Biochemical validation of the older Australian's food frequency questionnaire using carotenoids and vitamin E

The assessment of dietary carotenoid intake of the Cardio-Med FFQ using food records and biomarkers in an Australian cardiology cohort: a pilot validation

Dietary carotenoids are associated with lower risk of CHD. Assessment of dietary carotenoid intake using questionnaires can be susceptible to measurement error. Consequently, there is a need to validate data collected from FFQs which measure carotenoid intake. This study aimed to assess the performance of the Cardio-Med Survey Tool (CMST)-FFQ-version 2 (v2) as a measure of dietary carotenoid intake over 12-months against plasma carotenoids biomarkers and 7-Day Food Records (7DFR) in an Australian cardiology cohort. Dietary carotenoid intakes (β- and α-carotene, lycopene, β-cryptoxanthin and lutein/zeaxanthin) were assessed using the 105-item CMST-FFQ-v2 and compared to intakes measured by 7DFR and plasma carotenoid concentrations. Correlation coefficients were calculated between each dietary method, and validity coefficients (VCs) were calculated between each dietary method and theoretical true intake using the 'methods of triads'. Thirty-nine participants aged 37-77 years with CHD participated in the cross-sectional study. The correlation between FFQ and plasma carotenoids were largest and significant for β-carotene (0.39, p=0.01), total carotenoids (0.37, p=0.02) and β-cryptoxanthin (0.33, p=0.04), with weakest correlations observed for α-carotene (0.21, p=0.21) and lycopene (0.21, p=0.21). The FFQ VCs were moderate (0.3-0.6) or larger for all measured carotenoids. The strongest were observed for total carotenoids (0.61) and β-carotene (0.59), while the weakest were observed for α-carotene (0.33) and lycopene (0.37). In conclusion, the CMST-FFQ-v2 measured dietary carotenoids intakes with moderate confidence for most carotenoids, however, there was less confidence in ability to measure α-carotene and lycopene intake, thus further research is warranted using a larger sample.

Development and Functionality of a Parsimonious Digital Food Frequency Questionnaire for a Clinical Intervention among an Indigenous Population

Nutrition-related chronic diseases are a major problem among Indigenous populations. Appropriate dietary intake assessment tools are needed for nutritional surveillance and intervention; however, tools designed to measure the habitual dietary intake of Indigenous persons are largely lacking. We developed a digital food frequency questionnaire (FFQ) to measure habitual consumption among Australian Aboriginal adults and support personalized nutrition counseling. The primary contributors to energy, select nutrients, and inter-person variation (83 food groups) were identified from nationally representative 24 h recall (24HR) data, and they accounted for >80% of the total intake and inter-person variation of the nutrients of interest. Based on community input, a meal-based FFQ format was adopted, with a main food/beverage list of 81 items and the capacity to report on >300 additional items via the digital platform. The nutrient database was based on the Australian Food and Nutrient Database. Data for the first 60 study participants (70% female; median age: 48 years) were used to assess the FFQ's utility. The participants' median [IQR] reported energy intake (10,042 [6968-12,175] kJ/day) was similar to their median [IQR] estimated energy expenditure (10,197 [8636-11,551] kJ/day). Foods/beverages on the main FFQ list accounted for between 66% and 90% of the participants' reported energy and nutrient intakes; the remainder came from participant-selected extra items. The digital FFQ platform provides a potentially valuable resource for monitoring habitual dietary intake among Aboriginal adults and supporting chronic disease prevention and management interventions.

Dietary Vitamin E Isoforms Intake: Development of a New Tool to Assess Tocopherols and Tocotrienols Intake in Adults

