine was not more effective than fluoxetine alone for OCD. The effects of B vitamin supplementation may depend on a person’s baseline levels and dietary intake.

Trace minerals

Imbalances in trace minerals like zinc, iron, and selenium may be associated with OCD. A few small studies have found:

• Lower selenium levels in OCD patients
• Improved OCD symptoms with selenium supplementation
• Lower zinc, iron and magnesium levels in OCD patients
• Greater improvement in OCD symptoms with zinc supplementation compared to placebo

However, these studies had very small sample sizes. More research is needed before drawing firm conclusions about trace mineral supplementation for OCD.

Amino acid supplements

N-acetyl cysteine (NAC)

NAC is an amino acid that may help reduce oxidative stress and regulate glutamate in the brain. Several studies have investigated NAC as an add-on treatment for OCD:

• Some found NAC plus standard OCD medication was more effective than medication alone
• Other studies found no significant benefit of adding NAC
• NAC may be more helpful for younger patients with a shorter duration of OCD

Overall, results are mixed but promising enough to warrant further research on NAC for OCD.

Glycine

Glycine is an amino acid that affects glutamate signaling in the brain. One small study found glycine supplementation led to near-significant improvements in OCD symptoms. However, the high doses required caused significant side effects like nausea. More research is needed on lower, better-tolerated doses.

Herbal supplements

St. John’s wort

St. John’s wort is an herbal supplement commonly used for depression. It may have effects on serotonin similar to some antidepressants used for OCD. However, studies on St. John’s wort for OCD have had mixed results:

• One small open-label study found benefits
• A larger placebo-controlled trial found no significant effect

More research is needed before recommending St. John’s wort for OCD. It can also interact with many medications, so patients should consult a doctor before using it.

Milk thistle

Milk thistle is an herb with anti-inflammatory and antioxidant properties. One small study found it had similar effects to fluoxetine in reducing OCD symptoms, with benefits starting around 5 weeks of treatment. However, this was only one small study, so more research is needed to confirm these effects.

Valerian root

Valerian root is an herb commonly used for sleep and anxiety. One small study found it was more effective than placebo for OCD symptoms. Benefits were seen starting at 4-8 weeks of treatment. Valerian also had a low rate of sexual side effects, which can be an advantage over some OCD medications. However, more studies are needed to confirm these potential benefits.

Other herbal supplements

A few other herbal supplements have been studied for OCD in animals or very small human trials:

• Curcumin (from turmeric) reduced OCD-like behaviors in rats
• Borage extract improved OCD symptoms compared to placebo in one small study
• Inositol showed benefits in some small studies when used alone, but not when added to SSRI medication

However, there is not enough evidence yet to recommend these for OCD treatment. Larger, high-quality studies are needed.

Conclusions

• Some nutritional and herbal supplements show potential for helping treat OCD symptoms, but most have limited evidence so far
• Vitamin D, B12, zinc, and NAC are among the more promising supplements based on existing studies
• Supplements may be most helpful as add-ons to standard OCD treatments rather than standalone treatments
• Patients should consult their doctor before trying any supplements, as some can have side effects or interactions
• More large, well-designed studies are needed to determine which supplements are truly effective for OCD