An interventional study of Smoking cessation and Intermittent fasting in Healthy, Healthy Lifestyle and Smoking Cessation, sponsored by Universitaet Innsbruck. Completed at 1 site in Austria. Open to female participants aged 30 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-07.
Sponsored by Universitaet Innsbruck · Not applicable, Interventional, and Basic science
The goal of this clinical study is to learn about disease-risk and age-associated changes in DNA methylation patterns associated with disease risk or age in healthy women aged 30-60 in response to health-promoting lifestyle intervention (intermittent fasting or smoking cessation). The main questions the study aims to answer are:
The investigators also aim to explore whether DNA methylation changes are associated with changes in other biomarkers mentioned above.
Participants will be allocated to intermittent fasting or smoking cessation based on inclusion criteria. Intermittent fasting encompasses a 16:8 intermittent fasting schedule. Food intake is limited to an 8 h window per day with fasting for the remaining 16 h. Within the intermittent fasting study, participants are randomised to receive a ketogenic supplement (medium-chain triglyceride fibre) or not. Participants in the smoking cessation study will be guided to stop smoking. All participants will receive 1:1 personal coaching throughout the study, and will be provided with an optional exercise programme. All participants will also receive nutritional advice from a professional dietician throughout the study. Participants are invited to donate samples every 2 months for 6 months.
Researchers will compare signatures at the start and after 6 months of intervention. Within the intermittent fasting group, researchers will compare effects in individuals that received the ketogenic supplement to those that did not.
Background and study aims: A recent study reported that a majority of malignancies may be caused modifiable risk factors and could therefore be prevented. Smoking and diet are known risk factors for cancer but also other disorders such as cardiovascular or metabolic disorders and neurodegeneration, and may promote premature cellular ageing. The investigators and others have recently described epigenetic signatures for risk of being diagnosed, or developing future, women's cancers, as well as signatures reflecting cellular ageing and exposure to risk factors such as smoking. Utilization of DNA methylation biomarkers as surrogate endpoints indicative of current and/or future disease risk could improve future efforts in preventive medicine, both by providing information on disease risk and biofeedback. Few longitudinal studies have so far investigated the effects of lifestyle changes on DNA methylation and other biomarkers of health and disease.
TirolGESUND investigates the effect of two lifestyle interventions, smoking cessation or intermittent fasting (both with additional optional exercise), over 6 months for the promotion of health and reduction of disease risk, focusing on women's cancers.
Hypothesis: Intermittent fasting or smoking cessation for a duration of 6 months result in a modulation of scores of disease risk- and age-associated DNA methylation biomarker signatures in cervical samples, indicating a reduction of disease risk, exposure, or cellular ageing.
Study design: TirolGESUND is a baseline-controlled intervention study with two parallel arms, smoking cessation and intermittent fasting. Participants are allocated to the study arm based on eligibility criteria. Within the intermittent fasting arm, participants are randomised to receive a ketogenic supplement or not. Ketosis has been suggested to elicit beneficial metabolic alterations and could therefore further enhance beneficial effects in the dietary intervention.
Endpoints: The primary endpoint are score changes in epigenetic biomarkers of cellular ageing and disease risk, primarily recently published Women's cancer risk identification (WID) indices.
In secondary and subsidiary outcomes, the study will explore temporal and spatial dynamics of DNA methylation alterations in response to lifestyle interventions, comparing different surrogate samples (blood, buccal, cervical).
The study also investigates the impact of lifestyle intervention on other biomarkers of health and disease as a pilot study for future behavioural studies in the space of disease prevention and ageing research.
Intervention: Participants will be allocated to intermittent fasting or smoking cessation based on inclusion criteria. Intermittent fasting encompasses a 16:8 intermittent fasting schedule. Food intake is limited to an 8 h window per day with fasting for the remaining 16 h. Within the intermittent fasting study, participants are randomised to receive a ketogenic supplement (medium-chain triglyceride fibre) or not. Participants in the smoking cessation study will be guided to stop smoking. All participants will receive 1:1 personal coaching throughout the study, and will be provided with an optional exercise programme. All participants will also receive nutritional advice from a professional dietician throughout the study.
The duration of the study including intervention is 6 months for each participant. Participants are invited to return for optional sample collection visits at 12 and 18 months.
