Here we report that after subchronic oral administration, TBLF provoked antinutritional effects in rats resulting in a transient decrease of food intake and body weight in he first weeks. The final result was observed as a reduction in body weight gain respect to the control group. The digestion assay suggests that lectins from Tepary bean can remain intact into the digestive tract up to 72 h. CBC at 24 h post-administration showed an allergic-like response that disappeared after 4 weeks of treatment. Blood markers suggest no toxic effects and no alterations in the evaluated organs. Taking together, our results showed that TBLF provoke a reduction in body weight gain with no other remaining effects, suggesting compensatory mechanisms and good tolerability. More studies are needed to determine effects on nutrient availability and intestinal integrity after TBLF administration, especially in long-term assays and in different development stages.