At the end of 2025, actor Dick Van Dyke reached the age of 100. He released a book titled 100 Rules for Living to 100, describing his approach to a long and content life. He stated that he never starts the day in a negative frame of mind. Research discussed in 2025 indicated that an optimistic outlook is associated with extended lifespan. A study of nuns from the 1930s showed that those expressing more positive emotions lived about ten years longer on average. A 2019 UK analysis of large groups found that higher optimism correlated with up to 15 percent greater longevity and higher chances of reaching age 85 or more. Factors such as strong relationships and a sense of purpose, often tied to positivity, were linked to better health outcomes in long-running studies. One major project that began in 1938 identified satisfying social connections as a key predictor of health at advanced ages. Experts estimate that reaching 90 depends roughly 30 percent on genetics and 70 percent on lifestyle choices. Similar patterns appeared in research on centenarians, where a sense of purpose was connected to lower rates of illness and impairment. David Attenborough, who also turned 100, remained active and engaged in his work. Van Dyke has described old age as partly a matter of attitude and partly chance.
