GLISIN, ASAM AMINO
10 ALASAN UNTUK MELENGKAPI DENGAN GLISIN
Terakhir Diperbarui pada 20 November 2023 oleh Keir WatsonFoto latar belakang dibuat oleh kjpargeter – www.freepik.com
Glisin adalah salah satu asam amino paling sederhana namun memiliki beberapa fungsi luar biasa dan tak terduga dalam tubuh. Glisin ditemukan di sebagian besar makanan berbasis protein, dan juga disintesis di dalam tubuh, namun, semakin banyak bukti yang menunjukkan bahwa hampir semua orang akan mendapat manfaat dari suplementasi dengan nutrisi yang mudah didapat dan murah ini.
Perkenalan
◀ STRUKTUR GLISIN
Semua asam amino memiliki struktur molekul dasar yang sama, hanya berbeda pada pola atom yang terdapat pada rantai sampingnya (R). Glisin adalah asam amino paling sederhana, hanya memiliki satu atom hidrogen pada posisi ini.
Sebagai bahan penyusun glisin diperlukan untuk sintesis berbagai protein penting, termasuk serin, sarkosin, purin, kreatin, hemoglobin, glutathione, dan kolagen — protein paling melimpah di tubuh manusia [ Adeva-Andany, 2018 ], TAPI itu memiliki lusinan fungsi dan sifat lain, yang bekerja di banyak sistem biokimia dan beroperasi di berbagai tingkatan, seringkali secara sinergis.
Dalam artikel ini kita akan melihat semakin banyak bukti yang mendukung pemberian suplemen 10g glisin per hari. Berikut adalah sepuluh alasan secara singkat (mengklik salah satu judul akan membawa Anda ke bagian tersebut di artikel utama)…
TL;DR
- Setiap orang kekurangan glisin karena hambatan evolusi yang membatasi jumlah yang dapat kita sintesis
- Melengkapi glisin sebanyak 10g per hari meningkatkan sintesis kolagen sebesar 200%
- Glisin memiliki berbagai efek anti-inflamasi
- Glisin memiliki efek menstabilkan pada sistem saraf pusat dan meningkatkan kualitas tidur
- Glycine memiliki serangkaian efek anti-obesitas dan anti-diabetes
- Glisin melindungi sel dari kerusakan akibat cedera, trauma, hipoksia , kedinginan, dll
- Glisin melindungi lambung dan usus, mengurangi peradangan dan ulserasi
- Glisin meningkatkan kapasitas antioksidan tubuh dan meningkatkan detoksifikasi melalui berbagai jalur
- Glisin memiliki berbagai manfaat untuk sistem kardiovaskular, meningkatkan pembekuan darah, fungsi jantung, dan meningkatkan lipid darah
- Glisin memiliki sifat umur panjang, anti-glikasi dan anti-kanker
Glisin Tambahan
Dalam bentuk tambahan, glisin adalah padatan kristal putih, yang secara mengejutkan terlihat seperti gula dan mudah larut dalam air hangat. Memang benar bahwa glisin adalah salah satu asam amino termanis, ⅓ semanis gula meja.
Salah satu cara termudah untuk meningkatkan asupan glisin harian Anda adalah dengan menggunakannya sebagai pengganti gula pada makanan penutup dan minuman panas. Berbeda dengan gula, glisin tidak menyebabkan kerusakan gigi. Diminum bersama makanan sebenarnya mengurangi kenaikan gula darah dibandingkan dengan makanan yang sama tanpa glisin. Trik terakhir sebagai pengganti gula adalah mengurangi rasa lapar melalui stimulasi hormon usus. Glisin juga dapat ditambahkan ke sup dan saus jika rasa manisnya yang ringan melengkapi rasa gurih.
Itu adalah dasar yang rendah. Jika Anda menginginkan detailnya, dan menurut saya Anda menginginkannya, baca terus!
PASAL UTAMA
10 Alasan untuk melengkapi dengan Glycine
Setiap orang kekurangan glisin
Karena tubuh dapat mensintesis glisin dari protein lain, maka glisin awalnya digolongkan sebagai nutrisi non-esensial. Namun, ternyata karena hambatan evolusi, semua ikan, burung, dan mamalia (termasuk manusia), tidak mampu memproduksi glisin dalam jumlah yang cukup untuk sintesis kolagen yang optimal. [ Alves, 2019 ]
Keterbatasan evolusi ini menjelaskan mengapa osteoartritis merupakan salah satu dari sedikit penyakit kronis yang telah diamati pada hewan liar, termasuk gajah, badak, dan primata, serta terbukti dalam catatan fosil manusia yang sehat. Tanpa kolagen yang cukup untuk menggantikan tulang rawan yang menua, osteoartritis dapat terjadi.
Meskipun tubuh dapat mensintesis glisin, sejumlah proses metabolisme kompetitif membatasi jumlah yang dapat diproduksi. Sebagian besar glisin yang disintesis dalam tubuh manusia berasal dari serin, dengan perhitungan teoritis menunjukkan bahwa manusia hanya dapat mensintesis sekitar 2,5 g glisin setiap hari.
Sisa glisin dalam tubuh berasal dari makanan, terutama ditemukan pada makanan berprotein tinggi seperti ikan, daging, telur, dan kacang-kacangan. Oleh karena itu, asupan makanan bervariasi dari sekitar 1,5 hingga 3 g/hari, tergantung pada jumlah protein dalam makanan. Asupan glisin di kalangan vegetarian dan vegan biasanya jauh lebih rendah dibandingkan dengan omnivora, meskipun kadar glisin dalam darah mereka seringkali sama. Paradoks ini dapat dijelaskan oleh fakta bahwa daging juga mengandung asam amino metionin yang tinggi, dan metionin 'menggunakan' glisin selama metabolismenya. [ Alves, 2019 ]
Studi tentang proses metabolisme yang bergantung pada glisin telah menunjukkan bahwa banyak proses yang dibatasi oleh ketersediaan glisin, seringkali bergantung pada dosis; dan dalam banyak kasus, hal ini berjalan jauh di bawah efisiensi maksimumnya. Pengamatan seperti ini menambah bobot hipotesis bahwa manusia kekurangan glisin secara kronis. Kekurangan ini tidak cukup mempengaruhi kesehatan sebelum reproduksi sehingga hanya mengalami sedikit tekanan selektif sepanjang waktu evolusi. Sebaliknya, kekurangan glisin tampaknya muncul terutama di kemudian hari melalui proses yang berhubungan dengan penuaan. Akibatnya, banyak peneliti telah mengklasifikasikan ulang glisin sebagai esensial bersyarat , atau esensial . Bukti lebih lanjut telah datang dari berbagai penelitian yang menunjukkan manfaat kesehatan dari suplementasi dengan dosis antara 5g dan 40g per hari.
