Matcha Side Effects: What You Need to Know

Matcha is safe when consumed in moderation.
Excessive amounts can lead to insomnia, restlessness, or digestive issues.
It can reduce iron absorption if drunk too close to mealtimes.
Max 2 to 3 cups per day, and never after 16:00-17:00.

1st possible side effect: is matcha tea a stimulant? Does it keep you from sleeping?

Like coffee, matcha tea contains theine, i.e. caffeine molecules bound to L-theanine, giving it a stimulating effect.

Thanks to the synergy of this combination, the energy provided by matcha lasts longer than that from a cup of coffee (about 3-4 hours). This makes it the ideal drink to start the day right and maintain good energy levels all morning long.

However, when consumed in excessive amounts, the caffeine in matcha can cause certain unpleasant side effects, such as:

an increase in blood pressure
intense restlessness
and even headaches.

So it's best not to overdo it! Despite a few discomforts, this side effect poses no real danger.

Also, if consumed late in the day or in excessive amounts, matcha tea can cause insomnia.

That's why I recommend never drinking matcha after 16:00 or 17:00, to make it easier to fall asleep and enjoy restorative sleep.

To learn more about the differences between coffee and matcha tea, I recommend reading my article on the subject.

Learn more: A Review of Scientific Research on Matcha Tea →: Welcome to our selection of relevant articles and features covering scientific and medical research on tea (green tea, black tea, white tea), with a particular focus on Japanese matcha green tea.

2nd possible side effect: can matcha tea cause constipation?

If you drink matcha in reasonable amounts, no.

In fact, green tea tends to have a diuretic and laxative effect, and helps support regular bowel movements. That's one of the many reasons it is often recommended for losing weight.

Consumed in excessive amounts, however, matcha can cause constipation: its caffeine concentration is dehydrating, which makes stools harder, leading to constipation.

If you already suffer from heartburn, green tea can also make the pain worse.

Watch out for bloating too: if you don't usually experience it, that's a sign you should limit your matcha tea consumption!

Learn more: Matcha and Digestion: What Are the Benefits? →

3rd possible side effect: does matcha tea interfere with proper iron absorption?

Yes, matcha interferes with the proper absorption of non-heme iron.

There are two types of iron: heme iron, found mainly in animal products, and non-heme iron, found in plants. While most of our iron intake comes from plant sources, non-heme iron is less well absorbed by the body than heme iron.

However, the tannins in tea bind to non-heme iron, preventing the body from absorbing it properly.

According to doctors, it is therefore recommended to drink tea at least 30 minutes before meals and 2 hours after meals, especially for people with iron deficiencies. If you suffer from anemia, your doctor may recommend stopping tea drinking until your iron levels return to normal.

Good to know: black teas contain the most tannins, so it is recommended to drink green or white tea instead to avoid poor iron absorption.

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Other possible side effects: what are the contraindications to drinking matcha?

There are no formal contraindications to consuming matcha.

However, I strongly recommend being vigilant in the following situations, which could pose a danger when large amounts of matcha are consumed:

During pregnancy or breastfeeding, be careful not to drink too many cups of matcha tea. A caffeine overdose can cause significant side effects on fetal growth, an increased heart rate in the baby, or a fragile and underweight baby at birth. The recommended amount of caffeinated drinks is two cups per day for a caffeine source — for a pregnant woman or breastfeeding mother.
Children are also more sensitive to caffeine than adults, so it is best not to give them more than one matcha tea per day.

What are the possible side effects of excessive matcha green tea consumption?

In short, excessive matcha consumption can cause the following symptoms:

intense restlessness, headaches
difficulty falling asleep, insomnia
constipation
stomach aches
pregnancy complications and fetal development issues
poor iron absorption, anemia

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In short, is there any danger in drinking matcha tea?

Matcha tea presents no real danger, as long as it is consumed in moderation. However, a few precautions can help avoid certain adverse effects, especially in sensitive individuals.

