We live in an incredibly fast-paced and competitive society. Strenuous hours of mentally demanding work is the reality for most individuals, so it is important to stay active and creative whenever we get the opportunity. The question remains, is it possible to increase our intellectual performance without long-term side effects?
In this supplement guide, we are discussing L-theanine, a natural component generally found in green tea. It is known to promote concentration and minimize stress levels. Some say it is comparable to coffee, but without the jitters. Think it sounds too good to be true? Read on to find out!
- 1 Weekly newsletter with the best personal finance tips
- 2 Key Facts
- 3 Our Selection: The Best L-theanine Supplements
- 4 Shopping Guide: Everything You Should Know about L-theanine
- 5 Buyer's Guide
- 6 Summary
- L-theanine is an amino acid derived from tea.
- It is useful for reducing anxiety as well as promoting better concentration and intellectual performance.
- Before choosing the right L-theanine supplement, it is important to consider a few factors, such as dietary restrictions, the labeling and packaging of the product, the ingredients, and the value for money.
Our Selection: The Best L-theanine Supplements
The following products have been hand-picked from our Supplement Guide team. These particular L-theanine supplements stand out among the rest for their value for money, as well as other factors. With these options, there is something for everyone!
Shopping Guide: Everything You Should Know about L-theanine
L-theanine is a natural substance, derived from the tea plant. It has relaxing but not seating properties, and helps to promote intellectual performance in anxious individuals. L-theanine supplements are very popular for their effectiveness and lack of withdrawal symptoms.
What is L-theanine?
L-theanine is capable of affecting the brain directly. Its structure resembles that of the amino acid glutamine, a precursor to certain molecules in the nervous system (neurotransmitters) (5, 6).Thanks to its effects on brain tissue, L-theanine is able to regulate neuronal functions, having the following affects (7):
- Alpha wave predominance: Brain activity is extremely complex. Neurons communicate with each other through oscillating patterns of electrical energy, or brain waves. L-theanine may induce a relaxation-related neural behavior pattern without sedation, called "alpha waves"(7, 8, 9).
- Increased production of dopamine and serotonin: Dopamine and serotonin are known. neurotransmitters that influence mood. L-theanine helps to stimulate the production of these molecules, therefore improving mood and stimulating attention span and concentration (10, 11).
- Changes in GABA concentration: γ-aminobutyric acid (GABA) is the quintessential inhibitory neurotransmitter, capable of promoting relaxation and preventing excess neuronal activation. It is believed that L-theanine consumption could increase neuronal GABA production, inducing a feeling of calm and relaxation.
- Inhibition of glutamate release: Contrary to GABA, glutamate is an activating neurotransmitter. However, an excessive increase in this molecule can have harmful effects on neurons. L-theanine acts as a glutamate buffer, softening its effects on the nervous system. (12, 13, 14).
- Reduction of oxidative damage: According to several different studies, L-theanine is able to bind to neuron receptors, preventing long-term neuronal damage and degeneration caused by excessive exposure to stressful situations (11, 15, 16).
Given these promising results, it is important to remember that most of the currently available studies will need to go through more trials before they can be fully accepted by the scientific community. One study found that people who drink green tea -- which is high in L-theanine -- had a lower risk of stroke. However it is unknown if it was actually the L-theanine in the green tea that produced the benefit. L- theanine could also boost the benefits -- and reduce side effects -- of some drugs for cancer treatment. But it is unknown yet whether L-theanine supplements would have these benefits in people. More research is needed to know for sure.
Isolated studies have also found possible effects of L-theanine such as (4):
- Lowering blood pressure: Very high doses of L-theanine (1000 mg or higher) appear to be able to lower blood pressure in animal tests.
- Lowering of cholesterol: Some studies in very early stages have found that the consumption of L-theanine could prevent the depositing of cholesterol in the arteries. Atherosclerosis, the main cause of cardiovascular disease, begins with the build up of cholesterol in the wall of the blood vessels.
- Immunity booster: It is suspected that L-theanine could have some antibacterial functions, increasing the activity of cells in the immune system.
- Antioxidant: L-theanine could inhibit the toxic effect of certain drugs on cells, demonstrating a potential antioxidant function.
Is it possible to get the most out of L-theanine simply by drinking tea?
Clinical trials show that the benefits of L-theanine on the nervous system appear after consuming between 50 and 400 mg of this amino acid (18, 19, 20).In the following table, we outline the various amounts of L-theanine present in different types of tea(21):
|Cup of tea (15 grams)||Approximate L-theanine content (mg)|
|Sencha Green Tea.||45|
Depending on the type, brand, and temperature of the water, you would need to consume several cups of tea per day to obtain the benefits described by scientists. Because of this, many people turn to supplements, allowing them to consume the effective doses of this amino acid comfortably and easily.
