Consequence of omitting or adding a meal in man on body composition, food intake, and metabolism.

Objective: To investigate in man the consequence on body composition and related biological and metabolic parameters of omitting or adding a meal.

Research Methods And Procedures: Twenty-four young normal-weight male subjects were recruited, 12 usual four-meal and 12 usual three-meal eaters, differing only in the consumption of an afternoon meal. They omitted or added a fourth meal during a 28-day habituation period and were asked to report their intake on three 3-day occasions.

Highlighting the positive impact of increasing feeding frequency on metabolism and weight management.

Research on feeding frequency started more than 20 years ago and some studies have shown evidence of nutritional benefits, especially on metabolism and body weight management. Advice on feeding frequency could play an important role in public health policies by reducing levels of overweight and obesity, the prevalence of which has dangerously increased in most countries over the last few decades. The 17th International Congress of Nutrition brought to the forefront the benefits of increasing feeding frequency (i.

A role for glucose and insulin preprandial profiles to differentiate meals and snacks.

A physiological distinction between eating occasions may help account for contradictory findings on the role of eating frequency in energy homeostasis. We assessed this issue using a midafternoon eating occasion known in France as the goûter that often consists of snack foods. Among the 24 male subjects, 8 habitually consumed four meals per day, i.

Snacks consumed in a nonhungry state have poor satiating efficiency: influence of snack composition on substrate utilization and hunger.

Background: Several epidemiologic studies suggest that snacking may play an etiologic role in obesity.

Objective: We assessed the behavioral and metabolic consequences of a high-carbohydrate (HC) or high-protein (HP) snack consumed 215 min after lunch, thereby investigating ways that snacking in a nonhungry state could be involved in the etiology of obesity.

Design: Eight lean young men attended 3 sessions (basal, HP snack, and HC snack) in a counterbalanced order with 2 wk between sessions.

Substrate oxidation and control of food intake in men after a fat-substitute meal compared with meals supplemented with an isoenergetic load of carbohydrate, long-chain triacylglycerols, or medium-chain triacylglycerols.

Background: It has been suggested that hunger may be delayed and food intake reduced under metabolic conditions that spare carbohydrate oxidation.

Objective: Our objective was to examine the role of glucose metabolism in the control of food intake in men by using medium-chain triacylglycerols (MCTs) to spare carbohydrate oxidation.

Design: In 10 male volunteers, isolated and deprived of any time cues, we studied the effects of 4 lunches on hunger ratings, the duration of satiety, the amount of food ingested at dinner, energy expenditure, substrate oxidation, and plasma variables until the time of the dinner request.

An endocrine and metabolic definition of the intermeal interval in humans: evidence for a role of leptin on the prandial pattern through fatty acid disposal.

Background: It has been proposed that leptin provides a hormonal link between adipose stores and food intake.

Objective: This study investigated the role of leptin in the prandial pattern.

Design: In experiment 1, a spontaneous prandial pattern was recreated in 6 young, normal-weight men who were deprived of time cues and had blood withdrawn continuously at a frequency of one tube every 5 min.

Effects of macronutrient content and energy density of snacks consumed in a satiety state on the onset of the next meal.

We examined the effects of nutrient composition of a 1 MJ afternoon snack, consumed in a satiety state, on the spontaneous onset of the next meal in 11 young male subjects deprived of any temporal cues. All subjects attended four experimental sessions scheduled 2 weeks apart. The first, baseline, session served to establish: (1) the subjects' ad libitum lunch intake, (2) the latency of the spontaneous request for dinner following lunch, (3) ad libitum food intake at dinner.

Metabolic and behavioral consequences of a snack consumed in a satiety state.

Background: In view of the influence of dietary habits on obesity, human eating patterns merit study.

Objective: We investigated the behavioral and biological consequences of consumption of a 1-MJ snack by subjects in a satiety state.

Design: Eleven lean young men were deprived of time cues and subjected to continuous blood withdrawal over each of 4 sessions scheduled 2 wk apart.

Influence of medium-chain and long-chain triacylglycerols on the control of food intake in men.

Hunger may be delayed and food intake reduced under metabolic conditions that spare carbohydrate oxidation, especially during oxidation of medium-chain triacylglycerols (MCTs) or monounsaturated triacylglycerols. In 12 healthy, adult, male volunteers isolated and deprived of any time cues, we compared the effects of 4 high-carbohydrate breakfasts (1670 kJ) supplemented either with a fat substitute (Sub; 70 kJ) or with 1460 kJ fat as monounsaturated long-chain triacylglycerols (LCT-U), saturated long-chain triacylglycerols (LCT-S), or MCTs. In the first session we investigated the effects of these breakfasts on the following food intake variables: hunger ratings at repeated intervals, the time until the spontaneous request for the next 2 free-choice meals, and the amount of food consumed.

Influence of PROP-sensitivity on taste perceptions and hedonics in French women. A study performed without retronasal olfaction.

