Effects of Caloric Intake and Feeding Frequency on Carbohydrate Metabolism of the Rat

Abstract

The relationship between quantitative nutrient intake and periodicity of food ingestion on the adaptations of carbohydrate metabolism was studied. Glucose and insulin tolerance tests were conducted on animals that had eaten ad libitum (con trols), were pair-force-fed or force-fed 80% of the nutrient intake of the others. It was found that, compared with the controls, a) the underfed rat was more reactive, the fully-force-fed animal less responsive, to the hypoglycémieeffects of insulin and b) the undernourished rat disposed of a glucose load at a faster rate, the pair-forcefed rat at a slower or equal rate. The results of glucose tolerance tests performed on relatively undernourished rats "trained" to eat for 2 hours/day or pair-fed animals eating aliquots of their ration hourly were similar. In vitro studies with diaphragms and epididymal fat pads (glucose uptakes and insulin sensitivities) of animals that had eaten ad libitum or were force-fed either 100% or 80% of the nutrient intake of the controls yielded data that do not appear to account fully for the in vivo findings. It is concluded that in studies of metabolic adaptations to altered feeding frequency, one should use pair-fed animals given "optimal" amounts of nutrients, which in this case required force-feeding to equalize intake at the ad libitum level.

A systemic approach to explore the flexibility of energy stores at the cellular scale: Examples from muscle cells

“…Not only the quantity of food is important for energy metabolism, but also the feeding frequency affects the dynamics of energy storage, energy metabolism (Cohn and Joseph, 1970;Leveille, 1972), and the efficiency of energy use (Allee et al, 1972;Le Naou, 2014). Indeed, animals are intermittent feeders and limited access to feed during the day constrains their intermediary metabolism.…”

Influence of Alterations in Meal Frequency on Lipogenesis and Body Fat Content in the Rat

“…If the meal-eater is force-fed a quantity of food equal to that consumed by the nibbler, the meal-eater will accumulate more body fat than the nibbler (1)(2)(3). If the meal-eater is allowed food for only 2 hr per day, it will consume about 20% less food than the nibbler but will grow at the same rate as the nibbler (4).…”

Studies on Lipid and Carbohydrate Metabolism in the Rat

“…However, it would seem that all sets of data are suspect since the K values presented here and those reported by Chlouverakis et ah {1970) were higher than those reported in healthy men (Wahlberg, 1966) and undoubtedly refleeted the loss of glucose in the urine, whilst the K values listed by Cohn and Joseph (1970) were very low and would be diagnostic of diabetes if applied to humans. Cohn and Joseph (1970) concluded, on the basis of their findings and the reports of others, that meal feeding does not reduce insulin tolerance but, rather, the redueed insulin tolerance observed in meal-fed rats is caused by the reduced caloric intake which usually occurs when rats are meal fed on an ad libitum basis. Tlie present findings in 16 week old rats suggest that neither meal feeding nor caloric restriction affect insulin tolerance.…”