The American Psychiatric Association says depression can affect one out of six people in their lifetime, which can cause emotional or physical symptoms that can dampen their work and family lives. According to Yale Medicine, depression can occur when neurotransmitters in the brain become disrupted, causing a loss of certain brain activity that can regulate your mood. Although combining counseling and medication can help treat depression, exercising, getting enough quality sleep, and avoiding alcohol are ways to improve your condition as well.
What you eat and drink can also affect depression, according to Harvard Medical School. Healthy diets like the Mediterranean diet which focuses on fruits, vegetables, and whole grains and limits sweets, refined and processed foods, and red meat are often associated with lower depression symptoms.
How about tea? We know that tea can fight inflammation and help protect against heart disease and some types of cancer, according to Penn Medicine. The flavonoids in green tea can also reduce cholesterol and blood pressure. Matcha, which is a tea powder made from ground green tea leaves, could have the antioxidant equivalent of 10 cups of infused green tea. But can this antioxidant-rich tea improve your mental health? A 2024 article in Nutrients says it has some potential.
Matcha reduces depression levels in mice
The study looked at the effects of matcha tea on two types of mice — one bred to handle stress and another more susceptible to stress. The researchers subjected both mice to isolation to induce a depressive state. When the stress-prone mice drank matcha tea, their depression levels went down. To find out more, the researchers looked at their brain activity and found that the stress-prone mice’s prefrontal cortex and nucleus accumbens were activated when they drank matcha tea. These parts of the brain control our dopamine levels, mood, and emotions, and people who are depressed tend to have less activity in these regions.
However, the researchers didn’t find this same effect on the stress-resilient mice. In other words, matcha tea was found to have varying effects according to the mice’s sensitivity to stress.
Researchers who weren’t involved with the study told Healthline that mice and humans are physiologically different and might not respond in the same way to matcha tea. There’s also a question of the proper dosage that would be required to treat depression since there’s little clinical evidence of its effect on humans. Additionally, depression has other causes than disrupted neurotransmitters, such as issues with hormones, the digestive system, genetics, and stress responses.
The health benefits of green tea
Green tea has various ingredients that can benefit your mental health. The first is epigallocatechin gallate, also known as EGCG. This polyphenol from green tea has potent cancer-fighting properties, according to a 2024 study in Nutrients. The caffeine in green tea can boost alertness, while L-theanine can enhance your mood by stimulating GABA, dopamine, and serotonin (via BBC Good Food). Theanine and arginine can reduce stress-related aging in the brain, according to a 2024 study in Molecules.
A 2024 study in Nutrients did a two-part investigation of green tea, with the first part involving mice and the second part involving humans. This study focused more on the ratio of caffeine and EGCG to theanine and arginine (called the CE/TA ratio), finding that higher levels of the first two substances can be more beneficial in reducing stress and brain inflammation. People drank 1.5 grams of matcha green tea three times a day while avoiding coffee and other types of tea. After just two weeks, the group drinking the higher CE/TA ratio reported lowered anxiety levels. Both groups who drank the matcha saw an improvement in their depressive tendencies. However, the people involved in the study were healthy adults, not people who were diagnosed with depression or anxiety.