Due to the documented health benefits of tocopherols and tocotrienols as bioactive compounds, it seems important to assess their intake. The aim of this study was to develop a new tool and its application for assessment of tocopherol and tocotrienol intake in adults. Dietary data were collected by semiquantitative FFQ (VitE-FFQ) and by a 1-day dietary record in a group of 447 subjects. The database of the US Department of Agriculture (USDA) was used to calculate the individual isoforms of vitamin E and develop the tool-VIT_E.CAL. The assessment of measuring agreement between the two methods was conducted by analysis of the correlations and Bland-Altman plots. The average α-tocopherol intake was 11.3 mg/day for the data obtained using the FFQ method and 12.8 mg/day for the results obtained using the 1-day dietary record. Depending on the adopted recommendation, only 40-57% of the subjects had adequate vitamin E intake. The intake of α-tocopherol did not exceed the UL value in any of the respondents. The dominant forms of vitamin E in the diet of the studied group were α- and γ- forms (55% and 38% of the total sum) among tocopherols and β- and γ- forms (49% and 24% of the total sum) among tocotrienols. VIT_E.CAL allows us to calculate not only the total amount of vitamin E but also its eight isoforms. It can be a useful tool to assess individual and group intake of various forms of vitamin E in the diet. The use of VIT_E.CAL enables the proper assessment of vitamin E (as α-tocopherol and not α-tocopherol equivalent) in the diet of Poles, and most likely also in the European diet. The obtained results indicate the need to take into account the content of individual forms of vitamin E in food/diet, which will allow for a reliable assessment of its consumption. It also seems necessary to standardize the nomenclature regarding the name of vitamin E and its use for correct nutritional assessment.

Dietary vitamin E and tocopherol isoforms and incident chronic kidney disease: A 30-y follow-up study from young adulthood to midlife

BACKGROUND

The relationship of dietary vitamin E intake with incident chronic kidney disease (CKD) was not clear as yet. We aimed to examine the associations of dietary total vitamin E and tocopherol isoforms intakes with incident CKD in a 30-year follow-up study from young adulthood to midlife.

METHODS

A total of 4038 American adults aged 18-30 years and without reduced estimated glomerular filtration rate (eGFR) were enrolled from Coronary Artery Risk Development in Young Adults study. Diet was evaluated by a validated dietary-history questionnaire at baseline, and after 7 and 20 years later. The study outcome was incident CKD, defined as an eGFR<60 mL/min/1.73 m² or a urinary albumin to creatinine ratio ≥30 mg/g.

RESULTS

During a 30-year follow-up, 642 (15.9%) participants developed incident CKD. Overall, there was a L-shaped relationship between dietary total vitamin E intake and incident CKD (P for non-linearity<0.001). When total vitamin E intake was assessed as quartiles, compared with those in the first quartile (<4.35 mg α-TE/1000 kcal), the adjusted HRs (95%CI) of incident CKD for participants in the fourth quartile (≥9.61 mg α-TE/1000 kcal) was 0.55 (0.40, 0.75). Moreover, higher intakes of beta-tocopherol and gamma-tocopherol were significantly associated with a lower incident CKD. Higher intake of delta-tocopherol was significantly related to a higher incident CKD. And there was no obvious association of alpha-tocopherol intake with incident CKD.

CONCLUSIONS

There were inverse associations of total vitamin E, beta-tocopherol and gamma-tocopherol intakes, a positive association of delta-tocopherol intake, and no obvious association of alpha-tocopherol intake, with incident CKD among American adults.

Dietary β-Cryptoxanthin and α-Carotene Have Greater Apparent Bioavailability Than β-Carotene in Subjects from Countries with Different Dietary Patterns

β-carotene, α-carotene and β-cryptoxanthin are greater contributors to vitamin A intake than retinol in the human diet for most people around the world. Their contribution depends on several factors, including bioavailability and capacity of conversion into retinol. There is an increasing body of research showing that the use of retinol activity equivalents or retinol equivalents could lead to the underestimation of the contribution of β-cryptoxanthin and of α-carotene. The aim is to assess their apparent bioavailability by comparing concentrations in blood to their dietary intakes and identifying the major food contributors to their dietary intake. Dietary intake (3-day 24-h records) and serum concentrations (by HPLC) were calculated in normolipemic subjects with adequate retinol status (≥1.1 µmol/L) from our studies (n = 633) and apparent bioavailability calculated from 22 other studies (n = 29,700). Apparent bioavailability was calculated as the ratio of concentration in the blood to carotenoid intake. Apparent bioavailabilities for α-carotene and β-cryptoxanthin were compared to those for β-carotene. Eating comparable amounts of α-carotene, β-cryptoxanthin and β-carotene foods resulted in 55% greater α-carotene (95% CI 35, 90) and 686% higher β-cryptoxanthin (95% CI 556, 1016) concentrations than β-carotene in blood. This suggests differences in the apparent bioavailability of α-carotene and β-cryptoxanthin and even larger differences with β-cryptoxanthin, greater than that of β-carotene. Four fruits (tomato, orange, tangerine, red pepper) and two vegetables (carrot, spinach) are the main contributors to their dietary intake (>50%) in Europeans.

