What is L-theanine? What is L-theanine found in?

L-Theanine is a non-protein amino acid, predominantly found in green and black tea.

What are the benefits of L-theanine?

Benefits for anxiety

L-theanine is mostly used as support for stressful situations to calm the nervous system but at the same time allowing focus and cognitive function. For example, in a 2006 study looking at exam situations, the anti-stress effects of L-theanine were assessed in a laboratory setting using a mental arithmetic task as an acute stressor. The results showed that L-theanine intake resulted in a reduction in the heart rate (HR) and responses to an acute stress task relative to the placebo group[3].

Neuroprotective properties

It is most well-known for its anti-anxiety effects in the nervous system [1]. Clinical studies have also shown its positive effect in regulating central nervous system disorders due to its anti-stress and neuroprotective role in the example of dementia[2].

Benefits for Parkinson’s

L-theanine has also shown promise when researched in relation to Parkinson’s Disease. The neuroprotective effects of L-theanine can be attributed to its structural analogy with glutamate, the main excitatory neurotransmitter in brain. It seems to have potential to ameliorate the pathophysiological changes associated with Parkinson's disease as it displays antioxidant and anti-inflammatory properties, improves motor behavioral abnormalities and increases dopamine availability[4].

How is L-theanine used therapeutically?

Due to the calming effects of L-theanine, it is often recommended in a clinical situation alongside other herbs such as Lemon Balm and nutrients such as vitamin C. It may be used in short term situations of heightened stressors for quick effect such as support when giving presentations, if nervous about flying or other times where the body is pushed out of its comfort zone as well as longer term use where stressors can be more chronic.