Is Matcha Bad for You? Side Effects and How Much Is Safe per Day

Part of our Alpha GPC & NeuroMatcha guide library.

Matcha has a healthy reputation, but because you drink the whole ground leaf, you get more of everything in it, including caffeine. Here are the side effects worth knowing about, who should be careful, and how much matcha per day is reasonable.

What you'll learn

• Whether matcha is safe to drink every day
• The most common side effects, and why they happen
• Less obvious concerns: iron, liver, fluoride and contaminants
• How much matcha per day is reasonable, and who should limit it

Is matcha bad for you?

For most adults, no. No safety concerns have been reported for green tea consumed as a beverage by adults, although it does contain caffeine (NCCIH). The European Food Safety Authority also concluded that catechins from traditionally prepared green tea, and drinks with an equivalent composition, are generally safe at usual intakes (EFSA, 2018).

The risks are mostly about how much you have, who you are (pregnant, sensitive to caffeine, on certain medicines) and what form it comes in: a cup of matcha is very different from a concentrated green tea extract capsule.

Side effects of too much caffeine

Matcha has about 14 to 35 mg of caffeine per gram of powder (Meyer et al., 2023), so a strong habit can add up. Too much caffeine can cause (MedlinePlus):

• Restlessness and shakiness
• Trouble sleeping
• Headaches and dizziness
• A fast heart rate
• Anxiety
• Dehydration
• Dependency, needing more to get the same effect

Caffeine peaks within about an hour and can last 4 to 6 hours (MedlinePlus), and a typical cup of coffee should be finished at least 8.8 hours before bed to avoid losing sleep (Gardiner et al., 2023). For how matcha compares with coffee, see does matcha have caffeine?.

Stomach upset

Caffeine increases stomach acid, which can lead to an upset stomach or heartburn (MedlinePlus). Drinking matcha with food, using less powder, or switching the milk in a latte can help. For more, see does matcha make you poop?

Iron absorption

Polyphenols in tea can reduce how much non-heme iron (the kind in plant foods and fortified foods) you absorb from a meal. In typical diets that include vitamin C, meat, fish or poultry, this effect is largely offset (Zijp et al., 2000). If you are at risk of low iron, for example if you eat little meat or have heavy periods, have matcha between meals rather than with them, and pair iron-rich meals with vitamin C (Zijp et al., 2000).

Liver: a concern mainly with extracts

Liver injury has been reported in some people using green tea products, but uncommonly and mainly with green tea extracts in tablets or capsules (NCCIH). EFSA found that doses of 800 mg or more of EGCG a day taken as a supplement raised liver enzymes in clinical trials, while green tea drinkers typically get about 90 to 300 mg a day (EFSA, 2018). Rare liver reactions have also been reported with green tea drinks, most likely as idiosyncratic reactions (EFSA, 2018).

Matcha averages about 51 to 57 mg of EGCG per gram (Meyer et al., 2023), so you would need about 14 to 16 grams of powder a day, several times a normal amount, to reach 800 mg. If you also take a green tea extract supplement, count its EGCG too.

Fluoride and contaminants

Tea plants take up fluoride from the soil, and because you drink the whole leaf, matcha is a richer source than steeped tea. One study measured about 118 to 122 mg of fluoride per kilogram of matcha powder, which works out to roughly 0.24 mg in a 2-gram serving (Jakubczyk et al., 2022). That is a modest amount for most adults, but it is worth knowing if you drink a lot of matcha or tea every day.

Tea leaves can also contain trace metals such as lead and aluminum from the soil. With steeped tea, much of this stays behind in the leaves: in one study, levels in brewed black tea were far lower than in the dry leaves (Hamitoğlu et al., 2026). With matcha, nothing is left behind, so contaminant levels depend on where and how the tea is grown. We found no published study measuring lead in matcha drinks, so the practical step is to buy from brands that publish third-party testing for heavy metals.

Medication interactions

Green tea at high doses can lower blood levels of the beta-blocker nadolol, green tea extract can lower levels of the cholesterol medicine atorvastatin, and green tea has been shown to interact with raloxifene (NCCIH). Caffeine can also interact with stimulants, certain antibiotics, asthma medicines and heart medicines (MedlinePlus). If you take any of these, ask your pharmacist or provider about matcha.

How much matcha per day is safe?

There is no official limit for matcha itself, but two well-known thresholds give a useful frame: up to 400 mg of caffeine a day is not harmful for most people (MedlinePlus), and EGCG supplements at 800 mg a day or more raised liver enzymes (EFSA, 2018).

Estimates use 14 to 35 mg of caffeine and about 51 to 57 mg of EGCG per gram (Meyer et al., 2023); your matcha may differ. For most healthy adults, 1 to 3 servings a day keeps both well below those levels, as long as you count other caffeine too. Matcha blends contain less matcha per scoop: NeuroMatcha, for example, has 17.64 mg of caffeine per 2-tablespoon serving (Product Facts).

