Visual food cues decrease postprandial glucose concentrations in lean and obese men without affecting food intake and related endocrine parameters

Abstract

The abundance of highly palatable food items in our environment represents a possible cause of overconsumption. Neuroimaging studies in humans have demonstrated that watching pictures of food increases activation in brain areas involved in homeostatic and hedonic food cue processing. Nevertheless, the impact of food cues on actual food intake and metabolic parameters has not been systematically investigated. We tested the hypothesis that watching high-calorie food cues increases food intake and modifies anticipatory blood parameters in lean and especially in obese men. In 20 normal-weight and 20 obese healthy fasted men, we assessed the effects of watching pictures of high-calorie food items versus neutral contents on food intake measured during a standardized test buffet and subsequent snacking as well as on glucose homeostasis and endocrine parameters. Compared to neutral pictures, viewing food pictures reduced postprandial blood glucose concentrations in lean (p = 0.016) and obese (p = 0.044) subjects, without any differences in insulin or C-peptide concentrations (all p > 0.4). Viewing food pictures did not affect total calorie intake during the buffet (all p > 0.5) and snack consumption (all p > 0.4). Concentrations of ghrelin, adrenocorticotropic hormone (ACTH), cortisol, and glucagon also remained unaffected (all p > 0.08). These data indicate that preprandial processing of food cues curbs postprandial blood glucose excursions, without immediately affecting eating behavior in normal-weight and obese men. Findings indicate that exposure to food cues does not acutely trigger calorie overconsumption but rather improves the glucoregulatory response to food intake.

Visual stimulation with food pictures in the regulation of hunger hormones and nutrient deposition, a potential contributor to the obesity crisis

“…The consequences of the upregulation of insulin, GIP and GLP-1 in response to visual food cues are well reflected in terms of the differences in blood glucose levels. Particularly in study I, in which we observe a trend in glucose levels indicating the difference between the S and NS day 15 minutes after the exposure to pictures (11:30 am), confirming previous report [78]. Therefore, we propose a model in which food cues provoke GIP and GLP-1 secretion.…”

Ghrelin, a gastrointestinal hormone, regulates energy balance and lipid metabolism

“…However, Kunath et al [ 90 ] did not find any evidence for the potential of ghrelin acting as a short-term cognitive enhancer in humans. It has been found that viewing food pictures does not affect total calorie intake and ghrelin levels, but improves postprandial glucose levels [ 91 ].…”

Reduced Hedonic Valuation of Rewards and Unaffected Cognitive Regulation in Chronic Stress

“…In our study, both groups presented a decreased in insulin, glucose, and cortisol levels after the fMRI task. Thus, the effects of fasting might have potentially surpassed the effects of stimulation with food pictures (Brede et al, 2017). Nonetheless, this hypothesis needs further testing.…”