Seberapa besar defisit glisin?
Sebuah studi rinci tentang kebutuhan glisin tubuh dibandingkan dengan jumlah yang tersedia dari sintesis glisin dan makanan menunjukkan bahwa tubuh orang dewasa mengalami defisit sekitar 10g per hari. [ Meléndez-Hevia dkk, 2009 ]
…glisin harus dianggap sebagai asam amino esensial karena kapasitas sintesisnya jauh lebih rendah daripada kebutuhan sebenarnya. Kami juga menunjukkan bahwa kekurangan ini tidak dapat diatasi dengan pola makan teratur sehingga glisin harus ditambahkan ke dalamnya sebagai suplemen nutrisi dalam jumlah tinggi, sekitar 10 g/hari.
Paz-Lugo dkk, 2018
Manfaat suplementasi glisin
Defisit ini berarti bahwa di banyak jalur kesehatan yang bergantung pada glisin meningkat secara signifikan ketika glisin ditambahkan. Daftar singkat manfaat tersebut meliputi:
- Mencegah cedera jaringan
- Meningkatkan kapasitas anti-oksidatif
- Mempromosikan sintesis protein dan penyembuhan luka
- Meningkatkan kekebalan; Dan
- Mengobati gangguan metabolisme seperti obesitas dan diabetes, penyakit kardiovaskular, cedera iskemia-reperfusi, kanker, dan berbagai penyakit inflamasi.
Berbagai efek menguntungkan dari glisin, ditambah dengan sintesis de novo yang tidak mencukupi, mendukung gagasan bahwa glisin merupakan asam amino esensial dan juga fungsional untuk mamalia (termasuk manusia).
Wang dkk, 2013
Sintesis Glisin dan Kolagen
Kolagen membentuk sepertiga dari protein dalam tubuh. Setiap asam amino ketiga dalam kolagen adalah glisin menjadikannya asam amino paling melimpah dalam kolagen [ Li & Wu, 2017 ].
Dua asam amino penting lainnya untuk sintesis kolagen adalah prolin dan lisin – yang terakhir diperlukan untuk perancah. Penelitian menunjukkan bahwa meskipun kadar lisin dan prolin dalam darah normal optimal untuk sintesis kolagen, kadar glisin jauh di bawah konsentrasi optimalnya. Oleh karena itu, suplementasi 10g glisin per hari diharapkan dapat meningkatkan sintesis kolagen sebesar 200%. [ Paz Lugo dkk, 2018 ]
Osteoartritis
Seiring bertambahnya usia, kolagen dalam tubuh kita akan rusak dan sulit digantikan. Hal ini sangat penting pada kondisi seperti osteoartritis (yang menyerang 40% orang berusia di atas 65 tahun) di mana regenerasi tulang rawan yang rusak memerlukan sintesis kolagen yang cukup besar. Penelitian terbaru menunjukkan bahwa sintesis tersebut terutama dibatasi oleh ketersediaan glisin, dan tingkat normal glisin dari makanan tidak cukup untuk menggantikan kolagen. Oleh karena itu, glisin tambahan diperlukan untuk membangun kembali kolagen.
[ Paz-Lugo dkk, 2018 ]
Tendon Achilles
Tendon terutama terdiri dari kolagen tetapi karena suplai darah yang buruk, penyembuhannya lambat setelah cedera atau peradangan. Sebuah penelitian pada hewan menemukan bahwa glisin mampu mengurangi peradangan dan meningkatkan remodeling tulang rawan pada tendon Achilles. “Diet glisin merangsang sintesis hidroksiprolin, glikosaminoglikan, protein non-kolagen dan tampaknya mempertahankan atau meningkatkan pengorganisasian molekul kolagen. Hasil biomekanik menunjukkan bahwa tendon lebih tahan terhadap beban mekanis setelah pengobatan dengan diet glisin. Glisin juga menginduksi remodeling jaringan secara cepat bila dibandingkan dengan kelompok tanpa pengobatan.”
Data dari penelitian ini menunjukkan bahwa suplementasi glisin dari makanan mungkin merupakan terapi tambahan yang berguna untuk individu dengan cedera inflamasi pada tendon, seperti cedera tendon Achilles, dan mungkin jenis cedera jaringan ikat dan kejadian inflamasi lainnya.
Pedrozo Vieira dkk, 2014
Sebuah penelitian yang lebih baru menunjukkan bahwa tenosit (sel utama dalam tendon, yang bertanggung jawab untuk perbaikan jaringan) merespons dengan baik terhadap glisin, sehingga meningkatkan proses remodeling. [ Vieera dkk, 2018 ]
Suplemen Glisin vs Kolagen / Gelatin
Beberapa tanda penuaan yang paling terlihat disebabkan oleh keterbatasan remodeling kolagen seiring bertambahnya usia. Sejak usia 25 tahun, kerusakan kolagen melebihi penggantian kolagen, menyebabkan kerutan, kulit kendur dan warna kulit berkurang, serta peningkatan risiko osteoartritis dan masalah sendi lainnya. Yang kurang terlihat adalah peningkatan risiko osteoporosis karena hilangnya kolagen mempengaruhi kekuatan tulang. Sedikit informasi langsung yang tersedia mengenai bagaimana suplementasi glisin dapat mempengaruhi proses ini, namun penelitian menggunakan kolagen atau gelatin mungkin dapat memberikan informasi.
