Green tea contains caffeine, which can disrupt sleep patterns and lead to insomnia, especially if consumed in large quantities or close to bedtime.
Drinking too much green tea can cause stomach irritation, nausea, or acid reflux due to its caffeine and tannin content, which can increase stomach acidity.
The tannins in green tea can inhibit iron absorption, potentially leading to iron deficiency or anaemia if consumed in excessive amounts, particularly in people with existing iron deficiencies.
Excessive caffeine intake from green tea can trigger headaches or migraines in sensitive individuals or those who consume large quantities.
Excessive green tea consumption can lead to decreased calcium absorption, potentially affecting bone health and increasing the risk of osteoporosis over time.