Table of ContentsView AllTable of ContentsWhat Is L-Theanine?What Is Magnesium?Synergy and Combined BenefitsDosageSide Effects and Precautions
Table of ContentsView All
View All
Table of Contents
What Is L-Theanine?
What Is Magnesium?
Synergy and Combined Benefits
Dosage
Side Effects and Precautions
L-theanine and magnesium are individual supplements that are growing in popularity.
L-theanine is commonly used for sleep issues andstress,while magnesium has a wide range of uses, includingmood disordersand heart conditions.
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.
This article explains the effects of these supplements on anxiety symptoms, whether combining them is beneficial, and safety precautions to consider.
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L-theanineis the primary amino acid found in tea leaves.It helps give tea its distinct caramel flavor and counteracts its caffeine’s bitterness.L-theanine is also found in some mushrooms.
How It Works
L-theanine interacts withneurotransmitters(chemical messengers) to produce a relaxed but focused state.Specifically, it helps releasegamma-aminobutyric acid (GABA), an amino acid that regulates the body’sdopamineandserotoninlevels.
Health Benefits
It’s been studied for various health benefits. Some of these include the following:
Before you stock up on L-theanine, remember that larger, long-term studies into these effects are still necessary.
Could This Supplement Combo Be Your Secret to Less Stress and Anxiety?
Magnesium is an important mineral for overall health. It’s involved in more than 300 reactions in the body, and plays a role in processes like the following:
Where Can I Get It?
Magnesium can be consumed in the diet or taken as a dietary supplement. Magnesium-rich foods are also generally high in fiber. These include:
Of note, more than two out of three people in the U.S. do not get the recommended daily amount of magnesium from their diet.Low levels of magnesium have been linked to conditions likedepression,anxiety, andtype 2 diabetes.
Magnesium is available as asupplementin various forms, including:
Potential health benefits of magnesium include, but are not limited to:
Magnesium is primarily absorbed in thesmall intestine.For this reason, some conditions that affect the gastrointestinal tract interfere with magnesium absorption. Some examples of these conditions are:
Magnesium-Nutrient Interactions
Magnesium can interact with some other nutrients. Taking very large doses ofcalciumcan cause magnesium levels to decrease.Taking specific forms ofvitamin Dcanincrease magnesium absorption.Taking high doses ofzinccan keep magnesium from getting absorbed into the body.
In medicine, synergy is a term for what can happen when two drugs that act similarly in the body produce a much greater effect than expected. For example, some cancer medications and antibiotics act synergistically when taken together.Drugs with synergy produce a super effect that may allow for smaller doses.
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.
A combination study compared the effects of L-theanine alone to a combination of L-theanine plus magnesium in mice.It showed that taking the combination product significantly benefited sleep quality. L-theanine plus magnesium reduced the time it took to fall asleep and increased the length of sleep more than either supplement alone. The combination produced more delta waves in the brain, which are associated with deep sleep.
Importantly, this study has a big caveat. Effects seen in animals may or may not translate into benefits for humans, so trials in people are certainly necessary.
Another combination study explored the effects of a product containing L-theanine, magnesium,B vitamins, andrhodiola.This combination was given to chronically stressed but otherwise healthy people. Their anxiety symptoms were modestly reduced within two weeks. More research is necessary before this product or its individual components can be routinely recommended.
L-Theanine Dosage
L-theanine has been studied in clinical trials at the following dosages:
For comparison, one cup ofgreen teacontains 8 to 30 mg of L-theanine.
There’s little evidence of drug interactions with l-theanine. However, because it acts on the GABA receptors, it could enhance the effects of other medicines with similar actions. Some examples include other sedating medicines like barbiturates andbenzodiazepines.
Magnesium Dosage
The Food and Nutrition Board (FNB) at the Institute of Medicine of the National Academies recommends a daily intake of magnesium for adults and children. For adults, the recommended intake is between 310 and 420 mg of elemental magnesium daily, depending on gender and pregnancy status.
Remember that any combination of diet and supplements can meet this magnesium goal. If you take a magnesium supplement, keep in mind that the maximum dose for adults is 350 mg per day.
Magnesium-Medication Interactions
Othermedicines can affect magnesium levels. Some that can increase magnesium levels include:
Many medications decrease levels of magnesium. Some examples include the following:
The U.S. Food and Drug Administration (FDA) has classified L-theanine as generally recognized as safe (GRAS).At normal doses, it’s not associated with side effects.
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.
Potential side effects that may occur with very high doses of magnesium include:
Consult your healthcare provider, pharmacist, or registered dietitian nutritionist before starting any new supplement regimen.
The best time of day to take an L-theanine or magnesium supplement may depend on why you’re taking it. Try taking L-theanine at bedtime to promote quality sleep or during the day for anxiety symptoms.It’s not known to cause daytime drowsiness.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements like prescription drugs. This means some supplement products may not contain what the label says. Whenchoosing a supplement, look for indepenently tested products and consult a healthcare provider, registered dietitian nutritionist (RDN or RD), or pharmacist.
Summary
There’s some evidence that both L-theanine and magnesium supplements can help regulate sleep and anxiety symptoms.
Some people take them together to enhance the effects, but there is no evidence from human trials to validate this.
If you are struggling with sleep issues or stress symptoms, discuss your goals with your healthcare provider for individualized recommendations that can help.
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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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