In an evolutionary model, health and disease are regarded as successful and respectively failed adaptation to the demands of the environment. The social factors are critical for a successful adaptation, while emotions are means of both signaling the organism’s state and of adapting the physiological responses to environmental challenges. Hence the importance of a biopsychosocial model of health and disease. Psychoemotional distress generates and/or amplifies somatic symptoms. Somatization may be viewed as an altered cognitive process, inclining the individual to an augmented perception of bodily sensations and to an increased degree of complexity in reporting negative experiences (hence the greater cognitive effort allocated thereto). Somatosensory amplification and alexithymia are key elements in this process. The brain’s right hemisphere is more involved in the generation of emotionally conditioned somatization symptoms. Somatic symptoms have various psychological and social functions and are strongly influenced by the particular belief system of the individual. Inappropriately perceiving the environment as an aggressor and excessively responding to it (by activating the cytokine system in correlation with the arousal of the psychic, nervous, and endocrine systems) may be a key element in the altered cognition conducive to ill health.