What people eat every day may be shaping their mental health more than many realise. New research suggests that diets high in sugar are consistently linked with higher levels of anxiety and depression across different age groups and countries. The findings were published in Obesity Reviews.
The findings come from a large systematic review that examined evidence from children, teenagers, and adults worldwide. Rather than focusing on one population or lifestyle, the review pulled together results from dozens of studies to understand whether sugar consumption is associated with poorer mental health outcomes.
Across the evidence, people who regularly consumed large amounts of sugar were more likely to report symptoms of depression, anxiety, or both. This pattern appeared in school age children, adolescents, working age adults, and older populations, suggesting the association is not limited to one stage of life.
Sugar intake was most often measured through sugar sweetened beverages such as fizzy drinks, sweetened teas, fruit flavoured drinks, and energy drinks. These products are widely consumed and often marketed aggressively, particularly to young people. Many of the studies reviewed found that frequent consumption was linked to worse mood, emotional distress, or psychological symptoms over time.
Teenagers appeared especially vulnerable. Several large studies reported that adolescents who consumed sugary drinks daily were more likely to experience depressive symptoms compared with peers who consumed them less often. Some research also linked higher sugar intake with anxiety symptoms, including restlessness and persistent worry.
Among adults, similar trends emerged. Long term studies following people for years found that those with higher sugar consumption were more likely to develop depressive symptoms later on. While not every study showed the same strength of association, the overall direction of evidence pointed towards a consistent relationship.
Researchers caution that the findings do not prove sugar directly causes anxiety or depression. Mental health is influenced by many factors, including stress, sleep, physical activity, and social circumstances. However, sugar intake appears to act as a modifiable risk factor that may contribute to poorer mental well being alongside other pressures.
There are several biological explanations that may help explain the link. High sugar consumption can affect blood sugar regulation, inflammation, and stress hormones, all of which play a role in mood regulation. Sugary foods and drinks may also be used as a coping response during stress, reinforcing unhealthy patterns over time.
Importantly, the review also noted that diets richer in whole foods such as fruits were often associated with better mental health outcomes. This suggests that overall diet quality matters, not just individual nutrients in isolation.
Public health experts say the findings add weight to existing advice to reduce sugar intake. Policies such as clearer food labelling, limits on sugary drink marketing, and sugar taxes may not only benefit physical health but also support mental health at a population level.