Melengkapi dengan 10g glisin per hari
akan meningkatkan produksi kolagen sebesar 200%
Saat ini, sebagian besar penelitian anti-penuaan berkisar pada aplikasi internal dan eksternal peptida kolagen dan/atau hidrosolat gelatin. Kedua bahan ini, berasal dari jaringan ikat yang kaya kolagen, mengandung glisin dalam jumlah besar. Meskipun suplemen ini diharapkan menyediakan semua bahan yang diperlukan untuk membentuk kolagen baru, terdapat bukti bahwa (a) hanya sebagian kecil asam amino yang berhasil diperoleh dari produk ini; (b) manusia umumnya kaya akan asam amino prolin dan lisin yang dibutuhkan, namun kekurangan glisin, dan (c) jumlah glisin yang tersedia dari kolagen atau gelatin terhidrolisis kemungkinan terlalu kecil untuk memenuhi kebutuhan sintesis kolagen. [ de Paz-Lugo et al, 2018 ] Jadi, mungkin saja banyak hasil positif yang terlihat dalam penelitian kolagen/gelatin sebagian besar disebabkan oleh kandungan glisin dalam produk ini, dan suplementasi dengan 10g glisin per hari akan memberikan manfaat yang lebih besar bagi tubuh. mencapai banyak manfaat yang dilaporkan dari kolagen atau gelatin, tetapi lebih efektif dan lebih murah.
Sebagai contoh, dalam studi percontohan percobaan pada manusia baru-baru ini, para peneliti menggunakan peptida kolagen yang mereka tekankan “tinggi glisin” dan mampu menunjukkan perbaikan gejala dan vaskularisasi tendon pada pasien dengan tendinopati Achilles kronis yang dikombinasikan dengan olahraga terstruktur. [ Praet dkk, 2019 ]
Meningkatkan glisin dalam makanan mungkin merupakan strategi untuk membantu regenerasi tulang rawan dengan meningkatkan sintesis kolagen, yang dapat berkontribusi pada pengobatan dan pencegahan osteoartritis.
Efek anti-inflamasi dari Glycine
Glisin mengurangi aktivasi sel inflamasi, termasuk makrofag dan neutrofil.
Fibrosis kistik
Uji coba percontohan secara acak mengenai suplementasi glisin pada pasien muda Fibrosis Kistik menunjukkan perbaikan gejala (dahak), beberapa penanda inflamasi, dan kapasitas pernapasan hanya dalam 8 minggu, dibandingkan dengan kontrol. Pasien Cystic Fibrosis kehilangan sekitar 2% kapasitas Volume Ekspirasi Paksa setiap tahunnya. Dalam penelitian ini kelompok glisin meningkatkan FEV1 mereka sebesar 10% hanya dalam 8 minggu. Para peneliti mencatat bahwa glisin 'dapat ditoleransi dengan baik', dan tidak menunjukkan efek samping negatif apa pun: sangat kontras dengan obat-obatan biasa yang digunakan untuk mengendalikan kondisi ini. [ Vargas dkk, 2017 ]
Gusi dan Mulut
Terdapat beberapa bukti bahwa glisin mungkin efektif dalam mengatasi radang gusi [ Schaumann dkk, 2013 ; Lu dkk, 2018 ] Semburan air yang mengandung glisin saat ini sedang diselidiki untuk digunakan selama perawatan gigi. Uji coba glisin pada hewan pengerat pada mucositis – peradangan mulut yang menyakitkan yang dialami oleh pasien kanker akibat efek samping toksik dari kemoterapi – menunjukkan penyembuhan yang nyata pada mukosa mulut.
Perlu diperhatikan bahwa suplementasi glisin mudah dilakukan, berbiaya rendah, dan tidak memerlukan metode pengobatan invasif.
Sá dkk, 2018
Efek neurologis glisin
Glisin ditemukan di sumsum tulang belakang dan batang otak di mana ia bertindak sebagai neurotransmitter penghambat melalui sistem reseptornya sendiri. Reseptor glisin ada di mana-mana di seluruh sistem saraf dan memainkan peran penting selama perkembangan otak. [ Ito, 2016 ] Glisin juga berinteraksi dengan sistem neurotransmisi glutaminergik melalui reseptor NMDA, yang memerlukan glisin dan glutamat, sekali lagi, terutama memberikan efek penghambatan.
Meningkatkan kualitas tidur
Pernahkah Anda bertanya-tanya mengapa Anda tidak mewujudkan impian Anda secara fisik saat Anda tidur? Anda harus berterima kasih pada glisin untuk itu! 30 tahun yang lalu ditemukan bahwa glisin memediasi penekanan pergerakan otot selama tidur REM. [ Soja, 2008 ]
Suplementasi glisin telah terbukti meningkatkan dan memperdalam tidur tanpa mengubah jam sirkadian atau mengganggu hormon utama tidur-bangun. Penurunan suhu inti dan penurunan tidur REM tampak signifikan.
Menelan glisin sebelum tidur telah terbukti meningkatkan kualitas tidur subjektif dan objektif pada orang yang sulit tidur. Selain itu, subjek yang kurang tidur sebagian yang diberi glisin sebelum tidur mengalami peningkatan kinerja di siang hari dibandingkan mereka yang tidak menerima glisin. [ Bannai, 2012 ]
Belum ada laporan glisin menyebabkan kantuk bila dikonsumsi siang hari.
OCD
Ada satu studi kasus pada seorang anak berusia 17 tahun yang menderita Obsessive Compulsive Disorder (OCD) yang tidak dapat dikendalikan oleh obat-obatan konvensional. Pada usia 22 tahun dia diberi glisin dosis tinggi dan tetap menggunakannya selama 5 tahun. Selama masa ini, terjadi penurunan gejala yang signifikan, kecuali pada periode ketika pengobatan telah berakhir. [ Louis Cleveland dkk, 2010 ]
Skizofrenia
Peran glisin dalam gangguan neurologis merupakan bidang studi yang relatif baru. Dalam beberapa tahun terakhir telah ditemukan bahwa pasien psikosis episode pertama menunjukkan konsentrasi glisin dan glutamat yang tidak normal di otak [ Kim et al, 2018 ], dan pada Gangguan Penggunaan Alkohol, kadar glisin otak berkorelasi terbalik dengan angka tersebut. hari-hari minum berat.
Beberapa penelitian yang melibatkan pasien skizofrenia menemukan pengurangan gejala dengan menggunakan suplementasi glisin dosis tinggi (sekitar 48g/hari), dengan rata-rata pengurangan gejala negatif sebesar 23%. Tindakan tersebut tampaknya melalui peran glisin sebagai koagonis reseptor NMDA. [ Heresco-Levy dkk, 1999 & 2004 , Strzelecki & Rabe-Jabłońska, 2011 ,]
Pemulihan stroke
Stroke iskemik merusak otak melalui eksitasi neurologis (eksitotoksisitas) reseptor NMDA glutamat dan stres oksidatif. Sifat neuroprotektif dan antioksidan Glycine menjadikannya pengobatan yang berharga segera setelah stroke.