Visits and examinations: The following samples will be collected at baseline and subsequently every two months for 6 months: cervical, buccal, blood, fecal, urine and saliva samples. At the beginning and end of the study, participants will additionally receive sports medicine examinations (spirometry, ergometry/sports medicine exam) and an examination of vascular health. Participants are asked to complete an epidemiological questionnaire at the beginning of the study and receive additional questionnaires throughout the study to monitor food intake (prior to every visit), physical activity (once a month), or quality of life (baseline, 6 months). Participants may optionally donate skin biopsies at baseline and after 6 months.
Participants receive a fitness tracker to monitor physical activity and exercise in an objective manner. Some participants in the intermittent fasting group are receiving a capillary blood monitor to evaluate ketosis levels at the end of the fasting period three times a week.
Randomization in the intermittent fasting study arm: Participants are randomised to receive or to not receive ketogenic supplement 1:1 using menopause- and BMI-stratified block randomization.
Participant risks and benefits: Participants will receive support in implementing (putative) health-promoting interventions, including giving up smoking and intermittent fasting over 6 months, and are hence expected to personally benefit from participation. Risks are expected to be minimal as the study involves only a behavioural/lifestyle change, but can include e.g. development of haematoma after blood sampling, mood swings due to smoking cessation, or hunger at the initiation of intermittent fasting.
Sample size: Dynamics of DNA methylation changes are unknown at the start of the study, rendering sample size estimation challenging. For each study arm (intermittent fasting, intermittent fasting plus ketogenic supplement, smoking cessation) n=60 participants are recruited based on prior information of standard deviation in DNA methylation indices.
Expected Drop-Out levels: Based on prior literature in lifestyle or dietary interventions, drop-out rates of 15-20% are expected.
Data management and protection: Clinical data is recorded using an electronic case report form with validity checks. Laboratory data is analysed in a coded manner. Data protection follows the principles of the European General Data Protection Regulation (GDPR).
Quality control: Standard operating procedures for sample collection and clinical procedures have been designed and implemented.
304 studies on the registry are indexed under Smoking Cessation; 139 are open to participants now.
This study's enrollment of 156 is close to the median of 154 across 285 interventional studies indexed under Smoking Cessation.
Browse Smoking Cessation studies →Universitaet Innsbruck is the lead sponsor of 12 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Smoking cessation intervention:
3a. Smoking cessation: ≥10 cigarettes per day for at least the last five years
Dietary intervention:
3b Dietary intervention: BMI between 25 and 35
NB [Nota Bene], should 3a and 3b apply, participant will be allocated to the smoking cessation intervention.
Exclusion Criteria:
Relevant underlying conditions:
Smoking cessation encompasses three guided smoking cessation group therapy sessions (6-12 participants per session) followed by smoking cessation (occuring in the second session) for 6 months. Participants receive an optional exercise programme and motivational coaching over the duration of the study.
Behavioral: Smoking cessation
The dietary intervention encompasses induction (1 month) and maintenance (5 months) of a 16:8 intermittent fasting regime (time restricted eating to 8 h a day, fasting for remaining 16 h). During the introductory month, participants will only maintain a 14:10 intermittent fasting regime. Participants are randomized to receive a ketogenic supplement, medium-chain triglyceride fiber, to use daily. Participants receive an optional exercise programme and motivational coaching over the duration of the study.
Behavioral: Intermittent fasting · Behavioral: Intermittent fasting with ketogenic supplement
Smoking cessation encompasses three guided smoking cessation group therapy sessions (6-12 participants per session) followed by smoking cessation (occuring in the second session) for 6 months. Participants receive an optional exercise programme and motivational coaching over the duration of the study.
The dietary intervention encompasses induction (1 month) and maintenance (5 months) of a 16:8 intermittent fasting regime (time restricted eating to 8 h a day, fasting for remaining 16 h). During the introductory month, participants will only maintain a 14:10 intermittent fasting regime. Participants receive an optional exercise programme and motivational coaching over the duration of the study.
The dietary intervention encompasses induction (1 month) and maintenance (5 months) of a 16:8 intermittent fasting regime (time restricted eating to 8 h a day, fasting for remaining 16 h). During the introductory month, participants will only maintain a 14:10 intermittent fasting regime. Participants receive a ketogenic supplement, medium-chain triglyceride fiber, to use daily. Participants receive an optional exercise programme and motivational coaching over the duration of the study.
