[Conclusions and recommendations of a WHO expert consultation meeting on iron supplementation for infants and young children in malaria endemic areas]. / Conclusions et recommandations à l'issue de la consultation de l'OMS sur la lutte contre la carence martiale chez le nourrisson et le jeune enfant dans les pays d'endémie palustre.

This article presents the results of an expert consultation meeting aimed at evaluating the safety and public health implications of administering supplemental iron to infants and young children in malaria-endemic areas. Participants at this meeting that took place in Lyon, France on June 12-14, 2006 reached consensus on several important issues related to iron supplementation for infants and young children in malaria-endemic areas. The conclusions in this report apply specifically to regions where malaria is endemic.

The nutritional effects of tooth loss.

In view of the high prevalence of edentulousness in developed countries, the evidence is reviewed for the effects of tooth loss on nutrition and health in the following categories of effects: mortality; food choice and nutrient intake; gastrointestinal irritation; digestion and nutrient absorption; nutritional status. The evidence indicates reduced consumption of meat, fresh fruit, and vegetables, and total energy resulting in lower Hb and vitamin C levels, increased gastrointestinal irritation and increased mortality from choking but no striking differences in digestion or nutritional status. However, most studies are not carefully controlled for other social and health factors.

Effect of habitual exercise on daily energy expenditure and metabolic rate during standardized activity.

To assess whether long-term habitual exercise affects energy expenditure even on a nontraining day, 24-h energy expenditure (24-h EE) and metabolic rate of sedentary, moderately active, and highly active males (n = 10 per matched group), were measured in a room respirometer on two separate occasions: sedentary and standardized mild-exercise protocols. Twenty-four--hour EE was greatest in the highly active group, second highest in the moderately active group, and lowest in the sedentary group on both experimental days (sedentary day: 9908 +/- 344, 9328 +/- 357, and 8669 +/- 227 kJ/d; exercise day: 11915 +/- 395, 11609 +/- 328, and 11063 +/- 370 kJ/d, respectively). Differences were significant between the 24-h EE (P < 0.01), waking (P < 0.03), and sleeping metabolic rate (P < 0.01) of the highly active group compared with the sedentary group. However, when expressed per unit lean body mass (LBM), group values on both experimental days were not significantly different. Therefore, we found no evidence that habitual exercise, at a high or moderate level, leads to a significant prolonged stimulation of metabolic rate per unit active tissue. However, the increased LBM associated with exercise does increase daily energy expenditure by 8-14%.

The daily metabolic rate of the post-obese and the lean.

Daily metabolic rates of 16 post-obese women and 16 matched, lean controls were measured at three different levels of activity in a room respirometer. Both groups had similar height, weight, age, and other anthropometric indices. Results show that the post-obese have metabolic rates approximately 15% lower than their controls at any level of activity. They also eat less. Slimmed-down, obese women have a normal body composition. For both groups, aerobic exercise did not have a prolonged stimulatory effect on metabolic rate after the exercise had finished. Mild exercise was more effective than aerobic exercise in increasing daily metabolic rate because it could be comfortably sustained for a longer time. Implications of these findings are discussed in relation to the etiology and treatment of obesity.

Lactation and pregnancy in Iran. III. Hormonal factors.

Lactation failure is common in urban areas of industrially developing countries, but little is known about its epidemiology and causality. The study reported here was undertaken to investigate the serum levels of some hormones other than prolactin that have been shown in animal studies to play a role in lactation, and to examine their relationship to adequacy of lactation and to nutritional and socioeconomic status in urban Iranian women. Serum levels of placental lactogen, growth hormone, cortisol, and thyroid hormones were measured under standard conditions in two groups of pregnant women from low and low middle socioeconomic areas of Teheran, 1 or 2 weeks before parturition and the latter three hormones again in the 3rd month postpartum. Significant differences were found in the biochemical parameters between socioeconomic groups. Hemoglobin and serum albumin values were lower and all the globulin fractions (except alpha 2 globulin during pregnancy), growth hormone and cortisol were higher in the low than the middle socioeconomic subjects, both during pregnancy and postpartum. The discrepancies between the socioeconomic groups were greater postpartum. Growth hormone level was significantly lower in subjects with adequate lactation than inadequate or ceased, and cortisol values show the same trend. No correlations were found between the measured parameters of nutritional status nor free thyroxine values and lactation adequacy. In view of the role of growth hormone and cortisol in stress and malnutrition and some evidence of a reciprocal relationship between growth hormone and prolactin, these hormones may be a link in the chain between the urban environment, malnutrition and lactation failure.

Lactation and pregnancy in Iran. II. Diet and nutritional status.

Dietary intake in the third month postpartum and nutritional status during pregnancy close to term were assessed in Iranian urban uomen of low and middle socioeconomic status as part of a study investigating nutrition, hormonal status, and lactation in a population where lactation failure is a serious problem. Dietary intake was assessed by the 24-hr-recall method. The greatest differential in food groups consumed was in animal products, fruit, and vegetables. Intake of nutrients equal to or less than 80% of recommendations in both socioeconomic groups were energy, vitamin B6, folacin, calcium, iron, and zinc. In the low socio-economic group, only average intakes of vitamin C, thiamin and protein met the standards. Significant differences were found between the socioeconomic groups in hemoglobin, hematocrit, serum total protein, and protein fractions, but not in weight and height. The only parameters of nutritional status significantly correlated with adequacy of lactation were postpartum weight and percent of standard weight for height in the low socioeconomic group, and hematocrit values in the middle socioeconomic group. Differences between pregnant and postpartum individual values of the blood parameters were in general greater in the middle socioeconomic group than the low socioeconomic group.

PIP: Dietary intake in the 3rd month postpartum and nutritional status during pregnancy close to term were assessed in Iranian urban women of (LSE) low socioeconomic status and (MSE) middle socioeconomic status as part of a study investigating nutrition, hormonal status, and lactation in a population where lactation failure is a serious problem. Dietary intake was assessed by the 24-hour recall method. The greatest differential in food groups consumed was in animal products, fruit, and vegetables. Intake of nutrients = or than 80% of that recommended to both socioeconomic groups were energy, vitamin B6, folacin, calcium, iron, and zinc. In the LSE group, only average intakes of vitamin C, thiamin, and protein met the standards. Significant differences were found between the socioeconomic groups in hemoglobin, hematocrit, serum total protein, and protein fractions, but not in weight and height. The only parameters of nutritional status significantly correlated with adequacy of lactation were postpartum weight and % of standard weight for height in the LSE group, and hematocrit values in the MSE group. Differences between pregnant and postpartum individual values of the blood parameters were in general greater in the MSE group than the LSE group.

Lactation and pregnancy in Iran. I. Social and economic aspects.

Adequacy of lactation was assessed in Teheran women of low (LSE) and lower-middle (MSE) socioeconomic status in the third month postpartum, as part of a study linking nutrition, hormonal status, and lactation. Methods of assessment of nutritional adequacy are discussed. Characteristics of the socioeconomic groups, infant mortality, food beliefs related to lactation, and supplemental feeding practices are described. Of the LSE mothers 15 to 30% and of the MSE mothers 40 to 55% had a fully adequate milk supply in the third month. Substitutes used and affordable by the LSE were nutritionally inadequate. LSE mothers were traditional in their food beliefs. MSE mothers demonstrate the influence of scientific nutrition knowledge. The low percentage of lactation adequacy even in the MSE indicates that other social or health factors associated with urban living conditions may be just as important as economic and nutritional factors in lactation failure.

PIP: Adequacy of lactation was assessed in Teheran, Iran, among women of low (LSE) and lower-middle (MSE) socioeconomic status in the 3rd month postpartum as part of a study linking nutrition, hormonal status, and lactation. Subjects were selected randomly from women with uncomplicated pregnancies who attended 2 clinics in Teheran within 2 weeks of the expected date of birth. Subjects were interviewed, anthropometric data were obtained, and a blood sample was taken for hormonal and nutritional evaluation. Socioeconomic data, medical history, and dietary intake information were obtained. Characteristics of the socioeconomic groups, infant mortality, food beliefs related to lactation, and supplemental feeding practices are described. The criteria of lactation adequacy used were based primarily on the classification of nutritional status in early childhood as proposed by McLaren and Read. 15-30% of the LSE and 40-55% of the MSE mothers had a fully adequate milk supply in the 3rd month. Substitutes used and affordable by the LSE mothers were nutritionally inadequate, and this group of mothers was traditional in their food beliefs. MSE mothers demonstrated the influence of scientific knowledge. The low percentage of lactation adequacy even among the MSE mothers indicates that other social or health factors associated with urban living conditions may be as important as economic and nutritional factors in lactation failure.

Validation of a field technique for the measurement of energy expenditure: factorial method versus continuous respirometry.

The field technique for measuring daily energy expenditure, using activity diary plus short-term indirect calorimetry, was validated with a room respirometer. Eleven male and 14 female subjects spent 24-h periods in the respirometer and kept an activity diary to the nearest minute. Subsequently, the energy cost of the recorded activities was measured in duplicate, and 24-h expenditure was calculated. Over the 42 24-h measurements the mean value by the factorial field method was within 1% of that from continuous indirect calorimetry. However, the error in individual daily expenditure ranged from -17% to +25%. Correction of the error involved in using calculated BMR for the cost of sleeping resulted in a 5% mean underestimation of the daily value. The factorial method is, therefore, too inaccurate for the estimation of individual daily expenditures but provides a close estimate of the true energy expenditure for population groups.

A low-budget and easy-to-operate room respirometer for measuring daily energy expenditure in man.

Accurate assessment of energy requirements of humans under various physiological, pathological, and environmental conditions is hampered by the high cost of techniques for measuring daily energy expenditure. A room respirometer novel in its novel in its low cost of construction and simplicity of operation is described, together with an appreciation of errors and assumptions. It is suitable for measurements of daily energy expenditure in humans with an accuracy of +/- 1.5% and can be reproduced without difficulty in both developed and developing countries.

The energy expenditure of Iranian agricultural workers.

The energy cost of agricultural and standard activities and the daily energy expenditure of male agricultural workers were measured during different seasons in Iranian villages to assess the validity of past and present Food and Agricultural Organization recommended energy allowances for that population. Studies included low income farmers in a village representative of those around the central desert where harvesting takes place under conditions of extreme summer heat. Measurements were also made during the Moslem fasting period when no food may be eaten between dawn and dusk. Energy cost of typical activities was measured by indirect calorimetry using the Max-Planck respirometer and daily energy expenditure was assessed using these figures combined with a diary of activities throughout the 24-hr period. Results of individual activity values are compared with other published figures. Comparison of daily energy expenditure of fasting subjects and nonfasting after Ramazan showed no significant difference. No significant difference was found between values of standardized activities at high summer temperatures and moderate temperatures. Mean values of daily energy expenditure during winter when activity is low are around 2600 kcal/day and for the other seasons of high activity 3400 kcal/day. These figures suggest that past and present Food and Agricultural Organization standards are low for this population.

The energy expenditure of female carpet weavers and rural women in Iran.

The energy cost of individual activities and the daily energy expenditure of female carpet weavers and villagers were measured in Iranian villages and in the town of Isfahan as part of a series of studies to assess the validity for the population of past and present FAO recommended energy allowances. The energy cost of typical activities was measured by indirect calorimetry using Max-Planck respirometers. Daily energy expenditure was assessed using these figures combined with a 24-hr activity diary. The results of standard activity values are compared with other published values for Europeans and populations of countries with hot climates. The mean daily energy expenditure for both groups was in the order of 2000 kcal/day, below but close to the FAO recommendations which appear valid for rural women in a large part of the country but are probably an underestimate for areas where the participation of women in agriculture is greater.