Beberapa percobaan di Rusia menetapkan bahwa pemberian 1-2g glisin per hari, di bawah lidah, dimulai dalam waktu 6 jam setelah timbulnya stroke selama 5 hari, mengurangi stres oksidatif, menstabilkan neurotransmiter dan mengurangi angka kematian dalam 30 hari berikutnya. [ Gusev dkk, 1999 , 2000 ];
Sebuah penelitian yang lebih baru menunjukkan bahwa glisin juga dapat melindungi neuron dari kematian setelah stroke hemoragik. [ Zhao dkk. 2018 ]
Efek metabolik dan anti-obesitas Glycine
Glisin telah terbukti bekerja pada berbagai jalur yang terlibat dalam pengembangan sindrom metabolik yang menunjukkan kemungkinan penggunaannya dalam mencegah dan mengobati gangguan metabolisme seperti obesitas dan diabetes.
Kadar glisin darah secara rutin ditemukan menurun pada pasien obesitas dan diabetes. Menambahkan glisin ke dalam makanan telah terbukti memberikan berbagai efek anti-diabetes serta merangsang sekresi insulin. Ada beberapa bukti bahwa ia juga berikatan langsung dengan glukosa, mengurangi jumlah glukosa bebas dalam darah. [ Chilukuri, Februari 2018 ]
Glisin bekerja melalui berbagai jalur yang bermanfaat bagi penyakit metabolik
Glisin bertindak menghambat stres oksidatif (merah), produksi glukosa hati dan asupan makanan. Ini juga secara positif mempengaruhi respons hormonal dan kekebalan (hijau), meningkatkan metilasi (MTHFR), meningkatkan detoksifikasi dan mendukung fungsi mitokondria.
[ Alves at al, Nutrisi, Metabolisme Glisin 2019 dan Perubahannya pada Obesitas dan Penyakit Metabolik ]
Pada tikus yang mengalami obesitas, suplementasi glisin dalam makanan telah terbukti meningkatkan toleransi glukosa dan meningkatkan trigliserida, mencegah penambahan berat badan, penumpukan lemak hati, dan peradangan terkait. Efek serupa terlihat pada tikus yang diberi diet tinggi lemak dan sukrosa dimana suplementasi glisin melindungi mereka dari kerusakan hati.
Glisin memiliki kemampuan untuk menurunkan glukosa darah, menormalkan metabolisme lipid dan mengurangi peradangan.
Sebuah percobaan yang melibatkan 60 orang dewasa dengan sindrom metabolik menemukan bahwa dosis glisin 15 g/hari menyebabkan penurunan penanda stres oksidatif, bersamaan dengan penurunan tekanan darah sistolik yang signifikan. [ Diaz-Flores, 2013 ] Melengkapi pada tingkat ini dapat dengan mudah menyebabkan peningkatan tujuh kali lipat dalam kadar glisin darah yang bersirkulasi. [ McCarty & DiNicolantonio, 2019 ]
Menarik untuk berspekulasi manfaat apa yang mungkin terlihat jika semua produsen minuman bersoda mengganti gula dengan glisin.
Hati Berlemak (NAFLD)
Glisin telah terbukti melindungi hati dari penyakit hati berlemak non-alkohol (NAFLD). Dalam sebuah penelitian pada tikus, mereka yang diberi glisin mengalami penurunan dampak buruk dari diet tinggi gula dengan penanda hati yang lebih baik, stres oksidatif yang lebih rendah, dan akumulasi lemak hati yang lebih sedikit dibandingkan mereka yang tidak diberi glisin. [ Alves dkk, 2019 ]
Efek anti-diabetes
Melengkapi dengan 5 g glisin per hari telah terbukti meningkatkan respon insulin dan toleransi glukosa. Dalam sebuah penelitian terhadap subjek sehat, ketika dikonsumsi bersama makanan, glisin mengurangi kenaikan glukosa darah (area di bawah kurva) lebih dari 50% tanpa mengubah respons insulin [ Gannon et al, 2002 ]
Dalam sebuah penelitian pada hewan, tikus diabetes yang diobati dengan glisin selama enam bulan menunjukkan konsentrasi glukosa, kolesterol total, triasilgliserol, dan hemoglobin terglikasi yang jauh lebih rendah dibandingkan tikus kontrol diabetes. [ Alvarado-Vásquez dkk, 2003 ]
Dalam uji coba selama 3 bulan, pasien diabetes tipe 2 yang diberi 5 gram glisin per hari mengalami penurunan HbA1C dan sitokin proinflamasi yang signifikan, dan juga peningkatan IFN-gamma yang signifikan.
Pengobatan dengan glisin kemungkinan besar mempunyai efek menguntungkan pada respons imun bawaan dan adaptif serta dapat membantu mencegah kerusakan jaringan yang disebabkan oleh peradangan kronis pada pasien diabetes tipe 2.
Cruz dkk 2008
Penelitian pada hewan pengerat baru-baru ini menunjukkan bahwa suplementasi glisin tinggi mengurangi efek dari diet tinggi sukrosa, meningkatkan fungsi mitokondria di hati dan mengoreksi “peningkatan tekanan darah, menormalkan trigliserida serum dan insulin, mencegah peningkatan massa lemak perut dan, pada gilirannya. pembuluh darah, meningkatkan glutathione, menurunkan stres oksidatif dan menormalkan vasodilatasi yang bergantung pada endotelium,” yang sangat mengesankan para penulis sehingga mereka memberi judul makalah mereka Manfaat kardiometabolik dari glisin: Apakah glisin merupakan 'penangkal' fruktosa makanan? [ McCarty & DiNicolantonio, BMJ, 2014 ]
Tabel yang merangkum studi metabolisme glisin
Glycine protects cells
Glycine protects against shock caused by hemorrhage, endotoxin and sepsis, prevents ischemia/reperfusion and cold storage/reperfusion injury to a variety of tissues and organs including liver, kidney, heart, intestine and skeletal muscle, and diminishes liver and renal injury caused by hepatic and renal toxicants and drugs.
