Scientists have for the first time used anonymous data from pre-payment food cards to get a unique insight into the eating habits of first year university students.
Data scientists at the University of Leeds have been able to build a detailed picture of what 835 students ate, and when, by analysing the data linked to their pre-payment food cards.
The cards revealed what they were buying in the campus refectory and associated food outlets.
The analysis gives the most accurate picture to date of first year student diets. Many previous studies have used food diaries, but their accuracy can be variable because they rely on the student remembering exactly - and being honest about - what they have eaten.
Dr Michelle Morris, a University Academic Fellow in Health Data Analytics based at Leeds Institute for Data Analytics, said understanding student diet had public health implications.
Previous studies in the UK and the US have shown that "fresher" students are at risk of weight gain, probably as a result of the lifestyle changes that come with starting university.
In the US, they talk of the "Freshmen 15", the 15lbs (6.8kg) that students put on. In the UK, research indicates the average student gains 7.7lbs (3.5kg).
The findings, Assessing diet in a university student population: A longitudinal food card transaction data approach, have been published in the British Journal of Nutrition.
The study, which pre-dated the coronavirus outbreak and followed the students aged 18 to 24 over their first semester (12 teaching weeks), revealed student eating habits which clustered around seven dietary behaviours:
- Vegetarian: with popular purchases being salads, breakfast cereals, yoghurt and fromage frais and a notable absence of meat products
- Omnivores: which included the most average amounts of all products purchased, with above average amounts of ice cream, desserts and cakes, breakfast cereals and fish.
- Dieters: with above average purchases of soups, pasta, noodles and salad.
- Dish of the Day: which included above average purchases of meat and meat products.
- Grab and Go: which included above average purchases of sandwiches, crisps, nuts and eggs.
- Carb Lovers: with bread, cheese, egg products and pasta being among the top picks.
- Snackers: with confectionery, crisps, nuts being above average choices.
Dr Morris, said the dietary patterns were ranked on the basis of "healthfulness", with vegetarian the most healthful and snackers being the least.
She added: "Our analysis shows that although some students followed one dietary pattern throughout the semester many switched between them.
"Some students moved from a more healthy to a less healthy pattern; for example, some vegetarians switched to an omnivore diet; and vice versa with some of the students who started off as snackers the least healthful diet - did move to the Dish of the Day which offered a more balanced range of food options.
"Worryingly perhaps, the most popular move was from a dieter pattern, to the snacking pattern."
Females were found to be heavily represented among the vegetarians (88%) and dieters (80%) while the men dominated the dish of the day (84%) and grab and go (62%) diet patterns.
This information could be used to target information about healthier eating to students.
Dr Morris said the most popular dietary pattern amongst the slightly older students, those aged between 20 and 24, was the omnivore pattern of eating that could be due to the fact that they may already have lived away from home and settled into a more varied dietary pattern.
She said: "The information from this analysis reveals the pattern of the students eating habits, and how that changes over time. That is information that could be used to target information about healthier eating to students.
"Research has shown that adult eating habits take root early in adulthood. So, time spent at University is a great time to encourage healthy eating behaviours that could remain with them for life."
The research was funded by the Economic and Social Research Council through a Strategic Network for Obesity grant. Maintaining the anonymity of the students was of utmost importance at all stages of the research.
Notes to editor
For further information or interview requests, please contact University of Leeds Media Relations and Communications Officer David Lewis via d.lewis@leeds.ac.uk