This book provides a comprehensive and state-of-the-art overview of effect of nutrition on genes.Gingivitis and periodontitis initiated by sub gingival plaque indirectly depends on innate resistance of the periodontal tissues to infection .Host based risk factors such as genetic background of an individual, socio-economic status, smoking and dietary habits have all been suggested to alter the innate immune response of the host to periodontal disease. Nutrition is important to maintain the balance between microbial challenge and the host response as it has been implicated in a number of inflammatory diseases and conditions.