Recovery of initial body weight and composition after long-term massive overfeeding in men.

To verify the existence of a set point for body mass, the spontaneous evolution of body weight and composition after massive overfeeding was observed in nine lean young Cameroonian (Massa) men participating in a 4-6 mo traditional fattening session (Guru). Anthropometry (skinfold thicknesses) was used to estimate body composition. Peak weight and fat gains were found to be 19 +/- 3.2 (mean +/- SD) kg and 11.8 +/- 2.5 kg, respectively. Two and one-half years after cessation of fattening and a return to daily life and food habits, there was a spontaneous return to initial body weight and body composition of the overfed subjects. Because the subjects were not under social or other stimuli to lose weight, this finding argues in favor of the existence of a biological control of energy balance at a "preferred" level in nonobese individuals.

Massive overfeeding and energy balance in men: the Guru Walla model.

To determine the magnitude of the thermogenic response to a massive long-term overfeeding, an energy-balance study was carried out in nine lean, young Cameroonian men participating in a traditional fattening session: the Guru Walla. Food intake, body weight, body composition, activity, and metabolic rates were recorded during a 10-d baseline period and over the 61-65 d of fattening. Total energy expenditure (TEE) was measured by using doubly labeled water during the baseline period and the final 10 d of Guru Walla. Cumulative overfeeding consisted of 955 +/- 252 MJ (chi +/- SD) mainly as carbohydrate. Body-weight increase was 17 +/- 4 kg, 64-75% as fat. Metabolic rates increased but TEE did not. However, when accounting for the reduction in physical activity, substantial thermogenesis was observed but its amplitude was not greater than that observed under less extreme carbohydrate-overfeeding conditions. If luxuskonsumption does exist, it is not related to the magnitude of the cumulative overfeeding.

Social valorisation of stoutness as a determinant of obesity in the context of nutritional transition in Cameroon: the Bamiléké case.

Body size perceptions were assessed among members of the Bamiléké, an ethnic group in an urban setting in Cameroon with high rates of obesity, but also a positive perception of stoutness in its social representations. We first implemented a qualitative study (April 2007) to identify local representations of body weight among Bamiléké using semi-structured interviews. We then quantitatively assessed body size perceptions among a representative sample of Bamiléké (May to June 2007), employing a body image assessment scale and a questionnaire that included declarative body weight self-satisfaction, health status, and attempts to reduce weight. Results indicate Desired Body Size (DBS) for women, and particularly for men, was situated in the overweight category. Qualitative analyses show that overweight is considered as a normal and healthy body size in the Bamiléké. On the other hand, the quantitative study reveals that high rates of obesity, especially in women (40.8% obese), are associated with high blood pressure. Moreover, subjects who had a negative perception of their health status wanted to lose weight (p < 0.01). Unlike males, females have a DBS lower than their Current Body Size (p < 0.001). In addition, subjects (particularly males) who felt they were too lean, were older than those who felt too fat. We therefore conclude that the social valorisation of stoutness exposes Bamiléké, particularly males, to obesity. Although the women stated a desire to lose weight and present aesthetic criteria more oriented towards slimness, the attitude of the Bamiléké remained oriented toward stoutness appreciation. This preference can help protect against body image disturbances identified in Western societies, but may also increase of the incidence of obesity and its associated pathologies in this part of the world.

[Evolution of age at menarche in France]. / Evolution de l'age d'apparition des premieres regles (menarche) in France

PIP: The authors examine data on age at menarche among a sample of 3,355 female students aged 17-21 who were born in France. The mean age at menarche is calculated, and comparisons are made with data for 1841 and other years. The decline in age at menarche over time is considered, and trends in other countries are also discussed^ieng

Cognitive factors in the dietary response of restrained and unrestrained eaters to manipulation of the fat content of a dish.

This study examined the dietary intake and rated internal state of 16 normal-weight young women following the manipulation of the actual or the presented fat and energy content of a test dish eaten at lunch. Half of the subjects were classified as restrained and half as unrestrained eaters. The test dish was either 2473 kJ (591 kcal) in its high-fat version or 1485 kJ (355 kcal) in its low-fat version, and was provided either with a correct or incorrect information about its fat content. All the intakes at the three meals during the following 8 h were covertly recorded in the laboratory, and internal state rated on four occasions. After the low-fat test dish presented as low-fat, unrestrained eaters increased their energy intake compared to that in other conditions. Restrained subjects did not exhibit this pattern and compensated for the missing energy in the low-fat test dish, compared to the high-fat test dish, only when they were informed that both dishes were high in fat. Irrespective of the information, both restrained and unrestrained subjects reported weaker sensations of hunger after the actual high-fat test dish than after the actual low-fat test dish whereas only restrained eaters reported stronger sensations of fullness. Thus, the influence of the cognitive factors on food intake and ratings of internal state is modulated by restrained eating behaviour.

