Influence of Acute Nut Intake on the Effects of High Saturated Fat Meals in Obese Diabetic Women

Obesity is a multifactorial disease in which excess body fat accumulation leads to negative health effects. It is considered a global public health problem, primarily due to its association with an increased risk of developing other non-communicable chronic diseases (NCDs). In Brazil, it is estimated that one quarter of the population is obese, making it an important risk factor for pathological aging.

The primary cause of obesity is the energy imbalance between calories consumed and expended, and its high prevalence is associated with physical inactivity and sedentary behavior. A balanced diet, consisting of natural and minimally processed foods, is known to be essential for weight control. However, in the current scenario, there has been a significant increase in the consumption of ultra-processed foods and a decrease in the intake of natural and minimally processed foods, resulting in a major impact on the prevalence of obesity.

Obesity is one of the most relevant risk factors for type 2 diabetes, a disease that is increasingly prevalent worldwide and is considered one of the health emergencies of the 21st century. Diabetes impacts morbidity and mortality and is a major risk factor for stroke, kidney dysfunction, cardiovascular diseases, vision loss, and neuropathy. Non-pharmacological strategies to control diabetes typically include nutritional intervention, regular physical activity, smoking cessation, and maintenance of a healthy body weight.

Acute intake of macronutrients can induce adverse responses even in healthy individuals, which may lead to chronic effects over time. In this context, the intake of a high saturated fat meal (HSFM) plays an important role, as chronic consumption of a HSFM is known to contribute to the development of obesity, type 2 diabetes, cancer, and cardiovascular diseases, as well as exacerbate chronic inflammation induced by insulin resistance and excess weight. Additionally, studies show that HSFM can also induce metabolic endotoxemia and modulate profiles of circulating microRNAs. MicroRNAs are non-coding RNA molecules about 22 nucleotides long that regulate gene expression at the post-transcriptional level by degrading mRNA or inhibiting the translation of target genes. Thus, microRNAs may contribute to the adverse effects of HSFM.

Given the detrimental health impacts of HSFM, studies have been conducted with acute supplementation of foods with anti-inflammatory and antioxidant properties, such as orange juice and green tea, in order to minimize the negative effects of unhealthy diets. A study conducted by our research group showed that acute supplementation of green tea inhibited the expression of 62 microRNAs induced by HSFM intake. Bioinformatics analysis revealed that these microRNAs regulated genes associated with TGF-beta, CARM1, RSK, and BMP pathways. Identifying these miRNAs and their molecular pathways can enhance understanding of the benefits of dietary compounds in health and disease.