L-Glycine: a novel antiinflammatory, immunomodulatory, and cytoprotective agent., Zhong et al, 2003
Glycine’s ability to protect cells and prevent cell injury and death, has been robustly and repeatedly demonstrated over the last 28 years. The main mechanism appears to be glycine’s ability to “to stabilize porous defects that develop in the plasma membranes of ischemic cells, leading to leakage of macromolecules and subsequent cell death.” [Van den Eynden et al, 2009]
Glycine also exerts separate, but complimentary positive effects on inflammatory cell signalling that can combine to protect and prevent tissue damage in a variety of disease states. [Weinberg et al. 2016]
Glycine has the ability to protect cells from ischaemia–reperfusion injury, including neurons, intestinal, skeletal, heart, kidney and liver cells [Pan et al, 2009] which give it a role in organ transplant.
- Protection from hypoxia (lack of oxygen)
- Protection from iron-induced injury
- Protection from re-warming after cold preservation of both kidneys and livers awaiting transplantation
- Protection from bacterial and fungal toxins that target cell permeability barriers
- Protection from ATP (i.e. cellular energy) depletion
Glycine Therapy to Prevent Organ Transplantation Failure
“These days’ non-heart-beating donors are gaining more importance as good source of transplantable organs due to severe shortage of donor organs for clinical use. The grafts from non-heart-beating donors are treated with 25 mg/kg of glycine during normothermic recirculation to decrease reperfusion injury to endothelial cells and parenchymal cells after organ transplantation [55]. After human liver transplantation glycine is intravenously infused to minimize the reperfusion injury. Before implantation, recipients are given 250 ml of 300 mM glycine for one hour and after transplantation 25 ml of glycine is given daily.” [Abdul Razak, 2017]
In contrast to the above, there have been calls to abandon the use of glycine irrigation during TURP (trans urethral resection of the prostate) as it appears to lead to worse outcomes when compared with alternative irrigation solutions. [Hahn, 2013]
Glycine protects the stomach and gut
Intestines
Glycine receptors are expressed on the lining of the intestines. When glycine is present in the intestines these receptors stimulate the release of the hormone glucagon-like peptide-1 (GLP-1), which has a range of effects including boosting fatty acid oxidation (i.e. using fat for energy production) in the liver, and satiety signalling (reducing appetite).
Glycine receptors have also been shown to improve the mucosal barrier, protect the gut from inflammation, oxidative stress and a variety of toxins, by a variety of mechanisms, including increased production of glutathione, our most potent antioxidant. In an animal study glycine protected rat intestines from damage in a chemical model of colitis. [McCole, 2010]
Glycine may be important to the proper development of the intestines. A study in piglets demonstrated that dietary supplementation was necessary to ensure optimal intestinal development in piglets. They also noted that reduced concentrations of glycine in the lumen of the small intestine were associated with gut dysfunction in low-birth-weight piglets. [Li et al, 2016]
Gastric Ulcers
Glycine can protect the stomach from overproduction of acid such as occurs in gastric ulcers, in a dose dependent manner. Pretreatment with glycine has been shown to protect the stomachs from ulceration by injury and alcohol. These results have led researchers to state that “glycine possesses significant anti-ulcer and cytoprotective activity.” [Tariq & Moutaery, 1997]
Alcohol
Glycine protects the liver from alcohol toxicity, reduces blood alcohol levels, and reduces the accumulation of free-fatty acid levels in the brain and liver caused by alcohol intoxication. Glycine supplementation also reduced the lipid levels associated with alcoholic dislipidemia [Abdul Razak, 2017]
Leaky gut and endotoxins
Glycine is able to reduce leaky gut, thereby reducing bacterial gut toxins (endotoxins), such as lipopolysaccharides, passing into the blood. Glycine is further, able to bind such proteins and reduce the inflammatory response associated with them. [Xin Zhou et al, 2016]
The ability of glycine to reduce gut permeability may have benefits in autoimmune conditions, but there has been no research to date.
Anti-oxidant and detoxification effects
When considering antioxidants, many people think about vitamin A, C, E and selenium. However, more important than these dietary antioxidants is your body’s own natural antioxidant system, which produces a range of biochemical of which glutathione is arguably the most important and is found in every part of the body.
Glutathione production
Glutathione production is limited by a number of factors which can seriously compromise an individuals detoxification potential and anti-oxidant response.
Glutathione is synthesised from the amino acids glutamate, cysteine, and glycine, but studies have shown that the rate of synthesis is primarily determined by levels of glycine in the tissue. If there is insufficient glycine available the glutathione precursor molecules are excreted in the urine. Vegetarians excrete 80% more of these precursors than their omnivore counterparts indicating a more limited ability to complete the synthesis process. [McCarthy et al, 2018]
Supplementing with glycine has been shown to increase the rate of glutathione synthesis while reducing markers of oxidative stress and protecting associated tissue from damage [Gould & Pazdro, May 2019]
However, there are other ways that glycine improves antioxidant response, for example by increasing the liver’s production of pyruvate which is an effective free-radical scavenger.
Nrf2 signalling
The body’s built-in antioxidant system is dynamic, being cranked up under certain circumstances (such as during an infection) and down regulated under others. A key regulatory pathway is controlled by Nrf2 signalling. In many glycine supplementation studies, Nrf2 has been shown to be up-regulated by glycine supplementation. [Wang, 2019]
Glycine has been shown to reduce the toxic effects of heavy metals such as lead and cadmium on the liver and kidneys. In one study it was shown that glycine supplementation significantly reduced lead accumulation in bone and completely restored the structural liver damage associated with lead poisoning . [Alcaraz-Contreras, 2011; Shaikh and Tang, 1999]
In a cadmium toxicity study glycine was able to counteract many of the effects significantly reducing the inflammatory response of macrophages.
[Our] findings support the immense antioxidant role of glycine
Okoto & Awhin, Food and Chemical Toxicology, 2010
Glycine’s role in detoxification
So we have seen that glycine can support detoxification indirectly via up-regulating Nrf2 signalling and stimulating glutathione production, however, recent evidence has shown that glycine has a direct detoxification pathway of its own.