Detection threshold for the taste of PROP (6-n-propyl thiouracil) in aqueous solution was determined in 173 French Caucasian women deprived of retronasal olfaction by blowing an air stream into the nostrils. As expected, the detection thresholds were bimodally distributed, although as many as 73% of the subjects had thresholds above the antimode concentration and therefore qualified as non-tasters. Detection threshold, difference threshold, intensity perceptions and preference ratings were then determined for NaCl, sucrose, caffeine, Na saccharin and naringin in 20 tasters and 20 non-tasters.

Is pleasantness of biscuits and cakes related to their actual or to their perceived sugar and fat contents?

Perceptions of sugar, fat and moisture contents, as well as their influences on pleasantness were investigated in commercial foods. One-hundred-and-two-normal-weight men rated the "pleasantness", "flavour intensity", "moisture", "sweetness" and "fatness" of 39 different biscuits and cakes. Sugar content was accurately perceived up to a maximum content of about 33% weight/weight.

The effect of soup on satiation.

We compared the influence of three solid/liquid preloads to a no-preload condition given at lunchtime on hunger ratings and energy intake of the lunch and subsequent dinner in 12 lean and 10 overweight young men. The preloads (vegetables and water, strained vegetable soup, chunky soup) were of the same composition and volume but differed in distribution of nutrients between the liquid and the solid phases, and in the size of solid particles. Hunger ratings were reduced by the preloads; there was a significantly greater suppression of hunger after the chunky soup than after the vegetables and water.

Satiety power of dietary fat: a new appraisal.

Accumulating evidence suggest that a good way to compare the satiety power of meals with different compositions or energy contents is to measure the onset latency of the next meal when freely requested by subjects deprived of any time cues. This study was performed in normal-weight young men (aged 19-24 y) isolated from time cues. At sessions 1 and 2, we studied the effects of two high-carbohydrate pasta lunchs with either 50 g low-energy butter substitute (lunch A) or 50 g butter (lunch B) on hunger ratings, on the latency of the dinner request, and on energy and nutrient intakes at the offered ad libitum dinner.

Cephalic phase responses to sweet taste.

The sweet taste of nonnutritive sweeteners has been reported to increase hunger and food intake through the mechanism of cephalic-phase insulin release (CPIR). We investigated the effect of oral sensation of sweetness on CPIR and other indexes associated with glucose metabolism using nutritive and nonnutritive sweetened tablets as stimuli. At lunchtime, 12 normal-weight men sucked for 5 min a sucrose, an aspartame-polydextrose, or an unsweetened polydextrose tablet (3 g) with no added flavor.

Exercise-training reduces BAT thermogenesis in rats.

In the energy balance equation, physical activity represents one component of energy expenditure. From various studies it appears that exercise-training does not affect clearly thermogenesis which depends on brown adipose tissue (BAT) activity. In the present work we examine how exercise-training can influence food intake and body weight regulation in relation to BAT thermogenesis.

The effects of aspartame versus sucrose on motivational ratings, taste preferences, and energy intakes in obese and lean women.

This study examined the effects of four breakfast preloads of different sweetness and energy content on motivational ratings, taste preferences, and energy intakes of 12 obese and 12 lean women. The preloads consisted of creamy white cheese (fromage blanc) and were either plain, sweetened with sucrose or aspartame, or sweetened with aspartame and supplemented with maltodextrin. Their energy content was either 300 kcal (1,255 kJ) or 700 kcal (2,929 kJ).

Exercise training modifies nutrient self-selection in rats.

Few studies have examined the effects of exercise training on macronutrient self-selection in rats. It has been observed that trained rats decreased carbohydrate and increased fat and protein intakes. In the present experiment, total energy intake and macronutrient self-selection were examined in adult male rats placed on a self-selection regimen and submitted to 2 h of treadmill exercise daily for 20 days at the beginning of the nocturnal period.

Effect of a fat-reduced dish in a meal on 24-h energy and macronutrient intake.

A covertly fat-reduced and low-calorie dish was provided at lunchtime once a week to normal-weight human subjects. A normal-calorie version of the dish was served for the first 3 weeks, the low-calorie version for the following 4 weeks and the normal-calorie version again for the last 3 weeks. Participants did not compensate for the 840-kJ (201 kcal) fat reduction of their main dish during the lunchtime meal.

Free food choice after acute exercise in men.

A buffet-type meal was presented to 28 young men after participation in various athletic activities and to 30 subjects kept inactive. At 30 min after 2h of exercise, total energy intake was about 25% greater than after the rest situation. The food choices after exercise yielded an energy intake from proteins that was significantly larger than after rest, but not of carbohydrate or fat.

Energy balance in an inbred strain of rats: comparison with the Wistar strain.

Food intake and body weight gain were examined in two groups of male rats (7 weeks): an inbred strain, Dark Agouti (DA, n = 12) and a noninbred strain, Wistar (n = 13). The animals were allowed to select their diet from separate sources of the three macronutrients protein, fat, and carbohydrate. After 10 days of adaptation to the diets, body weights and food intakes were measured for 3 weeks.