Examining Potential Modifiers of Human Skin and Plasma Carotenoid Responses in a Randomized Trial of a Carotenoid-Containing Juice Intervention

BACKGROUND

Skin carotenoid measurements are emerging as a valid and reliable indicator of fruit and vegetable intake and carotenoid intake. However, little is known about the extent to which skin carotenoid responsivity to dietary changes differs based on demographic and physiologic characteristics.

OBJECTIVES

This study examined potential effect modifiers of skin carotenoid and plasma carotenoid responses to a carotenoid-rich juice intervention.

METHODS

We leveraged data from 2 arms of a 3-site randomized controlled trial of a carotenoid-containing juice intervention (moderate dose = 6 ounces juice, 4 mg total carotenoids/d, high dose = 12 ounces juice, 8 mg total carotenoids/d) (n = 106) to examine effect modification by age, self-categorized race/ethnicity, biological sex, baseline body fat, body mass index, skin melanin, skin hemoglobin, skin hemoglobin saturation, skin coloration, sun exposure, and baseline intake of carotenoids from foods. Skin carotenoid concentrations were assessed using pressure-mediated reflection spectroscopy (Veggie Meter), and plasma carotenoid concentrations were measured using high-performance liquid chromatography.

RESULTS

In bivariate analyses, among the high-dose group (8 mg/d), those of older age had lower skin carotenoid responsiveness than their younger counterparts, and those with greater hemoglobin saturation and lighter skin had higher skin carotenoid score responsiveness. In the moderate-dose group (4 mg/d), participants from one site had greater plasma carotenoid responsiveness than those from other sites. In multivariate analyses, participants with higher baseline skin carotenoids had smaller skin carotenoid responses to both moderate and high doses.

CONCLUSIONS

Changes in skin carotenoid scores in response to interventions to increase fruit and vegetable intake should be interpreted in the context of baseline skin carotenoid scores, but other variables (e.g., self-categorized race/ethnicity, biological sex, baseline body fat, body mass index, skin melanin, and sun exposure) do not significantly modify the effect of carotenoid intake on changes in skin carotenoid scores. This trial was registered at clinicaltrials.gov as NCT04056624.

Evaluation of a Commercial Device Based on Reflection Spectroscopy as an Alternative to Resonance Raman Spectroscopy in Measuring Skin Carotenoid Levels: Randomized Controlled Trial

Resonance Raman spectroscopy (RRS) has been used as a reference method for measuring skin carotenoid levels (SCL), which indicate vegetable and fruit intake. However, RRS is not an easy-to-use method in SCL measurement due to its complicated implementation. In this study, a commercial spectrophotometer based on reflection spectroscopy (RS), which is relatively simple and inexpensive, was evaluated to confirm usability compared with RRS in measuring SCL. To investigate the agreement between RS and RRS, eighty participants were randomly assigned to a high-carotenoid diet group (21 mg/day of total carotenoids) or a control-carotenoid diet group (14 mg/day of total carotenoids) during a 6-week whole-diet intervention period and a 4-week tracking period. Strong correlations between the RS and RRS methods were observed at baseline (r = 0.944) and the entire period (r = 0.930). The rate of SCL increase was similar during the diet intervention; however, the initiation of the SCL decrease in RS was slower than in RRS during the tracking period. To confirm the agreement of RS and RRS from various perspectives, new visualization tools and indices were additionally applied and confirmed the similar response patterns of the two methods. The results indicate that the proposed RS method could be an alternative to RRS in SCL measurements.

Fruit and vegetable liking and intake among college students: a cross-sectional study

ObjectiveThis study examined the liking of fruits and vegetables among college students and the relationship between skin carotenoid levels and liking of fruits and vegetables. Participants: Sixty-six undergraduate students enrolled at a university in the southeastern United States participated in this study beginning August 2019. Methods: Skin carotenoid levels were measured using the Veggie Meter® reflection spectroscopy device. Liking of individual fruits and vegetables was measured using a hedonic general Labeled Magnitude Scale. Results: There were significant differences in mean skin carotenoid levels by year of study and age group. Students had a very strong liking for potatoes and pineapple. Veggie Meter scores and overall liking for fruits and vegetables were positively correlated. Conclusions: In order to encourage the consumption of fruits and vegetables, preferences for specific fruits and vegetables as well as accessibility should be considered to better serve and accommodate college students.

Validation of resonance Raman spectroscopy-measured skin carotenoid status as a biomarker for fruit and vegetable intake in Korean adults

Blood carotenoid concentration measurement is considered the gold standard for fruit and vegetable (F&V) intake estimation; however, this method is invasive and expensive. Recently, skin carotenoid status (SCS) measured by optical sensors has been evaluated as a promising parameter for F&V intake estimation. In this cross-sectional study, we aimed to validate the utility of resonance Raman spectroscopy (RRS)-assessed SCS as a biomarker of F&V intake in Korean adults. We used data from 108 participants aged 20-69 years who completed SCS measurements, blood collection, and 3-d dietary recordings. Serum carotenoid concentrations were quantified using high-performance liquid chromatography, and dietary carotenoid and F&V intakes were estimated via 3-d dietary records using a carotenoid database for common Korean foods. The correlations of the SCS with serum carotenoid concentrations, dietary carotenoid intake, and F&V intake were examined to assess SCS validity. SCS was positively correlated with total serum carotenoid concentration (r=0.52, 95% confidence interval [CI]=0.36 to 0.64, P<0.001), serum β-carotene concentration (r=0.60, 95% CI=0.47 to 0.71, P<0.001), total carotenoid intake (r=0.20, 95% CI=0.01 to 0.37, P=0.04), β-carotene intake (r=0.30, 95% CI=0.11 to 0.46, P=0.002), and F&V intake (r=0.40, 95% CI=0.23 to 0.55, P<0.001). These results suggest that SCS can be a valid biomarker of F&V intake in Korean adults.

Inter-device concordance of Veggie Meter, a reflection spectroscopy to measure skin carotenoids

The Veggie Meter® (VM) is a refraction spectrometer that detects skin carotenoids. We tested the variability of the two modes (single-scan and averaging modes) of four VMs of three different versions (VM-1, 2, 3, 4) with 92 healthy volunteers. Both the modes exhibited a high intraclass correlation coefficient; however, the averaging mode had a significantly lower coefficient of variance than the single-scan mode. The Bland-Altman analysis showed a systematic error between VM-1 and other three VMs. The actual errors between the VM-1 and the other three VMs in the averaging mode were 7.4, 10.4, and 11.8% of the median of VM scores, but the errors could be reduced to 2.8, 6.3, and 7.0% by compensating VM scores using the regression equations. Averaging mode had higher accuracy than single-scan mode. The reliability of the VMs was validated by the small CV and high ICC. The error was improved using linear regression compensation.

Assessment of Skin Carotenoid Measurement as a Means to Detect Vitamin A Deficiency in Children and Pregnant Women of Nepal

BACKGROUND

Vitamin A deficiency (VAD) is an ongoing public health concern among children and pregnant women in Nepal despite robust national efforts to screen and treat this vision- and life-threatening condition.

OBJECTIVES

This study aimed to evaluate skin carotenoid scores measured using the Veggie Meter as a rapid, noninvasive screening tool for VAD in Nepali children and pregnant women.

METHODS

This comparative cross-sectional study enrolled 164 pregnant women and 168 children (aged 8 to 12 y) from public hospitals in three distinct outlying ecological regions of Nepal (Terai, Hill, and Mountain). The primary outcome assessed whether skin carotenoid status could be a biomarker for VAD. We determined skin carotenoid scores using the Veggie Meter and compared them with serum retinol and total carotenoid concentrations assessed by HPLC. Correlation analysis was used to determine bivariate associations between serum retinol and total carotenoid concentrations, and the Veggie Meter assessed skin carotenoid status. Receiver operating characteristics curves were determined, and a P value <0.05 was considered statistically significant.

RESULTS

We found that 8.5% of pregnant women and 13.0% of children in this study had severe VAD (serum retinol < 200 ng/mL). There were significant correlations between skin carotenoid scores with serum retinol and total carotenoid concentrations among pregnant women and children (r = 0.253-0.530, P ≤ 0.001). The Veggie Meter detected severe VAD with 57.1% sensitivity and 82.7% specificity in pregnant women and 61.9% sensitivity and 75.9% specificity in children.

