British diets lack variety in plant-based foods, new study reveals
UK consumers may not be eating a wide enough variety of plant-based foods to support long-term health, according to a King’s College London study.
Researchers from the university’s Department of Nutrition find that greater diversity in plant food consumption is linked to better markers of cardiometabolic health, including improved cholesterol levels, blood sugar control, overall diet quality, and intake of key nutrients such as fiber, vitamins, and minerals.
The university notes that this is the first study to examine the number and types of plant foods people consume and how that diversity relates to key health indicators.
“Current dietary guidance in the UK often emphasises quantity, such as ‘five-a-day’ for fruit and vegetables. Our findings suggest that dietary variety, across all plant-based food groups, may be just as important for improving diet quality and lowering the risk of cardiometabolic diseases,” says Dr. Eirini Dimidi, senior lecturer in Nutritional Sciences at King’s College London and senior author of the study.
The analysis, published in Clinical Nutrition, looked at data from over 670 adults participating in the UK National Diet and Nutrition Survey in 2016–2017, 97% of whom followed an omnivorous diet.
Plant-based diversity
Participants were categorized based on how many different plant-based foods they consumed daily: the low diversity group consumed about 5.5 types per day, the moderate group 8.1 types, and the high diversity group around 11 types.
The study found significant links between lifestyle profiles and dietary variety. Only 6% of people in the high-diversity group smoked, compared with 30% in the low-diversity group. Individuals with more diverse plant-based diets were also more likely to meet fiber recommendations and had healthier blood lipid profiles overall.
They also ate more total sugar, likely due to higher fruit and fruit juice consumption. While acknowledging that excess sugar can negatively impact health, the researchers say that fruits also provide fiber and antioxidants, which may mitigate some effects.
“Vegetables were the largest contributors (21%) to diversity, followed by plant-based fats and oils (18.8%), and fruit (17%). Categories such as nuts, seeds, legumes, despite their established nutritional benefits, contributed minimally to total intake,” says Dimidi.
“While higher diversity was associated with better nutrient adequacy overall, key shortfalls remained even among those with the most diverse plant-based diets, particularly for fiber and several micronutrients important for maintaining a strong immune system and healthy bones and tissues.”
“In addition to fruits and vegetables, legumes, nuts, seeds, herbs, and spices are great plant-based food sources that can help us to introduce more plant diversity into our diets,” she continues.
The researchers conclude that promoting a more diverse intake of plant-based foods, especially those currently under-consumed, could be an effective public health strategy for improving diet quality in the UK population.