Here are the points to watch out for:

Caffeine: Excessive consumption can cause palpitations or anxiety. It is therefore advisable not to exceed 2 to 3 cups per day.
Tannins: They can cause nausea or limit iron absorption, especially if matcha is drunk on an empty stomach.
Liver: Very high consumption over the long term could put strain on the liver, but this remains rare and only occurs with excessive intake.

In short, matcha tea is not dangerous if enjoyed in moderation, while remaining attentive to its effects, especially for those sensitive to caffeine or tannins.

Why drink matcha tea anyway? Its benefits

As well as being delicious, matcha is a powerhouse of health benefits:

For the brain: Improves concentration, reduces mental fatigue, promotes a good mood, and supports cognitive function.
For the body: Protects cells from damage, strengthens the immune system, helps maintain a healthy weight, improves digestion, and supports cardiovascular health.
Other benefits: Hydrates, refreshes, tastes delicious, and may help maintain good oral health.

To learn more, read the article: 👉 All the benefits of matcha

In short, matcha is a versatile drink that offers a multitude of benefits for both body and mind.

Optimal matcha tea preparation to avoid side effects

Some of matcha's adverse effects can be avoided by paying attention to how it is prepared. The right method makes the drink easier to digest and more pleasant to taste. Here are some best practices to follow on how to properly prepare matcha tea:

Use water at the right temperature: Do not exceed 75-80°C to avoid burning the powder or releasing too many tannins.
Moderate dosage: 1 to 2 grams of powder (about 1/2 to 1 teaspoon) is enough for one serving.
Sift the powder: This prevents lumps, which can make matcha harder to digest.
Whisk gently: Using a bamboo whisk (chasen), make a "W" motion to achieve a light foam and a smoother texture.
Avoid overly sweet or milky additions: Some additions mask bitterness but can cause digestive discomfort if too rich.

Learn more: Matcha recipe: how to prepare good traditional matcha at home →: How to easily prepare matcha tea?A very common question I receive is "how do I prepare my matcha tea so that it has a creamy layer of foam like an espresso?" Here is my method for preparing a nice frothy and creamy matcha tea using Japanese utensils.

What other good practices should you adopt to avoid side effects?

To enjoy matcha's many health benefits without drawbacks, here are the best practices to follow:

drink up to 2 or 3 cups of matcha per day at most, for a healthy adult;
do not drink matcha tea after 16:00 or 17:00;
drink matcha tea 2 hours before or after meals.

I hope the side effects of matcha tea no longer hold any secrets for you, and above all that you now know how to avoid them.

But in moderation, mindfully and serenely, a delicious quality matcha tea is ideal to incorporate into your daily routine as part of a healthy lifestyle.

I invite you to discover one of my best matcha green teas, the organic ultra-premium matcha, as well as my community's favorite, the organic Saemidori matcha, and explore this antioxidant-rich green tea!

Image de l'article : Quels sont les effets secondaires possibles du thé matcha ?

FAQ: your questions about the side effects of matcha tea

Can you drink matcha on an empty stomach?

It is not recommended to drink matcha on an empty stomach, as its caffeine and tannins can irritate the stomach. It is best consumed after a light meal.

Is matcha discouraged during pregnancy?

Due to its caffeine content, matcha should be consumed in moderation during pregnancy. It is best to seek advice from a healthcare professional.

How much matcha per day is safe?

For a healthy adult, 1 to 2 servings per day is enough. That corresponds to about 2 grams per serving, the caffeine equivalent of 1 to 2 coffees.

Do the effects differ depending on the quality of the matcha?

Yes. A higher-quality matcha (such as ceremonial-grade matcha) is often better tolerated than lower-quality powders (with an attractive price), which are sometimes more bitter or less well sifted.

Does matcha slim have dangerous side effects?

Matcha slim can cause side effects such as sleep disturbances or digestive discomfort, especially when overconsumed. To learn more about its composition and effectiveness, check out our full article: matcha slim reviews. Note that matcha slim contains only a small amount of matcha powder and is not sold by Kumiko Matcha.

Click here to discover my full range of organic matcha teas that are good for your health