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Objective: The relative influence of dietary factors vs physical activity on cardiovascular risk factors are poorly understood. We investigated these factors in a population whose traditional diet may have both positive (high plant-based) and negative (high refined carbohydrate) aspects, and whose physical activity levels (PALs) vary widely., Design: Cross-sectional study., Subjects: A total of 130 weight stable adults aged 35-49 y (BMI 18-35 kg/m(2)) living in urban Beijing, China., Measurements: Dietary intake (by food frequency questionnaire), PAL as the ratio of predicted total to resting energy expenditure), percent body fat (by deuterium oxide dilution), and central adiposity (waist circumference and waist to hip ratio) were assessed. Biochemical parameters (total cholesterol, low- and high-density lipoprotein cholesterol (LDL-C; HDL-C), triglyceride (TG), apolipoproteins A-I and B, glucose, insulin, and homocysteine and its related vitamins), blood pressure and presence of the metabolic syndrome (having >/=3 risk factors of central adiposity, HDL-C, TG, glucose, blood pressure) were also examined., Results: Mean values for cardiovascular risk factors were relatively low, but 19% of subjects had the metabolic syndrome. Using validated methods for measuring food intake and energy expenditure, we found that an adverse cardiovascular risk profile was associated with a diet high in carbohydrate, low in polyunsaturated fat, and low in fruit and vegetables, independent of body fatness and its distribution. While dietary factors predicted individual cardiovascular risk factors more consistently than PAL, avoidance of low PAL reduced the risk of having the metabolic syndrome., Conclusion: These results suggest that, regardless of total body fatness and fat distribution, multiple unfavorable dietary factors and low physical activity independently increase the risk for cardiovascular disease. Avoidance of a sedentary lifestyle additionally reduces the risk of developing the metabolic syndrome.

Background: Factors affecting the accuracy of reported energy intake (rEI) need to be identified., Objective: Our objective was to investigate the association of psychological measures of eating behavior with the accuracy of rEI assessed by 7-d weighed intakes, a 24-h recall, and a food-frequency questionnaire., Design: Subjects were 26 restrained eaters aged 60.3 +/- 0.6 y (mean +/- SEM) and weighing 63.8 +/- 1.7 kg and 34 unrestrained eaters aged 59.4 +/- 0.6 y and weighing 64.0 kg. rEI was assessed by using 3 dietary assessment methods and total energy expenditure (TEE) was determined by using doubly labeled water. Calculated EI (cEI) was determined as TEE corrected for the estimated change in body energy. Subjects completed the Eating Inventory., Results: rEI values were significantly lower than TEE values for all 3 dietary assessment methods (P < 0.05); there was no significant relation between rEI and TEE by any method. There was no significant difference in 100 x rEI:TEE between restrained and unrestrained eaters by any of the dietary assessment methods. When combined data from the 3 methods were used, 100 x rEI:cEI was not significantly different from 100% in unrestrained eaters (99 +/- 6.8%) but was lower in restrained eaters (89.1 +/- 5.3%; P < 0.05). There was a positive relation between hunger and 100 x rEI:TEE (P < 0.05)., Conclusions: Low hunger is associated with undereating relative to normal eating during measurement of dietary intake; high dietary restraint may be associated with a reduction in reporting of consumed foods. Dietary hunger and restraint assessed with use of the Eating Inventory may help to identify subjects likely to underreport dietary intake.

Until recently, the percentage of energy from dietary fat has been considered a primary determinant of body fatness. This review covers recent studies from our laboratory that challenge this notion. High and low fat diets matched for energy density, palatability and fiber resulted in similar mean voluntary energy intakes over 9 d; analysis of the individual foods in these diets showed that energy density and palatability were significant determinants of energy intake, independent of fat content. Path analysis further revealed that the influence of energy density on energy intake was in part direct, and in part indirect and mediated by palatability. In another study, dietary variety within food groups was shown to be an important predictor of body fatness, and the direction of the association depended on which food groups provided the variety, i.e., the variety of sweets, snacks, condiments, entrees and carbohydrates consumed was positively associated with body fatness, whereas the variety of vegetables was negatively associated. Last, a study of restaurant food and body fatness showed that the frequency of consumption of restaurant food was positively associated with body fatness, independent of education level, smoking status, alcohol intake and physical activity. Restaurant meals tend to be high in fat and low in fiber, and thus energy dense. Restaurants also typically serve a variety of palatable foods in large portions. The increasing variety of high energy foods available and the increasing proportion of household income spent on foods consumed away from home may help explain the U.S. national rising prevalence of obesity.

Inadequate energy intake is common in older individuals and is probably the major cause of unexplained weight loss. This summary highlights recent studies on possible causes of negative energy balance in older individuals suggesting that aging is associated with a significant impairment in the regulation of food intake that inhibits appropriate short-term and long-term compensation for normal fluctuations in energy intake. The combination of a reduced ability to regulate energy intake, decreased dietary variety, and disadvantageous social factors such as functional limitations, social isolation and depression, increases the risk of negative energy balance leading to weight loss in older individuals.

