title: Low levels of osteocalcin and leptin in serum of vegetarian prepubertal children.
abstract: BACKGROUND
  Scientific literature points to the positive association between vegetarian diet and reduced risk for cardiovascular diseases, some types of cancer and diabetes. On the other hand elimination of animal products from the diet decreases the intake of some essential nutrients which may influence bone metabolism. This is a very important problem especially in childhood and adolescence, when growth and bone turnover are the most intensive. Bone metabolism is regulated by variety factors, which are involved in the bone formation and bone resorption processes. Osteocalcin is one of the markers of bone formation (produced by osteoblast) which plays an important role in the regulation of bone growth. Recent data support the concept that other modulators such as leptin (hormone from adipose tissue) may influence bone formation process.
  
  
  OBJECTIVE
  Our study is designed to investigate serum concentration of osteocalcin and leptin in prepubertal children with two different nutritional habits: vegetarian and omnivorous diet.
  
  
  METHODS
  We examined 49 healthy children in age 2-10 years, who were divided into vegetarian and omnivores groups.
  
  
  RESULTS
  The serum osteocalcin levels in prepubertal children on vegetarian diet was significantly lower than in nonvegetarians (86.7+/-27.4 microg/L versus 100.1+/-16.4 microg/L; p<0.05). Lower level of osteocalcin is accompanied by lower leptin concentration. In children on vegetarian diet mean leptin level was 3.0+/-1.0 microg/L, whereas in omnivorous children it was 5.5+/-2.0 microg/L, (p<0.0001).
  
  
  CONCLUSIONS
  Our observation indicates that deficiencies in some of the nutrient components together with reduced serum concentration of leptin may retard relevant bone growth and development in childhood.
authors.affiliation: Zaklad Biochemii i Diagnostyki Laboratoryjnej, Instytut Matki i Dziecka, Kasprzaka 17a, 01-211 Warszawa, Poland. biochem@imid.med.pl
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Ambroszkiewicz
authors.forename: Teresa
authors.initials: T
authors.lastname: Laskowska-Klita
authors.forename: Witold
authors.initials: W
authors.lastname: Klemarczyk
mesh_terms: D002648:Child; D002675:Child, Preschool; D014676:Diet, Vegetarian; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood*; D008297:Male; D015675:Osteocalcin / Q000097:blood*
chemical_list: D020738:Leptin; D015675:Osteocalcin