L-Theanine for Weight Loss: Does It Work?

L-theanine has been found to have anti-stress and mood effects, but is there any evidence that it can aid in weight loss? In this review of the research on L-Theanine for weight loss, we find what does work.

L-Theanine for Weight Loss: Does It Work?. L-Theanine is a supplement that has been used to help people lose weight, but does it work?.

L-Theanine for Weight Loss: Does It Work?

If you’re acquainted with L-theanine, it’s likely that you first heard about it in relation to improving cognitive function.

Perhaps you’ve heard that L-theanine can help you sleep better.

L-theanine is often described primarily as a cognitive compound—one that you take to either relax or quietly improve your attention, particularly when combined with caffeine’s focus-enhancing properties.

But, like green tea in general, L-theanine, an amino derived from Camellia sinensis (green tea leaves), seems to have considerable weight-loss benefits.

Surprisingly, despite its restricted reputation as a cognitive enhancer, L-theanine may also help you lose weight by reducing extra body fat and changing your relationship with food.

While L-main theanine’s health and fitness benefits occur mostly in the central nervous system (CNS), the indirect health and fitness impacts of L-neuronal theanine’s activity may provide considerable benefits for athletes and exercisers seeking a leaner, more cut body.

But, in order to comprehend how L-theanine does so much, we must first comprehend what this nootropic amino acid is all about. So, let’s start from the beginning: What is L-theanine, exactly?

What is L-Theanine, exactly?

L-theanine is an amino acid found in the leaves of the Camellia sinensis plant, which is used to make most types of tea, including green, white, and black. L-theanine is a bioactive component of Camellia sinensis that contributes to the soothing and relaxing effects of, example, a hot cup of green tea.

This is why, despite its caffeine content, green tea is considered “relaxing,” as opposed to a cup of coffee, which has caffeine but no L-theanine.

The structural similarities between L-theanine and the neurotransmitters glutamine and glutamate seem to be responsible for its nootropic properties. 1 An estimated 24 mg L-theanine may be found in a regular 200 mg cup of black tea, compared to 8 mg L-theanine in a 200 mg cup of green tea. 2 

However, it’s recommended that you take an L-theanine supplement with 100 mg or more per dose to fully enjoy the nootropic advantages (and fat reduction benefits, as we’ll discuss momentarily).

List of L-Nootropic Theanine’s Benefits

L-theanine is unique in that it seems to quiet cognition without sedating it. Despite the fact that it does not sedate cognition, L-theanine seems to improve sleep quality.

L-theanine is thought to provide such contradicting nootropic advantages by strengthening alpha brainwave frequencies throughout your brain activity, rather than flooding your brain with extra “manufactured” neurochemical activity, as many smart medication cognitive enhancers do. 3

Alpha brainwaves are associated with peaceful, creative, meditative thinking. They put you in a cognitive “flow state”—like you’re “in the zone”—totally calm and collected while remaining focused on the work at hand.

L-key theanine’s nootropic properties include:

  • Improved concentration and focus
  • Reduced anxiety and stress
  • Better sleep quality
  • Improved motivation and mood
  • Improved memory and cognition linked to tasks

Yes, L-theanine may help with fat reduction in addition to improving cognitive.

Does L-Theanine Help You Lose Weight?

Green tea extract, with its high concentration of antioxidant catechins (most notably epigallocatechins-3-gallate, or EGCG), is well-known for its health and fitness benefits, particularly in terms of cardiometabolic and weight control. 4

However, L-theanine, a component of green tea, does not have the same level of popularity as a weight-loss supplement. Perhaps because catechins, rather than L-theanine alone, may have a bigger influence on weight management.

Regardless, L-theanine seems to help with fat reduction, particularly when combined with a powerful green tea extract.

While the catechin content of green tea receives the majority of the focus when it comes to fat reduction, L-theanine may have a role in green tea’s weight loss advantages.

Weight Loss Benefits of L-Theanine

L-theanine may provide considerable fat-burning benefits connected to exercise due to the interaction between psychological mood and physical energy production.

The nootropic chemical, on the other hand, seems to have more immediate weight-loss effects that don’t completely overlap with the amino’s cognitive-enhancing goals.

With this in mind, L-theanine might help you lose weight by aiding with:

Regulation of Appetite

Stress eating is a legitimate phenomena connected to the body’s increased desire for high-fat, energy-dense meals during times of prolonged stress, despite being a rather amusing meme these days.

