Role of Planetary Health Diet in the association between genetic susceptibility to obesity and anthropometric measures in adults.

BACKGROUND/OBJECTIVE: The roles of overall diet quality in linking genetic background with anthropometric measures are unclear, particularly regarding the recently developed Planetary Health Diet (PHD). This study aims to determine if the PHD mediates or moderates the relationship between genetic susceptibility to obesity and anthropometric measures. SUBJECTS/METHODS: The study involved 2942 individuals from a Finnish population-based cohort (54% women, mean age 53 (SD ± 13) years). Habitual diet was assessed using a validated 130-item food frequency questionnaire, and the PHD Score (total score range 0-13 points) was adapted for Finnish food culture to evaluate diet quality. Genetic susceptibility to obesity was evaluated with a polygenic risk score (PRS) based on one million single nucleotide polymorphisms associated with body mass index (BMI). Baseline anthropometrics included weight, height, waist circumference (WC), and body fat percentage, with changes in these measures tracked over 7 years. A five-step multiple linear regression model and multivariable logistic regression with interaction terms were used to assess the mediating and moderating effects of the PHD. These analyses were also replicated in another Finnish cohort study (2 834 participants). RESULTS: PRS for BMI was positively associated with baseline BMI and changes in anthropometric measures, except waist circumference (p = 0.12). Significant associations were observed for baseline BMI and WC (p < 0.001), changes in BMI and WC (p = 0.01), and body fat percentage change (p = 0.05). However, the PHD (average score 3.8 points) did not mediate or moderate these relationships. These findings were consistent in the replication cohort. CONCLUSION: Diet quality assessed with the PHD did not mediate or moderate the associations between genetic susceptibility to obesity and anthropometric measures. This lack of effect may be partly due to low adherence to the PHD and the older age of participants ( > 50 years) at baseline.

Partial substitution of red or processed meat with plant-based foods and the risk of type 2 diabetes.

High consumption of red and processed meat has been associated with increased type 2 diabetes (T2D) risk. These kinds of diets are also environmentally unsustainable. We examined a modeled association between a partial substitution of red meat or processed meat with plant-based foods (legumes, vegetables, fruit, cereals, or a combination of these) and T2D risk among Finnish adults. We used pooled data from five Finnish cohorts (n = 41,662, 22% women, aged ≥ 25 years, 10.9 years median follow-up with 1750 incident T2D cases). Diet was assessed by a validated food frequency questionnaire. In the substitution models, 100 g/week of red meat or 50 g/week of processed meat were substituted with similar amounts of plant-based substitutes. Cohort-specific hazard ratios (HRs) were estimated by Cox proportional hazards multivariable model and pooled using a two-staged random-effects model. We observed small, but statistically significant, reductions in T2D risk in men when red or processed meat were partially substituted with fruits (red meat: HR 0.98, 95% CI 0.97-1.00, P = 0.049, processed meat: 0.99, 0.98-1.00, P = 0.005), cereals (red meat: 0.97, 0.95-0.99, P = 0.005, processed meat: 0.99, 0.98-1.00, P = 0.004) or combination of plant-based foods (only processed meat: 0.99, 0.98-1.00, P = 0.004) but not with legumes or vegetables. The findings of women were similar but not statistically significant. Our findings suggest that even small, easily implemented, shifts towards more sustainable diets may reduce T2D risk particularly in men.

Associations of EAT-Lancet Planetary Health Diet or Finnish Nutrition Recommendations with changes in obesity measures: a follow-up study in adults.

Background: Knowledge on the association between the EAT-Lancet Planetary Health Diet (PHD) or the Finnish Nutrition recommendations (FNR) and anthropometric changes is scarce. Especially, the role of the overall diet quality, distinct from energy intake, on weight changes needs further examination. Objectives: To examine the association between diet quality and weight change indicators and to develop a dietary index based on the PHD adapted for the Finnish food culture. Methods: The study population consisted of participants of two Finnish population-based studies (n = 4,371, 56% of women, aged 30-74 years at baseline). Dietary habits at the baseline were assessed with a validated food frequency questionnaire including 128-130 food items. We developed a Planetary Health Diet Score (PHDS) (including 13 components) and updated the pre-existing Recommended Finnish Diet Score (uRFDS) (including nine components) with energy density values to measure overall diet quality. Weight, height, and waist circumference (WC), and the body mass index (BMI) were measured at the baseline and follow-up, and their percentual changes during a 7-year follow-up were calculated. Two-staged random effects linear regression was used to evaluate ß-estimates with 95% confidence intervals. Results: Adherence to both indices was relatively low (PHDS: mean 3.6 points (standard deviation [SD] 1.2) in the range of 0-13; uRFDS: mean 12.7 points (SD 3.9) in the range of 0-27). We did not find statistically significant associations between either of the dietary indices and anthropometric changes during the follow-up (PHDS, weight: ß -0.04 (95% CI -0.19, 0.11), BMI: ß 0.05 (-0.20, 0.10), WC: ß -0.08 (-0.22, 0.06); uRFDS, weight: ß 0.01 (-0.04, 0.06), BMI: ß 0.01 (-0.04, 0.06), WC: ß -0.02 (-0.07, 0.03)). Conclusion: No associations between overall diet quality and anthropometric changes were found, which may be at least partly explained by low adherence to the PHD and the FNR in the Finnish adult population.

Association between social jet lag, quality of diet and obesity by diurnal preference in Finnish adult population.

The evening type has been associated with unhealthy behaviors and adverse health outcomes, such as unhealthy dietary habits and obesity. Misalignment between biological and social rhythms, referred to as social jet lag (SJL), has been considered to explain these outcomes, because evening types are more prone to SJL. However, the existing evidence has been inconsistent and SJL by diurnal preference has hardly been examined. We examined the associations between SJL, the quality of the diet, and the prevalence of obesity by diurnal preference. This dataset included 6779 Finns (55% women, aged 25-74 years) from the National FINRISK 2012 and DILGOM 2014 studies. Diurnal preference was assessed with a shortened version of the Morningness-Eveningness Questionnaire (MEQ). SJL was calculated with the sleep-corrected formula (SJLsc). SJL was divided into three groups by the degree of SJL (<1h, ≥1h but <2h and ≥2h). The dietary intake was assessed with a validated food frequency questionnaire (FFQ) and the quality of the diet with the Baltic Sea Diet Score. Body weight, height, and waist circumference (WC) were measured, and the body mass index (BMI) was calculated (kg/m2). Analysis of covariance (ANCOVA) followed by Bonferroni multiple comparison post-hoc tests and logistic regression models were used to analyze the differences between the lowest and the highest SJL groups by diurnal preference. In the highest SJL group (≥2h), there were more evening types than morning types (7%-points, p < .001). Overall, those in the highest SJLsc group were on average younger than those in the lowest SJLsc group (p< .001). Also, those in the highest SJLsc group tended to have lower adherence to the Baltic Sea Diet compared to the participants in the lowest SJLsc group, but this difference reached significance only in morning types (p = .006). Furthermore, morning types in the highest SJLsc group had higher BMI and WC compared to the morning types in the lowest SJLsc group (BMI, p = .016; WC, p = .012). In conclusion, evening types had on average more SJL than morning types, but the degree of SJL was associated with the quality of the diet and obesity only in the morning types.