Can Eating Too Much Sugar Lead to Depression?

"For years, researchers have suspected that excess sugar in food and drinks can cause depression. One reason it was suspected was because people with diabetes have an increased incidence of depression that is beyond what would be expected only from the challenges of dealing with a chronic illness. Having diabetes is associated with two to three times the rate of depression compared to the general population."

"Recent studies have demonstrated that excess sugar can cause depression in non-diabetics. For example, data from the National Health and Nutrition Examination Survey showed that a 100 mg per day increase in dietary sugar correlated with a 28 percent increase in depression (Zhang, 2024). Another study showed that artificially sweetened beverages and not just excess sugar were associated with an increased incidence of depression (Xie, 2015). This research supports prior data about the role of artificial sweeteners in contributing to depression."

"How does excess sugar intake increase the risk of depression? One major way is that excess sugar affects the function of the gut microbiome. A microbiome is a collection of trillions of bacteria, viruses, and fungi that live symbiotically both in and on the body. These microbes are found on the skin and in the GI tract ("the gut"), mouth, lungs, airways, and the genitourinary tract, including the vagina."

Excess dietary sugar and some artificial sweeteners increase risk of depression and anxiety. People with diabetes show two to three times higher depression rates, partly linked to rapid blood sugar spikes and crashes that impair mood and cognition. Large population data indicate each 100 mg/day sugar increase correlates with substantially higher depression incidence, and artificially sweetened beverages show similar associations. Excess sugar alters gut microbiome function, promoting systemic inflammation and disrupting production of key neurotransmitters such as serotonin and dopamine, which increases vulnerability to mood disorders.

Read at Psychology Today