Biomarker-based validity of a food frequency questionnaire estimating intake in Brazilian children and adolescents

This study evaluated the validity of nutrient and food group intakes estimated by an FFQ against biomarkers. A 71-item semiquantitative FFQ was administered to 210 Brazilian children and adolescents aged 9-13 years. Intakes were correlated with biomarkers in plasma and red blood cells. Correlations between nutrients and their biomarkers were presented for animal protein, myristic acid (C14:0), EPA, DHA, β-carotene, folate, and vitamins B3, B5 and B6. Food groups and biomarkers were correlated as follows: fish products with EPA and DHA; milk and dairy with C14:0, pyridoxal 5'-phosphate and vitamin B12; total vegetables and dark green and orange vegetables with β-carotene; 5-methyltetrahydrofolate with green vegetables; and flour products with para-aminobenzoylglutamic acid. This FFQ is a valid tool for ranking Brazilian children and adolescents according to their intake of several nutrients and food groups.

Daily steps and diet, but not sleep, are related to mortality in older Australians

OBJECTIVES

Supporting healthy ageing is a key priority worldwide. Physical activity, diet quality and sleep are all associated with health outcomes, but few studies have explored their independent associations with all-cause mortality in an older population in the same model. The study aim was to examine associations between step-count, self-reported diet quality, restless sleep, and all-cause mortality in adults aged 55-85 years.

DESIGN

A prospective cohort study of adults in Newcastle, New South Wales, Australia.

METHOD

Data were from 1697 participants (49.3% women; baseline mean age 65.4 ± 7.1 years). Daily steps (measured by pedometer), diet quality (from a modified Australian Recommended Food Score), and frequency of restless sleep (by self-report) were assessed in relation to all-cause mortality using Cox proportional hazard regression with adjustment for sex, age, household income and smoking. Baseline data were collected between January 2005 and April 2008, and last follow-up was in March 2017 (median follow-up 9.6 years).

RESULTS

Higher step count (HR: 0.93, 95%CI: 0.88-0.98 per 1000-step increment) and higher diet quality (HR: 0.86, 95%CI: 0.74-0.99 per 8-point increment in diet quality score) were associated with reduced mortality risk. Restless sleep for ≥3 nights/week was not associated with mortality risk (HR: 1.03, 95%CI: 0.78-1.39). Sensitivity analyses, adjusting for chronic disease and excluding deaths <1 year after baseline, did not change these estimates.

CONCLUSIONS

Increased daily steps and consumption of a greater variety of nutrient-dense foods every week would result in substantial health benefits for older people. Future research should include a greater variety of sleep measures.

Associations between self-reported vegetable and fruit intake assessed with a new web-based 24-h dietary recall and serum carotenoids in free-living adults: a relative validation study

The aim of the present study was to assess the relative validity of a new web-based 24-h dietary recall (R24W) in terms of vegetable and fruit (VF) intake assessment using serum carotenoid concentrations as reference biomarkers. A total of seventy-four women and seventy-three men (mean age 47·5 (sd 13·3) years; mean BMI 25·5 (sd 4·4) kg/m2) completed the R24W four times to assess their VF intake. Serum carotenoids were obtained from 12-h fasted blood samples and measured by HPLC. Raw and de-attenuated partial Spearman's correlations were performed to determine how usual vegetable and/or fruit intake was associated with serum carotenoids. Relevant confounders were selected using a stepwise regression analysis. Finally, cross-classification was used to determine agreement between intake of VF and serum carotenoids. Intake of total dietary carotenoids was significantly associated (r 0·40; P < 0·01) with total serum carotenoids (without lycopene). Total VF intake was also associated with total serum carotenoid concentrations without lycopene (r 0·44; P < 0·01). HDL-cholesterol, waist circumference and age were identified as confounders in the association between total VF intake and total serum carotenoids (without lycopene). De-attenuated partial correlation adjusted for these confounders increased the associations between dietary carotenoids and total serum carotenoids without lycopene (r 0·49; P < 0·01) and between total VF intake and total serum carotenoids without lycopene (r 0·48; P < 0·01). Almost 80 % of respondents were classified in the same or the adjacent quartile for total VF intake and total serum carotenoids without lycopene, while less than 6 % were classified in the opposite quartile. Overall, these observations support the appropriateness of the R24W to assess the dietary intake of VF.

