One of the most important factors in leading a healthy life is our diet. A balanced diet allows us to live a healthier life and perform the functions our body needs. However, having a balanced diet in our everyday lives can be challenging due to our busy schedules. One of the key nutrients most people lack in our diet is amino acids.
Amino acids build protein which is necessary for our body to function properly. Oftentimes, we can get amino acids from food sources like meat, eggs, fish, legumes, nuts, and whole grains.
In this article, we will focus on two amino acids that play a major role in our overall health— DLPA (DL-Phenylalanine) and Tyrosine.
We will examine these two amino acids and their health benefits, side effects, and dosages. Lastly, we will cover the key question often asked when talking about these two nutrients: whether one can take DLPA and Tyrosine together.
DLPA vs. Tyrosine: What are They?
DL-Phenylalanine or DLPA is a nutritional supplement that consists of two forms of Phenylalanine in equal parts, which are D- and L-phenylalanine. Moreover, DL-Phenylalanine contains appetite-suppressing, antidepressant, and pain-relieving properties .
L-phenylalanine is what our body produces that helps in building proteins, neurotransmitters, and key molecules. It is an essential amino acid, meaning the body needs to obtain it from food sources like meat, soy, eggs, nuts, and dairy .
D-phenylalanine is the artificial form that is produced in the lab. Due to its nature, our bodies cannot use it to build proteins, but it has anti-depressant and pain-relieving properties [3 4].
Meanwhile, Tyrosine is another amino acid that is naturally produced in the body with the help of another amino acid phenylalanine. It was thought to be initially discovered in cheese, hence naming it “tyros” which means cheese in Greek . Unlike the active form– L-phenylalanine, Tyrosine is a non-essential amino acid which means that the body can naturally produce it without supplementing it from our diet.
DLPA vs. Tyrosine: What are their Benefits?
L-phenylalanine builds neurotransmitters like noradrenaline and dopamine, which can help regulate mood, mental health, heart rate, and other critical functions [6 7].
In a clinical trial with 155 patients, supplementing L-phenylalanine of 250mg every day and standard treatment increases its efficacy in 80-90% of the cases . Meanwhile, DLPA with 75-200mg/day dosage relieved the depression symptoms of 12 out of 20 patients taken for 20 days. Furthermore, it provided mild to moderate relief in four patients and failed to affect the remaining four .
Due to Tyrosine’s antidepressant properties, which help increase neurotransmitter production, it is also said to relieve symptoms of depression in patients . However, early research does not support its claim.
In a study conducted on 65 people with depression, the result showed that Tyrosine does not have anti-depressant effects . This is after patients received either 100mg/kg of tyrosine, 2.5mg/kg of antidepressant medicine, or a placebo for the next 4 weeks.
Side Effects of DLPA vs. Tyrosine
There are no reported critical DLPA side effects in clinical trials conducted [11 12 13]. Furthermore, a separate study on two forms of DLPA showed that D- and L-phenylalanine supplements are well-tolerated and generally safe [14 15].
The US FDA considered Tyrosine as “generally recognized as safe” (GRAS) . Conversely, a dose of 68mg per pound or 150mg per kg of body weight per day has been supplemented and was found safe based on the study [17 18].
Here are the following dosages of DLPA that provided beneficial effects to the users according to the clinical trials:
- For patients with depression: 50 – 200 mg for 4 weeks
- Chronic pain: 1500 – 3000 mg daily
- For patients with attention deficit disorder: increasing between 150 and 1200 mg per day for 2 weeks
Meanwhile, Tyrosine’s best dosage is between 45 and 68 mg per pound or 100 – 150 mg kg of body weight.
DLPA vs. Tyrosine: Can you take them together?
There are still no reported studies that both DLPA and Tyrosine can be taken together. Although both of these amino acids can be taken individually, exercising caution is still important due to the lack of scientific claims for their efficacy when taken together.
Like every food and supplement our body take, various reactions may arise in each person. Therefore, this is essential to consider when incorporating any of these two or both supplements into your health routine. Always consult with health professionals who can properly guide you with the right dosage and information about DLPA and Tyrosine.
Bottomline: DLPA vs. Tyrosine
DLPA supplements are two equal parts of D- and L-phenylalanine, which provide building blocks for neurotransmitters and proteins. Studies are showing its anti-depressant effect on patients with milder forms of depression. Moreover, DLPA is considered safe and well-tolerated.
Meanwhile, Tyrosine is another amino acid produced by the body with the help of another amino acid called phenylalanine. Some studies suggested that it can also relieve depression symptoms, but more research is still needed to back up the claim. The US FDA deemed Tyrosine as safe and well-tolerated.
Lastly, there is still no evidence that can prove whether DLPA and Tyrosine can be taken together. Although both of these amino acids have critical functions in the body, it is safe to use them separately until valid studies prove that they can be taken together.
Disclaimer: This article is only a guide. It does not substitute the advice given by your healthcare professional. Before making any health-related decision, consult your healthcare professional.
