LEP and Alzheimer disease: It remains to be established whether these positive associations are causal, e.g., linked to inflammation of adipokines (molecules synthesised and secreted by adipose tissue), such as leptin and adiponectins, or related to dietary factors, that may encourage the development of AD through oxidative stress, since diets that exclude antioxidant foods, such as fruits and vegetables, are related to an increase in obesity and AD.