Serum concentration of biochemical bone turnover markers in vegetarian children.

PURPOSE: In general, most children on well-planed vegetarian diets can achieve normal growth and development. However, elimination of animal products from the diet decreases the intake of some essential nutrients, such as calcium and vitamin D, and may influence bone metabolism. This is especially important in childhood and adolescence, when growth and bone turnover are most intensive. The aim of this study was to investigate the serum concentrations of biochemical bone turnover markers in prepubertal vegetarian children. MATERIAL AND METHODS: We examined 50 children on vegetarian and 50 on omnivorous diets aged 2-10 years. Dietary constituents were analyzed using a local nutritional program. Serum bone formation (OC, BALP) and resorption (CTX) markers were determined by specific enzyme immunoassays (ELISA) and 25-hydroxyvitamin D by the chemiluminescence method (CLIA). RESULTS: The average daily energetic value and the percentage of energy from protein, fat and carbohydrates in the diets were similar in both groups of children and were within the recommended range. The vegetarian children showed about a two-fold lower daily intake of calcium and vitamin D than their omnivorous counterparts. The level of 25-hydroxyvitamin D in the serum of vegetarian children was also nearly 2-fold lower compared with omnivores. In vegetarians, as compared to non-vegetarians, mean serum concentrations of OC, BALP and CTX were lower by about 20%, 10% and 15%, respectively. CONCLUSION: Our preliminary results suggest that an inadequate dietary intake of calcium and vitamin D may impair bone turnover rate in vegetarian children. The parameters of bone metabolism should be monitored in these children in order to prevent bone abnormalities.

Serum homocysteine, folate, vitamin B12 and total antioxidant status in vegetarian children.

PURPOSE: The results of several studies point to the positive role of vegetarian diets in reducing the risk of diabetes, some cancers and cardiovascular diseases. However, exclusion of animal products in vegetarian diets may affect the cobalamin status and cause an elevation of the plasma homocysteine level. The aim of this study was to assess the effect of vegetarian diets on serum concentrations of homocysteine, folate, vitamin B12 and total antioxidant status (TAS) in children. MATERIAL AND METHODS: The study included 32 vegetarians (including 5 vegans), age 2-10 years. Dietary constituents were analyzed using a local nutritional programme. Serum homocysteine, folate and vitamin B12 were determined with fluorescence and chemiluminescence immunoassays. The concentration of TAS was measured by a colorimetric method. RESULTS: Average daily energy intake and the percentage of energy from protein, fat and carbohydrates in the diets of the studied children were just above or similar to the recommended amounts. It could be shown that vegetarian diets contain high concentrations of folate. In vegan diets it even exceeds the recommended dietary allowance. Mean daily intake of vitamin B12 in the studied diets was adequate but in vegans was below the recommended range. The serum concentrations of homocysteine, folate, vitamin B12 and TAS in vegetarian children remained within the physiological range. CONCLUSIONS: The presented data indicate that vegetarian children, contrary to adults, have enough vitamin B12 in their diet (excluding vegans) and normal serum concentrations of homocysteine, folate and vitamin B12. Therefore, in order to prevent deficiencies in the future, close monitoring of vegetarian children (especially on a vegan diet) is important to make sure that they receive adequate quantities of nutrients needed for healthy growth.

Low serum leptin concentration in vegetarian prepubertal children.

PURPOSE: Vegetarian diet may play a positive role in reducing risk of several chronic diseases such as diabetes, coronary heart disease and some types of cancer. There are different vegetarian dietary patterns, some of which are nutritionally adequate for children, whereas other may lack some essential nutrients. Leptin, a hormone from adipose tissue plays a key role in the control of body fat stores and energy expenditure. Higher leptin levels were observed in obese subjects and lower in anorectic patients. Recent studies support that diet may be a factor which influences leptin levels. The aim of this study was to investigate serum concentrations of leptin, lipids and apolipoproteins in prepubertal children with two different nutritional habits: vegetarian and omnivorous diet. MATERIAL AND METHODS: We examined 22 vegetarians and 13 omnivores in age 2-10 years. Serum leptin concentration was determined by immunoenzyme assay (ELISA) and serum lipids were measured by enzymatic and immunoturbidimetric methods. RESULTS: Average daily dietary energy intake and the percentage of energy from protein, fat and carbohydrates were similar for both groups of children. We observed that in vegetarian diet there is a high rate of fiber nearly twice as high as in omnivorous diet. Vegetarians had lower total cholesterol and HDL- and LDL-cholesterol concentrations than children on traditional mixed diet. There is no significant differences in triglyceride concentration between studied groups. The apolipoproteins levels in vegetarian children were significantly below that of omnivores. The serum concentration of leptin was lower in vegetarians (3.0 +/- 1.1 ng/mL) than in nonvegetarians (5.1 +/- 2.0 ng/mL) (p < 0.01). CONCLUSIONS: Our results suggest that vegetarian diet may be accompanied by lower serum leptin concentration. Further studies on large group of children are needed for understanding this problem better.

