Eating a lot of fructose might hurt male fertility in mice and rats by causing inflammation, stress in the body, and cell damage in the testicles, leading to lower testosterone and worse sperm health.

What we've found so far suggests that high fructose intake may be linked to lower male fertility in rodents. Our current analysis is based on limited evidence, but what we’ve reviewed points in a specific direction. We analyzed one assertion from the available research and found that it supports a possible negative effect of high fructose consumption on male fertility in mice and rats [1]. According to this evidence, eating large amounts of fructose might trigger inflammation, increase oxidative stress, and cause cellular damage in the testicles [1]. These biological changes could be associated with reduced testosterone levels and poorer sperm quality in these animals [1]. At this stage, all the evidence we’ve reviewed leans toward a potential harm to male reproductive health in rodents when fructose intake is high. However, we only have one assertion to base this on, and no studies in our current review contradict it. That means our understanding is still very limited. We cannot say how strong this effect might be, under what conditions it occurs, or whether it would happen in other species — including humans. We don’t yet have enough evidence to draw broader conclusions or make recommendations beyond what’s shown in these rodent studies. Our analysis remains open to change as more data becomes available. Practical takeaway: In rodents, too much fructose might affect sperm and hormone health, but we need a lot more research to be confident in how — and how much.