Most HR and benefits leaders know their sickness absence numbers. They track days off, monitor absence rates, and report to the board on headcount availability. What the vast majority are not tracking is the more expensive problem sitting directly underneath those numbers.
Presenteeism, meaning employees showing up to work while managing uncontrolled or unaddressed chronic conditions, costs UK employers an estimated £103 billion per year, according to the Institute for Public Policy Research. The average UK employee loses 44 full days of productivity annually while technically present at their desk. For every £1,000 an organisation loses to absenteeism, it loses £3,500 to presenteeism. Legal & General's research puts the ratio even higher: presenteeism costs employers three times what sickness absence does.
HR teams are measuring the smaller number.
The hidden iceberg of chronic disease at work
Absence data captures the tip. Chronic conditions, including Type 2 diabetes, obesity, cardiovascular disease, and hypertension, do not primarily affect employees by keeping them home. They affect employees through fatigue, cognitive impairment, reduced concentration, and the sustained low-grade drag of managing a long-term condition while trying to perform at work.
The data makes this concrete:
- 78% of obesity-related workplace costs come from presenteeism, not absenteeism. The medical bills and sick days are visible in claims data. The productivity loss is not (Nature, Nutrition & Diabetes, 2024).
- Employees with a chronic health condition are significantly more likely to report presenteeism than absenteeism. The condition is more predictive of showing up impaired than of not showing up at all (CDC, 2016).
- In a workforce of 10,000 employees, average annual costs from obesity alone run to £22 million, with the majority of that figure invisible to standard HR reporting.
- Employees working with unmanaged chronic conditions lose up to 80 work hours per year to reduced performance. Cardiometabolic conditions produce some of the highest incremental productivity losses of any health category (Journal of Medical Economics, 2023).
The absence dashboard tells HR what happened. It does not tell HR what is happening right now across the workforce, or what will happen in three years when today's pre-diabetic population becomes tomorrow's diagnosed one.
What HR is actually measuring, and what it misses
The standard HR data stack for workforce health typically includes:
- Absence rates: days off, return-to-work timelines, patterns by department
- Claims data: what employees used the health benefit for, which conditions are driving cost
- EAP utilisation: how many employees accessed mental health or counselling support
- Benefits engagement: how many employees enrolled in a programme, not whether it worked
What is absent from most HR reporting:
- Presenteeism impact: any measure of impaired performance while present
- Upstream risk: the proportion of the workforce with pre-diabetes, early metabolic risk, or obesity before it triggers a diagnosis or a claim
- Programme outcomes: not just whether employees enrolled in a wellness benefit, but whether their clinical markers improved
- Productivity-health linkage: any attempt to connect health data with performance, tenure, or absence trends over time
It is a failure of infrastructure. Most corporate health programmes were not designed to generate this data. They were designed to provide access (a GP line, an app, a gym discount) without a feedback loop that tells HR whether any of it is working.
The upstream problem nobody is screening for
Here is the number that tends to stop HR leaders in their tracks: up to 1 in 3 employees may have prediabetes, and the majority of them do not know it.
Prediabetes carries no acute symptoms. An employee in this state is not off sick. They are at their desk, in meetings, responding to emails, operating at a cognitive and physical capacity below what they are capable of. Over time, without intervention, prediabetes progresses to Type 2 diabetes in a significant proportion of cases. That progression takes years. During those years, productivity loss accumulates quietly, and the employer is paying for it without knowing it exists.
By the time a condition shows up in claims data, the organisation has already absorbed years of subclinical productivity loss and missed the window where early intervention is most effective and least expensive.
The WHO's Global Action Plan for the Prevention and Control of Noncommunicable Diseases is explicit on this: early identification and lifestyle-based intervention in metabolic conditions produces substantially better clinical and economic outcomes than treatment after diagnosis. The window exists. Most employers are not using it.
What better measurement looks like
HR teams that are building serious health-productivity programmes are moving beyond access metrics toward outcome metrics. The shift involves three things:
1. Measuring what changes, not just what is used. Enrolment in a programme is a leading indicator. HbA1c improvement, sustained weight reduction, and blood pressure normalisation are the metrics that tell you whether the programme is doing anything. Benefits leaders who require outcome data from their providers are operating with a fundamentally better feedback loop than those who track utilisation alone.
2. Connecting health data to workforce data. Where data sharing agreements allow, linking health programme outcomes to absence rates, performance reviews, and retention data surfaces the productivity-health relationship that most organisations suspect but cannot demonstrate. This is the evidence base that justifies continued investment.
3. Addressing the risk population, not just the diagnosed population. Screening for pre-diabetic risk, obesity, and cardiovascular markers at the population level, even through voluntary self-reporting, gives HR a picture of where the workforce is heading, not just where it is now. Prevention programmes at this stage cost a fraction of chronic disease management at the clinical stage.
How Liva approaches this for corporate and occupational health clients
Liva's platform is designed to generate the outcome data that standard corporate health programmes do not produce. Certified health coaches work with employees through a structured behaviour change programme, with clinical markers tracked throughout: weight, HbA1c, activity levels, and self-reported wellbeing. The clinician portal gives programme leads real-time visibility into cohort-level outcomes, not just individual engagement. For corporate and occupational health clients, Liva provides reporting that connects programme participation with measurable health improvement, giving HR teams the evidence base they need to make the business case for continued investment. Liva is one of seven digital weight-management technologies recommended by NICE for use in the NHS, with a randomised controlled trial demonstrating 4.5 kg mean weight loss versus 1.5 kg in usual care (Hesseldal et al., JMIR, 2022).
Chronic disease is already costing your workforce. HR leaders have answered the question of whether to act. The harder question is whether to keep measuring only what is visible, or to build the infrastructure to see what is not.
