Short answer: Yes, you can drink too much green tea. Consuming large amounts can cause side effects mainly due to caffeine and tannins, and in some cases may interfere with iron absorption and interact with medications. Key points to consider
- Caffeine-related effects: High intake can trigger jitters, anxiety, sleep disturbances, upset stomach, headaches, and increased heart rate or blood pressure in sensitive individuals. If caffeine sensitivity is present, even moderate consumption can be problematic for sleep or nerves [web results indicate common caffeine-related side effects].
- Iron absorption: Green tea polyphenols and tannins can inhibit iron absorption from meals, which may contribute to iron-deficiency anemia in people with low iron stores, pregnant individuals, vegetarians/vegans, or those with restricted diets. Avoid drinking large amounts of green tea right after meals if iron status is a concern [web results discuss iron absorption interference].
- Digestive and other effects: Excessive consumption can cause nausea, stomach upset, constipation or diarrhea, mouth dryness from tannins, and dehydration if fluids are lost through diarrhea or frequent urination. Very high intake may disrupt electrolyte balance or kidney function in some cases [web results mention these potential issues].
- Medication interactions: Green tea can interact with certain drugs (such as blood thinners, beta-blockers, or some cholesterol medications). If taking prescription meds, check with a healthcare provider before significantly increasing green tea intake [web results note possible interactions].
- Practical guidance: For many people, 3–4 cups per day is a common upper practical limit; beyond that, consider individual tolerance, iron status, sleep quality, and any medical conditions. Some sources suggest that a small portion of the population could tolerate more, but this is not a universal recommendation. If iron deficiency or caffeine sensitivity is a concern, limiting intake further or timing it away from meals and bedtime may help [web results provide these general guidelines].
If you’d like, I can tailor guidance to your situation (e.g., if you’re pregnant, have iron-deficiency anemia, take specific medications, or have sleep issues).
