Poster Presentation ANZOS-ASLM-ICCR 2019

Quality or quantity? Comparing effects of ad-libitum and limited access to a western-style cafeteria diet on adiposity and cognition (#157)

Ching Ho 1 , Michael D Kendig 1 , Margaret J Morris 1
  1. School of Medical Sciences, UNSW Sydney, Sydney, NSW, Australia

Poor diet is among the leading risk factors for morbidity and mortality worldwide. Studies in rodents show that high-fat, high-sugar (HFHS) diets induce obesity, metabolic and cognitive dysfunction, with cognitive impairment observed prior to the onset of obesity. While caloric and time restricted diets have proven benefits for body weight and metabolic health, the impact of restricted access to unhealthy diets on metabolic and cognitive function is largely unknown. This study compared ad-libitum and restricted access to a palatable western-style ‘cafeteria’ diet (CAF) high in sugar and saturated fat. Adult male Sprague-Dawley rats (n=12/group) received ad libitum or restricted access to chow (CHOW and CHOW-R) or cafeteria diet (CAF and CAF-R) for 6 weeks. Food intake was measured daily, allowing for the energy intake of restricted groups to be yoked to the CHOW group’s consumption on the previous day. Restricted groups were given their daily food ration at the onset of the dark phase and tended to consume it within the first 6-h. The CAF-R group received the same foods as the CAF group but in smaller portions. Anxiety-like behaviour was assessed in the Elevated-Plus Maze (EPM) in week 4 and object and place recognition memory were assessed in week 6. Energy intake, weight gain and fat mass were significantly elevated in the CAF group. Notably, retroperitoneal fat mass was significantly elevated in the CAF-R relative to CHOW-R group. while both continuous and restricted access to CAF diet increased fasting blood glucose. Diets did not alter anxiety-like behaviour in the EPM, though restricted groups were more active. Results indicate adverse metabolic effects of CAF diet even when access is time-restricted and isocaloric with a control diet.