It's the reason why spending time on Facebook makes us feel sad and lonely. Why expensive name-brand medicines provide better pain relief than the generic stuff, even if they share the same ingredients. And why a hospital room with a good view speeds up recovery from surgery.

The truth is, the way we think about ourselves and the world around us dramatically impacts our happiness, health, how fast or slow we age, and even how long we live. In fact, people with a positive mindset about ageing live on average 7.5 years longer than those without.

That might sound alarming to those of us who struggle to see the bright side, but the good news is we can make surprisingly simple changes or small shifts to how we think, feel, and act that will really pay off.

In The Positive Shift: Mastering Mindset to Improve Happiness, Health, and Longevity, Dr. Catherine Sanderson breaks down the science of thought and shows how our mindset - or thought pattern - exerts a substantial influence on our psychological and physical health. Most important, this book demonstrates how, no matter what our natural tendency, with practice we can make minor tweaks in our mindset that will improve the quality - and longevity - of our life.