Danish diet and epigenetic aging in monozygotic twins: mostly familial?
In Danish monozygotic twins, higher adherence to dietary guidelines was linked to lower epigenetic age in individual-level cross-sectional analyses, but these links weakened in within-twin-pair and longitudinal analyses, suggesting genetic and shared environmental factors may explain them. [1]
Automatic summary · not editorially reviewed
The key findings
The study used monozygotic twins from the Danish GEMINAKAR cohort, established in 1997–2000 at ages 18–67, with a 12-year follow-up. [1]
In cross-sectional individual analyses, higher dietary guideline adherence was associated with lower PCGrimAge (0.55–0.67 years) and 3.1% lower DunedinPACE pace of aging per index unit. [1]
Associations were attenuated in within-twin-pair and longitudinal analyses, suggesting genetic and shared environmental factors could explain them. [1]
The source at a glance
- Study type / format
- Longitudinal twin study (abstract)
- Population / context
- Monozygotic twins in the Danish GEMINAKAR cohort, aged 18–67 years at establishment in 1997–2000.
- Summary based on
- Study abstract
- Original publication
- September 26, 2026
Diet and epigenetic clocks in Danish twins
The study asked whether following Danish dietary guidelines is associated with epigenetic age, independent of familial factors. It used monozygotic twins from the Danish GEMINAKAR cohort, established in 1997–2000 when participants were 18–67 years old, with a 12-year follow-up. Diet was recorded at both time points with food frequency questionnaires and scored with the Danish Dietary Index. Epigenetic age was estimated with established clocks (PCHannum, PCHorvath1, PCPhenoAge, PCGrimAge) and DunedinPACE. Because monozygotic twins share practically all their segregating genes and the same early-life environment, within-twin-pair analyses can account for genetic and shared environmental factors.
Supporting source [1]
Lower epigenetic age only in individual analyses
In cross-sectional individual-level analyses, higher adherence to dietary guidelines was associated with lower epigenetic age(ing). For PCGrimAge the estimate was 0.55–0.67 years lower per 1-unit increase in index score; for DunedinPACE, the pace of aging was 3.1% lower per unit. These are associations, not proof that diet causes slower epigenetic aging. In within-twin-pair and longitudinal analyses the associations were attenuated, suggesting they could be explained by genetic and shared environmental factors. The authors conclude the findings do not support strong independent associations.
Supporting source [1]
Familial factors may explain apparent diet benefits
The overall interpretation is that apparent benefits of dietary adherence on epigenetic aging may partly reflect familial factors rather than a strong independent dietary effect. The abstract reports the twin design, the dietary index, the clocks and the follow-up, but gives no twin-pair counts, effect sizes for the attenuated models, or details of the regression adjustments. It also does not report whether the dietary index changed between the two time points. These gaps limit how precisely the results can be judged.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. Twin-pair numbers, effect sizes for attenuated models, regression adjustment details and changes in the dietary index over time are not reported in the abstract. Associations are not causal.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Nygaard M, Elliott HR, Smith GD, Relton C, Kyvik KO, Dalgård C. · europepmc.org · September 26, 2026