The Science Behind the Mental Wellbeing Score

Mental wellbeing is shaped by a complex interplay of lifestyle behaviour, biological rhythms, and psychological resilience — patterns in physical activity, sedentary behaviour, sleep regularity, and circadian alignment are each independently associated with emotional balance, psychological distress, and risk of mood disorders. The Sahha Mental Wellbeing Score synthesises these validated behavioural signals into a single evidence-based measure that reflects mental health trends.

The Scientific Model Behind the Mental Wellbeing Score

The Mental Wellbeing Score is built on six evidence-backed behavioural dimensions that research has shown influence mood, emotional stability, stress response, and psychological resilience:

• Steps: Daily step count as a measure of physical movement.
• Active hours: How many hours per day include any detected movement.
• Extended inactivity: Prolonged sedentary periods independent of exercise levels.
• Activity regularity: Day-to-day consistency of movement patterns.
• Sleep regularity: Consistency of bed and wake times across nights.
• Circadian alignment: How closely sleep timing matches the body’s biological clock.

Each dimension captures a unique aspect of daily behaviour that contributes to mental wellbeing.

Steps

Why it matters Physical activity has long been associated with lower rates of depression and anxiety. Even simple measures like step count are strongly correlated with improved mood and reduced psychological distress.

What the research shows

• Each increase of 1,000 daily steps is associated with a 6–12% lower risk of depressive symptoms.
• Individuals achieving 7,000+ steps per day have a 43–50% lower risk of depression compared to those walking less than 5,000 steps.
• Greater weekly walking time is linked with substantial reductions in depression risk.

Why it’s included in the Mental Wellbeing Score Physical movement provides neurochemical, metabolic, and psychosocial benefits that support emotional balance.

Active Hours

Why it matters Not just the amount of movement, but how consistently activity is distributed across the day, influences mood, stress regulation, and psychological wellbeing.

What the research shows

• Frequent movement throughout the day is associated with improved self-reported wellbeing and reduced psychological distress.
• Dispersed activity helps regulate mood and counteracts negative effects of prolonged inactivity.

Why it’s included in the Mental Wellbeing Score Consistent daily activity patterns correlate with better stress management and emotional stability.

Extended Inactivity

Why it matters Prolonged sedentary behaviour is linked with fatigue, low mood, and higher risk of depression and anxiety, independent of exercise levels.

What the research shows

• People in the highest categories of sedentary time (often more than 8 hours per day) have about a 25% higher risk of depressive symptoms than those with the lowest.
• Each additional hour of uninterrupted sitting is associated with increases in depression and anxiety risk.

Why it’s included in the Mental Wellbeing Score Breaking up long periods of inactivity with movement supports mental energy, mood regulation, and stress reduction.

Activity Regularity

Why it matters Regularity of routine — including consistent activity patterns — is associated with stable circadian rhythms and better psychological outcomes.

What the research shows

• Individuals with more regular activity patterns have a 23–33% lower risk of depression compared to those with highly variable routines.
• Highly variable routines are linked with higher depressive symptoms, poorer sleep, and greater perceived stress.

Why it’s included in the Mental Wellbeing Score Consistency in daily activity helps stabilise physiological and psychological rhythms that support emotional wellbeing.

Sleep Regularity

Why it matters Sleep timing consistency — going to bed and waking up at similar times — is linked to emotional regulation, lower stress, and reduced risk of mood disturbance.

What the research shows

• Each one-hour increase in sleep timing variability is associated with a 20–39% higher risk of depression and higher risk of anxiety.
• Individuals with irregular sleep schedules have up to twice the odds of experiencing depressive symptoms and lower subjective wellbeing.

Why it’s included in the Mental Wellbeing Score Consistent sleep supports emotional balance, stress resilience, and cognitive function.

Circadian Alignment

Why it matters Alignment of sleep and wake cycles with natural biological clocks influences mood, energy, and overall psychological wellbeing.

What the research shows

• Greater social jetlag (difference in sleep midpoint between workdays and free days) is associated with 23–28% higher risk of depression and lower life satisfaction.
• Individuals with more than two hours of social jetlag have approximately double the odds of depressive symptoms.

Why it’s included in the Mental Wellbeing Score Alignment with circadian rhythms reduces stress, supports cognitive function, and enhances emotional stability.

Why a Multi-Factor Mental Wellbeing Score Matters

Mental wellbeing cannot be understood through a single behaviour or metric. Two individuals with similar physical activity levels may experience different psychological outcomes depending on sleep patterns, regularity, and behavioural consistency. The Mental Wellbeing Score integrates these validated behavioural signals into a unified measure that reflects real-world lifestyle effects on emotional and psychological health.