While appetite diminishes under acute stress, chronic stress amplifies the appetite to an excessive degree,5 which perhaps explains why stress-relieving L-theanine has been associated with Regulation of Appetite.6

A group of researchers noticed the anti-obesity benefits of three primary components of green tea (catechins, caffeine, and theanine) in animal (mice) studies. “At least caffeine and theanine were responsible for the suppressive impact of green tea powder (GTP) on body weight rise and fat formation,” the researchers concluded based on their results. 7

Metabolism of Dietary Energy

L-theanine in conjunction with caffeine, as reported in a previous research, may have a suppressive impact on body weight gain and fat storage. Another animal research found that mice given a normal diet, a high-fat diet (HFD), a high-fat diet with green tea (GT) containing L-theanine and caffeine, or a high-fat diet with catechins had similar results.

The HFD with theanine-and-caffeine-rich GT was demonstrated to minimize the fat-building effects of the HFD at the conclusion of the research. “Obese mice revealed abnormalities related with aberrant lipid and energy metabolism, which were eased by GT ingestion, revealing the mechanism underlying the anti-obesity actions of GT,” the researchers concluded. 8

Fat Loss from Sleep

You’re eating well and exercising regularly, but you’re not getting the weight reduction results you’d hoped for. It’s likely that you haven’t addressed another important part of good weight management: sleep.

It’s common knowledge that not getting enough sleep makes it difficult to lose weight. “The quantity of human sleep helps to the preservation of fat-free body mass during times of low calorie consumption,” according to a 2011 research. 9

This implies that when “dieting” (or “reducing energy intake”), sleep is crucial to the diet’s success.

L-theanine helps with one of the important variables in healthy weight loss—not to mention healthy lean muscle gains—as a safe and effective promoter of sleep quality. 10

Boost Fat Loss with L-Theanine and Caffeine

Obviously, you don’t want to combine L-theanine with caffeine immediately before night if you want to improve your sleep quality and lose weight. During the day, however, the well-known L-theanine + caffeine stack is a successful method for:

  1. Boost Cognitive Performance Immediately
  2. Boost Thermogenesis (Calorie Burning)

Many individuals would want to reduce their caffeine consumption, but few would wish to completely remove caffeine from their diet. Simply put, it tastes too wonderful, and there’s no doubting the health and fitness advantages of a little caffeine.

This is one of the reasons why the L-theanine + caffeine combination is gaining popularity among today’s health and fitness enthusiasts: by “smoothing out” the caffeine experience, L-theanine helps maintain the stimulant’s energy-boosting and attention-promoting benefits while reducing the jittery edge.

In fact, it seems that L-theanine and caffeine operate better together than they do alone.

Clinical research also suggests that “L-theanine and caffeine in combination are beneficial for improving performance on cognitive demanding tasks,” in addition to much of the research mentioned earlier that pinpoints L-fat-burning theanine’s benefits in general on the L-theanine + caffeine combination. 11

This implies you may use L-theanine + caffeine to increase your working performance as well as enhance your thermogenic calorie-burning ability during exercise.

Take L-theanine with caffeine at a 2:1 L-theanine to caffeine ratio for optimal benefits—for example, 100mg L-theanine, 50mg caffeine.

Suntheanine® is the best L-Theanine for weight loss.

L-theanine is present. Suntheanine® is a 100 percent pure, nature-identical L-theanine brand that has been scientifically shown to enhance stress-related symptoms, attention, and other cognitive performance indicators. 12 

Suntheanine® is so pure that 100mg of it provides the L-theanine equivalent of 10 cups of green tea.

Look for L-theanine as Suntheanine®, which is utilized in the L-theanine-containing Stimulation by Performance Lab® mix, for maximum fat-burning and brain-boosting advantages.

Stimulation by Performance Lab®


Powered by L-theanine + natural caffeine (and more), Stimulation by Performance Lab® is an ultramodern “Caffeine 2.0” stimulation stack designed for peak caffeine-driven thermogenesis and performance boosts minus the expected post-energy “comedown” and “crash” associated with stimulant use.

Taken first thing in the morning, midway through your work shift, before exercise, or whenever you need it, Stimulation by Performance Lab® can help you stay energized and metabolically active throughout the day without compromising your sleep quality and cognitive composure.

Stim’s unique range of all-natural nootropics is to thank for it.


  • 50mg natural caffeine (derived from Coffea robusta seeds)
  • 100mg Suntheanine® L-Theanine
  • 250mg Ajipure® L-Tyrosine
  • Caffeine Balance B-Complex NutriGenesis®:
    • 500mcg Riboflavin+ (Vitamin B2)
    • 750 mg vitamin B6+
    • 167 mcg DFE Folate+ (Vitamin B9)
    • 2 mg vitamin B12+

The future of caffeine stimulation, Stimulation by Performance Lab® advances the traditional “caffeine pill” formula with natural nootropics and a minimally effective dose of caffeine that actually delivers upon the stimulant’s energy and focus boosting benefits without the usual jittery side effects.