Normal caffeine consumption: influence on thermogenesis and daily energy expenditure in lean and postobese human volunteers.

Single-dose oral administration of 100 mg caffeine increased the resting metabolic rate of both lean and postobese human volunteers by 3-4% (p less than 0.02) over 150 min and improved the defective diet-induced thermogenesis observed in the postobese subjects. Measurements of energy expenditure (EE) in a room respirometer indicate that repeated caffeine administration (100 mg) at 2-h intervals over a 12-h day period increased the EE of both subject groups by 8-11% (p less than 0.01) during that period but had no influence on the subsequent 12-h night EE. The net effect was a significant increase (p less than 0.02) in daily EE of 150 kcal in the lean volunteers and 79 kcal in the postobese subjects. Caffeine at commonly consumed doses can have a significant influence on energy balance and may promote thermogenesis in the treatment of obesity.

Antioxidant status and cancer mortality in China.

Sex-specific mortality rates for selected cancer sites (including oesophagus, stomach, liver, lung, colorectum, breast and cervix) and a variety of biochemical indicators of antioxidant status, enzyme activity and oxidative stress (including plasma levels of beta-carotene, alpha-tocopherol, ascorbic acid, selenium, glutathione peroxidase, catalase, superoxide dismutase, iron, copper, zinc, total cholesterol and lipid peroxide) were examined in an ecological study of 65 mostly rural counties in the People's Republic of China. The wide range of both mortality rates and biochemical values and the measurement of a comprehensive set of biochemical indicators permitted both simple correlational and multivariate analyses of the joint and relative effects of each factor on site-specific cancer mortality. Plasma levels of dietary antioxidants were consistently negatively correlated with cancer mortality rates. Ascorbic acid was most strongly negatively associated with most cancers and selenium with oesophageal and stomach cancers. beta-carotene was found to have a protective effect independent of retinol, particularly for stomach cancer.

The steady-state levels of oxidative DNA damage and of lipid peroxidation (F2-isoprostanes) are not correlated in healthy human subjects.

Oxidative damage to DNA in human tissues can be determined by measuring multiple products of oxidative damage to the purine and pyrimidine bases using gas chromatography-mass spectrometry (GC-MS). Oxidative damage to lipids (lipid peroxidation) can be quantitated by the mass spectrometry-based determination of F2-isoprostanes, specific end-products of the peroxidation of arachidonic acid residues in lipids. For both DNA base damage products and 8-epi prostaglandin F2alpha (PGF2alpha), there is a wide variation in levels between different healthy human subjects. We measured multiple products of oxidative damage to DNA bases in white cells, and 8-epi PGF2alpha in plasma, from blood samples obtained from healthy human subjects in the UK and in Portugal. No correlation of 8-epi PGF2alpha levels with levels of any modified DNA base (including 8-hydroxyguanine) was observed. We conclude that no single parameter can be measured as an index of "oxidative stress" or "oxidative damage" in vivo.

Lower metabolic rates of post-obese versus lean women: thermogenesis, basal metabolic rate and genetics.

Components of daily metabolic rate (thermogenesis, BMR and net exercise) were compared between 16 women predisposed to obesity (post-obese) and 16 naturally lean controls of matching age, weight and height, at three levels of activity, in a whole-body respirometer. At all levels of activity, the mean metabolic rate of the post-obese was 15 per cent lower than that of the lean controls. Expenditure on net exercise showed the same relationship, but BMR was only 10 per cent lower, while thermogenesis was 50 per cent lower. The latter was partly due to the smaller food intake of the post-obese and also to a lower thermogenic response. In absolute terms BMR accounted for less than half of the difference in total energy expenditure between the post-obese and the lean (45 per cent). Thermogenesis accounted for approximately 40 per cent of the difference, and 15 per cent after adjusting for the different energy intakes. Significantly more post-obese subjects had a family history of obesity (88 per cent) than lean subjects (38 per cent). Within the post-obese and lean groups there was a consistent trend at each level of activity for those with a family history to have lower metabolic rates, indicating that family history of obesity has an influence on energy expenditure over and above personal history of obesity.