Glycine is able to bind a number of toxins and toxic metabolites (e.g., benzoate, derivatives of branched chain amino acids (BCAA), β-oxidation intermediates and metabolites of polyphenols). In doing so it makes these compounds less toxic and more soluble, enabling them to be excreted in the urine. [Irwin et al, 2016, Alves at al, Nutrients, 2019]
Bile
Glycine and taurine are two of the amino acids involved in the formation of bile acids. Bile is made in the liver and stored in the gall bladder, ready for appropriate deployment when dietary fat is detected. Of the two, glycine is the more important and the formation of the glycine conjugated bile acids has been shown to be limited by the availability of glycine. The bile acid cycle is one of the body’s main detoxification pathways. [Alves at al, Nutrients, 2019]
Glycine’s heart health benefits
There is growing evidence of a protective effect of glycine on coronary heart disease.[Wittemans et al, 2019]
Studies comparing individual amino acid intake to incidence of cardiovascular outcomes identify certain amino-acids as “protective”. High intakes of the potentially cardioprotective amino acids (arginine, cysteine, glutamic acid, glycine, histidine, leucine and tyrosine) correlated with a 74% decreased incidence of CVD events, whereas high intake of glutamic acid and proline correlated with a 30% increased risk. [Mirmiran et al, 2017]
Furthermore, blood glycine levels negatively correlate with acute myocardial infarction risk and are associated with a favourable lipid and inflammatory blood profile.
A key mechanism of glycine is its ability to activate glycine-gated chloride channels which are found on many cells including on Kupffer cells (liver cells), macrophages, lymphocytes, platelets, cardiomyocytes (heart cells) and endothelial cells (including in artery walls). Supplemenal glycine has been found to exert “anti-inflammatory, immunomodulatory, cytoprotective, platelet-stabilising and anti-angiogenic effects in rodent studies” [McCarty & DiNicolantonio, BMJ, 2014]
Glycine supplementation shows many of the “blood thinning” benefits of aspirin, but without the side-effects:
- Reduced platelet aggregation
- Increased bleed time
- Improved microcirculation
- Reduced inflammation
Hence in relation to conditions such as cardiovascular disease, stroke and sudden death researchers are saying:
…dietary supplementation with glycine should be of immense benefit in preventing diseases where increased platelet aggregation and thrombosis are involved.
Schemmer et al, 2012
Young at heart
Aging is associated with a deterioration in heart function, including arterial stiffening and diastolic dysfunction. Furthermore, the mitochondria of old hearts can no longer metabolise fatty acids effectively so glucose becomes their primary energy source. Remarkably, glycine supplementation may help restore some of the heart’s youthful qualities.
In a study of old mice, a supplement of glycine and N-acetyl cysteine was found to improve many aspects of heart function (diastolic function, increasing peak early filling velocity, and reducing relaxation time, left atrial volume, and left ventricle end diastolic pressure), as well as stimulating youthful gene expression and function in heart mitochondria. The heart cells of supplemented mice regained the ability to burn fatty acids. Interestingly, N-acetyl cysteine alone failed to produce a majority of these observations [Cieslik et al, 2018]
Cholesterol
Higher glycine levels are associated with better blood lipid and inflammatory markers (higher HDL-cholesterol and apolipoprotein A1, lower triglycerides, apolipoprotein B and C-reactive protein) [Rom et al, 2019]
The typical pattern of dyslipidemia associated with metabolic syndrome, involves the liver overproducing triglyceride-rich LDL. In a 2012 paper a study demonstrated that glycine can normalise liver production of triglycerides, potentially via glycine’s effects on the central nervous system, normalising liver signalling. [Yue et al, 2012]
In a more recent study, rats with metabolic syndrome fed a 1% glycine diet had reduced body weight, body fat, blood pressure, triglycerides, leptin, insulin and total fatty acids. [López et al, 2016]
Ageing and Longevity
It has been observed that diets high in glycine lead to a 5% increased lifespan in rodents. Intriguingly, this effect is similar to the lifespan extension that can be induced through a diet low in methionine. [Miller 2019]
In the body, the metabolism of methionine and glycine are closely intertwined, with glycine providing the final step in the breakdown of methionine. Glycine is thus consumed in the process of detoxifying methionine.
This probably explains why meat eaters, despite consuming more glycine, have similar blood levels as vegetarians: The higher level of methionine in a meat-based diet leads to more glycine being ‘used up’.
Glycine counteracts the effects of AGE/RAGE
Part of the ageing process is attributable to the damage done when glucose reacts with proteins in the body to form advanced glycation end products (AGEs). Such glycation damages proteins and produces toxic byproducts. Glycation is responsible for the gradual deterioration of collagen as we get older, leading to a loss of elasticity.
Glycation affects many other parts of the body, especially with long-lived tissue where AGEs can accumulate over time, such as the lens and cornea of the eye, cartilage in joints and blood vessels. AGE formation in the body is increased by raised blood glucose such as happens following a high carb meal and especially in diabetes where blood glucose is poorly regulated. Compounds formed by such glycation (AGEs) trigger a cycle of inflammation and oxidative stress. AGEs are key factors in complications associated with Alzheimer’s disease, cataracts, atherosclerosis and kidney aliments among others. [Chilukuri, 2018]
Glycine supplementation has been shown to markedly reduce glycation in diabetic rats, reducing the inflammation and oxidative stress associated with it. Protective effects were also observed in the aorta and heart function of rats fed glycine. [Wang et al Mar 2019]
Glycine has been shown to counteract the formation of cataracts by preventing the glycation of lens proteins. [Bahmani, 2012] In another study, glycine supplementation at 20g per day was able to improve the hearing of diabetic patients. [Muñoz-Carlin Mde et al, 2010]
Glycine’s Anti-Cancer Properties
Cancer cell proliferation makes use of one-carbon metabolism which is highly dependent on serine/glycine. Because serine and glycine can be interconverted it may be expected that either could fuel cancer proliferation. However, it appears that while dietary serine increases cancer cell proliferation, glycine does not. Diets that restrict the amino acid serine have been shown to have anti-cancer benefits, but not those that restrict glycine. [Labuschagne, 2014]
In fact glycine has been shown to have a number of anti-cancer effects. Its primary role appears to be by reducing the growth of blood vessel on which tumours depend (i.e. supressing angiogenesis) as well as reducing epithelial cell proliferation.
Evidence from studies
A mouse study of melanoma found a 65% reduction in tumour mass, and 70% fewer blood vessel in the tumor among mice fed a 5% glycine diet. [Rose et al, 1999]
The same team also conducted a rat study which showed that dietary glycine had the ability to significantly suppress liver tumour development. [Rose et al, 1999] Although other researchers have pointed out that this study is unlikely to be directly relevant to humans because of the way the tumours were induced [Corton, 2018]
A 2016 paper in Amino Acids reported that glycine completely neutralised angiogenesis (growth of new blood vessels) in colorectal cancer cell lines in a dish. They also demonstrated that glycine supplementation reduced tumour size by 35% and blood vessels by 55% in colorectal cancer in rats [Bruns et al, 2016]
Dietary glycine has been shown to decrease tumour volume and vascularisation in a model of colorectal cancer with liver metastasis, without decreasing the action of chemotherapy. [Maneikyte, 2019]
Dosing & Contraindications
Dosing
- Measurable benefits have been observed from as little as 1-2 g of supplemental glycine per day.
