Peer Reviewed Open Access Research Journal
International Journal of Medical Laboratory Research (IJMLR)

DOI: 10.35503
Review Article
Abstract
HOW HEALTHY EATING BOOSTS IMMUNITY AND JUNK FOOD WEAKENS IT - A COMPREHENSIVE REVIEW
Fayisa Nargees CTK, Bharathi B, Deepa C Philip
ABSTRACT: Nutrition plays a crucial role in modulating immune responses, thereby affecting vulnerability to infections, inflammation, and chronic diseases. Essential vitamins, including A, B-complex (B6, B12, Folate), C, D, and E, contribute to immune regulation by enhancing cellular defense, antioxidant mechanisms, and immune cell production. Deficiency in these nutrients weakens immune function, increasing susceptibility to infections and inflammatory conditions. A diet rich in fiber promotes gut microbiome health, which is closely associated with immune regulation. Fiber aids in gut barrier function, fosters the growth of beneficial bacteria, and helps mitigate inflammation. Conversely, excessive intake of processed and fast foods—high in refined sugars, unhealthy fats, and sodium—has been linked to metabolic imbalances, heightened inflammation, and a weakened immune defense. Studies indicate that the overconsumption of fast food contributes to obesity, cardiovascular disease, diabetes, and mental health disorders such as depression. Additionally, diets high in salt and trans fats can exacerbate hypertension and systemic inflammation, leading to long-term health issues. Scientific research underscores the relationship between dietary habits and disease prevention, emphasizing the benefits of consuming nutrient-dense foods. The Mediterranean diet, characterized by whole foods such as fruits, vegetables, whole grains, healthy fats, and lean proteins, is associated with reduced inflammation and enhanced immune function. In contrast, the Western diet, which is dominated by processed foods and sugary drinks, has been linked to increased oxidative stress and a higher prevalence of chronic diseases. Emerging evidence suggests that dietary components also influence mental well-being, with specific nutrients playing a role in reducing the risk of mood disorders. Given the significant connection between nutrition and immune function, public health strategies should prioritize the promotion of healthier eating patterns. Encouraging a transition from processed foods to whole, nutrient-rich options can strengthen immune resilience, lower the risk of chronic diseases, and improve overall well-being. Future research should focus on personalized nutrition approaches tailored to individual dietary needs and genetic predispositions.
KEYWORDS: Nutrition, Immune Function, Inflammation, Micronutrients, Chronic Diseases, Dietary Patterns
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To cite this article:
Fayisa Nargees CTK, Bharathi B, Deepa C Philip. How healthy eating boosts immunity and junk food weakens it - a comprehensive review. Int. J. Med. Lab. Res. 2025;10,2:1-5. http://doi.org/10.35503/IJMLR.2025.10201