Research

Energy balance

Obesity and excess caloric intake lead to immune dysfunction by causing leptin resistance and downregulating immune responsiveness, increasing susceptibility to infections.

Maintaining a healthy weight is crucial for immune function. Obesity is linked to reduced white blood cell activity and increased inflammation. While weight loss is beneficial, understand that the biological changes (like leptin resistance) take time to reverse, and immune health is also influenced by the quality of fats and sugars you consume.

GoodSupportsHIGH confidence
Obese individuals have fewer white blood cells to fight infection and those cells they do possess have reduced phagocytosis capability... One possible mechanism for obesity’s harmful effects on the immune system could be the increased levels of leptin in the blood... patients with obesity may, overtime, down-regulate the immune activation attributable to leptin.
Ian A. Myles · Nutrition Journal · 2014

Why this rating

The paper cites multiple human studies showing reduced white blood cell counts and phagocytosis in obese individuals.

Source

Fast food fever: reviewing the impacts of the Western diet on immunity

Ian A. Myles · Nutrition Journal · 2014

DOI 10.1186/1475-2891-13-61

narrative_reviewCited 379×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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