The influence of sugar intake on depressive mood and the mediating effect of body dissatisfaction

Abstract

Sugar consumption has increased over the past years and has surpassed the recommended amount. This has many negative consequences such as weight gain and chronic diseases, but it can also impact mental health. Studies found that sugar can increase depressive mood. These studies however only studied specific sugary products that are generally known to be unhealthy and high in sugar. By only focusing on these products, these studies could not conclude that sugar intake in general increases depressive mood, but only that the certain obviously sugary products they studied increase depressive mood. To answer this question, this study therefore studied if total sugar intake, both from obviously sugary products but also from products that seem healthy but still contain a high amount of sugar, called hidden sugars, also lead to depressive mood. It was expected that intake of total sugar, sugars from obviously sugary products and hidden sugars all increase depressive mood. It was also expected that body dissatisfaction would mediate this effect, since studies found that consuming sugary products can decrease body satisfaction, and low body satisfaction can cause depression. This effect is more prevalent for obviously sugary products so it was expected that the influence of sugar on depression would be larger for these products than for products with hidden sugar. The hypotheses were tested among N = 292 participants. Sugar intake was measured with a Food Frequency Questionnaire, for depression the Hospital Anxiety and Depression Scale was used and for body satisfaction the Body Shape Questionnaire was used. Three multiple hierarchical regression analyses showed that intake of total sugar, sugar from obviously sugary products and hidden sugars all did not significantly predict depressive mood. Body satisfaction was not found to be a significant mediator in any of these analyses. The results found in this study were contrary to the expectations and preceding studies. This might be due to how this study measured sugar intake and depression. Since this study did not find that sugar could increase depressive mood, no recommendations for people to reduce their sugar intake to improve their mood can be made. However, high sugar intake has many negative consequences that in the long term can also negatively impact mood. It is therefore still advised that people reduce their sugar intake. This can be done on policy level by providing knowledge and implementing a sugar tax. For future studies, it is suggested to perform a longitudinal study to look into the causal relationship of sugar intake and depressive feelings and also to look more into the difference between the influence of sugars from obviously sugary products and hidden sugars on depression. In these future studies, it is advised to let participants track their food intake and depressive feelings by use of a diary.