[Comparison of serum levels of beta2-microglobulin and carcino-embryonic antigen in the follow-up of lung cancer (author's transl)]. / Comparaison des taux sériques de la beta2-microglobuline et de l'antigène carcino-embryonnaire dans la surveillance du cancer broncho-pulmonaire.

Serum levels of carcino-embryonic antigen (CEA) and beta2-microglobulin (beta2m) were assayed on 133 sera during follow-up of 31 patients with lung carcinoma (squamous cell ca. without recurrence : 2, squamous cell ca. with recurrence : 11, anaplastic cell ca. : 4, adenocarcinoma : 2, unclassifiable : 5). Normal creatinine (less than or equal to 12 mg/l) levels were found in all sera. CEA and beta2m levels showed no correlation nor in these groups, nor in the whole. The squamous cell carcinomas with recurrence showed the largest dispersion for CEA as for beta2m levels. However, the trends of serial beta2m values did not correlate with clinical features. Increasing or decreasing levels of CEA and beta2m levels showed no correlation in the whole nor in patients undergoing radiotherapy. In our experience, beta2m levels failed to correlate with clinical findings during the follow-up of lung cancer patients.

New perspectives on taste and primate evolution: the dichotomy in gustatory coding for perception of beneficent versus noxious substances as supported by correlations among human thresholds.

In various environments where primates are presently observed, as well as in forests and savannas which have been inhabited by australopithecines and early hominids, there are (or there have been presumably) categories of substances eliciting taste signals associated with stereotyped responses. Such is the case for various soluble sugars of fruits and nectars, attracting consumers, and for several plant compounds in which bitter or strongly astringent properties have a repulsive effect. The occurrence of such classes of tasty substances among natural products appears to be related to the evolutionary trends that shaped primate sensory perception (for detecting either beneficent or potentially noxious substances) in the context of a long history of coevolution between animals and plants. Here, we present original psychophysical data on humans (412 individuals aged 17-59 years) as an analogy with which to test recent evidence from electrophysiology in nonhuman primates (Hellekant et al. [1997] J. Neurophysiol. 77:978-993; Danilova et al. [1998] Ann. N.Y. Acad. Sci. 855:160-164) that taste fibers can be grouped into clusters of "best-responding fibers" with two more specific clusters, one for sugars and one for quinine and tannins. The collinearity found between human taste responses (recognition thresholds) for fructose and sucrose, as well as for quinine and tannins, is presented and discussed as another evidence of the two-direction evolutionary trend determining taste sensitivity. Salt perception appears to be totally independent of these trends. Accordingly, the appreciation of a salty taste seems to be a recent culturally learned response, and not a primary taste perception. The very existence of primary tastes is discussed in the context of evolutionary trends, past and present.

Effect of a covert fat dilution on the spontaneous food intake by lean and obese subjects.

Nine lean and nine obese subjects participated in two laboratory studies comparing the effects of a traditional high-fat dish (2.42 MJ and 49% as fat) and its convert fat-reduced version (1.53 MJ and 23% as fat) on subsequent food intake. Each version was consumed at the beginning of a free-choice lunch (experiment 1) or alone at lunch time (experiment 2). All subjects experienced both experiments. Three and 7 h after lunch, subjects were free to consume any of the items available in a vending machine. Food intake was measured directly. In experiment 1, by 8 h after lunch, mean cumulative energy intake (test dish included) was not different between the test dish conditions in both lean and obese subjects, and ad libitum energy intake (i.e. without test dish) was significantly higher under the low-fat than under the high-fat test dish condition. Thus, lean compensated 86% and obese 70% of the initial energy reduction. The cumulative fat intake (test dish included) was lower under the low-fat than under the high-fat dish condition for both weight groups. Nevertheless, the percentage of ad libitum energy intake derived from fat was significantly higher after the low-fat test dish in obese but not in lean subjects. In experiment 2, both weight groups maintained the energy and fat reduction. Thus, obese subjects did not respond differently to lean subjects to the fat and energy manipulation of the test dish, except for the percentage of fat in their diet. These results suggest that different ways of including fat-reduced foods into the habitual diet might have different effects on subsequent energy compensation.

Prevalence of overweight and obesity for urban adults in Cameroon.

