Theanine Supplements

What L-theanine is

L-theanine is an amino acid found almost uniquely in tea leaves, and it's a big part of why a cup of green tea feels calming rather than just stimulating. It's associated with a "relaxed but alert" state — settled and focused rather than sedated — which is why people reach for it when they want to take the edge off without slowing down.

L-theanine and caffeine

This is the pairing L-theanine is best known for. Taken alongside caffeine, it tends to smooth out the jittery edge while keeping the alertness — the same balance nature strikes in green tea, which contains both. Plenty of people add it to their morning coffee for exactly that reason.

Forms and combinations

L-theanine comes here as capsules, chewables, and powders, in doses commonly from 100 mg to 250 mg. It also shows up in combination formulas — paired with magnesium or GABA for relaxation blends, for instance. You'll also see the branded Suntheanine form, a specific manufactured version of L-theanine.

L-theanine in Canada

L-theanine supplements sold in Canada carry a Natural Product Number (NPN) from Health Canada and ship from our Ontario warehouse to addresses across Canada.

Safety and side effects

L-theanine is generally well tolerated. Side effects are uncommon but can include mild headache or dizziness, and it may lower blood pressure slightly. If you're pregnant, taking medication, or managing a health condition, check with your healthcare provider before use.