Onnikka weight management intervention developed at the University of Oulu reduces the need for antihypertensive medication in the long term
The five-year study, which began in 2012, included 532 working-age individuals with a body mass index (BMI) of 27–35 kg/m². Participants used Onnikka for one year, with some also receiving varying lengths of group counselling led by a clinical nutritionist or nurse. One-third of the participants used Onnikka without any face-to-face guidance. Their health status and weight were monitored at follow-up visits one, two, and five years after the intervention. The results were compared with a control group that did not use Onnikka.
Long-term health benefits of weight management
At the two-year follow-up, it was observed that those who had used Onnikka for one year experienced significant weight loss. The best results were achieved when Onnikka use was combined with group counselling based on cognitive behavioural therapy (CBT). Using this method, individuals living with obesity (BMI 30–35 kg/m²) lost an average of nearly five kilograms, and this result was maintained for at least two years. Using Onnikka alone led to an average weight loss of approximately two kilograms.
The newly published five-year follow-up results showed that the weight of those who had used Onnikka for one year had returned to baseline, whereas the control group's weight had continued to increase. Although the initial weight loss was not maintained over five years, the area-under-the-curve (AUC) analysis over the entire five-year period demonstrated that the Onnikka group benefited significantly from the one-year intervention in terms of weight management. Furthermore, the positive effects of the Onnikka programme on cardiovascular health were still evident.
"The reduction in the need for antihypertensive medication suggests that the benefits of the programme may persist long after the lifestyle changes have been made," says Professor Markku Savolainen, who led the study.
The study indicates that Onnikka provides an effective way to support weight management and promote heart health, with benefits potentially lasting several years. Previous research has also shown that the prevalence of metabolic syndrome decreased significantly among Onnikka users.
Onnikka is an independently functioning digital lifestyle coaching method that has been developed and studied at the University of Oulu for over 15 years. The app combines cognitive behavioural therapy with persuasive design techniques, and its effectiveness in weight loss has been confirmed in multiple scientific studies.
Research Publication: Turkkila, E., Pekkala, T., Merikallio, H. et al. Five-year follow-up of a randomized weight loss trial on a digital health behaviour change support system. Int J Obes (2025).
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