CONCLUSIONS

Although sensitivity and specificity were moderate for detecting VAD with the Veggie Meter, skin carotenoid assessment using this rapid, noninvasive portable device could still be valuable for high-risk VAD screening in Nepal and similar developing countries with limited access to laboratory measurement of serum vitamin A concentrations.

Reflection Spectroscopy-Assessed Skin Carotenoids Are Sensitive to Change in Carotenoid Intake in a 6-Week Randomized Controlled Feeding Trial in a Racially/Ethnically Diverse Sample

BACKGROUND

Reflection spectroscopy, utilized by the Veggie Meter, is a less-expensive, noninvasive method to quantify skin carotenoids and is a valid approximation of fruit and vegetable (FV) intake. However, it is unknown to what degree Veggie Meter-assessed skin carotenoid score change is responsive to changes in carotenoid intake.

OBJECTIVES

This study aimed to evaluate Veggie Meter-assessed skin carotenoid score response in a 6-wk randomized controlled trial of a carotenoid-containing juice to determine whether the Veggie Meter can be used to detect nutritionally relevant changes in carotenoid intake; and to compare skin and plasma carotenoid responses with the 6-wk trial.

METHODS

In this 6-wk trial, participants (n = 162) who self-identified as one of 4 US racial/ethnic groups (25% Black, 25% Asian, 27% non-Hispanic White, 23% Hispanic) were randomized to a control group, receiving negligible carotenoids (177 mL apple juice/d), moderate-dose group, receiving 4 mg total carotenoids/d (177 mL orange-carrot juice/d), or high-dose group, receiving 8 mg total carotenoids/d (355 mL orange-carrot juice/d). Skin carotenoid score and plasma total carotenoid concentrations (α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein, zeaxanthin) were assessed at baseline, 3 wk, and 6 wk (n = 158 completed the trial). Repeated measures linear models were used to examine skin and plasma carotenoids over time and between groups.

RESULTS

At 6 wk, participants in the high-dose and moderate-dose groups had significantly higher mean skin carotenoid scores [414.0 (SD = 100.6) and 369.7 (SD = 100.3), respectively] compared with those in the control group [305.2 (100.5)]. In the high-dose group, there was a 42% change in skin carotenoids from baseline (mean = 290.4) to a 6-wk follow-up (increase of 123, 123/290 = 42.4%). There was a 61% change in the plasma carotenoids in the high-dose group.

CONCLUSIONS

The Veggie Meter is sensitive to increases in daily carotenoid intake in diverse racial/ethnic groups over 6 wk.

CLINICAL TRIALS REGISTRY NUMBER

This trial was registered at clinicaltrials.gov as ID: NCT04056624. Study URL: https://clinicaltrials.gov/ct2/show/NCT04056624.

Biochemical Validation of a Self-Administered Carotenoid Intake Screener to Assess Carotenoid Intake in Nonobese Adults

Background

Epidemiological studies have demonstrated an association between carotenoid intake and health. However, an accurate measurement of carotenoid intake is challenging. FFQ is the most commonly used dietary assessment method and is typically composed of 100-200 items. However, the greater participant burden that accompanies a more detailed FFQ provides only a marginal gain in accuracy. Therefore, a brief validated carotenoid intake screener is needed.

Objectives

To conduct secondary analysis evaluating the validity of a newly developed 44-item carotenoid intake screener from The Juice Study: Sensitivity of Skin Carotenoid Status to Detect Change in Intake (NCT03202043) against corresponding plasma carotenoid concentrations (primary) and skin carotenoids (secondary) in nonobese Midwestern American adults.

Methods

Healthy adults (n = 83; 25 men and 58 women) aged 18-65 y (mean age, 32 ± 12 y) with a BMI (in kg/m2) of 18.5-29.9 (mean BMI, 25 ± 3) were recruited between 25 April 2018 and 28 March 2019. Participants completed the carotenoid intake screener weekly during the 8-wk parent study. Plasma carotenoid concentrations were assessed at weeks 0, 4, and 8 using HPLC. Skin carotenoids were assessed weekly using pressure-mediated reflection spectroscopy (RS). Correlation matrices from mixed models were used to determine the correlation between carotenoid intake and plasma and skin carotenoids over time.

