Scientists have developed a new tool designed to measure how modern lifestyles differ from those of our ancestors and how these differences might impact health. The study, published in the journal Heliyon, introduced the Evolutionary Mismatched Lifestyle Scale (EMLS), a 36-item questionnaire that identifies behaviors and lifestyle factors that deviate from those our ancestors experienced. The results showed that individuals with higher scores on this scale were more likely to report poor physical and mental health outcomes.
The concept of evolutionary mismatch suggests that many contemporary health issues arise because our modern environment and lifestyle differ significantly from the conditions in which humans evolved. For example, the prevalence of processed foods and sedentary lifestyles contrasts sharply with the diets and activity levels of our ancestors, leading to increased rates of chronic diseases such as obesity, diabetes, and cardiovascular disease.
Despite growing interest in this theory, there has been no standardized way to measure the extent of evolutionary mismatch at an individual level. This gap motivated the researchers to develop a psychometrically sound tool that could assess how mismatched a person’s lifestyle is compared to ancestral conditions and how this mismatch relates to their health.
“There is a surge in physical and mental health-problems in modern societies and modern workplaces, which scientists attribute to our lifestyle choices and patterns. As evolutionary psychologists we are interested in how our lifestyle – in terms of what we eat, how much we move, and relate to others – is different from that of life in an ancestral world of hunter-gatherers from which we are the descendants,” said study author Mark van Vugt, a professor at the Vrije Universiteit Amsterdam in the Netherlands.
“We wanted to create a tool by which we can assess the degree of divergence – or mismatch – between these two worlds with the expectation that a greater divergence will be bad for someone’s physical and mental health. So we developed a scale, the EMLS, to gauge this difference and this study validates that scale.”
The researchers conducted a series of studies involving over 1,900 participants to develop and validate the EMLS. They started with a pilot study to generate and refine potential items for the scale, followed by three main studies to establish the scale’s structure, reliability, and validity.
The first step in developing the EMLS involved generating an initial pool of 89 items, which were based on existing research and input from experts in evolutionary behavioral science. These items covered various lifestyle domains believed to be relevant to evolutionary mismatch, such as diet, physical activity, social support, and digital media use.
Participants in the pilot study, who were recruited via an online platform, were asked to evaluate these items for clarity and relevance. The feedback collected from this pilot group led to refinements, where unclear items were revised or removed, resulting in a more polished set of items for further testing.
Following the pilot study, the first main study was conducted with a sample of nearly 800 participants. The goal was to explore whether the items could be grouped into coherent dimensions, which would form the subscales of the EMLS. The researchers employed exploratory factor analysis (EFA), a statistical technique that helps identify underlying relationships between variables, to examine the data. This analysis led to the identification of six preliminary subscales.
The second main study involved a new sample of 550 participants and aimed to confirm the factor structure identified in Study 1. This phase used confirmatory factor analysis (CFA), a more rigorous technique that tests whether the data fit the proposed model.
Based on the results, the researchers made further refinements to the scale. For example, they split the Social Media Use and Vanity scale into two distinct subscales due to conceptual differences, and they removed items related to substance use from the Romantic Relationships subscale, as they did not load strongly onto this factor. The final outcome of Study 2 was a 36-item scale divided into seven subscales: Social Media Use, Vanity, Social Support, Home Environment, Romantic and Sexual Relationships, Physical Activity, and Diet.
The final study aimed to assess the reliability and validity of the EMLS. With a new sample of 552 participants, the researchers tested whether the scale consistently measured what it was supposed to measure (reliability) and whether it accurately captured the concept of evolutionary mismatch (validity). They also examined the scale’s predictive validity by looking at its ability to predict health outcomes, such as physical health issues, mental well-being, and overall subjective health. The results showed that the EMLS was both reliable and valid, with strong associations between higher mismatch scores and poorer health outcomes.
The researchers found that higher scores on the EMLS, which indicate a greater degree of mismatch between a person’s lifestyle and their evolutionary adaptations, were associated with poorer health outcomes. Specifically, individuals with higher mismatch scores reported more physical health issues, such as sleep problems and chronic illnesses, as well as poorer mental well-being, including higher levels of depression and anxiety. Moreover, these individuals also rated their overall health as lower compared to those with lower mismatch scores.
The study also provided detailed insights into how specific lifestyle domains contribute to evolutionary mismatch and its impact on health. For example, the Social Media Use subscale was linked to higher levels of vanity and lower levels of social support, both of which were associated with poorer mental health outcomes. Similarly, the Physical Activity subscale revealed that participants who led more sedentary lifestyles, which are evolutionarily mismatched with the active lifestyles of our ancestors, reported more physical health problems.
The findings indicate “that how you feel, mentally and physically, is related to your lifestyle choices and patterns,” van Vugt told PsyPost. “The greater the difference between your lifestyle — in terms of what you eat, how much you exercise, sleep, and how you connect to others — and the way our ancestors lived for thousands of generations — as hunter-gatherers — the greater the risk of developing physical and mental health issues.”
“So you should find ways to lead a life that is more aligned to the way our ancestors lived. That does not mean that you have to go out hunting or sleep outside. But it does mean that you should be aware that the modern world contains all kinds of challenges to which your body and brain is not so well-adjusted. For example, just like our ancestors had to spend calories to obtain food, you will have to do the same. So, walk or take your bike to the supermarket and only buy the food that you really need for that day.”
These findings suggest that the EMLS can be a valuable tool for identifying individuals who may be at greater risk for health problems due to lifestyle factors that are not well-aligned with their evolutionary heritage. But the findings, like all research, come with some caveats.
One limitation is the cross-sectional nature of the study, which means that the data were collected at a single point in time. This design does not allow researchers to determine whether evolutionary mismatch causes poor health outcomes or simply correlates with them. Longitudinal studies, which follow participants over time, would help to clarify this.
“We have not followed people over time to determine if the degree of mismatch established at time 0 will result in a deterioration of one’s physical and/or mental wellbeing at time 1,” van Vugt noted.
In addition, the research was conducted exclusively with participants from the United Kingdom, raising questions about the scale’s applicability to other cultural contexts. The scale was developed based on Western perspectives and may not fully capture the evolutionary mismatches experienced by people in non-Western societies.
The researchers plan “to examine people from different cultures, classes and societies on their EMLS-scores,” van Vugt said. “For example, how does the average American adult score in comparison to say someone from the Netherlands, Denmark or Japan. And, are there differences between people from relatively low versus higher social economic classes and on what aspects of the scale? By knowing these aspects we can think about targeted interventions for specific groups of people to mitigate against evolutionary mismatches.”
The study, “Mind the Gap: Development and Validation of an Evolutionary Mismatched Lifestyle Scale and Its Impact on Health and Wellbeing,” was authored by Jiaqing O., Trefor Aspden, Andrew G. Thomas, Lei Chang, Moon-Ho Ringo Ho, Norman P. Li, and Mark van Vugt.
