What Happens to Your Body After Eating McDonald's?
                                
                                
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                                    4 min read                                
                            
                                According to a 2015 review, fast food is typically high in sugar, salt, saturated or trans fats, and processed preservatives, while often lacking beneficial nutrients like fiber. A single McDonald's meal can initiate a cascade of physical reactions within your body, both immediate and delayed, affecting everything from your energy levels and digestion to your long-term cardiovascular health.