Skip to main content
SkinCited

Green Tea Extract ： UV Protection (Internal Photoprotection)

B

Research suggests oral green tea polyphenols (250-1,080 mg/day) increased MED by approximately 25%, providing internal photoprotection through antioxidant and anti-inflammatory mechanisms.

<\/script>\n
`; }, get iframeSnippet() { const domain = 'skincited.com'; const params = 'ingredient\u003Dgreen\u002Dtea\u002Dextract\u0026condition\u003Duv\u002Dprotection'; return ``; }, get activeSnippet() { return this.method === 'script' ? this.scriptSnippet : this.iframeSnippet; }, copySnippet() { navigator.clipboard.writeText(this.activeSnippet).then(() => { this.copied = true; setTimeout(() => { this.copied = false; }, 2000); }); } }" @keydown.escape.window="open = false" @click.outside="open = false">

Embed This Widget

Style



      
      
    


    
    

      Widget powered by
      .
      Free, no account required.
    

  




    








    

        

            B

        

        

            
結論

            
            
Research suggests oral green tea polyphenols (250-1,080 mg/day) increased MED by approximately 25%, providing internal photoprotection through antioxidant and anti-inflammatory mechanisms.

            
            
        

    











    
    

        
        

            

  
Key Statistics





            


    

        
8

        
研究数

    

    

        
450

        
参加者数

    

    

        
            
            ↑
            
        
        
Positive

    

    

        B

        
グレード

    




        


        
        

        
        
        

            

  
Dosage & Usage





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


            
            

                
一般的な使用量

                

                    
                    

                        
general:

                        
250-500 mg/day green tea extract

                    

                    
                    

                        
skinhealth:

                        
250-500 mg/day standardized to 50-90% EGCG

                    

                    
                

                
                

                    上限量： 800 mg EGCG/day (doses above may cause hepatotoxicity in rare cases)
                

                
            

            

            

            
            

                推奨摂取タイミング： With meals (may cause nausea on empty stomach); avoid with iron-rich foods
            

            
        

        

        
        
        

            

  
Safety & Side Effects





            

                
                

                    
報告されている副作用

                    
    
                        
                        
  • 
                            ⚠
                            Nausea (especially on empty stomach)
                        
    • 
                        
                        
  • 
                            ⚠
                            Insomnia and jitteriness (caffeine content)
                        
    • 
                        
                        
  • 
                            ⚠
                            Rare hepatotoxicity at high doses (> 800 mg EGCG/day)
                        
    • 
                        
                        
  • 
                            ⚠
                            Reduced iron absorption
                        
    • 
                        
                    

                

                

                
                

                    
既知の相互作用

                    
    
                        
                        
  • 
                            ●
                            Iron supplements (reduces absorption — separate by 2+ hours)
                        
    • 
                        
                        
  • 
                            ●
                            Stimulant medications (additive caffeine effects)
                        
    • 
                        
                        
  • 
                            ●
                            Blood thinners (may have mild antiplatelet effects)
                        
    • 
                        
                        
  • 
                            ●
                            Hepatotoxic medications (potential additive liver stress at high doses)
                        
    • 
                        
                    

                

                

                
                

                    

                        耐容上限摂取量： 800 mg EGCG/day (doses above may cause hepatotoxicity in rare cases)
                    

                

                
            

            

                サプリメントの摂取を開始する前に、必ず医療専門家にご相談ください。
            

        

        

        
        
        

            

  
Frequently Asked Questions





            




    
    

        
            Does Green Tea Extract help with UV Protection (Internal Photoprotection)?
            
        
        

            Based on 8 studies with 450 participants, there is moderate evidence from clinical studies that Green Tea Extract may support UV Protection (Internal Photoprotection) management. Our evidence grade is B (Good Evidence).
        

    

    
    

        
            How much Green Tea Extract should I take for UV Protection (Internal Photoprotection)?
            
        
        

            Studies have used various dosages. A commonly studied range is 250-500 mg/day green tea extract. Always consult your healthcare provider before starting any supplement regimen.
        

    

    
    

        
            Are there side effects of Green Tea Extract?
            
        
        

            Reported side effects may include Nausea (especially on empty stomach), Insomnia and jitteriness (caffeine content), Rare hepatotoxicity at high doses (> 800 mg EGCG/day), Reduced iron absorption. Most side effects are mild and dose-dependent. Consult your doctor if you experience any adverse reactions.
        

    

    
    

        
            How strong is the evidence for Green Tea Extract and UV Protection (Internal Photoprotection)?
            
        
        

            We rate the evidence as Grade B (Good Evidence). This rating is based on 8 peer-reviewed studies with 450 total participants. The overall direction of effect is positive.
        

    

    




        

        

        
        
        

            

  
Related Evidence





            

                
                
                

                
                

                    
Green Tea Extract 他の症状・状態について

                    

                        
                        
                            Acne
                            D

                        
                        
                    

                

                
            

        

        

    


    
    












    

        FDAに関する免責事項:
        これらの記述は米国食品医薬品局（FDA）による評価を受けていません。本ウェブサイトの製品および情報は、疾病の診断、治療、治癒、または予防を目的としたものではありません。表示されているエビデンスグレードは、公開された査読済み研究の分析に基づいており、医療上の助言を構成するものではありません。サプリメントの摂取を開始する前に、必ず医療専門家にご相談ください。