Editorial References And Fact-Checking
- National Center for Biotechnology Information (2022). PubChem Compound Summary for CID 994, DL-Phenylalanine. Retrieved December 13, 2022 from https://pubchem.ncbi.nlm.nih.gov/compound/DL-Phenylalanine.
- Fernstrom JD, Fernstrom MH. Tyrosine, phenylalanine, and catecholamine synthesis and function in the brain. J Nutr. 2007 Jun;137(6 Suppl 1):1539S-1547S; discussion 1548S. doi: 10.1093/jn/137.6.1539S. PMID: 17513421.
- Lehmann WD, Theobald N, Fischer R, Heinrich HC. Stereospecificity of phenylalanine plasma kinetics and hydroxylation in man following oral application of a stable isotope-labelled pseudo-racemic mixture of L- and D-phenylalanine. Clin Chim Acta. 1983 Mar 14;128(2-3):181-98. doi: 10.1016/0009-8981(83)90319-4. PMID: 6851137.
- National Center for Biotechnology Information (2022). PubChem Compound Summary for CID 71567, D-phenylalanine. Retrieved December 13, 2022 from https://pubchem.ncbi.nlm.nih.gov/compound/D-phenylalanine.
- Sathyanarayana Rao, T. S., & Yeragani, V. K. (2009). Hypertensive crisis and cheese. Indian Journal of Psychiatry, 51(1), 65-66. https://doi.org/10.4103/0019-5545.44910
- Roberts, S. A. (1998a, December 1). Phenylalanine and Tyrosine Metabolism in Neonates Receiving Parenteral Nutrition Differing in Pattern of Amino Acids. Nature. https://www.nature.com/articles/pr1998581z?error=cookies_not_supported&code=39e550d0-ac8d-4806-8e43-04e469202bd5
- Lou HC. Dopamine precursors and brain function in phenylalanine hydroxylase deficiency. Acta Paediatr Suppl. 1994 Dec;407:86-8. doi: 10.1111/j.1651-2227.1994.tb13461.x. PMID: 7766968.
- Birkmayer W, Riederer P, Linauer W, Knoll J. L-deprenyl plus L-phenylalanine in the treatment of depression. J Neural Transm. 1984;59(1):81-7. doi: 10.1007/BF01249880. PMID: 6425455.
- Beckmann H, Strauss MA, Ludolph E. Dl-phenylalanine in depressed patients: an open study. J Neural Transm. 1977;41(2-3):123-34. doi: 10.1007/BF01670277. PMID: 335027.
- Parker G, Brotchie H. Mood effects of the amino acids tryptophan and tyrosine: ‘Food for Thought’ III. Acta Psychiatr Scand. 2011 Dec;124(6):417-26. doi: 10.1111/j.1600-0447.2011.01706.x. Epub 2011 Apr 12. PMID: 21488845.
- Gelenberg AJ, Wojcik JD, Falk WE, Baldessarini RJ, Zeisel SH, Schoenfeld D, Mok GS. Tyrosine for depression: a double-blind trial. J Affect Disord. 1990 Jun;19(2):125-32. doi: 10.1016/0165-0327(90)90017-3. PMID: 2142699.
- Fischer E, Heller B, Nachon M, Spatz H. Therapy of depression by phenylalanine. Preliminary note. Arzneimittelforschung. 1975 Jan;25(1):132. PMID: 1173765.
- Beckmann H, Athen D, Olteanu M, Zimmer R. DL-phenylalanine versus imipramine: a double-blind controlled study. Arch Psychiatr Nervenkr (1970). 1979 Jul 4;227(1):49-58. doi: 10.1007/BF00585677. PMID: 387000.
- Wood DR, Reimherr FW, Wender PH. Treatment of attention deficit disorder with DL-phenylalanine. Psychiatry Res. 1985 Sep;16(1):21-6. doi: 10.1016/0165-1781(85)90024-1. PMID: 3903813.
- Camacho F, Mazuecos J. Oral and topical L-phenylalanine, clobetasol propionate, and UVA/sunlight–a new study for the treatment of vitiligo. J Drugs Dermatol. 2002 Sep;1(2):127-31. PMID: 12847735.
- Zametkin AJ, Karoum F, Rapoport JL. Treatment of hyperactive children with D-phenylalanine. Am J Psychiatry. 1987 Jun;144(6):792-4. doi: 10.1176/ajp.144.6.792. PMID: 3296793.
- CFR – Code of Federal Regulations Title 21. (n.d.). https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=172.320
- Wood DR, Reimherr FW, Wender PH. Amino acid precursors for the treatment of attention deficit disorder, residual type. Psychopharmacol Bull. 1985;21(1):146-9. PMID: 3885291.
- Reimherr FW, Wender PH, Wood DR, Ward M. An open trial of L-tyrosine in the treatment of attention deficit disorder, residual type. Am J Psychiatry. 1987 Aug;144(8):1071-3. doi: 10.1176/ajp.144.8.1071. PMID: 3300376.