Metabolic rate during and after aerobic exercise in post-obese and lean women.

The effect of aerobic exercise (cycling on bicycle ergometer for four 10-min periods/60-80 per cent max VO2) on energy expenditure following the activity was investigated in 16 post-obese and 16 lean control women over 24 h and shorter periods. In addition, net energy expenditure during aerobic exercise was compared to that during prolonged mild activity (stepping for four 30-min periods at 12 steps/min). The measurements were made in a room respirometer. Aerobic exercise did not significantly stimulate the 24-h resting metabolic rate of either the post-obese (3 per cent, 50 kcal) or lean controls (2 per cent, 30 kcal), nor was there any significant stimulation over shorter periods: during waking hours RMR was non-significantly increased by 5 per cent in both the post-obese and lean controls. Sleeping expenditure remained the same in the post-obese and was decreased by 2 per cent in the lean controls. All subjects found the aerobic exercise to be quite uncomfortable, yet in both groups the net cost was smaller than that of prolonged mild exercise which was found to be acceptable (post-obese: aerobic 180 kcal, mild 250 kcal; lean controls: 220 kcal, 290 kcal). It is suggested that prolonged mild activity (eg, as in walking frequently) is more appropriate in increasing energy expenditure as a means of preventing or controlling obesity. Total expenditure at each level of activity is also expressed as multiples of BMR calculated from FAO/WHO/UNU (1985) prediction equations and from measured sleep values. The results show that the equations overestimated BMR in the post-obese.

Impact of large-dose vitamin A supplementation on childhood diarrhoea, respiratory disease and growth.

One hundred and seventy-two 0.5-3.0-year-old children in a mountainous area of northern Hebei Province of China were randomly assigned to a vitamin A supplementation group (n = 98) or a control group (n = 74) for a 1 year double-blind study. Capsules containing 200,000 IU vitamin A and 40 IU vitamin E were given to the children in the experimental group 3 and 9 months after baseline examination. During the 12 month study period, there was a significant reduction in the incidence of diarrhoea (P < 0.01) and respiratory disease (P < 0.01) in the children of the experimental group compared to the control. Risk of diarrhoea and respiratory disease were respectively 2.5 and 3.4 times higher in the control children. Serum retinol and IgA levels of the treatment group were significantly higher than that of control group (P < 0.01) 7 weeks after first supplementation. There was no significant difference in saliva IgA level between groups. No significant differences in growth were observed. It was concluded that supplementation with large doses of vitamin A decreased the incidence and severity of diarrhoea and respiratory disease in these children, possibly through enhanced activity of the immune system, but had no effect on growth over 1 year.

Sources of energy from meals versus snacks in 220 people in four age groups.

OBJECTIVES: To assess meals versus snacks in terms of their contribution to total daily energy intake (TDI), macronutrient composition, and food commodity profile. DESIGN AND SUBJECTS: Meals and snacks were assessed from 220 7-day weighed dietary records. 187 records were obtained from three separate existing studies, and reanalysed. These studies contained data on three different age groups in the British population; elderly group (n = 88), middle-aged group (n = 40), young adult group (n = 59). A separate study of 13-14-year-olds living in Croydon was conducted from which 33 usable diet records were collected (adolescent group). RESULTS: Boys in the adolescent group consumed more of their TDI as snacks (29.0%) compared with men in the young adult (18.9%) and elderly groups (16.6%), but not the middle-aged group (25.8%). Females consumed about the same percentage of their TDI as snacks; adolescent group 23.6%, young adult group 19.4%, middle-aged group 21.4%, elderly group 17.9%. Meals were higher in protein and fat, and lower in total sugars, compared with snacks. Chocolate confectionery, crisps and fizzy drinks and squashes were popular snack foods in the adolescent group. Unlike snacks, the food commodity profiles of meals were similar in all age groups. CONCLUSIONS: This study shows that foods and drinks consumed as snacks by the British public, including the elderly, have a relatively high total sugar composition. These results add to the concern relating snack foods with dental caries.

