These two supplements may complement each other’s effects on anxiety and other indications in a process called synergy.
Synergy means that the effect of taking both products together is greater than the effect of taking them separately.
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What Is L-Theanine?

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Health Benefits
It’s been studied for various health benefits.
What Is Magnesium?
Magnesium is an important mineral for overall health.
Magnesium can be consumed in the diet or taken as a dietary supplement.Magnesium-rich foodsare also generally high in fiber.
Some examples of these conditions are:
Magnesium-Nutrient Interactions
Magnesium can interact with some other nutrients.
In theory, L-theanine and magnesium have potential synergistic effects when taken together.
But so far, there’s not much high quality evidence to prove it.
The combination produced more delta waves in the brain, which are associated with deep sleep.
Importantly, this study has a big caveat.
Their anxiety symptoms were modestly reduced within two weeks.
More research is necessary before this product or its individual components can be routinely recommended.
No supplement is intended to treat, cure, or prevent disease.
There’s little evidence of drug interactions with l-theanine.
Some examples include other sedating medicines like barbiturates andbenzodiazepines.
Remember that any combination of diet and supplements can meet this magnesium goal.
Magnesium-Medication Interactions
Othermedicines can affect magnesium levels.
Some that can increase magnesium levels include:
Many medications decrease levels of magnesium.
That said, side effects are always possible when taking a medication or supplement.
If you notice anything unusual, be sure to keep your healthcare provider informed.
Though magnesium from the diet is unlikely to cause side effects, avoid taking high doses of magnesium supplements.
This means some supplement products may not contain what the label says.
Published 2022 Apr 5. doi:10.3389/fnut.2022.874254
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