Matcha green tea powder is one of the healthiest items on the planet. It includes a wide range of benefits to your health. However, its high caffeine content can result in certain side effects. This mainly applies to people who are not accustomed to consuming caffeine products on a daily basis. Possible side effects of drinking matcha green tea include diarrhea, sleeplessness, dehydration and nausea. It is important to keep in mind that you need to start drinking matcha in low doses. Then as your body gets used to matcha and you no longer feel any ill effects you can start drinking more. It is advisable to start with 1 sachet in 1 litre water. Once your body starts accepting matcha tea you can increase the dosage to 1 sachet in 250 ml water.