Associations between nutrition knowledge and obesity-related attitudes and physical activity among young adults from Kenya, South Africa, and the United Kingdom

Abstract

Objective: This study’s aim was to test associations between nutrition knowledge and obesity-related attitudes and physical activity (PA) among 3000 18–35-year-old men and women from Kenya, South Africa (SA), and the United Kingdom (UK).
Methods: A cross-sectional online survey was conducted in April 2022. To estimate nutrition knowledge, dietary recommendation knowledge score was computed using the standard General Nutrition Knowledge questionnaire. Obesityrelated attitudes were from the British Social Attitudes Survey. Self-reported days of vigorous and moderate PAs and walking were used. Ordinal logistic regression was employed to test all associations, while adjusting for age group, gender and a household asset score. Using simple mediation, testing was also done to ascertain whether obesity-related attitudes mediated associations between nutrition knowledge and PA.
Results: Consistently, better nutrition knowledge was associated with disagreeing that ‘There is no reason to worry about obesity’ (ORs ≥ 1.09), but lower odds of being against ‘Providing free weight management courses’ and ‘Creating/improving cycle paths and pavements to encourage PA’ (ORs ≤ 0.90). Better nutrition knowledge was also associated with higher vigorous PA in SA (OR = 1.09), and moderate PA (OR = 1.04) and walking (OR = 1.12) in the UK. In the combined sample, associations of nutrition knowledge with vigorous PA were fully mediated by believing that ‘Obesity results from not exercising enough’ (11.1% mediated). Likewise, associations of nutrition knowledge with moderate PA were fully mediated by attitude towards ‘Creating or improving cycle paths and pavements to encourage PA’ in the UK (38.9% mediated).
Conclusions: Nutrition knowledge is associated with obesity-related attitudes and PA among young adults, but some relationships are country-specific. Interventions based on findings from high-income countries should be evaluated before being implemented in low-resource settings.

Keywords: nutrition knowledge, obesity attitudes, physical activity, multi-country, young adults, South Africa, Kenya, United Kingdom