TLR4 and metabolic syndrome: A similar finding of no association between TLR4 Asp299Gly and metabolic syndrome or diabetes was observed by Illig et al. [11] Research has shown that obesity affects the mechanics and physiology of the respiratory system and people with higher BMI [18,23] and waist circumference [17] are more likely to have lower values for FEV1, FVC and higher values for FEV1/FVC ratio.