Cross-Sectional Analysis of the Correlation Between Daily Nutrient Intake Assessed by 7-Day Food Records and Biomarkers of Dietary Intake Among Participants of the NU-AGE Study

Abstract

Methods for measuring diet composition and quantifying nutrient intake with sufficient validity are essential to study the association between nutrition and health outcomes and risk of diseases. 7-day food records provides a quantification of food actually and currently consumed and is interesting for its use in intervention studies to monitor diet in a short-term period and to guide participants toward changing their intakes. The objective of this study is to analyze the correlation/association between the daily intake of selected nutrients (collected by a 7-day food records plus a mineral/vitamin supplementation questionnaire) and estimates of energy expenditure as well as blood and urine biomarkers of dietary intakes in 1,140 healthy elderly subjects (65–79 years) at baseline of the NU-AGE intervention study (NCT01754012, clinicaltrials.gov). The results show that: the daily intake of energy correlated significantly with predicted total energy expenditure (pTEE) (ρ = 0.459, p < 0.001, and q < 0.001); protein intake correlated significantly with the ratio of 24 h urinary urea to creatinine excretion (ρ = 0.143 for total protein intake, ρ = 0.296 for animal protein intake, and ρ = 0.359 for protein intake/body weight, p < 0.001 and q < 0.001 for each correlation); vitamin B12 and folate intakes correlated significantly with their serum concentrations (ρ = 0.151 and ρ = 0.363, respectively; p < 0.001 and q < 0.001 for each correlation); sodium and potassium intakes correlated significantly with their 24 h urinary excretion (ρ = 0.298 and ρ = 0.123, respectively; p < 0.001 and q < 0.001 for each correlation); vitamin B12 and folate intakes were negatively associated with plasma homocysteine measure (p = 0.001 and p = 0.004, respectively); stratifying subjects by gender, the correlations between energy intake and pTEE and between potassium intake and its 24 h urinary excretion lost their significance in women. Even if the plasma and urinary levels of these nutrients depend on several factors, the significant correlations between daily reported intake of nutrients (protein, vitamin B12, folate, and sodium) and their blood/urinary markers confirmed that the 7-day food records (plus a supplementation questionnaire) provides reliable data to evaluate short-term current dietary intake in European elderly subjects and it can be exploited to guide and monitor NU-AGE participants through the shift of their diet according NU-AGE recommendations.

The Relationship Between Healthy Eating Motivation and Protein Intake in Community-Dwelling Older Adults With Varying Functional Status

“…Mean protein intake was 0.9 g/kg BW, which is fairly similar to the results of larger surveys reporting intakes between 0.9-1.0 g/kg BW among community-dwelling, older adults aged ≥65 years and older [12,35,36]. Nevertheless, only 37.6% reached the age-adapted, recommended amount of 1.0 g/kg BW according to the guidelines from the German Nutrition Society [37] and more than 30% had low relative protein intake <0.8 g/kg BW, the amount recommended for younger adults (Table 1).…”

Changes in Dietary Intake and Adherence to the NU-AGE Diet Following a One-Year Dietary Intervention among European Older Adults—Results of the NU-AGE Randomized Trial

“…Thirdly, to define adherence to the NU-AGE diet dietary intake data obtained by means of seven-day food records were used. Although this tool provides reliable data to evaluate short-term current dietary intake [73], in future, more objective biomarkers of dietary intake and status, such as 25-hydroxyvitamin D [74] could be incorporated in the NU-AGE index—not only to take into account the bioavailability, bioaccessibility and micronutrient status, but also to reduce misclassification bias as a result of recall bias in older adults [75]. Finally, participants were apparently healthy and well-educated [76,77], which limits the generalizability of our findings to the general elderly population.…”

Sex-Specific Associations of Blood-Based Nutrient Profiling With Body Composition in the Elderly

“…Seven-day food records as described elsewhere (Ostan et al, 2018) were used to assess dietary intake. Briefly, participants received exhaustive instructions by a trained interviewer before completing the questionnaire.…”