› What is it?
Amino acids are the building blocks of proteins and play many critical roles in the body. The amino acid L-theanine was first identified by Japanese scientists in 1949 and has been studied since then for its many health-promoting benefits.
› Health benefits
Memory and learning
By lowering stress hormones in the body, L-theanine reduces their interference with memory and learning. Research shows that it can increase attention spans in people prone to anxiety and, in combination with caffeine, enhance focus and cognitive skills.
Stress and anxiety
Studies show that L-theanine can reduce feelings of stress and anxiety without making the subjects drowsy. It also has positive effects on the physical symptoms of stress, such as blood pressure and heart rate.
Immune function
There is some research to suggest that L-theanine improves immunity to upper respiratory tract infections. Additionally, it can improve the movement of cilia in the nose, the strands that help the body expel stale mucus from the sinuses.
Cancer
A 2011 study suggests that L-theanine helps to improve the effectiveness of some chemotherapy drugs, and other studies suggest that tea drinkers have lower cancer rates and higher survival rates when they do suffer from cancer.
Sleep
Studies on both humans and animals have shown that L-theanine can greatly improve sleep quality, including for people with schizophrenia.
› How much do I need?
No research has been conducted to determine a safe L-theanine dosage, but studies on stress and sleep have generally used 100 to 400 mg. There have been no reports of overdose or side effects from L-theanine, and tea is considered safe to consume.
› In food
L-theanine is found in green and black tea leaves, as well as some types of mushrooms.
› Dietary supplements
You can find L-theanine supplements in capsule form or as part of green tea extract powders.
Source: Healthline, Psychology Today
Please consult your health care provider before making changes to your vitamin/supplement regimen.