title: Elderly women: homocysteine reduction by short-term folic acid supplementation resulting in increased glucose concentrations and affecting lipid metabolism (C677T MTHFR polymorphism).
abstract: OBJECTIVE
  Serum homocysteine levels show interindividual variation and are determined by nutritional factors, such as B-vitamin intake, and by age and genetic influences, such as the genotype of the methylenetetrahydrofolate reductase (MTHFR) gene. Recently, the relation between one-carbon and lipid metabolism has been shown. Therefore, we hypothesized that folic acid supplementation would not only decrease homocysteine concentrations but also affect lipid metabolism. The aim of the present study was to evaluate the impact of short-term folic acid supplementation on homocysteine and lipid metabolism in Polish women older than 60 y with different C677T MTHFR genotypes.
  
  
  METHODS
  One hundred twenty-two volunteers were supplemented with folic acid 400 μg/d for 8 wk. Folate intake was assessed using a food-frequency questionnaire. The serum homocysteine level was analyzed using high-performance liquid chromatography. Serum biomarkers were measured with a Vitalab Flexor biochemical analyzer. MTHFR genotyping was performed using the polymerase chain reaction restriction fragment length polymorphism method.
  
  
  RESULTS
  In the studied group, the MTHFR genotype frequencies were 0.14 for TT, 0.43 for CT, 0.43 for CC carriers. At baseline, the average folic acid and homocysteine concentrations were 12.16 ± 0.23 ng/mL and 7.94 ± 0.3 μmol/L, respectively. Folic acid supplementation lowered the serum homocysteine concentration. However, the dietary intervention also led to an increase in glucose concentrations (P < 0.01). The T-allele carriers had a larger waist circumference (P < 0.05) and a higher waist-to-hip ratio (P < 0.01).
  
  
  CONCLUSIONS
  In elderly women, a short-term, low-dose folic acid supplementation lowered the serum homocysteine level but also increased glucose concentrations. The C677T MTHFR polymorphism affects the waist-to-hip ratio and lipid metabolism.
authors.affiliation: Department of Human Nutrition and Hygiene, Poznań University of Life Sciences, Poznań, Poland. agata@jay.up.poznan.pl
authors.forename: Agata
authors.initials: A
authors.lastname: Chmurzynska
authors.forename: Anna M
authors.initials: AM
authors.lastname: Malinowska
authors.forename: Jolanta
authors.initials: J
authors.lastname: Twardowska-Rajewska
authors.forename: Jan
authors.initials: J
authors.lastname: Gawecki
mesh_terms: D000483:Alleles; D001786:Blood Glucose / Q000032:analysis*; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage*; D005787:Gene Frequency; D005838:Genotype; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D050356:Lipid Metabolism / Q000187:drug effects*; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D011044:Poland; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D011795:Surveys and Questionnaires; D049629:Waist-Hip Ratio; D044465:White People
chemical_list: D001786:Blood Glucose; D006710:Homocysteine; D005492:Folic Acid; C573423:MTHFR protein, human; D042965:Methylenetetrahydrofolate Reductase (NADPH2)