How do you take L-theanine supplements?
- What dosage? Generally, a dose between 50 and 400mg per day is recommended. Although there is no official maximum limit, it is advised not to exceed the recommended daily dose.
- What time?: L-theanine supplements can be very useful when taken before a mentally demanding task, as they can boost intellectual performance. They can also be taken in the morning or mid-afternoon to improve sleep quality and promote a state of relaxation.
- Can you take it with food? There is really no data available as to the effect of food on L-theanine absorption. However, most manufacturers advise taking the supplements on an empty stomach.
The supplements generally start to take effect between 45 and 60 minutes after taking them, remaining active for approximately 15 hours. The characteristics of this component do not form a tolerance or resistance, therefore most individuals will not need to increase the dose over time. .
Is L-theanine better than caffeine?
When it comes to L-theanine, some experts claim that it has the benefits of caffeine while lacking the side effects. This hypothesis seems to be supported by the appearance of alpha waves (which are responsible for attention and relaxation (16). The following table shows a comparison of the effects of both substances (23, 24, 25, 26, 27, 28, 29, 30):
|Effect||Caffeine||L-theanine||Caffeine + L-theanine|
|Memery||Slight improvement.||Slight improvement.||Improvement.|
If you need fast energy, caffeine is your best option. L-theanine will be most useful when it comes to tasks where you need attention and a clear mind. The combination of caffeine and L-theanine brings the best of both substances, giving you better focus without affecting your sleep patterns or bringing anxiety. These benefits may result from the specific effects that the amino acid has on brain chemicals that play a role in sleep.
A 2018 study found that people reported having greater sleep satisfaction after taking 450–900 mg of L-theanine daily for 8 weeks. The study participants had generalized anxiety disorder and were taking antidepressants.
Generally, L-theanine and caffeine supplements have a 1:2 ratio, always doubling the amount of L-theanine to the caffeine. For example, you can combine a 100mg dose of caffeine with a 200mg dose of L-theanine. Caffeine can be taken as a drink (one cup of black coffee contains about 80mg) or as a supplement.
What precautions should I be aware of when taking L-theanine supplements?
There is a lack of reliable information when it comes to the long-term health effects of this supplement for pregnant and lactating women, people under the age of eighteen or individuals undergoing chemotherapy (31, 32). In these cases, taking L-theanine without medical supervision is strongly discouraged.
There is conflicting data when it comes to the relationship between L-theanine and the presents of seizures (33). Furthermore, people taking antihypertensive drugs may have altered potency while taking the supplement (34). For this reason, people suffering from epilepsy or hypertension are recommended not to consume this substance without supervision.
L-theanine supplements are considered safe to use for healthy people. Gastrointestinal complaints and headaches have been described, which were alleviated after reducing the dosage. This substance could also lower blood pressure in predisposed people, which could cause dizziness.
There are plenty of L-theanine supplements available on the market. But how do you know which is the best one for you? The following purchase criteria will help you make the smartest decision, without needing to spend hours searching online.
L-theanine is derived from the extract of Camellia Sinensis, the tea plant. In its pure form, this supplement is suitable for vegans, celiacs, lactose intolerant individuals, and those allergic to soy. However, the bonding agents used to combine the ingredients could possibly include undesirable products. Always check the labeling before buying if you have certain dietary restrictions.
A good quality supplement brand will include the concentration of L-theanine included in each dose on its label. It should also include a list of ingredients and information about the allergens contained in the product. This data should be clear and perfectly visible and written in plain English.
L-theanine can be sold under alternative names. The term "theanine" is also widely used and refers to the same amino acid. Theanine and L-theanine can be used interchangeably. Another less popular, but equally valid name is gamma glutamylethymide (5-N-ethyl-glutamine).
L-theanine supplements should be sold in perfectly sealed containers that keep the product in the best possible condition. If the item is purchased online, shipping should take into account the necessary precautions, avoiding light, odors, and knocks.
No toxic or dangerous effects have been described due to the consumption of L-theanine after its expiration date. However, taking expired L-theanine supplements may be less potent and may not give the desired effects compared to taking it before its use-by date.
L-theanine is a supplement that is very much appreciated by those who need to perform their best everyday, which is most of us. This completely natural substance derived from tea could revolutionize your day-to-day life, helping you achieve the mindfulness that is needed for studying and for work.
The best kept secret of the tea aficionados is now available to you! L-theanine may affect the levels of certain chemicals in the brain. These include serotonin and dopamine, which influence mood, sleep, and emotion, and cortisol, which helps the body deal with stress. Consumed individually or combined with morning coffee, L-theanine will increase your concentration levels and help to promote productivity.
If you liked our guideline on L-theanine and found it helpful, please leave and comment and share with your friends!
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