Health & Caffeine

Benefits, caffeine, and safety.

Can I drink matcha every day?

One or two servings a day sits inside the published reference points: a 2g serving carries about 38-89mg of caffeine against the 400mg a day FDA and EFSA cite for healthy adults, and about 105mg of EGCG against the nearest derived beverage level of 704mg. The longest direct trial ran 2g a day for 12 months in 99 older adults and reported no harm attributed to matcha. The quantity worth tracking is lead: roughly 0.13-0.6 µg per serving, small against the 1.7-4.8 µg a day US adults already get from food, but at or around California's 0.5 µg/day Prop 65 level on every day you drink it.
How much caffeine is in matcha?

Matcha's caffeine tracks the powder, not the cup: roughly 19-44mg per gram, so a standard 2g serving (about one level teaspoon) is about 38-89mg, most often around 60-70mg. That is under an 8oz coffee at 80-100mg, though a 3-4g preparation can pass it. The L-theanine in matcha is why the same caffeine can feel calmer — not slower.
Is there lead in matcha? What about heavy metals?

Matcha contains trace lead, as all tea grown in soil does — and because you drink the whole leaf, origin and testing matter more than they do with steeped tea. Japanese matcha measures at the low end: roughly 0.13–0.6 µg of lead per 2 g serving, against the 1.7–4.8 µg a day an average US adult already gets from food. But no safe level of lead has been established, and that same serving can cross California's Prop 65 warning level, which is why tins carry warnings.
Matcha vs coffee: What's actually different?

Matcha's caffeine tracks the powder: a 2g serving is about 38-89mg, most often around 60-70mg, against 80-100mg for an 8oz coffee. The 'slow release' claim has no pharmacokinetic support — caffeine from either drink is about 99% absorbed within 45 minutes. L-theanine, which coffee has none of, is the best available explanation for the calmer feel, but no trial has compared the two drinks.
Why does matcha give you calm energy?

Caffeine and L-theanine together do measurably improve attention in the first couple of hours — two meta-analyses agree. But a matcha serving delivers study-level caffeine and below-study-level L-theanine, so your bowl runs the opposite ratio to every trial that produced the finding. The 'calm' half is the least measured part of the claim.
Why does matcha make me nauseous?

No trial, cohort or case series has studied matcha and nausea, so everything below is transferred from green tea extract research and beverage chemistry. The step with the most behind it is eating first: free EGCG peaked more than 3.5-fold higher fasting than fed in healthy volunteers, and the nausea those trials recorded clustered in the fasting condition — at capsule doses seven to eleven times the 105.3mg of EGCG in a 2g serving. Using less powder lowers everything proportionally. The explanation you'll see everywhere — that matcha's caffeine stimulates stomach acid — does not survive its own source paper: caffeine drunk as a solution delayed gastric acid secretion, and only encapsulated caffeine stimulated it. Severe or persistent symptoms are worth taking to a doctor.