New large-scale study recommends nutritional support for smokers who fear weight gain if they quit

13 May 2024 --- Smokers tend to eat less and have a lower body weight and body mass index (BMI) than non-smokers, while many associate quitting with the fear of weight gain. A new study involving 83,000 UK adults highlights the need for nutritional and weight management support for smokers, especially those looking to drop the dangerous habit.

The study conducted by researchers at Loughborough University and the University of Leicester, UK, will be presented at this year’s European Congress on Obesity held in Venice, Italy (May 12–15 ).

“The worry of gaining weight is a common reason for smokers not attempting to quit or being unsuccessful in their attempts to quit smoking,” says chief investigator Dr. Scott Willis from Loughborough University. 

“Our findings indicate that smoking is associated with eating behavior patterns consistent with reduced food intake and worse diet quality, characterized by frequent intake of fried food and adding salt and sugar to meals. This could help explain the weight gain commonly observed when people stop smoking.”

Lead author Arwa Alruwaili, from the same university, adds: “These findings reinforce the importance of providing nutritional and weight management support in the large-scale efforts to prevent and reduce smoking in the general UK population. This could help to promote more successful quit attempts, and to improve people’s eating habits and the many diseases that are related to both of these major health risks.”

The findings highlight the importance of providing nutritional and weight management support in the large-scale efforts to prevent and reduce smoking.Less food, but unhealthier 
The cross-sectional study considers data from 83,000 UK residents aged over 18 collected during health assessment programs conducted between 2004 and 2022 by the British healthcare charity Nuffield Health. 

The participants were divided into two groups, with 6,454 being smokers and the remaining 77,327 nonsmokers. On average, the smoking group was 40 years old, had a BMI of 26 and 37% was female. The non-smoking group was 44 years of age, on average, had a BMI of 25.7, with 38% women. 

All involved in the study filled out a questionnaire providing information about their age, socioeconomic status, smoking status and eating and dietary behaviors. Participants’ BMI was also measured as part of the evaluations. 

The researchers adjusted the data for age, sex and socioeconomic status. Compared to non-smokers, smokers were twice as likely to skip meals and 50% more likely to go more than three hours without food. They were also more likely to have fewer meals per day and found it more difficult to leave unfinished food on their plate, indicating a struggle with stopping to eat when full. 

Smokers were found to be 35% less likely to snack between meals but also less likely to eat because of boredom or reward-seeking. Also compared to non-smokers, those who smoke were found to be 8–13% less likely to seek out sweet foods between meals and for dessert, while being 8% more likely to eat fried food, 70% more likely to add salt and 36% more likely to add sugar to meals. 

Altered eating habits
The researchers point out that several of these data points were impacted by age, sex and socioeconomic status. The relationships between smoking and the highlighted eating behaviors were most strongly and consistently observed among older generations.

The relationship between smoking and increased likelihood of adding salt and sugar to meals was stronger among men than women. This is linked to the possibility of male smokers being more susceptible to unhealthy dietary patterns than women. 

The findings suggest that smokers tend to eat less healthy, and have less healthy eating habits, which could explain why they often tend to gain weight after quitting. Based on this, the team of researchers emphasizes the need for individuals seeking to improve their health through quitting to have access to nutritional and weight management support.

The results are based on observational findings. The researchers assert that a definite cause-and-effect link between smoking and altered eating habits cannot be found entirely based on a population-based study. 

They further point out that this analysis does not take into account the influence of other risk factors associated with higher likelihood of smoking, as well as with disordered eating, including levels of psychological health and physical activity levels. Recall bias is also relevant, as the study is based on self-reported eating habits. 

By Milana Nikolova