In a recent study published in JAMA network open Researchers used a long-term, large-cohort study design to assess the effects of ultra-processed foods (UPFs) on mental health, according to the Journal.
study: Consumption of ultra-processed foods and risk of depression. Image credits: daisy daisy/Shutterstock.com
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Their results suggest that UPF, especially artificially sweetened beverages, significantly increases the risk of depression in midlife Hispanic women.
Reducing UPF intake by at least three servings per day partially saved study participants from the risk of depression. However, additional studies will be needed to validate this finding and elucidate the extent of risk reduction.
Ultra-processed foods and health
As the old saying “you are what you eat” suggests, diet is one of the most important modifiable treatments available to individuals to improve their health and well-being.
Unfortunately, there has been an alarming trend in recent decades away from fresh and minimally processed foods to “fast food,” highly modified meals that taste appealing but have low nutritional value. This is a transition. Recent evidence suggests that consumption of these foods can have negative effects not only on physical health but also on mental health.
“Ultra-processed foods” (UPFs) are a relatively new food category in the NOVA classification system. These foods are made from extracts of fats, starches, added sugars, and hydrogenated fats.
They may also contain additives such as artificial colors, flavors, and stabilizers. These foods include frozen foods, soft drinks, hot dogs and cold cuts, fast food, packaged cookies, cakes, and salty snacks.
A growing number of studies point to UPF as a direct cause of human diseases such as irritable bowel syndrome, obesity and overweight, decreased immune response, and cancer. However, research on the effects on mental health is still lacking.
Although there are only a few studies available in this area, most suffer from a lack of longitudinal data, small cohort sizes, or limited ability to overcome potential confounders of observational data.
The global prevalence of mental health illnesses makes it important to identify risks, especially when they are behavioral and easily modifiable.
About research
In this study, researchers used a sizable cohort of women from the Nurses’ Health Study II, a joint sample group of the Harvard T.H. Chan School of Public Health and Brigham and Women’s Hospital.
This longitudinal study was conducted from 2003 to 2017, with follow-up surveys every four years. The sample cohort consisted of 31,712 people (mean 52) aged 42 to 62, all of whom had no symptoms of clinical depression at the start of the study.
The methodology of this study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guidelines.
Data collection includes the use of a validated food frequency questionnaire (FFQ) with clinical mental health assessments at study entry and every 4 years thereafter.
UPF intake was quantified by first defining UPF according to the NOVA classification of food categories. The UPF diet was further broken down into its components, each of which was analyzed separately, to gain additional model evaluation power.
These include ultra-processed grain foods, convenience foods, sweet snacks, fats and sauces, savory snacks, ultra-processed dairy products, artificial sweeteners, processed meats, and beverages.
“We used two definitions of depression: (1) a strict definition that required clinician self-reported depression and regular antidepressant use, and (2) a clinical diagnosis and / or a broad definition that requires the use of antidepressants.”
Cox proportional hazards models were used to calculate hazard ratios (HR) and class intervals (95% CI) for depression using UPF consumption quintiles.
Avoid model bias and include known and Income, marital status, and sleep quality were adjusted during model testing to control for suspected risk factors for depression.
Comorbidities of depression, such as diabetes, hypertension, and dyslipidemia, were also considered in the analysis.
To determine whether the consequences of UPF intake were reversible, the researchers ultimately studied individuals who reduced their UPF intake over four consecutive years of follow-up and those whose consumption remained relatively stable. We analyzed the individuals that were present.
research result
The results of this study showed that increased UPF intake was associated with increased risk of depression, as shown by hazard ratios of 1.49 (2,122 people) and 1.34 (4,840 people) for the strict and broad definitions of UPF, respectively. has established a direct relationship.
People with higher UPF consumption also have an increased prevalence of other unhealthy behaviors, such as smoking, lower physical activity levels, higher BMI, comorbidities of depression, and especially diabetes, hypertension, and dyslipidemia. I showed it.
Adjusting the model for potential confounding variables did not significantly change the study results. Surprisingly, no direct association was found between age, BMI, physical activity, or smoking and increased risk of depression.
“In a 4-year lag analysis, the association did not change significantly (strict definition: HR, 1.32; 95% CI, 1.13-1.54; P < 0.001), ruling out reverse causation."
UPF component analysis revealed that artificially sweetened beverages and sweeteners were directly associated with the risk of depression, but the associations with other components were not significant.
Finally, an exploratory analysis showed that reducing UPF intake by three servings per day partially rescued participants from the risk of depression compared to participants who maintained relatively stable UPF intake patterns. It became clear that it was possible.
“These findings suggest that higher UPF intake, particularly intake of artificial sweeteners and artificially sweetened beverages, is associated with increased risk of depression. Although the relevant mechanism is unknown, recent experimental data suggest that artificial sweeteners induce purinergic transmission in the brain, which may be involved in the pathogenesis of depression. ”