Reviewing Sleep Supplement Ingredients: Tryptophan

Reviewing Sleep Supplement Ingredients: Tryptophan

Welcome back to’s supplement ingredient review series for sleep. In this post, we will be taking a closer look at tryptophan, a popular supplement ingredient known for its potential sleep benefits.

What is Tryptophan?

Tryptophan is an essential amino acid that is commonly found in protein-rich foods such as meat, poultry, fish, eggs, and dairy products. It is also available as a dietary supplement in the form of capsules, tablets, or powders.

What Effects Does Tryptophan Have on the Brain/Body?

Tryptophan plays an essential role in the body by helping to produce neurotransmitters such as serotonin and melatonin. Serotonin is a neurotransmitter that regulates mood, appetite, and sleep, while melatonin is a hormone that helps regulate the sleep-wake cycle.

Benefits for Sleep

Tryptophan has been studied for its potential sleep benefits. By increasing serotonin levels, tryptophan may help promote relaxation and reduce anxiety, leading to improved sleep quality. Additionally, tryptophan may increase the production of melatonin, which can help regulate the sleep-wake cycle and improve sleep duration.

Potential Side Effects

While tryptophan is generally considered safe, some people may experience side effects such as nausea, headache, and dizziness. Additionally, tryptophan supplements may interact with certain medications, such as antidepressants and MAO inhibitors, and should not be taken without consulting a healthcare provider.

Why We Didn't Include Tryptophan in Our Knocked Formula

While tryptophan has shown potential sleep benefits, we did not include it in our Knocked formula. This is because we believe that other ingredients, such as Magnesium and L-theanine, have more robust clinical evidence and are more effective for promoting relaxation and improving sleep quality.

Tryptophan is an essential amino acid that may offer potential sleep benefits. However, it is important to consult with a healthcare provider before taking any supplements, as they may interact with certain medications. At, we strive to provide the best possible sleep supplements to our customers and have chosen to exclude tryptophan from our formula in favor of other ingredients that have more robust clinical evidence. Stay tuned for our next supplement ingredient review for sleep!


  1. Richard, D. M., Dawes, M. A., Mathias, C. W., Acheson, A., Hill-Kapturczak, N., & Dougherty, D. M. (2009). L-Tryptophan: Basic Metabolic Functions, Behavioral Research and Therapeutic Indications. International Journal of Tryptophan Research, 2, IJTR.S2129. []

  2. Silber, B. Y., & Schmitt, J. A. (2010). Effects of tryptophan loading on human cognition, mood, and sleep. Neuroscience & Biobehavioral Reviews, 34(3), 387-407. []

  3. Fernstrom, J. D., & Wurtman, R. J. (1971). Brain serotonin content: Physiological dependence on plasma tryptophan levels. Science, 173(3992), 149-152. []

  4. Brzezinski, A., Vangel, M. G., & Wurtman, R. J. (2005). Effects of exogenous melatonin on sleep: a meta-analysis. Sleep Medicine Reviews, 9(1), 41-50. []

  5. Dehkordi, O., Rose, J. E., Fatemi, M., Allameh, A., Balali-Mood, M., & Sameni, H. R. (2018). L-Tryptophan-Induced Increases in Serotonin and Tryptophan in the Blood and Brain of Rats: Effects on Behavior and the 5-HT2A Receptor. Archives of Iranian Medicine, 21(5), 204-213. []

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Learn More About Knocked

Knocked Sleep Support is a natural, non-habit forming, melatonin-free sleep aid that relies on simple, mineral and herb based ingredients to help you fall and stay asleep without feeling groggy the next morning. 

No Melatonin. Just Science.

Science-Backed Ingredients, Safe for Daily Use

Knocked is safe to use every day. We’ve done the research, so you don’t have to. We use natural mineral and herb based ingredients that have high safety margins and are non-habit forming.

Supports Your Circadian Rhythm

Knocked is naturally effective. Our ingredients and behavioral sleep tools are proven to support your body's natural sleep processes by easing your nervous system and promoting a state of relaxation.

No More Groggy Mornings

Knocked is melatonin-free. Studies show long-term melatonin use results in hormone imbalances that make it more difficult for you to achieve natural, high-quality sleep.