Final answer:
The WHO's definition of health established in 1948 has not been formally changed in 1986. It encompasses physical, mental, and social well-being. Discussions on health have evolved, but the official definition remains the same.
Step-by-step explanation:
The definition of health according to the World Health Organization (WHO) as established in 1948 has not officially changed in 1986. The original definition by the WHO describes health as "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity." While there have been discussions and developments in understanding health since that time, there is no evidence of a formal change in the official WHO definition of health in 1986. The WHO continues to advocate for a holistic approach to health, highlighting the importance of lifestyle and diet, as evidenced by the interest in diets such as the Mediterranean diet and the paleo diet, which are linked to lower rates of chronic illnesses and longer life spans.