Who should limit or avoid matcha

• Pregnant people: keep caffeine moderate and ask your provider how much is right for you (NCCIH).
• Breastfeeding parents: high caffeine intake can make babies fussy and disturb their sleep, though low to moderate amounts usually do not cause problems (NCCIH).
• People with sleep problems, migraines, anxiety, GERD or ulcers, heart rhythm problems or high blood pressure should check with their provider about caffeine (MedlinePlus).
• People taking nadolol, atorvastatin, raloxifene or other medicines listed above (NCCIH; MedlinePlus).
• Children and teens: matcha contains caffeine, so ask a pediatrician before making it a habit.

Common myths (quick reality check)

• Myth: Matcha is so healthy that more is always better. Reality: Benefits in studies came from about 2 to 4 grams a day. More matcha means more caffeine and EGCG, not more benefit.

• Myth: Matcha has no side effects because it is natural. Reality: Its caffeine can cause jitters, poor sleep and an upset stomach, and it can reduce iron absorption from plant foods.

• Myth: Green tea extract pills are the same as drinking matcha. Reality: Liver problems have been linked mainly to concentrated extracts. A cup of matcha delivers far less EGCG than many extract supplements.

Frequently asked questions (FAQ)

Is matcha bad for you?

Not for most healthy adults in normal amounts. Its main side effects come from caffeine, such as jitters, poor sleep and an upset stomach. Concerns about the liver relate mainly to concentrated green tea extracts.

What are the side effects of matcha?

Mostly caffeine-related: restlessness, trouble sleeping, headaches, a fast heart rate, anxiety and stomach upset. Matcha can also reduce iron absorption from plant foods if you drink it with meals.

How much matcha per day is safe?

For most healthy adults, 1 to 3 servings a day (about 2 to 6 grams of powder) keeps caffeine and EGCG well below levels safety agencies flag. Count other caffeine, and have less if you are sensitive or pregnant.

Is it OK to drink matcha every day?

Yes, for most healthy adults. Daily matcha at normal amounts is in line with how people drink green tea, which has no reported safety concerns as a beverage for adults.

Is matcha bad for your liver?

Not at normal drink amounts. Rare liver injury has been linked mainly to green tea extract supplements, and EFSA flagged EGCG doses of 800 mg a day or more as supplements. That would take about 14 to 16 grams of matcha.

Does matcha block iron absorption?

It can reduce absorption of non-heme iron from a meal. If you are at risk of low iron, drink matcha between meals and pair iron-rich foods with vitamin C.

Can you drink matcha while pregnant?

Matcha contains caffeine, and NCCIH advises keeping caffeine moderate during pregnancy. Ask your provider how much is right for you.

Related guides

• Matcha benefits: what the research shows
• Does matcha have caffeine?
• Does matcha make you poop?
• Matcha vs coffee
• What is ceremonial grade matcha?

Disclaimer and when to seek help

This article is for general education and is not medical advice. These statements have not been evaluated by the Food and Drug Administration. Our products are not intended to diagnose, treat, cure, or prevent any disease. Talk to your health care provider if you are pregnant or breastfeeding, are sensitive to caffeine, have a medical condition, or take medication.

References

1. National Center for Complementary and Integrative Health. "Green Tea". Updated February 2025.
2. MedlinePlus (U.S. National Library of Medicine). "Caffeine".
3. EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS). "Scientific opinion on the safety of green tea catechins." EFSA Journal, 2018;16(4):e05239. doi:10.2903/j.efsa.2018.5239
4. Meyer BR, et al. "Catechin composition, phenolic content, and antioxidant properties of commercially-available bagged, gunpowder, and matcha green teas." Plant Foods for Human Nutrition, 2023;78(4):662-669. doi:10.1007/s11130-023-01121-2
5. Zijp IM, Korver O, Tijburg LB. "Effect of tea and other dietary factors on iron absorption." Critical Reviews in Food Science and Nutrition, 2000;40(5):371-398. doi:10.1080/10408690091189194
6. Jakubczyk K, et al. "Fluoride Content of Matcha Tea Depending on Leaf Harvest Time and Brewing Conditions." Nutrients, 2022;14(12):2550. doi:10.3390/nu14122550
7. Hamitoğlu M, et al. "Assessment of the Potential Health Risks Associated with the Toxic and Essential Elements Content in Tea Samples Marketed in Türkiye." Turkish Journal of Pharmaceutical Sciences, 2026;23(1):22-30. doi:10.4274/tjps.galenos.2026.86132
8. Gardiner C, et al. "The effect of caffeine on subsequent sleep: A systematic review and meta-analysis." Sleep Medicine Reviews, 2023;69:101764. doi:10.1016/j.smrv.2023.101764