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SleepCited

Glycine for Sleep Onset Difficulty

D

Based on 1 study with 5 total participants. Results are mixed across studies.

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The Bottom Line

            
            
There is currently not enough evidence to determine whether glycine helps you fall asleep faster — only one very small study with mixed results has been identified.

            
            
            
    
                
                
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                    Only 1 study with 5 participants — far too little to draw conclusions
                
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                    Grade D evidence indicates very limited research on this specific use
                
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                    The available study was not specifically designed to test glycine for sleep onset
                
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                    Glycine's broader sleep benefits (see insomnia evidence) do not automatically apply to sleep onset
                
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Key Study Findings





    

        
        

            

                
                    Case Reports
                
                
                n=5
                
                
                
            

            
                Human prion disease with a G114V mutation and epidemiological studies in a Chinese family: a …
            
            

                
                Dose: None
                
                
                vs: Placebo
                
                
                
                Effect: None
                
                
                None
                
            

            
        

        
    







    
    

        
        

            

  
Key Statistics





            


    

        
1

        
Studies

    

    

        
5

        
Participants

    

    

        
            
            ↔
            
        
        
Mixed

    

    

        D

        
Grade

    




        


        
        
        

            

  
Referenced Papers





            

                
                

                    

                        
                            Human prion disease with a G114V mutation and epidemiological studies in a Chinese family: a case series.
                        
                        
                            
                                Other
                            
                            
                            
                        
                    

                    

                        Journal of medical …
                        2008
                        
                        33 citations
                        
                    

                

                
            

        

        

        
        
        

            

  
Dosage & Usage





            
mg = milligrams · mcg = micrograms (1,000× smaller) · IU = International Units


            
            

                
Commonly Used Dosages

                

                    
                    

                        
sleep:

                        
3 g, 1 hour before bed

                    

                    
                

                
                

                    Upper limit: Not established; studied up to 9 g/day
                

                
            

            

            
            

                
Dosages Studied in Research

                

                    

                        
                            

                                Dosage
                                Duration
                                Effect
                                N
                            

                        
                        
                            
                            

                                None
                                --
                                
                                    
                                    Neutral
                                    
                                
                                5
                            

                            
                        
                    

                

            

            

            
            

                Best taken: 1 hour before bed
            

            
        

        

        
        
        

            

  
Safety & Side Effects





            

                
                

                    
Reported Side Effects

                    
    
                        
                        
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                            ⚠
                            Nausea
                        
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                            Soft stools
                        
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                            Mild drowsiness
                        
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Known Interactions

                    
    
                        
                        
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                            ●
                            Clozapine — glycine may reduce effectiveness of this antipsychotic
                        
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                            Antihypertensives — potential additive blood pressure lowering
                        
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                        Tolerable upper intake: Not established; studied up to 9 g/day
                    

                

                
            

            

                Always consult your healthcare provider before starting any supplement.
            

        

        

        
        
        

            

  
Frequently Asked Questions





            




    
    

        
            Does Glycine help with Sleep Onset Difficulty?
            
        
        

            Based on 1 studies with 5 participants, there is preliminary evidence that needs more research that Glycine may support Sleep Onset Difficulty management. Our evidence grade is D (Very Early Research).
        

    

    
    

        
            How much Glycine should I take for Sleep Onset Difficulty?
            
        
        

            Studies have used various dosages. A commonly studied range is 3 g, 1 hour before bed. Always consult your healthcare provider before starting any supplement regimen.
        

    

    
    

        
            Are there side effects of Glycine?
            
        
        

            Reported side effects may include Nausea, Soft stools, Mild drowsiness. Most side effects are mild and dose-dependent. Consult your doctor if you experience any adverse reactions.
        

    

    
    

        
            How strong is the evidence for Glycine and Sleep Onset Difficulty?
            
        
        

            We rate the evidence as Grade D (Very Early Research). This rating is based on 1 peer-reviewed studies with 5 total participants. The overall direction of effect is mixed.
        

    

    




        

        

        
        
        

            

  
Related Evidence





            

                
                
                

                
                

                    
Glycine for other conditions

                    

                        
                        
                            Insomnia
                            A

                        
                        
                    

                

                
            

        

        

    


    
    












    

        FDA Disclaimer:
        These statements have not been evaluated by the Food and Drug Administration. The products and information on this website are not intended to diagnose, treat, cure, or prevent any disease. The evidence grades presented are based on our analysis of published peer-reviewed research and do not constitute medical advice. Always consult your healthcare provider before starting any supplement regimen.