[Serum leptin level in prepubertal children with simple obesity. Part one]. / Ocena poziomu leptyny u dzieci w wieku przedpokwitaniowym z otyloscia prosta. Czesc I.

The aim of the study was to determine the serum leptin level and anthropometric indices (body mass index - BMI) in a group of prepubertal children with simple obesity. These parameters were compared with the values characteristic for the group of slim children. The study showed that serum leptin levels were significantly higher in obese children compared with the group of slim children (p<0.0001). There was a positive correlation (r=0.48; p<0.05) between leptin levels and nutritional status indices expressed by BMI. Results of this study suggest that leptin level in the group of children with simple obesity does not have an effect on satiety, on reduction of appetite or on the increment of adipose tissue. The study showed also that hyperleptinemia might be an effect of leptin resistance.

[Nutrition of preschool age children. General considerations and assessment of child nutrition]. / Zywienie dzieci w wieku przedszkolnym. Ogólna charakterystyka sposobu zywienia.

Results of the study performed between June 1999 and January 2000 on dietary assessment of 822 pre-school children (age 3-7) showed that majority of children regularly consumed the main meals: breakfast, dinner and supper. The habit of snacks eating between the meals was observed in 91% of children. The presence and structure basic products in analysed children diets (milk, fermented milk products, fats, fish, whole grain bread, juices) was different. About 87% reported drinking of milk, 75%--yoghurt or other fermented milk products, 97%--fruit juices including nectar, water--42%. The main fat used to spreading on bread was butter. Fish products recommended as a source of n-3 polyunsaturated fatty acids were still not eaten by 23% of children. Whole grain bread was consumed daily only in 8% children. The study also showed that the diets included products being the source of unfavourable fatty acids (chips, sweet bars, cookies, hard margarine) and excess of saccharose (sweets, lollipops, chewing gum). The results of the study showed the permanent need of the dissemination of dietary recommendations for children at pre-school age.

[Evaluation of a diet and nutritional status of breast feeding women on the basis of a questionnaire study]. / Ocena sposobu zywienia i stanu odzywienia kobiet karmiacych piersia na podstawie badania ankietowego.

The subjects were 120 breast-feeding mothers whose children were admitted for outpatient or inpatient treatment at the Institute of Mother and Child in Warsaw, between March, 1998 and July, 1999. A special nutritional questionnaire was elaborated with the aim to evaluate subjects' nutritional status as well as their diet. All subjects completed the questionnaire and then selected parameters of their nutritional status and diet were evaluated. For 43 of the women under study it was the first month of lactation, for 33--the fourth month, for 23--the sixth and 21 women had been breast-feeding for more then six months. The subjects were of different age, coming from both urban and rural areas. In the studied group the nutritional status, i.e. body mass indices (BMI) before pregnancy, at the end of pregnancy and during lactation were within the normal range. 65 of the subjects had changed their diet due to pregnancy and 52 due to lactation. Women declared to be used to eating 3-4 meals per day. Having additional snacks was declared by 62.5%. Liquids' intake was on average about 2.5 l/24 hr, range 2-31. Average daily energy intake--2938 kcal/12,980 kJ, the lowest--in a diet of a mother with diabetes, the highest--in a diet of a vegetarian mother. The proportion of protein in energy intake was 15.1%, whereas fat--36.3%. Dietary practices of women under study in the period of lactation were well adjusted to nutritional recommendations for this group, as evidenced by indices of nutritional status (i.e. BMI). Among 120 women, 71 were taking supplementary preparations of vitamins and minerals. It turned out that a level of some vitamins in a daily food intake together with supplementation was definitely too high.