Your gut handles small amounts of fructose just fine, but when you eat too much, it gets overwhelmed and lets the extra pass through to your liver.

What we've found so far is that the small intestine plays a key role in processing fructose, but it may become overwhelmed when large amounts are consumed [1]. Our analysis of the available research suggests that at low to moderate intakes, the gut effectively metabolizes fructose before it reaches the liver [1]. However, when higher doses are consumed, this capacity appears to be exceeded, allowing more fructose to pass through to the liver [1]. The evidence we’ve reviewed leans toward the idea that the small intestine acts as a gatekeeper for fructose [1]. Under normal eating conditions, it can convert or absorb much of the fructose you consume. But when you eat or drink large amounts—such as from sugary beverages or processed foods—this system may reach its limit [1]. Once that happens, more fructose escapes into the bloodstream and travels to the liver for processing [1]. We don’t yet know exactly how much fructose it takes to overwhelm this system in most people, since individual responses may vary. But based on what we’ve reviewed so far, the body’s ability to handle fructose isn’t unlimited [1]. The idea that excess fructose bypasses the gut and reaches the liver is supported by the evidence we’ve analyzed, with 20.0 supporting assertions and none that refute it [1]. Still, our current analysis is based on a limited number of assertions, and we expect our understanding to improve as more research becomes available. We’re not claiming this is the final word—just what the evidence shows up to now. Practical takeaway: Your body can handle small amounts of fructose just fine, but drinking or eating a lot at once—like from soda or candy—might send more sugar to your liver than your gut can manage.