Background: Short-term experimental studies suggest that dietary variety may influence body fatness but no long-term human studies have been reported., Objective: The purpose of this study was to determine whether dietary variety within food groups influences energy intake and body fatness., Design: Seventy-one healthy men and women (aged 20-80 y), who provided accurate reports of dietary intake and completed a body-composition assessment, were studied., Results: Dietary variety was positively associated with energy intake within each of 10 food groups (r = 0.27-0.56, P < 0.05). In multiple regression analysis with age and sex controlled for, dietary variety of sweets, snacks, condiments, entrées, and carbohydrates (as a group) was positively associated with body fatness (partial r = 0.38, P = 0.001) whereas variety from vegetables was negatively associated (partial r = -0.31, P = 0.01) (R2 = 0.46, P < 0.0001). In separate models, both a variety ratio (variety of vegetables/variety of sweets, snacks, condiments, entrées, and carbohydrates) and percentage dietary fat were significant predictors of body fatness (controlled for age and sex, partial r = -0.39 and 0.31, respectively, P < 0.01). However, dietary fat was no longer significantly associated with body fatness when the variety ratio and dietary fat were included in the same model., Conclusions: Our data, coupled with those of previous short-term studies, suggest that a high variety of sweets, snacks, condiments, entrées, and carbohydrates coupled with a low variety of vegetables promotes long-term increases in energy intake and body fatness. These findings may help explain the rising prevalence of obesity.

There is little information on the effects of age on energy requirements in women. This issue was investigated in a cross-sectional study of 10 normal-weight young women aged 25.2 +/- 1.1 y (mean +/- SEM) and 10 normal-weight older women aged 74.0 +/- 1.4 y. In a 9-d study, measurements were made of free-living total energy expenditure (TEE) by using the doubly labeled water technique, body composition by using hydrodensitometry, and resting energy expenditure (REE) by using indirect calorimetry. Mean values for reported levels of strenuous activity were within the expected range in both groups (31 +/- 13 min/d in the young group and 7 +/- 2 min/d in the older group). Energy requirements expressed as the ratio of TEE to REE were 1.80 +/- 0.10 and 1.62 +/- 0.06 (P < 0.01) in the young and older group, respectively. When values for REE predicted from body weight (pREE) were used, as suggested in the current recommended dietary allowances (RDAs), the ratios of TEE to pREE in the two groups were 1.85 +/- 0.10 and 1.54 +/- 0.04 (P < 0.05). The RDAs significantly under-predicted the energy requirements of the young group (P < 0.05), but there was no significant underprediction in the older group. Although obtained in a relatively small number of subjects, these results provide no evidence to indicate that the current RDAs underestimate the energy requirements of older women, in contrast with previous observations of an underestimation of energy requirements by the RDAs in older men.

In order to test whether lactational capacity can be improved by dietary interventions, a nutritionally balanced supplement was provided under carefully controlled conditions to 130 nursing mothers in Keneba, The Gambia over 12 months. Maternal mean energy intake (+/- s.e.) increased from 1568 +/- 15 kcal/d (6.56 +/- 0.06 MJ/d) to 2291 +/- 14 kcal/d (9.59 +/- 0.06 MJ/d). Protein intake was in excess of the WHO/FAO recommended intake after supplementation and serious deficits of riboflavin, vitamin A, vitamin C and calcium were rectified. The supplement had no effect on breast-milk volume, compared with retrospective controls, at any stage of lactation or in any season of the year. There was no selective effect on women with poor milk outputs. The average milk protein concentration was slightly improved over the entire period of lactation (+ 6.6 per cent, P less than 0.01), but the total energy content was unchanged since an increase in breast-milk fat concentration (+ 7.9 per cent, n.s.) was offset by a decrease in the milk lactose concentration (- 7.6 per cent, P less than 0.01). Breast milk vitamin content was improved for those vitamins for which the supplement provided a significant proportion of the recommended dietary intake.

The energy intake of 143 pregnant and lactating Gambian women was measured prospectively each week for a year. Anthropometric, birth weight, and breast milk output measurements were also obtained. The average energy intakes (+/- SE) during the dry and wet seasons respectively were: pregnancy, 1483 +/- 22 and 1417 +/- 41 kcal/day; lactation (1st trimester), 1773 +/- 31 and 1474 +/- 42 kcal/day; lactation (subsequent trimesters), 1662 +/- 16 and 1413 +/- 37 kcal/day. Pregnant women gained 1.4 kg body weight per month in the dry season, but only 0.4 kg in the wet season. Lactating women gained weight in the dry season and lost weight in the wet season. Maternal nutritional status did not deteriorate with increasing parity. Mean birth weights (+/- SE) were: 2.94 +/- 0.07 and 2.78 +/- 0.11 kg in dry and wet seasons, respectively. Breast milk output and quality and early infant growth were close to values from well-nourished communities during the dry season, but deteriorated markedly during the wet season. Wet season energy intakes were clearly inadequate, but these results indicate that, despite being low by international standards, the dry season intake was compatible with a good lactational performance. Except for a somewhat low birth weight, which is partly explained by small maternal stature, progress during pregnancy was also remarkably normal during the dry season.

