Most of the aging theories are monistic in nature, they omit numerous key factors of senescence during the process of model creation. There are two main categories of these theories: program theories and error (mutation) ones. Program theories imply the existence of internal or external programs that determine the aging process ab ovo. The error theories involve explicit or implicit the idea that aging would not happen without the destructive factors that cause errors, mutations, regulation disorders, and in turn these processes finally lead to disfunctions and senescence. The aim of this paper is to indicate that aging may be multifactorial and the process of senescence may be determined by the information level of the organization. This level itself changes during senescence (including the information level of the genom that also alters by time because of, e.g. its 'fluid' character). According to this approach the aging process is determined by the sum effects of internal (e.g. genom) and external (material, energy, information) factors, although there are some elements that bear more importance than others. Subsequently, the maximal life-span is probably determined by the principle of the weakest element of the chain. Because of the high complexity of the human body where different information systems superpose each other, the cooperation of the elements (counter-effects, regulation) have the same determining importance as the information level of the unit parts (cells) have. The further aim of this paper is to show that the roots of certain diseases (e.g. cancer) could firmly be linked to the aging process itself. This interpretation offers two ways of influencing the process of senescence. It could be influenced by maintaining the information level of the organism via optimization or by changing (elevating) this level. All the factors that help to prevent the decrease of the information level of the organism could act against aging and certain diseases, and vice versa: the factors which deteriorate the state of the information system could contribute to the acceleration of the aging process.