BACKGROUND: The emergence of a nutrition transition in developing countries might lead to higher prevalence of obesity and related adverse health effects. In Cameroon,urbanization growth rate is one of the highest in sub-Saharan Africa. Such dramatic demographic change favours important modifications, notably in nutritional patterns. AIM: In this paper we examine the current prevalence of overweight and obesity in Yaounde,the capital city of Cameroon and search for possible causal factors. Detrimental consequences of overweight are also discussed. MATERIAL AND METHODS: Samples of adults (519 women, 252 men) of all ages in all districts of Yaounde were subjected to anthropometric and body composition measurements, blood pressure and resting heart rate determination, and interviewer-administered questionnaires on socio-demography, smoking habits, physical activity, self-perception of body weight and health status. RESULTS: In both sexes body mass index (BMI) increases with age and peaks in the years of maturity. These changes are related to changes in adiposity. Prevalence rates of overweight(BMI >or= 25) and obesity (BMI > or = 30) increase from 20 to 29 years and peak at 40-49 years in men and at 50-59 years in women before starting to decline. One woman in two is overweight and one woman in five is obese, whereas one-third of men are overweight and only 5% are obese. Obese subjects have a larger age-adjusted waist to hip ratio(WHR) than their non-overweight counterparts, attesting that fat gain is oriented towards a more abdominal fat mass distribution. The length of residence in Yaounde, increasing education level, occupation, ethnicity, physical inactivity and smoking practices appear to influence early overweight and/or obesity. No parity effect is observed in women. From the present study, it appears that obesity, and especially obesity in women, could be less benign than that described in other studies in Africa. CONCLUSION: Research is needed in Cameroon, including aetiological and cohort studies aimed at the quantification of morbidity and mortality risks associated with overweight and obesity.

Relationships between threshold-based PROP sensitivity and food preferences of Tunisians.

The extent to which taste responses--and notably the genetically determined sensitivity to 6-n-propylthiouracil (PROP)--influences food preferences and food use is still a matter of debate. We addressed the issue on the basis of a behavioural and anthropological study performed in Tunis in 1999. The working sample consists of 123 adults of both sexes (38 men, 85 women), aged 19-59, in various social categories. Taste recognition thresholds for sucrose, fructose, sodium chloride, quinine hydrochloride, citric acid, tannic acid, oak tannin and PROP were determined by presenting, in a semi-randomised order (blind-test), series of graded aqueous solutions of each product. Subjects also tasted and rated the pleasantness/unpleasantness of 4 supra-threshold solutions of NaCl and sucrose. All subjects completed a checklist of 43 food items representative of Tunisian diet, rated in terms of flavour, cost, effect on health and prestige on a labelled affective magnitude scale. According to the underlying distribution of PROP thresholds, the subjects were separated into three categories: "non-tasters", "medium-threshold tasters", and "low-threshold tasters". Results bring out the specificity of low-threshold tasters, as exhibiting a greater taste sensitivity for most tested substances. Low-threshold taster status is also linked to higher mean food preferences ratings irrespective of sex, age and socio-cultural influences. Tasters as a group (medium-threshold tasters + low-threshold tasters) do not exhibit a higher percentage of food dislikes; however PROP sensitivity is negatively correlated with hedonic responses to NaCl solutions. These results together with the evidence of a limited set of food actually used by low-threshold tasters suggest that these subjects might have difficulties at overcoming an inherent neophobia.

Age at menarche and urbanization in Cameroon: current status and secular trends.

Status quo data on the age at menarche were obtained on samples of Cameroonian girls living in urban (Yaoundé) (n = 205), suburban (n = 505) and rural areas (n = 201). Mean ages at menarche, estimated by probit analysis, are 13.18 years (SD 1.08) in Yaoundé, 13.98 years (SD 1.55) in the suburban area, and 14.27 years (SD 1.65) in the rural area. The early menarcheal age observed in Yaoundé girls attending 'privileged schools' (12.72 years, SD 1.18) substantiates the hypothesis that in good environmental conditions Africans are as early-maturing as Asiatic or Mediterranean populations. Comparison with retrospective data on age at menarche during previous decades reveals the presence of a clear secular trend towards earlier maturation, at a rate of 2.5-3.2 months per decade, only in the main cities of the country (Yaoundé/Douala) and a lack of temporal variation in rural areas. The degree of urbanization influences maturational age and its evolution, probably through improvements in the nutritional standards.

PIP: "Status quo data on the age at menarche were obtained on samples of Cameroonian girls living in urban (Yaounde) (n=205), suburban (n=505) and rural areas (n=201).... Comparison with retrospective data on age at menarche during previous decades reveals the presence of a clear secular trend towards earlier maturation, at a rate of 2.5-3.2 months per decade, only in the main cities of the country (Yaounde/Douala) and a lack of temporal variation in rural areas. The degree of urbanization influences maturational age and its evolution, probably through improvements in the nutritional standards." (EXCERPT)