What to eat for healthy bones? : epidemiological studies on diet, bone health and frailty

Het belangrijkste doel van dit proefschrift was het evalueren van de relatie tussen voeding en botgezondheid en bij Nederlandse mensen van middelbare en oudere leeftijd. De voeding is nagevraagd met behulp van voedselvragenlijsten. In deze vragenlijsten hebben we nagevraagd welke voedingsmiddelen de deelnemers in onze studie consumeren en hoe vaak. Botgezondheid werd onder andere bepaald door het meten van de dichtheid van het bot, een maat voor mineralisatie. Naast botdichtheid werden in dit proefschrift ook nieuwere metingen van botgezondheid bestudeerd, die informatie geven van de structuur van het bot. Ook is er gekeken naar het risico op botbreuken op de langere termijn. De belangrijkste bevindingen van dit proefschrift zijn samengevat in de volgende paragrafen.The main aim of this thesis was to evaluate dietary intake in relation to various aspects of bone health in Dutch middle aged and elderly people. Dietary intake was assessed using Food Frequency Questionnaires (FFQs). These FFQs included a large number of food items and asked if and how often our participants habitually consumed the food items. Bone mineral density (BMD) was used as an important measure of bone health. BMD reflects the degree of mineralisation of the bones. Additionally, more novel measures of bone health that provide information on the structure of the bones were covered. Examples are the Trabecular Bone Score (TBS, a reflection of trabecular integrity) and structural measurements of hip, such as cortical bone width. Moreover, risk of fractures of different types was studied

Dietary patterns in an elderly population and their relation with bone mineral density: the Rotterdam Study

Purpose: Our aim was to identify dietary patterns that are associated with bone mineral density (BMD) against a background of relatively high dairy intake in elderly Dutch subjects. Methods: Participants were 55 years of age and older (n = 5144) who were enrolled in The Rotterdam Study, a population-based prospective cohort study. Baseline intake of 28 pre-defined food groups was determined using a validated food frequency questionnaire. Dietary patterns were identified using principal component analysis. BMD was measured using dual-energy X-ray absorptiometry at baseline and at three subsequent visits (between 1993 and 2004). Linear mixed modelling was used to longitudinally analyse associations of adherence to each pattern with repeatedly measured BMD (both in Z scores). Results: After adjustment for confounders, two dietary patterns were associated with high BMD: a “Traditional” pattern, characterized by high intake of potatoes, meat and fat (β = 0.06; 95 % CI 0.03, 0.09) and a “Health conscious” pattern, characterized by high intake of fruits, vegetables, poultry and fish (β = 0.06; 95 % CI 0.04, 0.08). The “Processed” pattern, characterized by high intake of processed meat and alcohol, was associated with low BMD (β = −0.03; 95 % CI −0.06, −0.01). Associations of adherence to the “Health conscious” and “Processed” pattern with BMD were independent of body weight and height, whereas the association between adherence to the “Traditional” pattern with BMD was not. Conclusions: Against a background of high dairy intake and independent of anthropometrics, a “Health conscious” dietary pattern may have benefits for BMD, whereas a “Processed” dietary pattern may pose a risk for low BMD

Dietary patterns and changes in frailty status: the Rotterdam study

Purpose: To determine the associations between a priori and a posteriori derived dietary patterns and a general state of health, measured as the accumulation of deficits in a frailty index. Methods: Cross-sectional and longitudinal analysis embedded in the population-based Rotterdam Study (n = 2632) aged 45 years. Diet was assessed at baseline (year 2006) using food frequency questionnaires. Dietary patterns were defined a priori using an existing index reflecting adherence to national dietary guidelines and a posteriori using principal component analysis. A frailty index was composed of 38 health deficits and measured at baseline and follow-up (4 years later). Linear regression analyses were performed using adherence to each of the dietary patterns as exposure and the frailty index as outcome (all in Z-scores). Results: Adherence to the national dietary guidelines was associated with lower frailty at baseline (β −0.05, 95% CI −0.08, −0.02). Additionally, high adherence was associated with lower frailty scores over time (β −0.08, 95% CI −0.12, −0.04). The PCA revealed three dietary patterns that we named a “Traditional” pattern, high in legumes, eggs and savory snacks; a “Carnivore” pattern, high in meat and poultry; and a “Health Conscious” pattern, high in whole grain products, vegetables and fruit. In the cross-sectional analyses adherence to these patterns was not associated with frailty. However, adherence to the “Traditional” pattern was associated with less frailty over time (β −0.09, 95% CI −0.14, −0.05). Conclusion: No associations were found for adherence to a “healthy” pattern or “Carnivore” pattern. However, Even in a population that is relatively young and healthy, adherence to dietary guidelines or adherence to the Traditional pattern could help to prevent, delay or reverse frailty levels