People who eat their main meal at night consume more calories than those who dine earlier, according to a new study. They also tend to have a lower quality of diet than people who eat their main meal earlier in the day, suggest the findings.
Researchers say that their study of more than 1,100 British adults indicates a link between eating a larger proportion of one's daily energy intake during the evening and having a higher total energy intake and lower quality of diet. In recent years there has been a growing interest in how the timing of eating can influence metabolism and other physiological processes.
Previous research has shown that sensations of hunger follow a strong daily rhythmic pattern and are often most intense later in the day. The phenomenon could influence both the type and amount of food we eat. Judith Baird and colleagues at the Nutrition Innovation Centre for Food and Health (NICHE) at Ulster University wanted to investigate the association of energy intake (EI) during the evening on total EI and diet quality.
They selected a group of 1,177 adults aged 19 to 64 years from the UK National Diet and Nutrition Survey which began in 2008 and collects detailed information on food consumption, nutrient intake and nutritional status.
The participants were split into four groups based on the proportion of their daily EI consumed after 6pm, from the lowest with under 31.4 percent, through to the highest whose evening consumption accounted for more than 48.6 percent of their EI.
Diet quality was assessed by scoring the food diaries kept by the participants using the Nutrient Rich Food Index, which classifies and ranks foods according to the ratio of important nutrients they contain relative to their energy content.
Across the whole sample group, eating during the evening provided an average of 39.8 per cent of daily EI. The research team found a significant variation in total EI across the different groups, with individuals in the lowest band of evening EI consuming fewer calories in total over the day than those in the other three groups.
Quality of diet also differed across the groups with participants who consumed the largest proportion of their EI in the evening having a "significantly worse" score on the Nutrient Rich Food Index than those in the rest of the groups. PhD researcher Ms Baird said: "Our results suggest that consuming a lower proportion of EI in the evening may be associated with a lower daily energy intake, while consuming a greater proportion of energy intake in the evening may be associated with a lower diet quality score."
She added: "Timing of energy intake may be an important modifiable behaviour to consider in future nutritional interventions. Further analysis is now needed to examine whether the distribution of energy intake and/or the types of food consumed in the evening are associated with measures of body composition and cardiometabolic health."
The findings are due to be presented at the European and International Conference on Obesity.