From MEpedia, a crowd-sourced encyclopedia of ME and CFS science and history

Phenylalanine, often sold as L-phenylalanine or DL-phenylalanine, is an essential amino acid that is normally converted to tyrosine.[1][2][3]

Theory[edit | edit source]

McGregor (2019) found that in people with ME/CFS, the 7-day severity of post-exertional malaise (PEM) and the 12-month frequency of PEM scores correlated with blood glucose levels, and negatively correlated with hypoxanthine, phenylalanine, lactate and threonine.[4]

Evidence[edit | edit source]

Risks and safety[edit | edit source]

Phenylalanine is generally recognized as safe, except for people with phenylketonuria (PKU), a genetic disorder that prevents the metabolism of phenylalanine.[3] Phenylalanine is found in many different foods.

Costs and availability[edit | edit source]

Inexpensive and available over the counter as a nutritional supplement.

Notable studies[edit | edit source]

  • 2016, Metabolic profiling indicates impaired pyruvate dehydrogenase function in myalgic encephalopathy/chronic fatigue syndrome[5] (Full Text)
  • 1977, DL-phenylalanine in depressed patients: An open study[6] (Abstract)
  • 2019, Post-exertional malaise is associated with hypermetabolism, hypoacetylation and purine metabolism deregulation in ME/CFS cases[4] - (Full text)

See also[edit | edit source]

Learn more[edit | edit source]

References[edit | edit source]

  1. "Definition of PHENYLALANINE". Merrian-Webster Dictionary. Retrieved March 7, 2021.
  2. "Phenylalanine". Retrieved March 7, 2021.
  3. 3.0 3.1 PubChem. "DL-Phenylalanine". Retrieved March 7, 2021.
  4. 4.0 4.1 McGregor, Neil R.; Armstrong, Christopher W.; Lewis, Donald P.; Gooley, Paul R. (September 2019). "Post-Exertional Malaise Is Associated with Hypermetabolism, Hypoacetylation and Purine Metabolism Deregulation in ME/CFS Cases". Diagnostics. 9 (3): 70. doi:10.3390/diagnostics9030070.
  5. Fluge, Øystein; Mella, Olav; Bruland, Ove; Risa, Kristin; Dyrstad, Sissel E.; Alme, Kine; Rekeland, Ingrid G.; Sapkota, Dipak; Røsland, Gro V.; Fosså, Alexander; Ktoridou-Valen, Irini; Lunde, Sigrid; Sørland, Kari; Lien, Katarina; Herder, Ingrid; Thürmer, Hanne; Gotaas, Merete E.; Baranowska, Katarzyna A.; Bohnen, Louis M.L.J.; Schäfer, Christoph; McCann, Adrian; Sommerfelt, Kristian; Helgeland, Lars; Ueland, Per M.; Dahl, Olav; Tronstad, Karl J. (2016). "Metabolic profiling indicates impaired pyruvate dehydrogenase function in myalgic encephalopathy/chronic fatigue syndrome". JCI Insight. 1 (21): e89376. doi:10.1172/jci.insight.89376.
  6. Beckmann, H.; Strauss, M.A.; Ludolph, E. (June 1, 1977). "Dl-phenylalanine in depressed patients: An open study". Journal of Neural Transmission. 41 (2): 123–134. doi:10.1007/BF01670277. ISSN 1435-1463.