Are you able to breeze through a day at work without so much as thinking about snacks, only to get home and spend the evening as a slave to the fridge? Well, according to the latest research, science could be to blame for your after-hours cravings.
New findings by scientists in the USA have shown that, in the evening, we experience alterations to the levels of hormones that influence appetite – potentially causing us to overeat and, in turn, gain weight.
Researchers looked into the eating habits of 32 adults aged 18-50, half of whom had been diagnosed with a binge eating disorder and all of whom were overweight. Each participant was asked to take part in two experiments. The first required them to fast for eight hours before consuming a ‘liquid meal’ (consisting of 608 calories) at 9am, while the second involved an identical period of fasting followed by a liquid meal at 4pm.
One hundred and thirty minutes after the meal, participants underwent a stress test (placing their hand in a bucket of cold water for several minutes) and then, after a further 30 minutes, were offered their pick of an unhealthy buffet, made up of foods such as pizza, chips and cookies. Prior to each experiment, individuals were asked to report their levels of hunger and fullness.
Overall, it was found that volunteers were hungrier in the evening than in the morning. Levels of ghrelin, which is the hormone that stimulates appetite, were found to be higher after the consumption of an afternoon meal compared with the morning meal, while levels of the PYY hormone (responsible for reducing appetite) were lower in the evening.
Additionally, all participants saw their ghrelin levels increase alongside their stress levels, and the findings further suggest that stress may have a greater influence on hormones in the evening. The report reads: ‘Eating late in the day is common, and stress can induce eating… Afternoon/evening may be a high-risk period for overeating, particularly when paired with stress exposure, and for those with binge eating.’
Adding to this was study author Susan Carnell, who said:’The good news is that having this knowledge, people could take steps to reduce their risk of overeating by eating earlier in the day, or finding alternative ways to deal with stress.’
The study was published in the International Journal of Obesity.