Sugar is a direct source of sweetness that not only enhances the flavor of food but also serves as a source of energy for the body. Sugar is used in everyday life to give us a "sweet" feeling, whether it's in candy, cake, or cola.

Sugar consumption is quickly increasing as material living standards rise, which not only leads to an increase in obesity rates, but also increases various health hazards, including diabetes, atherosclerosis, hyperlipidemia, and hypertension, as well as speeding aging and even promoting cancer.

Adolescents also consume more sugar and have a higher rate of psychiatric illnesses than other age groups. Patients with psychiatric problems consume two times the amount of sugar consumed by healthy people their age, and schizophrenics who take more sucrose have more severe symptoms. This emphasizes the link between excessive sugar consumption and psychiatric illnesses.

Recently, researchers at the Institute of Medical Science, University of Tokyo, Japan, published a paper in Science Advancestitled: High-sucrose diets contribute to brain angiopathy with impaired glucose uptake and psychosis-related higher brain dysfunctions in mice, demonstrating that a diet high in sugar during adolescence induced behavioral phenotypes associated with psychiatric disorders, including ADHD, memory loss, and sensory retardation.

In addition, in mice, a high-sugar diet can lead to cerebrovascular disease (, impaired glucose uptake, and higher brain dysfunction associated with psychiatric disorders, and aspirin administration can prevent these high-sugar diet-induced abnormal behavioral phenotypes.

Previously, some studies have suggested that a high-sugar diet may also lead to mental illness. Notably, adolescents have a higher daily sugar intake than other age groups, however, there is little research on the effects of high sugar intake during adolescence on future mental health.

The onset of most chronic psychiatric disorders, such as schizophrenia and bipolar disorder, is attributed to a complex interplay of multiple genetic and environmental risk factors, and most onset occurs before the age of 30. In this study, the team first noted that patients with schizophrenia and bipolar disorder consume about twice as much sugar as healthy people of the same age, and that the more sugar consumed by patients with schizophrenia, the more severe their symptoms.

To do this, the researchers fed the young mice two diets, a normal diet and a high-sugar diet whose main carbohydrate was starch or sucrose. After 50 days of feeding, the researchers subjected these mice to eight different behavioral tests, including motor activity, sound startle response, object location tests, and maze behavior.

The team found that sucrose-fed mice showed significant reductions in object location tests, working memory, and maze behavior. This result suggests that a diet high in sucrose can induce a mental illness phenotype in mice.

Advanced glycation end products (AGEs) have been demonstrated in studies to cause inflammation and oxidative stress in various tissues, resulting in a positive feedback loop that increases AGEs. Patients with psychiatric problems have a profile of enhanced pro-inflammatory cytokines and increased oxidative stress, according to data.

Glyoxalase I (GLO1) is a zinc metalloenzyme that protects cells from the toxic effects of AGEs. Interestingly, the decreased expression of GLO1 in patients with schizophrenia and bipolar disorder, combined with increased sugar intake, may be responsible for the increased inflammation and oxidative stress observed in these disorders.

Based on this, the research team constructed GLO1 knockout heterozygous mice to verify whether a high sugar diet causes mental illness. The researchers found that a high-sugar diet induced microcapillary damage and reduced brain glucose uptake in GLO1 knockout mice. Meanwhile, the researchers found similar vascular damage in brain samples from schizophrenia and bipolar disorder.

Aspirin, a long-acting anti-inflammatory medicine, was also found to be useful in preventing vasculopathy, improving glucose absorption in the brain, and reducing aberrant behavioral phenotypes. These findings imply that a high-sugar diet may interfere with the brain's glucose uptake via GLO1-related metabolic pathways, resulting in microcapillary damage and brain malfunction, and ultimately mental disease.

In conclusion, this study discovered that a high-sugar diet, particularly one high in sucrose, may be one of the factors contributing to adolescents' high rates of mental illness. This finding was explained by the fact that a high-sugar diet causes brain microcapillary damage and dysfunction as a result of metabolic stress, whereas chronic anti-inflammatory medicines like aspirin may protect against the harm induced by a high-sugar diet.

Author's Bio: