Ruut Veenhoven is a sociology professor at the University of Rotterdam and a member of the advisory board for the Happiness Institute. He has collected and analyzed research in the field of happiness in order to compile the “World Database of Happiness.” In this interview, Veenhoven reveals what factors can lead to greater life satisfaction – and how happiness and health are related.

Professor Veenhoven, according to your database, which country has the happiest people?

People are particularly cheerful in Denmark, where we have found the highest numbers in long-term life satisfaction. On a scale of one to ten, the average level of happiness there is 8.3. In comparison, Zimbabwe is only 3.4 points and in Germany the average is 7.1.

Denmark is a comparatively rich country – does this mean happiness is related to wealth?

Wealth is only one of many factors. One of the most decisive influences, beyond the financial, is the quality of a nation’s society as a whole. Things that contribute to a strong society, for example, are freedom of expression, a sound legal system, and gender equality. These are all factors that contribute to the happiness of the population as a whole.

Are happy people also healthier?

Yes, and that’s why they live longer, too. There is now a vast amount of empirical evidence on this. I have analysed 30 different studies on the effect of happiness on health, and it shows: happy, fun-loving people recover quicker from illness and live longer lives. Especially in predominantly healthy populations, the effect of a positive attitude on life expectancy is roughly the same as not smoking.

So how does happiness influence physical health?

Happy people tend to pay more attention to their health. They are also generally less stressed, because they usually participate more actively in social life and have stronger social connections. Being less stressed means that they are also less prone to infection.

Which study on happiness and health has impressed you the most?

The psychologist Sheldon Cohen, along with his research group at Carnegie Mellon University in Pittsburgh, studied the mental stress levels of about 400 students during exam time and then administered nasal drops containing the cold virus. Students who were stressed and unhappy were more than three times more likely to catch a cold, in comparison to those who remained relaxed and optimistic. So a positive outlook on life can help in arming yourself against future sickness!