Consuming high amounts of phytate, a compound found in plant foods, is linked to more zinc being eliminated in feces and less in urine, suggesting that phytate limits how much zinc the body absorbs...

We analyzed the available evidence and found that high phytate levels are linked to reduced zinc absorption. Specifically, 44 studies or assertions support the idea that when people consume foods rich in phytate—like whole grains, legumes, nuts, and seeds—more zinc appears in their feces and less shows up in their urine, which suggests the body is absorbing less of it [1]. This pattern has been consistently observed across multiple studies, with no evidence found to contradict it. Phytate binds to minerals like zinc in the digestive tract, making them harder for the body to take up. This doesn’t mean these foods are unhealthy—many are nutrient-dense and important for overall health—but it does mean that if your diet relies heavily on these foods and you’re at risk for low zinc, your body might not absorb as much as expected. What we’ve found so far leans toward phytate reducing zinc absorption, based on the consistent pattern of zinc being excreted rather than retained. However, the body can adapt over time, and other dietary factors—like eating meat or fermenting foods—may help offset this effect. We don’t yet know how much this matters for most people in real-world diets, since absorption can vary by individual, meal composition, and gut health. If you eat a lot of plant-based foods high in phytate and are concerned about zinc, pairing them with sources of vitamin C or fermented versions (like sourdough or tempeh) may help. But don’t avoid these foods—just be aware that absorption might be lower than expected.