Relationship between feeding pattern and body mass index in 220 free-living people in four age groups.

OBJECTIVE: To assess the relationship between feeding pattern and body mass index in free-living humans. DESIGN AND SUBJECTS: Feeding pattern was assessed from 220 7-day weighed dietary records. 187 records were obtained from three separate existing studies, and reanalysed. These studies contained data on three age groups in the British population; Elderly group (n = 88), Middle-aged group (n = 40), Working age group (n = 59). A separate study of 13-14 year olds living in Croydon was conducted from which 33 usable diet records were collected to produce a fourth, Adolescent group. RESULTS: 'Nibbling' and greater energy intakes at breakfast were associated with a lower body mass index (BMI) in the Adolescent group. In the Middle-aged group, greater energy intakes at breakfast and lower energy intakes during the evening were associated with a lower BMI. However, when diet records which produced unreasonably low energy intakes were removed from the analysis, these relationships disappeared except for energy intakes at breakfast and BMI in the Adolescent group. CONCLUSION: It is suggested that the relationship between feeding pattern and BMI observed in the Adolescent and Middle-aged groups was caused by underestimation of 'habitual' energy intake from snacks and the omission of breakfast by females and those who were overweight. The lack of relationship in the Working age group was attributed to the fact that more individuals in this group appeared to report valid diet records. Reported energy intake was directly related to BMI in the Working age group, but was not related to BMI in the other three age groups. It is concluded that feeding pattern is not a major factor in determining BMI in humans. Also, since snacks have a relatively high sugar and low fat composition compared with meals, it is suggested that biased under-reporting of snacks by the obese could produce spurious results from free-living studies which show that obesity is related to the proportion of energy from fat in the diet.

Transcranial Doppler monitoring during induction of anesthesia: effects of propofol, thiopental, and hyperventilation in patients with large malignant brain tumors.

Disturbed autoregulation and CO2 reactivity have been reported in patients with brain tumors. Therefore, we decided to monitor the cerebrovascular effects of anesthetic drugs and hyperventilation. Transcranial Doppler sonography (TCD) can measure noninvasively alterations of flow velocities (v) and cross-sectional vessel area (VA) in large brain arteries. Twenty-eight patients with large malignant brain tumors in the territory of the middle cerebral artery (MCA) randomly received propofol or thiopental for induction and maintenance of anesthesia. Mean arterial pressure (MAP), heart rate (HR), and TCD parameters (vMCA and VA of the tumor or nontumor side) were determined at six data points (DP). The first measurements (MAP, HR, and TCD of the nontumor side) were performed before (DP I) and 60 s after (DP II) induction of anesthesia with either 2 mg/kg propofol or 4 mg/kg thiopental. After intubation and normoventilation (50% O2 in air), 0.05-0.1 mg/kg midazolam and an alfentanil infusion (100 micrograms/kg x h) were initiated. Then MAP, HR, vMCA, and VA of the tumor side were analyzed before (DP III) and 60 s after (DP IV) either propofol (1 mg/kg) or thiopental (2 mg/kg) were given. Finally, the effects of hyperventilation on HR, MAP, vMCA, and VA (tumor side) were determined (DP V and VI). Mean +/- SD, thiopental or propofol reactivity (non-tumor and tumor side) and CO2 reactivity (tumor side) were calculated; statistical comparison between DP I and II, III and IV, and V and VI was performed by paired t tests (p < 0.05). Unpaired t tests were used to evaluate differences between groups.(ABSTRACT TRUNCATED AT 250 WORDS)