Change from baseline scores of DNA methylation biomarkers of age, disease risk, and exposure
Examination of change in epigenetic age, disease risk, and exposure signature scores compared to baseline (before and after intervention, i.e. baseline-controlled) in cervical samples. DNA methylation levels will be measured using the Illumina MethylationEPIC array and computed using previously described methylation indices, including: * WID-BC (Women's risk identification - Breast cancer) * WID-OC (ovarian cancer) * WID-EC (endometrial cancer) * WID-CIN (cervical intraepithelial neoplasia) * WID-REA (relative epithelial age) * WID-RIA (relative immune age) * pcgtAge (mitotic clock) * WID-SOLA\[ge\] (systemic organ life age) * WID-SMK (smoking)
Time frame: Baseline, Month 6 (per participant)
Description of study characteristics: registration rate in percent (%)
Final registration rate of participants initially interested, i.e. those who signed up for information webinars, in percent (%)
Time frame: Baseline
Description of study characteristics: drop-out rate in percent (%)
Number of included participants who dropped out over the course of the study, in percent (%)
Time frame: Month 6 (Primary end point of study)
Description of study characteristics: compliance rate in percent (%)
Description of compliance rate (i.e. days compliant with the intervention over the duration of the study), in percent (%)
Time frame: Month 6 (Primary end point of study)
Change in DNA methylation scores from baseline in cervical samples at month 2, month 4, and month 6
Examination of change in epigenetic age, disease risk, and exposure signature scores compared to baseline (before and after intervention, i.e. baseline-controlled) in cervical samples collected at baseline and again at month 2, 4, and 6, using t Tests and/or linear mixed-effects models where appropriate. DNA methylation levels will be measured using the Illumina MethylationEPIC array and computed using previously described methylation indices, including: * WID-BC * WID-OC * WID-EC * WID-CIN * WID-REA (relative epithelial age) * WID-RIA (relative immune age) * pcgtAge (mitotic clock) * WID-SOLA\[ge\] * WID-SMK The change in scores will also be compared to changes in the same scores in buccal and blood samples (outcomes 6 and 7) to evaluate temporal and spatial DNA methylation dynamics in response to lifestyle intervention.
Time frame: Samples collected at baseline, month 2, month 4, and month 6
Change in DNA methylation scores from baseline in buccal samples at month 2, month 4, and month 6
Examination of change in epigenetic age, disease risk, and exposure signature scores compared to baseline (before and after intervention, i.e. baseline-controlled) in buccal samples collected at baseline and again at month 2, 4, and 6, using t Tests and/or linear mixed-effects models where appropriate. DNA methylation levels will be measured using the Illumina MethylationEPIC array and computed using previously described methylation indices, including: * WID-BC * WID-OC * WID-EC * WID-CIN * WID-REA (relative epithelial age) * WID-RIA (relative immune age) * pcgtAge (mitotic clock) * WID-SOLA\[ge\] * WID-SMK The change in scores will also be compared to changes in the same scores in cervical and blood samples (outcomes 5 and 7) to evaluate temporal and spatial DNA methylation dynamics in response to lifestyle intervention.
Time frame: Samples collected at baseline, month 2, month 4, and month 6
Change in DNA methylation scores from baseline in blood samples at month 2, month 4, and month 6
Examination of change in epigenetic age, disease risk, and exposure signature scores compared to baseline (before and after intervention, i.e. baseline-controlled) in blood samples collected at baseline and again at month 2, 4, and 6, using t Tests and/or linear mixed-effects models where appropriate. DNA methylation levels will be measured using the Illumina MethylationEPIC array and computed using previously described methylation indices, including: * WID-BC * WID-OC * WID-EC * WID-CIN * WID-REA (relative epithelial age) * WID-RIA (relative immune age) * pcgtAge (mitotic clock) * WID-SOLA\[ge\] * WID-SMK The change in scores will also be compared to changes in the same scores in cervical and buccal samples (outcomes 5 and 6) to evaluate temporal and spatial DNA methylation dynamics in response to lifestyle intervention.
Time frame: Samples collected at baseline, month 2, month 4, and month 6
Change in beneficial and harmful microbial species compared to baseline, in percent (%)
Quantification of selected beneficial and harmful bacteria based on previous literature, in fecal and saliva samples, and computation of change from baseline. If big differences are found, temporal dynamics of changes will be examined in samples collected at month 2 and month 4.
