Matcha side effects can include jitters, sleep disruption, reflux, or nausea, especially on an empty stomach or at high caffeine doses. Most side effects depend on how much you drink, when you drink it, and your personal sensitivity to caffeine.
- Jitters, anxiety, or feeling wired
- Trouble sleeping (especially if you drink it later in the day)
- Heartburn or reflux in sensitive people
- Nausea or an upset stomach, often on an empty stomach
- Needing to poop quickly, or loose stools for some people
- Headaches (often from too much caffeine or dehydration)
- Reduced iron absorption if taken with iron-rich meals or supplements
- More sugar and calories if you use sweetened “matcha” mixes
These side effects are not guaranteed. Most depend on dose, timing, and your personal sensitivity to caffeine. For many people, matcha is a gentle daily drink, but it helps to know what to watch for and how to make it easier on your body.
What you'll learn:
Are there side effects to matcha?
Yes, there can be. Matcha is still tea, but it is a more concentrated format because you are drinking the whole leaf as a powder.
Most matcha tea side effects come from three things: caffeine, stomach sensitivity, and timing (especially around sleep and iron-rich meals). If you want the basics of what matcha is and why it behaves differently to brewed green tea, start with what is matcha.
We sell matcha, so we want to be upfront: here is what the independent research says. If you want the evidence-focused view of matcha’s upsides (with sources), read matcha benefits.
Caffeine-related matcha side effects (jitters, anxiety, sleep, heartburn)
Matcha contains caffeine. If you are caffeine-sensitive, matcha can cause the same issues coffee can, including jitters, a racing feeling, irritability, and trouble sleeping.
Even if you feel “fine”, caffeine later in the day can quietly reduce sleep quality. For exact caffeine ranges and comparisons, see does matcha have caffeine.
Some people describe matcha as “calmer” than coffee. That can happen, but it is not a guarantee. If you are anxious or wired after matcha, the simplest explanation is still dose. Less powder usually helps more than switching milk or adding sweeteners.
Heartburn is another common complaint. Caffeine can relax the lower oesophageal sphincter in some people, which may make reflux worse. If matcha triggers reflux for you, try a smaller serving, have it with food, and avoid drinking it too hot or too quickly.
Stomach and digestion effects (nausea, upset stomach, poop changes)
Some people feel nauseous after matcha, especially if they drink it on an empty stomach. Matcha is “green” and concentrated, and some bodies just do not love that first thing in the morning.
Matcha can also change bathroom timing. For some people it causes a quicker urge to poop, while others notice no change at all. The main reasons are caffeine, warm liquid, and routine. This post breaks it down: does matcha make you poop.
If your stomach feels off, it can help to slow down. Drinking a strong matcha quickly, especially before food, is a common way to trigger nausea. A smaller serving and a slower sip often fixes it.
If matcha upsets your stomach, the first fixes are simple: have it with food, use less powder, and drink it more slowly.
Matcha and iron absorption (timing matters)
Tea polyphenols can reduce absorption of non-haem iron (the type found in plant foods and supplements), especially when tea is consumed with meals. This does not mean matcha “causes iron deficiency”, but timing can matter if you are already low on iron.
If you have iron deficiency, heavy periods, follow a plant-based diet, are pregnant, or you take iron supplements, the simplest approach is spacing matcha away from iron-rich meals and supplements. For the detailed timing guide, read matcha and iron absorption.
This question comes up a lot for women in particular because iron status can already be harder to maintain with heavy periods. If you want the wider context, see matcha benefits for women.
How much matcha is “too much”?
There is no one perfect number for everyone. It depends on how much matcha you use per drink, how much other caffeine you have (coffee, tea, energy drinks), and how your body responds.
A lot of people run into problems because they accidentally double the dose, for example using two heaped teaspoons, making multiple strong lattes, or drinking matcha late in the day. If you want a practical daily range and how to think about serving size, see how much matcha per day.
If you are drinking matcha for appetite control or weight loss, it is easy to overdo it. Matcha can be a helpful swap for sugary drinks, but it should not become a “more is better” habit. This guide keeps it realistic: is matcha good for weight loss.
Interactions and higher-risk situations
If you are pregnant, breastfeeding, have a heart condition, have reflux that is hard to control, have diagnosed iron deficiency, or take medication, it is sensible to be cautious with caffeine and ask a clinician if you are unsure.
Matcha as a drink is different from concentrated green tea extract supplements. Supplements can deliver much higher doses of compounds than a normal cup, and the safety profile is not the same. If you use supplements, it is worth checking the label and speaking with a clinician.
How to reduce matcha side effects (simple, practical steps)
Most side effects improve with a few small changes. You do not need to quit matcha to make it work for you.
- Start small: begin with about 1g matcha and see how you feel, then increase only if you want to.
- Have it with food: this is one of the easiest ways to reduce nausea and jitters.
- Keep it earlier in the day: caffeine timing matters more than people think.
- Watch added sugar: sweetened mixes and syrups can make you feel worse. If you want the calorie side, see matcha calories.
- Space it around iron: if you are managing iron, use timing rather than panic. See matcha and iron absorption.
- Stay hydrated: dehydration can make headaches and jitters more likely.
If matcha still does not sit well with you, it may simply not be your drink. That is okay. Many people do better with a smaller serving, or with an occasional latte rather than a strong daily matcha.
Related reading
Frequently Asked Questions
What are the side effects of matcha tea?
The most common side effects are caffeine-related (jitters, anxiety, sleep issues) and stomach-related (nausea, upset stomach). They are more likely with larger servings, on an empty stomach, or later in the day.
Can matcha cause headaches?
It can for some people, usually from too much caffeine or dehydration. If you get headaches, try a smaller serving and drink water alongside it.
Is it bad to drink matcha on an empty stomach?
For some people it is fine, but many people feel nauseous with matcha on an empty stomach. If that happens to you, have it after breakfast or with a snack.
Can matcha cause anxiety?
It can if you are sensitive to caffeine. Start with a smaller serving, avoid drinking it late in the day, and reduce other caffeine sources if anxiety is an issue.
Who should avoid matcha?
People who are very caffeine-sensitive, have certain heart conditions, have uncontrolled reflux, or have diagnosed iron deficiency may need to be cautious. If you are pregnant, breastfeeding, or take medication, it is sensible to check with a clinician.
Is matcha bad for you?
Not for most people when used in sensible amounts. Problems usually come from too much caffeine, strong servings on an empty stomach, or drinking it too late in the day.
Try a gentler matcha
If matcha does not sit well with you, start small and focus on quality, many harsh reactions come from too much, too strong, or sweetened mixes. You can try a smooth matcha powder, measure your serving, and adjust slowly until it feels good.
Sources
- NCCIH: Green Tea (Usefulness and Safety)
- EFSA Scientific Opinion: Safety of caffeine (2015)
- NIH Office of Dietary Supplements: Iron (Fact Sheet for Health Professionals)
- Haskell CF, et al. The combined effects of L-theanine and caffeine on cognitive performance and mood (2008)
- EFSA Scientific Opinion: Safety of green tea catechins (2018)
Written by the Popcha team. Last updated: February 2026.