Altogether, Stimulation by Performance Lab®’s stack splits into the following two sub-stacks:

#1 – Performance-Tuned Stimulation: this is the L-theanine + caffeine combination, a fat-burning nootropic duo that has been shown in clinical studies to improve attention, concentration, and alertness by combining caffeine’s stimulatory advantages with L-mood-boosting theanine’s relaxing effects.

#2 – Caffeine Balance and Recovery: Stim combines pro-catecholamine L-tyrosine (as premium Ajipure®) with a bioavailability-enhanced B-complex (as NutriGenesis®) to counterbalance caffeine’s increased neurochemical demands on the CNS.

Stim’s formula is delivered in all-natural, plant-based NutriCaps®, a proprietary capsule made of fermented tapioca (pullulan) that is free of any synthetics or artificial additives, matching the naturalness of its constituents. Here is just pure, green thermogenesis.

Key Advantages

The primary health and fitness benefits of Stimulation by Performance Lab® fall under the following performance categories:

  • Stim uses a combination of caffeine stimulation and natural nootropic brainpower to boost alertness, mood, memory, attention, energy, and vitality.
  • Caffeine (added by Stim’s nootropics) boosts intensity, endurance, and both physical and competitive fitness in athletes.
  • Caffeine increases calorie-burning metabolic performance for greater fat reduction and weight control when combined with B-vitamins and L-tyrosine.

While the L-theanine + caffeine duo here helps with thermogenic fat loss, the full Stimulation by Performance Lab® formula assists with multiple aspects of physical and mental health and fitness.

Stim provides a scalable supply of caffeine, with a moderate 50mg natural caffeine per serving that may be taken as needed depending on your unique caffeine tolerance and stimulatory demands.

Get the Best Deal on Stimulation by Performance Lab® Here.

Conclusion: Does L-Theanine Help You Lose Weight?

L-theanine is effective whether you want to increase your cognitive ability, lose weight, sleep better, or do all of the above. Few (if any) natural nootropics have as many multifunctional purposes and advantages as this one.

While L-theanine alone is a good option for improving mood and attention, this supplement works especially well when combined with other components, such as caffeine.

This means that simply adding L-theanine to your morning routine with your morning coffee, or taking a complete, complex formula like Stimulation by Performance Lab®, will help you get more out of your day.

The bottom line: L-theanine is one of the greatest natural supplements you can add to your daily routine for an instant boost in performance and long-term weight, health, and fitness changes.



  1. The neuropharmacology of L-theanine (N-ethyl-L-glutamine): a potential neuroprotective and cognitive-enhancing drug, Nathan PJ et al. 2006; 6(2): 21-30 in J Herb Pharmacother.
  2. EK Keenan and colleagues In a cup of tea, how much theanine is there? Effects of tea kind and preparation technique. Food Chemistry, 125(2), 588-594, March 15, 2011.
  3. L-theanine, a natural component of tea, and its influence on mental state, Nobre AC et al. Asia 17 Suppl 1: 167-8, Pacific Journal of Clinical Nutrition, 2008.
  4. T Nagao and colleagues In humans, a high-catechin green tea extract decreases body fat and cardiovascular risks. Obesity (Silver Spring) 15(6): 1473-83 in 2007.
  5. Stress, cortisol, and other appetite-related hormones: Prospective prediction of 6-month changes in food desires and body weight, Chao AM et al. Obesity (Silver Spring). 2017 Apr; 25(4): 713-720.
  6. Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial, Hidese S and colleagues. Nutrients, 11(10), 2362, October 2019.
  7. Green tea catechins, caffeine, and theanine have anti-obesity benefits in mice, according to Zheng et al. Jan-Feb 2004; 18(1): 55-62 in In Vivo.
  8. Green tea alters blood and liver metabolic profiles in mice with obesity caused by a high-fat diet. Lee LS et al. 2015 Apr; 59(4): 784-94 in Mol Nutr Food Res.
  9. Insufficient sleep impairs nutritional attempts to decrease adiposity, according to Nedeltcheva AV et al. 435-441 in Ann Intern Med, October 5, 2010.
  10. GABA and L-theanine combination reduces sleep latency and enhances NREM sleep, according to Kim S et al. 57(1): 65-73 in Pharm Biol.
  11. The combined effects of L-theanine and caffeine on cognitive function and mood, Owen GN et al. 2008 Aug; 11(4): 193-8 in Nutr Neurosci.
  12. MR Lyon and colleagues A randomized, double-blind, placebo-controlled clinical study of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD). Altern Med Rev. 16(4): 348-54, December 2011.

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“L-Theanine for Weight Loss: Does It Work?” is a question that has been asked by many people. The answer to the question is “yes.” Reference: does l-theanine cause hair loss.

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