Serum and Erythrocyte Biomarkers of Nutrient Status Correlate with Short-Term Α-Carotene, Β-Carotene, Folate, and Vegetable Intakes Estimated by Food Frequency Questionnaire in Military Recruits

OBJECTIVE

Food frequency questionnaires (FFQs) estimate habitual dietary intake and require evaluation in populations of interest in order to determine accuracy. Thus, the purpose of this study was to determine agreement between circulating biomarkers and FFQ estimated dietary intake in a military population consuming all meals in a dining facility over 12 weeks.

METHODS

2014 Block FFQs were administered and fasted blood samples were drawn to assess nutritional biomarkers at the end of a 12-week training period in male (n = 141) and female (n = 125) Marine recruits undergoing initial military training. FFQ estimates of alpha- and beta-carotene, folate, and fruit and vegetable intake and circulating concentrations of serum alpha- and beta-carotene and serum and erythrocyte folate were measured. Partial correlations were used in the full model, and weighted kappa coefficients were used to determine agreement between ranking quartiles of dietary intake estimates with corresponding biomarker status quartiles.

RESULTS

Serum and dietary intake of alpha-carotene were positively associated in males (p = 0.009) and females (p < 0.001), as was serum and intake of beta-carotene (males, p = 0.002; females, p < 0.001). Alpha-carotene was positively associated with vegetable intake in males (p = 0.02) and beta-carotene with vegetable intake in females (p = 0.003). Serum folate in males (p = 0.002) and erythrocyte folate in females (p = 0.02) were associated with dietary folate intake. In females, the relationships between biomarker and dietary estimates yielded significant kappa coefficients. In males, a significant kappa coefficient was observed for erythrocyte folate and dietary intake of folate only. The kappa coefficient for serum and estimated intake of beta-carotene was not significant in males.

CONCLUSION

Twelve-week habitual intake of alpha-and beta-carotene and folate were correlated with circulating biomarkers in a military training population. The 2014 Block FFQ was able to accurately rank females into quartiles of nutrient status based on intake, while males were ranked less accurately than females.

Inflammation mediates the association between fatty acid intake and depression in older men and women

Antioxidants and fatty acids are associated with depression and inflammation, and inflammation appears to predict depression risk; hence, the associations between these nutrients and depression may be mediated by inflammation. We hypothesized that inflammatory markers interleukin (IL)-6 and C-reactive protein (CRP) mediate the associations between antioxidant and fatty acid intakes, and depression. Participants were from the Hunter Community Study, a longitudinal cohort of adults aged 55-85 years. Dietary intake was assessed using the Older Australian's Food Frequency Questionnaire. Fasting blood samples were drawn for analysis of nutrient and inflammatory biomarkers. Depressive symptoms were assessed using the 20-item Center for Epidemiologic Studies-Depression scale at baseline and at 5-year follow-up. Linear mixed models were used to investigate longitudinal associations between dietary intakes and depression, and mediation analyses were carried out to determine if IL-6 and/or CRP were the mediators. Analyses were conducted on men and women separately and adjusted for potential confounders. Fruit and monounsaturated fat intakes were negatively associated with depression, whereas total fat and saturated fat intakes were positively associated with depression in both sexes. Omega-3 polyunsaturated fat was inversely associated with depression in men only. IL-6 was a significant mediator of the association between fruits with low carotenoid content and depression in women. CRP significantly mediated the relationship between total fat, saturated fat, and monounsaturated fat intakes and depression in women, and saturated fat intake and depression in men. Our findings raise the possibility that the association between fatty acid intake and depression is partially mediated by inflammatory markers.