Objective:To examine characteristics of craved foods in relation to dietary energy restriction (ER) with high (HG) and low glycemic load (LG) diets.Design:Assessments of food cravings before and during a randomized controlled trial of HG and LG diets provided for 6 months.Subjects:Thirty-two healthy, overweight women aged 20–42 years.Measurements:Self-reported food cravings and dietary intake, body weight, weight history and measures of eating behaviors.Results:Foods craved at baseline were more than twice as high in energy density as the habitual diet (3.7±1.5 vs 1.7±0.3 kcal/g; P<0.001), and on average were lower in protein (P<0.001) and fiber (P<0.001) and higher in fat (P=0.002). There were no statistically significant changes in nutritional characteristics of craved foods after 6 months of ER. There was a significant relationship between reported portion size of craved food consumed at baseline and lifetime high body mass index (r=0.49, P=0.005). Additionally, there was a significant association between susceptibility to hunger and craving frequency at baseline, and there were significant relationships between hunger score, craving frequency, strength and percentage of time that cravings are given in to after 6 months of ER. In multiple regression models, subjects who lost a greater percentage of weight craved higher energy-dense foods at month 6 of ER, but also reported giving in to food cravings less frequently (adjusted R 2=0.31, P=0.009).Conclusion:High energy density and fat content, and low protein and fiber contents were identifying characteristics of craved foods. The relationships between craving variables and hunger score suggest that the relative influence of hunger susceptibility on cravings may be important before and especially after ER. Portion size of craved foods and frequency of giving in to food cravings appear to be important areas for focus in lifestyle modification programs for long-term weight loss.International Journal of Obesity (2007) 31, 1849–1858; doi:10.1038/sj.ijo.0803672; published online 26 June 2007 [ABSTRACT FROM AUTHOR]

Objective: To compare relative associations of eating patterns and dietary composition with body mass index (BMI) in younger (aged 20-59 years, n=1792) and older (aged 60-90 years, n=893) participants in the Continuing Survey of Food Intakes by Individuals, collected 1994-1996.Methods: Data from two 24-h dietary recalls from individuals reporting physiologically plausible energy intake (within +/-22% of predicted energy requirements, based on previously published methods) were used.Results: Mean reported energy intake was 96 and 95% of predicted energy requirements in younger and older subjects, respectively. Older subjects were less likely than younger subjects to skip a meal, but snacking was common in both age groups. Fiber density was significantly higher in the older group. A higher BMI in both age groups was associated with a higher total daily energy intake, and higher energy intakes at all eating occasions. In both age groups, eating frequency was positively associated with energy intake, and eating more than three times a day was associated with being overweight or obese. In the younger group but not the older group, a lower fiber density coupled with higher percentage of energy from fat was independently associated with having a higher BMI.Conclusions: While no one eating occasion contributes more than any other to excess adiposity, eating more often than three times a day may play a role in overweight and obesity in both younger and older persons. A reduced satiety response to dietary fiber in addition to lower energy expenditure may potentially further contribute to weight gain in older persons. [ABSTRACT FROM AUTHOR]

Recent studies have suggested a short-term impairment in the regulation of food intake in older adults, but further studies are needed to determine if a longer-term impairment exists and to identify underlying causes. Changes in body weight and composition were measured over a 6-week underfeeding study and a 6-month follow-up period in healthy young (n = 23) and older (OLD, n = 18) men and women. The young adults were either normal weight (YNW, n = 12) or overweight (YOW, n = 11). Energy intakes during underfeeding were 896 +/- 18 (SEM) kcal less than weight-maintenance energy requirements determined prior to underfeeding. In addition, changes in perceived hunger during underfeeding were monitored in a subgroup (n = 19). OLD and YOW subjects lost significantly more weight during underfeeding than did YNW subjects (p = .025 and .000, respectively), and they did not gain back significant weight in the 6-month follow-up. In addition, OLD subjects reported a significantly lower frequency of hunger during underfeeding (p = .05). There was no significant difference among groups in the relationship between weight lost and fat-free mass lost. Healthy OLD adults have an impaired ability to regulate food intake over at least 6 months following underfeeding compared with YNW adults, and a reduction in their perceived frequency of hunger may be a contributing factor. [ABSTRACT FROM AUTHOR]