How do you define health in a networked age? The Global Health Observatory, the World Health Organisation's data-gathering centre for over 194 countries, has 33 themes ranging from HIV/AIDs, water and sanitation to road safety and mental health.

I would like to add another for the fully connected era: social health.

We are in the middle of what sociologists Lee Rainie and Barry Wellman call the 'triple revolution' of the internet, social media, and mobile. I believe that there is an emerging, measurable malaise linked directly to the speed and scale of modern connectedness which impacts on many of the old metrics of illness and wellness, as well as creating some new ones too.

Take stress. We know that global stress levels are rising: the market in antidepressants is set to rise to $16.8 billion by 2020 - the same year, incidentally, that the number of connected devices in circulation will reach 50 billion.

Days taken out of work attributed to stress are also rising: the European Agency for Safety and Health at Work estimates that between 50-60% of working days lost annually are due to stress.

I agree with the historian Yuval Noah Harari, who cites in his magisterial book Sapiens: A Brief History of Humankind the way that the impact of sudden modernity on farming communities had "revved up the treadmill of life to ten times its former speed and made our days more anxious and agitated".

Our neolithic forbears, domesticating einkorn wheat in a world with fewer than five million people could not have forseen an era where the founder of a single social network, Mark Zuckerberg, noted that 1 billion people were on Facebook at the same time on a single August day in 2016. He saw this as "just the beginning of connecting the whole world'.

My problem with connectedness is that it has happened so suddenly, so ruthlessly, that we have not begun to process what impact this has on our behaviours, our communication systems, and the tension of a human being still operating on a mere 168 available hours in a week end-to-end (including sleep), operating cheek-by-jowl with what is de facto a new species: technology. It is 70 years since the World Health Organisation was created and its essential definition of health has remained unchanged as 'a state of physical, mental and social wellbeing, and not merely the absence of disease or infirmity'.

This is especially interesting given that what was meant by 'social wellbeing' last century did not - could not - factor in the computer. Yet modern society, which has only been organised on networked technology for a mere one hundred and fifty years (arguably since the laying of the first cables of connectedness underwater between Newfoundland and Ireland in 1857) is now truly embedded in them.

We cannot disentangle. So we need new narratives, new metrics, and above all, new practices and behaviours.

If I was adding 'Social Health' to the current WHO definition, I might define it like this: "Social Health means balancing face-to-face and electronic connections in a way that manages flows of knowledge, networks and time. Those with good Social Health know who and what to connect with, as well as the value of disconnection as a way of staying healthy. Social Health is a mindset and a behaviour that applies equally to individuals and organisations".

Because the world's language is reducing to Twitter-length, let's really shorten it:

"Social Health is who, what and when you know. Those with Social Health balance face-to-face and technology, and know where to find the off switch".

I am confident that the incoming Director General of the WHO, Dr Tedros Adhanom Ghebreyesus, and his top team including Dr Nata Menabde, Executive Director, will look to build on the concept of 'social wellbeing' to incorporate Social Health and thus lead the way globally for much-needed policy changes in the way in which we regard health around connectedness.