Green tea powder, catechins, and theanine also reduced triglyceride levels. The researchers concluded that not only can caffeine help prevent weight gain and fat accumulation, but theanine can, too.
Some research says that L-theanine can help in losing weight. The combined effect of L-theanine and caffeine can reduce triglyceride and non-esterified fatty acids (NEFA) levels and assist in lowering cellular fat accumulation [3].
When taken by mouth: L-theanine is possibly safe when used short-term. Doses of up to 900 mg daily have been safely used for 8 weeks. It isn't clear if L-theanine is safe to use for longer periods of time. It might cause mild side effects, such as headache or sleepiness.
L-THEANINE
It reduces the feeling of hunger and cravings, and it also promotes metabolism.
After being absorbed into the body, L-theanine can penetrate the blood-brain barrier and regulate the secretion of neurotransmitters of central nervous system cells [13] and levels of hormones such as corticosterone (CORT) and adrenaline (EPI) in the serum.
So, should you take L-theanine in the morning or at night? If you're looking to get a good night's sleep, take L-theanine at night. For example, if you need help getting to sleep, you won't want to drink caffeinated tea at night, so you should opt for caffeine-free or herbal tea before bed.
Diarrhea. L-theanine may cause diarrhea in some people. If you experience this side effect, stop taking L-theanine and see your doctor.
After taking advice from experts, the FDA classified L-theanine as “generally recognized as safe.” This classification means that they believe this additive to be safe when people use it as the packaging suggests. However, women who are pregnant or breastfeeding should not use L-theanine.
Caffeine and theanine were shown to suppress body weight increase and fat accumulation. Combining caffeine and L-theanine for weight loss may bring positive results.
About 20 minutes after ingestion, L-theanine naturally lowers the body's cortisol levels. Cortisol is that pesky hormone that shoots up when you're feeling stressed (a not-so-fun fact, it also aids the body in storing fat, too).
L-theanine can help foster a state of calm, attentive wakefulness. L-theanine has positive effects on both the mental and physical symptoms of stress, including lowering heart rate and blood pressure. Research suggests that L-theanine can help reduce anxiety in people with schizophrenia and schizoaffective disorder.
L-theanine inhibits the expression inflammatory factors in the liver tissue. (A) Immunoblot showing expression levels of iNOS, IL-1β and IL-6 in the indicated groups.
L-theanine has been historically reported as a relaxing agent, prompting scientific research on its pharmacology. Animal neurochemistry studies suggest that L-theanine increases brain serotonin, dopamine, GABA levels and has micromolar affinities for AMPA, Kainate and NMDA receptors.
To the best of our knowledge, tea is the only main dietary source of L-theanine.
The amino acid L-theanine is an effective treatment of moderate and severe anxiety and does not cause drowsiness.
L-theanine Dosage and Use
L-theanine is one of my most common treatments for anxiousness and may help any of the three sub-types. It's usually taken in doses from 50-100 mg once or twice daily. In more severe cases, it may be taken 3 or 4 times per day. It is not habit forming like many anti-anxiety medications.
Many holistic health care professionals suggest starting with a daily dose of 100 milligrams of l-theanine, increasing to a maximum of 400mg per day, for the treatment of stress or anxiety. Effects are usually noticeable within 30 minutes, and can last as long as eight to ten hours.
To optimize uptake from the intestine and across the blood brain barrier, L-theanine may be best taken on an empty stomach, and especially away from protein foods and amino acid-containing supplements.
With that in mind, L-theanine seems to be particularly beneficial for combatting stress-related sleep issues. Melatonin, on the other hand, just flat out encourages sleep. This is what makes melatonin a generally more effective sleep supporter than L-theanine, or any other natural sleep aid.
Magnesium is one of the most effective (and natural) supplements you can take for sleep. You can read our full guide to magnesium and sleep here, but it promotes deep sleep and full body recovery. When you combine l-theanine and magnesium - you get the best of both worlds.
Possible Drawbacks of L-Theanine for Anxiety
Can Decrease Serotonin Levels While L-theanine also has the potential to increase serotonin levels in the brain, it has occasionally been shown to decrease them as well.
Adding in cardio, such as a brisk walk will help lower your cortisol levels and control your stress. Once you have your stress under control, you can add interval training and sprints two or three times a week to reduce your belly fat.