Although you can use cotton for a number of purposes, it is a fact that you cannot eat cotton plants. The seed of this plant is really poisonous for the human race and can cause serious diseases and ailments. Therefore, you can use cotton for a number of purposes like in mattresses, in clothing, for cleaning purposes, in coffee machines but you cannot eat the cotton plant as it is really poisonous. But for the time being, many scientists are working to make genetically engineered varieties of cotton that are safe for consumption.