title: Vegetarianism produces subclinical malnutrition, hyperhomocysteinemia and atherogenesis.
abstract: OBJECTIVE
  To explain why vegetarian subjects develop morbidity and mortality from cardiovascular diseases unrelated to vitamin B status and Framingham criteria.
  
  
  METHODS
  A study of 24 rural male subjects 18 to 30 y old and 15 urban male controls was conducted in the Sahel region of Chad. Food consumption was determined from a dietary questionnaire, and overall health status was assessed by body weight, body mass index, serum albumin, plasma transthyretin, urinary nitrogen, and creatinine. Plasma lipids, vitamins B6, B9 and B12, homocysteine, and related sulfur amino acids were measured as selected cardiovascular disease risk factors.
  
  
  RESULTS
  Body weight, body mass index, blood, and urinary markers of protein status were significantly lower, with an estimated 10% decrease of lean body mass in the study group compared with urban controls. Neither lipid fractions nor plasma levels of vitamins B6, B9, and B12 were significantly different between the two groups. Although the mean consumption of sulfur amino acids (10.4 mg·kg(-1)·d(-1)) by rural subjects was significantly below the recommended dietary allowances (13 mg·kg(-1)·d(-1)), plasma methionine values were similar in the two groups. In contrast, homocysteine concentration was significantly increased (18.6 μmol/L, P < 0.001), and the levels of cysteine and glutathione were significantly decreased in the study group, demonstrating inhibition of the trans-sulfuration pathway. The strong negative correlation (r = -0.71) between transthyretin and homocysteine implicated lean body mass as a critical determinant of hyperhomocysteinemia.
  
  
  CONCLUSIONS
  The low dietary intake of protein and sulfur amino acids by a plant-eating population leads to subclinical protein malnutrition, explaining the origin of hyperhomocysteinemia and the increased vulnerability of these vegetarian subjects to cardiovascular diseases.
authors.affiliation: Laboratory of Nutrition, Faculty of Pharmacy, University Louis Pasteur, Strasbourg, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Ingenbleek
authors.forename: Kilmer S
authors.initials: KS
authors.lastname: McCully
mesh_terms: D000293:Adolescent; D000328:Adult; D000596:Amino Acids / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism; D050197:Atherosclerosis / Q000097:blood / Q000209:etiology* / Q000652:urine; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001823:Body Composition; D015992:Body Mass Index; D001835:Body Weight; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology / Q000652:urine; D002596:Chad; D004034:Diet Surveys; D014676:Diet, Vegetarian / Q000009:adverse effects*; D004044:Dietary Proteins / Q000008:administration & dosage / Q000378:metabolism; D006304:Health Status; D006801:Humans; D020138:Hyperhomocysteinemia / Q000097:blood / Q000209:etiology* / Q000652:urine; D008297:Male; D018673:Nutrition Policy; D009752:Nutritional Status; D011488:Protein Deficiency / Q000097:blood / Q000150:complications* / Q000652:urine; D012307:Risk Factors; D012424:Rural Population; D013455:Sulfur / Q000008:administration & dosage; D011795:Surveys and Questionnaires; D014803:Vitamin B Complex / Q000097:blood; D055815:Young Adult
chemical_list: D000596:Amino Acids; D015415:Biomarkers; D004044:Dietary Proteins; D014803:Vitamin B Complex; D013455:Sulfur