The Health Insurance Group has found that of 50,000 health MOTs in the workplace last year 17% of the UK workforce had a BMI greater than 30 - defined as ‘clinically obese' by the World Health Organisation.
The healthcare intermediary's study of UK also revealed that 68% of men had a "high or very high body fat content" and 54% of women were also "high or very high."
Some 33% men had high blood pressure (hypertension i.e. above 140/90) while 19% women recorded higher than normal levels.
If left untreated, high blood pressure increases the risk of a heart attack or stroke and is often referred to as a "silent killer", the intemediary warned.
The results were part of a study with the Wellbeing People based on delivery of interactive health kiosks to UK businesses to get individuals thinking more about health and wellbeing.
Brett Hill, director of The Health Insurance Group said: "The results aren't that surprising since the NHS has shifted its focus from sickness and cure to wellness and prevention, to better manage long term medical conditions and other issues relating to old age.
"The kiosks provided some intriguing data about workplace health and have shown they are the perfect tool for building awareness around the importance of health issues and engaging people in a way that's convenient and non-invasive; fitting in around their working day."