The social determinants of health are all the non-medical factors that influence health outcomes. But what are these factors and how are they related to health inequalities?
Social and economic factors, our physical environment and the ability of our health services to respond all contribute greatly to our health.
These factors greatly influence people’s health, far more than any individual lifestyle choices such as alcohol consumption, diet, smoking or any other factor that people can control. In addition to this, these individual health behaviours themselves are also shaped by the places and environments in which we live.
People living in poorer communities can be subject to a ‘double effect’: already living in overall worse social, economic and environmental conditions, they can face challenges and barriers when making individual health choices too – for example food insecurity or lack of safe outdoor space for walking and exercise.
These external social, economic and environmental factors and their impacts, both on health and health behaviours, are collectively referred to as the social determinants of health.
How do the social determinants of health affect health inequalities?
The social determinants of health are the conditions in which people are born, grow, work, live, and age, and the wider set of forces and systems shaping the conditions of daily life. These forces and systems include economic policies and systems, social and cultural factors, environmental effects and political systems.
Because these factors affect every single area of life, they are different for everyone and every community. Existing widespread inequalities in areas such as income, housing, and physical environment then interact together to produce health inequalities.
For example, someone living in housing with a mould problem is more likely to develop lung problems, or someone who lives in poverty may have poorer health due to not being able to afford to eat regular, healthy meals. And these factors can all interact together to produce the widening health inequalities we see between our poorest and our more affluent communities.
This model describes the ways in which the determinants interact at the macro to micro level with inequality as the consequence.
How can we track and measure health inequalities?
There are two key measures we use when we talk about health inequalities: life expectancy (a measure of how long we can expect to live) and healthy life expectancy (how many of those years are expected to be in good health). Access links to recent research, data and other relevant resources.
Statistics on life expectancy published by National Records of Scotland (NRS) in 2024 showed that in 2021-2023 life expectancy was 80.9 years for females and 76.9 years for males. Scotland continues to have the lowest life expectancy of other UK countries.
However, those figures are simply the average across the country and do not show the concerning differences within the data. In 2021-23:
Life expectancy was highest in East Renfrewshire and lowest in Glasgow City for both females and males
Female life expectancy in the most deprived areas of Scotland was 10.5 years lower than in the least deprived areas
Male life expectancy in the most deprived areas of Scotland was 13.2 years lower than in the least deprived areas
The data on healthy life expectancy shows an even more pronounced inequality, with the healthy life expectancy gap of 26 years for men and 25 years for women.
The statistics above show how significant, unfair and unjust the effect of health inequalities can be. Widespread, worsening health inequalities in Scotland are causing people in our most deprived communities to effectively lose years of their potential lifespan and decades of good health, compared to those in our most affluent communities.