Personal factors influence the diet quality of young adults

April 29, 2021

Late-night, greasy kebabs after a big night out? A sneaky chocolate bar and strawberry milk on the way to work or lectures? Many Australian young adults eat pretty poorly. But why?

Young adults are eating unhealthy diets

Did you know that one-third of Australian young adults’ total dietary intake comes from discretionary foods—that’s a lot! The Australian Dietary Guidelines discourage eating discretionary foods, which are foods high in saturated fat, added sugars and salt, such as potato chips, sausage rolls, chocolate and cakes. Additionally, less than five per cent of young adults eat the recommended serves of fruits and vegetables (2 and 5 respectively). Consumption of fruits, vegetables and other healthy foods, such as wholegrain and high-fibre grain foods, lean meats and meat alternatives and low-fat dairy products, is encouraged in the Australian Dietary Guidelines. The unhealthy diets of many young adults have major ramifications for their future health and wellbeing.

How can we check whether the diets of Australian young adults are healthy or unhealthy? A diet quality index is a useful way to measure overall diet in young adults because it can tell us about the diversity and quality of the foods and beverages consumed as part of adietary pattern. It also tells us how closely the diets of young adults align with the Australian Dietary Guidelines. In our study recently published in Appetite, we used the Dietary Guideline Index (DGI-2013) to estimate the diet quality of 625 young adults from Victoria. We used cross-sectional data from the Measuring Eating in everyday Life Study, which used a real-time food diary app for smartphones to collect data on these young adults’ diets.

What influences the diet quality of young adults?

Life changes so much when you’re a young adult! For those of us who have already been there, remember when you moved out of home, started a new job, began or ended a relationship or started a family? For those of you who aren’t there yet—there’s a lot to look forward to! But many of these changes can have significant adverse effects on lifelong dietary behaviours. Because of this, we thought it was important to understand what influences diet quality in young adults. In our study, we aimed to assess 30 potential factors that influence diet quality in young adults. We used a social-ecological framework to categorise these factors into one of three types: individual (e.g., self-efficacy), social (e.g., relationship status) and environmental (e.g., proximity to food destinations).

We found that young adults had a higher diet quality if they believed they could make healthy food choices (self-efficacy), had more time to prepare food and had adequate access to healthy food. Young adults also ate more healthily if they were born in Australia, worked in a non-trade job and made a meal with vegetables each day. We didn’t find any social or environmental correlates that influenced young adults’ diet quality.

Young adulthood is a critical life stage and full of changes that can positively or negatively influence lifelong dietary habits. Our study shows that to improve the healthiness of young adults’ diet, we need to focus on factors such as improving their confidence to make healthy food choices. We also need further research into the social and environmental factors of young adults’ diet quality to better understand how these factors influence their dietary intake.

So how can young adults improve their diet?

Our findings highlight the importance of healthy eating habit in young adults, as behaviours established at this early stage often track into later life, increasing the risk of obesity and chronic disease. This year the United Nations has designated 2021 the International Year of Fruits and Vegetables. In line with their recommendations, young adults can improve their diet quality by incorporating more fruits and vegetables into their diets.

Some tips to increase vegetable intake:

• Make a vegetable omelette for breakfast with spinach and mushrooms.
• An easy way to add a serve of vegetables is to add a side salad to your main meal.
• Try new vegetables in place of old favourites, such as mashed sweet potatoes and pumpkin in place of plain white mashed potatoes.

By doing this, young adults will not only improve their healthy eating habits and overall health but will begin to address some of the individual factors (like improving their confidence with food and preparing a meal with vegetables daily) that influence their diet quality, too!

Meaghan Sexton-Dhamu completed her Master of Hu man Nutrition at Deakin University in 2018. Her thesis examined the correlates of diet quality in young adults and was supervised by the Institute for Physical Activity and Nutrition researchers Dr Katherine Livingstone and Prof Sarah McNaughton. Meaghan plans to continue her research by applying for a PhD Scholarship within IPAN in 2021.