Food Intervention with Folate Reduces TNF-α and Interleukin Levels in Overweight and Obese Women with the MTHFR C677T Polymorphism: A Randomized Trial
Jéssica Vanessa de Carvalho Lisboa, Marina Ramalho Ribeiro, Rafaella Cristhine Pordeus Luna, Raquel Patrícia Ataíde Lima, Rayner Anderson Ferreira do Nascimento, Mussara Gomes Cavalcante Alves Monteiro, Keylha Querino de Farias Lima, Carla Patrícia Novaes dos Santos Fechine, Naila Francis Paulo de Oliveira, Darlene Camati Persuhn, Robson Cavalcante Veras, Maria da Conceição Rodrigues Gonçalves, Flávia Emília Leite de Lima Ferreira, Roberto Teixeira de Lima, Alexandre Sérgio Silva, Alcides da Silva Diniz, Aléssio Tony Cavalcanti de Almeida, Ronei Marcos de Moraes, Eliseu Verly, Maria José de Carvalho Costa
Abstract
Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism associated with body fat accumulation could possibly trigger an inflammatory process by elevating homocysteine levels and increasing cytokine production, causing several diseases. This study aimed to evaluate the effects of food intervention, and not folate supplements, on the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in overweight and obese women with the MTHFR C677T polymorphism. A randomized, double-blind eight-week clinical trial of 48 overweight and obese women was conducted. Participants were randomly assigned into two groups. They received 300 g of vegetables daily for eight weeks containing different doses of folate: 95 µg/day for Group 1 and 191 µg/day for Group 2. MTHFR C677T polymorphism genotyping was assessed by digestion with HinfI enzyme and on 12% polyacrylamide gels. Anthropometric measurements, 24-h dietary recall, and biochemical analysis (blood folic acid, vitamin B12, homocysteine (Hcy), TNF-α, IL-1β, and IL-6) were determined at the beginning and end of the study. Group 2 had a significant increase in folate intake (p < 0.001) and plasma folic acid (p < 0.05) for individuals with the cytosine–cytosine (CC), cytosine–thymine (CT), and thymine–thymine (TT) genotypes. However, only individuals with the TT genotype presented reduced levels of Hcy, TNF-α, IL-6, and IL-1β (p < 0.001). Group 1 showed significant differences in folate consumption (p < 0.001) and folic acid levels (p < 0.05) for individuals with the CT and TT genotypes. Food intervention with folate from vegetables increased folic acid levels and reduced interleukins, TNF-α, and Hcy levels, mainly for individuals with the TT genotype.