- For improved sleep 3-5 g before bed has been shown to be effective.
- Limitations on collagen production increase from age 25. For older adults a total of 10g/day appears to be a sensible target dose. This could be spread across the day e.g. 2-3g with each meal, 3g before bed.
- Larger doses for specific conditions are probably best taken under the supervision of a practitioner.
Dosing in studies
| Dosage (duration) | Effects | Side-effects |
| 1-2g per day under tongue (5 days) | Reduced stroke mortality | well tolerated |
| 5 g per day (3 months) | Improved blood glucose, reduced inflammation | well tolerated |
| 5 g per meal (4 weeks) | Improved insulin sensitivity [ref] | well tolerated |
| 5 g per meal (3 months) | Improved Metabolic Syndrome [ref] | |
| 3 – 9 g before bedtime (3 days) | Improved sleep [ref] | Minor digestive symptoms at upper dose |
| 20 g/day | Improved auditory response in diabetics | none reported |
| 60 g/day (5 years) | Psychosis treatment (case report) Well tolerated [ref] | well tolerated but only one case study |
Glycine absorption and blood levels
Glycine is rapidly absorbed in the intestines. It leads to spike in blood levels after about 30 minutes when taken on an empty stomach, a little longer if eaten with food. Glycine blood levels then remain raised for a further 3 hours.
The graph above shows how 1 g oral glycine leads to a peak 60% rise in blood glycine levels after 30 minutes. Taking larger quantities will lead to a greater increase: for example, 5g leads to a 300% increase. Taking glycine with a meal, especially carbohydrates, has been shown to suppress the rise by about 10% and increase the time taken to return to baseline. [Gannon et al, 2002]
Glycine for exercise recovery
As blood glycine levels peak soon after ingestion, glycine can be considered a “fast protein” for exercise recovery. Hence, for post-exercise tendon, ligament and joint repair/remodelling glycine should be taken immediately after exercise, to maximise collagen synthesis.
General supplementation
For most people who are supplementing glycine for general health benefits, including improved blood sugar, cell protection, and anti-aging effects, taking a small dose several times per day is probably sufficient. Many supplement manufacturers recommend 1 g three times per day. From the studies considered above 2-3 g with each meal and 3 g before bed might be suitable protocol.
Cautions
Pregnancy and Infants
There are no studies considering glycine supplementation during pregnancy or for infants. A trial to determine glycine needs in pregnancy is currently registered with Clinicaltrials.gov, but has yet to report.
EDIT: The results have now been published: Glycine, a Dispensable Amino Acid, Is Conditionally Indispensable in Late Stages of Human Pregnancy, (Betina F Rasmussen et al, 2021)
Contraindications
Clozapine (Clozaril) is used to help treat schizophrenia. Taking glycine along with clozapine (Clozaril) might decrease the effectiveness of clozapine (Clozaril). It is not clear why this interaction occurs yet. Do not take glycine if you are taking clozapine (Clozaril). (WebMd)
Maximum Dose
A maximum tolerable daily intake for some adults is as low as 15 g of glycine per day, or 9 g in a single dose, where minor digestive disturbances were reported by some (soft stools and mild digestive discomfort). Others have been able to tolerate 60g per day as two 30g doses without discomfort. No toxicity has been reported for doses up to 60g (adult). One case study showed no toxic effects at this daily dose for five years. [Cleveland et al, 2010] These limits are likely to vary from person to person.
Toxicity
A study in rats found no deaths nor evidence of toxicity when feeding at the maximum protocol for toxicology studies of 2 g/kg body weight per day for 4 weeks. The LD50 dose for rats is quoted as being close to 8g/kg/day [Shibui et al, 2013] Taking into account the fact that large animals have slower metabolisms and therefore lower tolerance than small animals, and to include a safety margin, Anroop & Jacob recommend calculating a human equivalent by dividing rat doses by 6.2. This suggests the following reasonable upper safe dose and reasonable lower toxic dose.
| Daily intake | by body weight per day | for a 65kg adult per day |
| Reasonable upper safe limit* | 0.3 g/kg | 21 g |
| Reasonable lower toxic limit* | 1.3 g/kg | 84 g |
*These are not official values, but simply ones I calculated from data and assumptions given in the preceding paragraph.
Intravenous toxicity
The only documented cases of glycine toxicity and death in humans have been those associated with complications during surgery, where a solution of glycine used to irrigate the site of the operation entered systemic circulation in significant volume (often amounting to litres of fluid!) Not very relevant to normal oral supplementation, but I include it here for completeness.
Glycine solution is widely used for irrigation during endoscopic (keyhole) surgery. A complication of such procedures occurs when large volumes of the 1.5% glycine solution become inadvertently absorbed into circulation. This can lead to toxic levels of glycine in the blood which may cause serious complications including transient blindness or even death, although such effects are partly due to dilution of electrolytes, not just the glycine concentration. [Olsson & Hahn, 1998] Such results can be repeated in animals via intravenous infusion of 1.5% glycine solution.
Normal plasma glycine levels are 0.2–0.3 mmol/L. In non-fatal cases of irrigation fluid absorption (which may, nonetheless involve serious side effects such as transient blindness), blood levels of glycine rise to 5–8 mmol/L [Dwivedi, 2018]. Compare this to the blood levels induced by oral supplements where 1 g on an empty stomach typically increase blood levels of glycine by 0.1 – 0.2 mmol/L. In one study an approximately 5 g single, oral dose, raised blood glycine levels to 0.9 mmol/L [Gannon et al, 2002] with no reported adverse effects. Even at the extreme upper end of supplementation, the literature documents one case study where a patient took two 30g doses per day, plasma levels rose to approximately 3 mmol/L which was well tolerated, despite being close to the toxic threshold [Cleveland et al, 2010]
Further Info
Saya sangat merekomendasikan podcast berikut bersama Chris Masterjohn: Mengapa Anda Membutuhkan Glycine: Diskusi Panel
Saya yakin Anda tertarik untuk menggunakan asam amino yang sangat aman dan masuk akal ini sebagai suplemen untuk diet Anda. Oleh karena itu, saya akan menyimpannya mulai sekarang di klinik saya dan menggunakannya dalam pekerjaan saya dengan pasien.
