The C677T polymorphism in the MTHFR gene is related to several significant biochemical changes, as dyslipidemia, changes in serum levels of homocysteine, folic acid, vitamin B12 and some oxidative stress markers such as the CAT and MDA, leading to a high risk of the emergence of cardiovascular disease (CVD). A diet containing antioxidants, especially folate, is characterized by being beneficial for individuals with this genetic alteration to possess anti-inflammatory function, act on and oxidative stress play an important gene function. The aim of this study was to evaluate the influence of the C677T polymorphism of the MTHFR gene and the effect of a diet containing folate on oxidative stress, lipid profile and homocysteine levels in adult women are overweight or obese. This is an intervention study, double-blind, held in a city in northeastern Brazil. The study included 48 adult women (20-59 years old) with BMI of 26.19 kg / m² and 49.64 kg / m², in which we evaluated the CAT levels, MDA, lipid profile, folic acid, homocysteine and vitamin B12 addition genotyping for the C677T polymorphism in the MTHFR gene and the food consumption by the food recall 24 hours, being divided by randomization into two groups received daily for 8 weeks, 300g vegetables rich in folate containing 191 ug and 90 ug of this nutrient.