In the study, the analysis of the conducted at workplace interventions aimed at diabetes prevention was made. Most (4 out of 7) included in the review studies were based on the US Diabetes Prevention Program (DPP) or other, similar programs [8, 11•, 13•, 14]. A single study assessed conducting multicomponent wellness programs at workplace and its influence on the anthropometric parameters, as well as the blood glucose levels [12•]. The use of single-component interventions (i.e., dietary interventions [15], physical activity-related [9] had also been noted.

It should be noted that the type 2 diabetes risk is related to another significant health issue—the obesity [16,17,18,19]. Therefore the actions aimed at reducing body-weight may also influence diabetes risk reduction. To that effect the analysis presented in this paper had been not only of the parameters directly related to diabetes (i.e., fasting blood glucose levels or glycated hemoglobin), but of those indirectly related also (i.e., body-weight and BMI changes).

According to results of the found studies the interventions conducted at workplace can be an efficient diabetes risk reducing method. The best results were noted for interventions comprising several components, i.e., health education, diet changes or increase in physical activity [8, 11•, 12•, 13•]. The key parameters of the physical activity seem to be the intensity and longevity of the intervention (the longer and the more intensive, the better results of the analyzed parameters).

Among different types of programs, the most common are those based on DPP. Every study analyzing DPP-based programs achieved statistically significant results representing improvement of parameters such as physical activity levels, blood pressure, body-weight, BMI, HbA1c levels, and fasting blood glucose levels [8, 11•, 13•, 14]. In the 2017 Hafez study the authors had analyzed and compared non-DPP-based programs (encompassing lower than DPP intensity interventions aimed at supporting life-style changes through educational sessions, websites, and individual consultations) described in 3 studies [8]. In 2 out of 3 studies those interventions only slightly influenced body-mass reduction after 6–12 months and decrease in HbA1c levels [20, 21], while the remaining study showed an increase in blood glucose levels 2.5 years after the intervention [22].

When single component interventions were utilized separately, the effects were much smaller or inconclusive (i.e., some parameters showed improvement, while others did not change). One such example was a 2018 Shrestha study, where utilized dietary interventions in form of group or individual sessions (mean time of intervention—12 months) noted slight decrease in HbA1c levels, yet no statistical significant results were obtained for fasting blood glucose level [15].

In most of the studies found, the observation period was about 12 months. Such time is not long enough to make a clear statement about the effectiveness of the measures. It seems necessary to carry out further analyses showing the size effect after several years after the implementation of the interventions. Longevity is one of the key elements for assessing the effectiveness of interventions.

For the purpose of the discussion, current recommendations on diabetes prevention were reviewed. They referred to the types and ways of implementing interventions in people in diabetes risk groups, including overweight and obesity, low levels of physical activity, cases of diabetes in the family and the pre-diabetic state. According to recommendations, the aforementioned factors can occur both separately and simultaneously [23,24,25,26,27,28,29].

As part of preventive measures aimed at type 2 diabetes, it is recommended to implement broad educational activities focused on making the patient aware of the health risks associated with type 2 diabetes [23, 27, 29, 30]. It is also recommended to implement interventions aimed at lifestyle modification, including limiting the intake of products increasing the risk of type 2 diabetes (including fats, simple sugars, and sweetened beverages), while increasing products showing a preventive effect on the disease. Moreover, if it is deemed necessary, specific dietary patterns such as the DASH diet or the Mediterranean diet should be recommended [25, 27, 29, 31,32,33]. Increasing the level of physical activity among people at risk for type 2 diabetes should also be an important part of an intervention aimed at lifestyle modification. The main goal of encouraging the introduction of physical activity should be to reduce body weight and increase energy expenditure, especially in overweight or obese individuals [23, 25, 27,28,29, 32, 33]. Ultimately, it is recommended for people at risk for type 2 diabetes to engage in moderate-intensity physical activity tasks (e.g., volleyball, tennis, intermediate or long-distance running) at a minimum of 150 min per week [23, 25, 28, 32].

The recommendations also emphasize the need for implementation of screening aimed at type 2 diabetes. The included recommendations currently recommend the use of fasting blood glucose measurement, oral glucose tolerance test and blood glucose measurement as target screening tools. These technologies, according to the recommendations, can be used interchangeably, and the age for starting regular screening in the most recent documents is set at 35 years [23,24,25].

Some guidelines also emphasize the importance of conducting activities in the workplace [27, 29]. The National Institute for Health and Clinical Excellence recommendations emphasize that awareness-raising activities should be carried out in multiple locations. In addition to the workplace, these could include primary care facilities, pharmacies, dental offices, offices, stores, libraries, nursing homes, assisted living centers, or churches. The document also stresses that comprehensive programs should be conducted in the easily accessed workplace (at various times of the day) [27]). Conversely, another European recommendation indicates that behavioral interventions aimed at diabetes prevention may be conducted in health care facilities, the workplace, and the participant's home [29].