Food intake, energy balance and body weight control

Abstract

Obesity is a multifactorial and complex affectation that is characterized by a long-term excess energy intake (EI) above energy expenditure (EE). Since fat oxidation seems to be dependent on SNS activation and also seems to remain acutely unaffected by fat intake, this macronutrient is certainly partly responsible for this situation. In addition, high-fat intake does not induce as potent satiety signals or a compensation effect on subsequent EI as do diets rich in carbohydrates or proteins. Moreover, since alcohol intake acutely inhibits fat oxidation and does not promote subsequent compensation for its energy content, it should consequently be regarded as a substrate which can induce a positive energy balance under free-living conditions. Thus, in a weight reducing context, each energy substrate should be manipulated while taking into account its speci®c characteristics. Obesity has also often been associated to a decreased sympathetic nervous system (SNS) activity, hence sympathomimetic agents have been proposed as a possible way to partially correct this situation. Two of these agents are the widely consumed caffeine (CAF) and the pungent principle of hot red pepper, capsaicin (CAP), which acutely increase EE and reduce EI under some circumstances. Furthermore, other factors like dietary ®bers, that have been shown to increase satiety and fullness, and reduce EI in some cases, should also be considered.

Effects of CH-19 Sweet, a Non-Pungent Cultivar of Red Pepper, in Decreasing the Body Weight and Suppressing Body Fat Accumulation by Sympathetic Nerve Activation in Humans

“…Sympathomimetic compounds such as capsaicin have been assumed to correct the decreased SNS activity proposed as a possible factor leading to obesity. 25) Consequently, CH-19 Sweet may have the potential to improve the decreased SNS activity, which is an etiological feature of obesity. In addition, the amount of weight loss due to the repeated intake of CH-19 Sweet for two weeks was positively correlated with the degree of SNS activation by a single administration of CH-19 Sweet.…”

Clinical implications of leptin and its potential humoral regulators in long-term low-calorie diet therapy for obese humans

“…A long-term caloric restriction therapy is employed as a standard therapeutic strategy for obesity, but sometimes in vain (National Institutes of Health, 1993;Wadden et al, 1989;Doucet & Tremblay, 1997). A therapeutic failure is due, at least in part, to loss of motivation to sustain behaviors required for continuing weight reduction (Wadden et al, Figure 3 Time course in plasma leptin levels (a), relative change in the leptin=BMI ratio (b), insulin (d), T3 (e) and FFA (f) during diet therapy (open circle BDD; closed circle LCD; *P < 0.05, **P < 0.01, vs the initial value).…”

Effects of test-meal palatability on compensatory eating following disguised fat and carbohydrate preloads

“…1,2 In order to develop effective treatments for obesity we need to understand what motivates people to overeat. The regulation of food intake is complex, involving the integration of orosensory, gastro-intestinal and metabolic signals.…”

“…This is important since there is evidence that obesity may involve abnormal responses to palatability 3 and disrupted satiety and energy balance. 2,4 Understanding how palatability and satiety interact in normal-weight individuals should allow us to predict how disruption to this relationship could lead to obesity.…”