GLYCINE SEKARANG DALAM SAHAM DI KLINIK SAYA
Terima kasih!
Terima kasih atas survei penelitian yang menyeluruh dan terperinci. Paul Saladino membicarakan beberapa hal ini dalam berbagai pembicaraan dan wawancara. Itulah sebabnya judul artikel ini menarik perhatian saya, karena saya baru saja menonton video dia menekankan pentingnya glisin. Dia punya buku yang akan diterbitkan. Menarik untuk disimak apa yang beliau bahas di dalamnya.
dimana ini tersedia?
Saya akan segera menyimpannya di klinik saya Alice. Anda dapat mengirimi saya pesan melalui halaman 'hubungi saya', dan saya akan dapat menjawabnya secara pribadi. Semoga semuanya baik-baik saja denganmu. Salam hangat dari kami!
Baca saja ini- betapa brilian dan menyeluruhnya dan saya pasti ingin glisin jika Anda memiliki stok Afifah.
Akan melakukan Emma. Senang Anda menyukai artikelnya. Kami menemukan penelitian mengenai subjek ini sangat menarik.
Akan ada lebih banyak lagi yang ditambahkan ke artikel ini segera, jadi nantikan itu. Jika Anda berlangganan blog, Anda akan mendapat pemberitahuan saat penambahan itu dipublikasikan.
Saya harap Anda menyukai artikel dan resep lainnya juga.
Senang bertemu Anda hari ini, dan nantikan waktu berikutnya.
When using it as a sweetner what could destroy the aminoacid?
Do you think it could be used with lemon on a lemonade? Or baked on a muffin?
You do mention “on a hot drink” but I was wondering how much temperature or acidity (or something else) can it stand…
All good questions anamado, and I am sorry to say I cannot answer them with confidence as I have not been able to find that information myself yet. However, I don’t think that acidity (as long as it is not extreme) will make any difference to glycine, nor cooking with it, as it is just an amino acid, not a complex folded protein that could change shape (known as becoming de-natured), so I think it’s probably safe to play with, but not to extremes.
I tried supplementing with glycine for the first time just yesterday. Foolishly, I suppose, I mixed the whole 10g into a mug of cool water and sipped it all down within the space of a few minutes. A little later I experienced the low-blood pressure feeling familiar to me from my tendency to faint at the sight (or even description) of blood: light-headedness and slight nausea. Today, I took half the dose, five grams, in the same amount of water. I felt fine. I measured my blood pressure just before and about twenty minutes after I started imbibing the dose. Results: before – 130/80; after – 120/70. Not quite a scientific trial, but intriguing.
Great that you are doing some experiments on yourself, but, people who know they are a bit ‘volatile’ in their reactions should always go gently, even with glycine.
Glycine is extremely well tolerated, as it is only an amino acid, but we humans can be pretty surprising in their sensitivities, so always go gently.
The BP readings are interesting. Keep an eye on that and see what, if anything, develops. Neither of your BP measurements are in any way negative, but interesting that both systolic and diastolic dropped.
Correction: my first dose was *twenty* grams, not ten (and the second dose was ten, not five). Misidentification of a scoop…just as well I don’t work in a dispensary.
Thanks for putting that straight.
So 20g at once might have dropped your BP rather suddenly (which of course could have bad consequences if one already had low BP) but you corrected this, and are now on 10g daily, as one dose, and that is fine?
Yes: 10g daily in one dose, on an empty stomach, is absolutely fine. I may change to subdivided doses, but not because of any ill effects. And I think I’m already sleeping better than ever.
That’s encouraging.
I have been using glycine for 3 days – 1g with a collagen supplement, 1g with lunch and 1.5g with some natural yoghurt 90 mins before bed and it’s helped with my sleep already. To be fair I’m very sensitive and reactive but will def order some more from Afifah when I run out
If glycine has a blood thinning effect, is it safe to take with other supplements with a blood thinning effect like garlic?
Hi Graham, to my knowledge this has not been determined. Sorry I can’t offer anything definitive.
Ok, probably best to err on the side of caution then.
Yes, caution, but it is just an amino acid, not a drug. The chance of anything sudden or major taking place is, I’d say, slight. If you go gently, starting low and observing, as with any thing new you introduce, you should be able to adjust things to suit your unique physiology.
I’ve been experimentally taking glycine at about 8 grams per day for a couple of weeks now. I’ve noticed two effects so far:
1) I’ve noticed a substantial improvement in my eyesight, which has become much sharper (presumably the glycine might be reducing some inflammation in my eyes?)
2) I’ve been much more sleepy than usual, though this has worn off slightly.
Can I use glycine pre workout, Post workout and before bed
If I use glycine pre workout, Post workout and before bed how much do I use per dose for optimal benefits
Hi Grant, as far as I know there is no concern about when one takes glycine, i.e. in relation to exercise or bed or anything else. I think it reasonable to take it when other food is being ingested, and that goes for all supplements, as the system is expecting nutrients when we eat, and is ready to absorb them. The standard daily dose as suggested in the research is 10g, and this can be divided into thirds, or taken at one go. People find what works for them. Read the article again, and follow some of the links, to get a better feel for how you want to use it. Let me know how you get on.
I’m confused because the bottle says it is a 1000 mg
How do I cut down to 10 g. I know I can’t figure the potencies. Thanks for any help
1,000 mg is equal to 1 gram. So take 10
If my recipe calls for 1/2 cup sugar, how much glycine would I substitute?
Hi Elinor, this is a good question.
I have found that glycine adds varying amounts of sweetness, depending on the dish it is added to. I do not know quite what to make of this, so I suggest trying out the recipe with half the amount of glycine to the sugar in the recipe, initially, or less than half, and see if you like the results.
If your aim is to get glycine into your body and that of your family, then you will be freer with it. If you are weening yourself off the sweet taste, you will use less.
Glycine is not a sugar, as you know, it is an amino acid, and the research, as shown in the article if you click on the links, mostly recommends 10g daily for adult, i.e. two teaspoons. In my experience those with injuries such as torn Achilles tendons need 3 tsp per day for rapid healing, and back to two once all is resolved.
I hope that helps.