Illuminating insights: Exploring the effect of 16/8 intermittent fasting on serum cytokine levels in overweight adults

The immune system's pivotal role extends to numerous diseases, and maintaining a balance between dietary and consumed energy is vital for preventing chronic illnesses and increasing life expectancy. Intermittent fasting (IF), a dietary approach typically implemented through time restrictions, exerts positive effects on the immune system and shows promising outcomes in managing various diseases. To evaluate the effectiveness of IF on the immune system with a wide cytokine panel. A total of 21 volunteers with body mass index (BMI) between 25 and 30 were included in the study. Fasting was applied for 16 h in a day to the volunteers, and they were free to consume food for the rest of the day. The weight, BMI, interleukin (IL)-1β, interferon (IFN)-α2, IFN-γ, tumor necrosis factor (TNF)-α, monocyte chemoattractant protein (MCP)-1, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IL-18, IL-23, and IL-33 values were measured using flow cytometry and compared before and after 21 days follow-up. The mean age of study participants was 37.76 ±8.06 years and weight loss of the volunteers was 3.35 percentile compared to the values obtained before fasting. The pro-inflammatory cytokines decreased, while anti-inflammatory cytokines increased after fasting; there was a significant difference in TNF-α, MCP-1, IL-6, IL-8, and IL-33 values. Also, IL-1β, IL-8 and IL-12p70 had moderately positive, IL-33 had strongly negative, and IL-10 had moderately negative correlation with the BMI change over time. Intermittent fasting has positive effects on obesity-induced inflammation and promotes decrease in proinflammatory cytokines and increase in IL-33 values, which is known to have a protective effect on fat-associated inflammation.