Body composition: an important determinant of homocysteine and methionine concentrations in healthy individuals.
OBJECTIVE
Homocysteine is a sex-related risk factor for cardiovascular disease but the reason for dimorphism is unclear. It has been hypothesized that fat-free mass is an independent determinant of the circulating homocysteine and methionine concentrations.


METHODS
The relationship of homocysteine to body composition was investigated in 52 healthy middle-aged 40-60 year olds. Plasma total homocysteine, methionine, folates, vitamins B6 and B12 concentrations were measured with fat mass, bone mineral content, lean body mass, fat-free mass, body water compartments and resting energy expenditure by Anthropometry, Dual X-ray Absorptiometry, Bioimpedentiometry and Indirect Calorimetry.


RESULTS
Men had higher homocysteine (+28%) and methionine (+18%) concentrations than women, but a similar ratio between the two concentrations. Men also had higher lean body mass and fat-free mass. Homocysteine and methionine concentrations were significantly related to fat-free mass, lean body mass, total, extracellular and intracellular water both in simple correlations and in multivariate models including age, smoking habits and vitamin concentrations. Fat-free mass related measures explained the sex effect on homocysteine and methionine concentrations but not the ratio of homocysteine to methionine concentrations.


CONCLUSIONS
In healthy middle-aged adults homocysteine concentration independently relates to fat-free mass and to water components. Homocysteine and methionine concentrations increase together in relation to the proportion of fat-free mass but their ratio is unrelated to fat-free mass.
Battezzati
Alberto
A
Nutrition Section, Dipartimento di Scienze e Tecnologie Alimentari e Microbiologiche, International Center for the Assessment of Body Composition, Università degli Studi di Milano, Milano, Italy. alberto.battezzati@unimi.it <alberto.battezzati@unimi.it>
Bertoli
Simona
S
San Romerio
Antonella
A
Testolin
Giulio
G
D000273:Adipose Tissue / Q000378:metabolism / Q000502:physiology; D000328:Adult; D001823:Body Composition / Q000502:physiology*; D001834:Body Water / Q000378:metabolism / Q000502:physiology; D005260:Female; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000097:blood; D008019:Life Style; D008297:Male; D008593:Menopause / Q000097:blood; D008715:Methionine / Q000097:blood*; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology*; D012307:Risk Factors; D012737:Sex Factors; D014805:Vitamin B 12 / Q000097:blood; D025101:Vitamin B 6 / Q000097:blood; D014803:Vitamin B Complex / Q000097:blood*
D006710:Homocysteine; D014803:Vitamin B Complex; D025101:Vitamin B 6; D005492:Folic Acid; D008715:Methionine; D014805:Vitamin B 12