Time frame: Samples collected at baseline and month 6, optional month 2 and month 4
Change in microbial diversity score compared to baseline, in percent (%)
Quantification of microbial diversity using entropy scores at baseline and month 6. If big differences are found, temporal dynamics of changes will be examined in samples collected at month 2 and month 4.
Time frame: Samples collected at baseline and month 6, optional month 2 and month 4
Change of immune and inflammatory cell populations in peripheral blood
Immune/inflammatory cell heterogeneity will be investigated in samples from peripheral blood using flow cytometry using well-established cellular markers. Cell population changes from baseline will be reported. If big differences are found, temporal dynamics of changes will be examined in samples collected at month 2 and month 4. Pending the outcome of this investigation, targeted investigation of associated plasma circulating markers may be conducted.
Time frame: Samples collected at baseline and month 6, optional month 2 and month 4
Change in body mass index from baseline
Changes in BMI from baseline (diet arm of the study). Changes in BMI from baseline (diet arm of the study).
Time frame: Baseline and month 6.
Change in body composition as quantified by bioelectric impedance analysis from baseline
Change in body composition (% muscle, fat, water, abdominal fat composition) composition from baseline as quantified by bioelectric impedance analysis (diet arm of the study).
Time frame: Baseline and month 6.
Change in smoking status from baseline
Changes in smoking status (smoking cessation arm of the study), defined as: smoking - yes/no.
Time frame: Baseline and month 6.
Change in vascular health from baseline: pulse-wave velocity
Change in measured pulse wave velocity (m/s) as recorded using the vicorder.
Time frame: Baseline and month 6.
Change in vascular health from baseline: intima-media thickness
Change in measured vascular intima-media thickness as measured using ultrasound.
Time frame: Baseline and month 6.
Change in vascular health from baseline: intima-media thickness
Change in measured vascular plaque score as measured using ultrasound.
Time frame: Baseline and month 6.
Change in physical activity from baseline
Change in physical activity from baseline, as quantified using the international physical activity questionnaire (IPAQ)
Time frame: Baseline and month 6
Change in physical activity from baseline: fitness tracker data
Change in physical activity from baseline as quantified using fitness tracker data (resting heart rate month 0 to resting heart rate month 6)
Time frame: Baseline and month 6
Change in physical activity from baseline: VO2max
Change in physical activity from baseline as quantified via sports examination (VO2max)
Time frame: Baseline and month 6
Change in pulmonary health from baseline
Pulmonary health markers, e.g. FEV1 (Forced expiratory volume), at baseline and at 6 months using spirometry
Time frame: Baseline and month 6
Change in health-related quality of life from baseline
Change in health-related quality of life (EuroQoL, i.e. EQ-5D-5L, https://euroqol.org/eq-5d-instruments/eq-5d-5l-about/) at baseline and at 6 months
Time frame: Baseline and month 6
Exploratory investigation of metabolic profile via NMR over course of intervention for hypothesis generation
The investigators will examine metabolome profiles in urine and saliva samples using untargeted nuclear magnetic resonance (NMR) for hypothesis generation of future intervention trials.
Time frame: Urine and saliva samples collected at baseline, month 2, month 4, and month 6
Change of plasma inflammatory markers compared to baseline.
Pending the outcome of this investigation, targeted investigation of associated plasma circulating markers may be conducted. Appropriate inflammatory markers will be investigated using a sufficiently sensitive method, such as high sensitivity ELISA or luminex bead arrays.
Time frame: Samples collected at baseline and month 6, optional month 2 and month 4
Plan to share: Yes — The datasets generated during and/or analysed during the current study, in particular epigenetic, metabolomic, and microbial will be stored in a publicly available but access-controlled repository (EGA-European Genome Phenome Archive, https://ega-archive.org/, or similar), due to the sensitive nature of epigenetic data. All data will only be shared in a coded (pseudonymised) or completely anonymised format. Prior to use, any potential collaborators must sign a data access agreement and comply with the terms of data sharing. Some datasets (summary characteristics, or completely anonymised results) may additionally be published as a supplement to the results publications.
Supporting information: Sap, Csr, Analytic code
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