Results

The total carotenoid intake, as determined by the carotenoid intake screener, correlated with both the plasma total carotenoid concentration (r = 0.52; P < 0.0001) and the RS-assessed skin carotenoid concentration (r = 0.43; P < 0.0001). Correlations between reported intake and plasma concentrations of α-carotene (r = 0.40; P = 0.0002), cryptoxanthin (r = 0.28; P = 0.0113), and lycopene (r = 0.33; P = 0.0022) were also observed.

Conclusions

The results of this study demonstrate an acceptable relative validity of the carotenoid intake screener to assess total carotenoid intake in adults classified as those having a healthy body or those with overweight.

Sensitivity of Pressure-Mediated Reflection Spectroscopy to Detect Changes in Skin Carotenoids in Adults Without Obesity in Response to Increased Carotenoid Intake: A Randomized Controlled Trial

BACKGROUND

The sensitivity of commercially available devices to detect changes in skin carotenoids is not known.

OBJECTIVES

We aimed to determine the sensitivity of pressure-mediated reflection spectroscopy (RS) to detect changes in skin carotenoids in response to increasing carotenoid intake.

METHODS

Nonobese adults were randomly assigned to a control (water; n = 20; females = 15 (75%); mean age: 31 ± 3 (SE) y; mean BMI: 26 ± 1 kg/m²) or one of 3 carotenoid intake levels: 1) LOW - 13.1 mg; n = 22; females = 18(82%); age: 33 ± 3 y; BMI: 25 ± 1 kg/m²; 2) MED - 23.9 mg; n = 22; females = 17 (77%); age: 30 ± 2 y; BMI: 26 ± 1 kg/m²); or 3) HIGH - 31.0 mg; n = 19; females = 9 (47%); age: 33 ± 3 y; BMI: 24 ± 1 kg/m². A commercial vegetable juice was provided daily to ensure that the additional carotenoid intake was achieved. Skin carotenoids (RS intensity [RSI]) were measured weekly. Plasma carotenoid concentrations were assessed at wk 0, 4, and 8. Mixed models were used to test the effect of treatment, time, and their interaction. Correlation matrices from mixed models were used to determine the correlation between plasma and skin carotenoids.

RESULTS

A correlation was observed between skin and plasma carotenoids (r = 0.65; P < 0.001). Skin carotenoids were greater than baseline starting at week 1 in the HIGH (290 ± 20 vs. 321 ± 24 RSI; P ≤ 0.01), week 2 in the MED (274 ± 18 vs. 290 ± 23 RSI; P ≤ 0.03), and week 3 in the LOW (261 ± 18 vs. 288 ± 15 RSI; P ≤ 0.03). Compared with control, differences in skin carotenoids were observed starting at week 2 in the HIGH ([268 ± 16 vs. 338 ± 26 RSI; P ≤ 0.01] except for week 3 [287 ± 20 vs. 335 ± 26 RSI; P = 0.08]) and week 6 in the MED (303 ± 26 vs. 363 ± 27 RSI; P ≤ 0.03). No differences were observed between the control and LOW.

CONCLUSIONS

These findings demonstrate that RS can detect changes in skin carotenoids in adults without obesity when daily carotenoid intake is increased by 13.1 mg for a minimum of 3 wk. However, a minimum difference in intake of 23.9 mg of carotenoids is needed to detect group differences. This trial was registered at ClinicalTrials.gov as NCT03202043.

Pressure-Mediated Reflection Spectroscopy Criterion Validity as a Biomarker of Fruit and Vegetable Intake: A 2-Site Cross-Sectional Study of 4 Racial or Ethnic Groups

BACKGROUND

Valid biomarkers of fruit and vegetable (FV) intake are needed for field-based nutrition research.

OBJECTIVES

To examine criterion-related validity of pressure-mediated reflection spectroscopy as a proxy measure of FV intake, using plasma carotenoids and self-reported FV and carotenoid intake as primary and secondary criterion measures, respectively.

METHODS

Healthy adults 18-65 y of age, self-identifying as African American/black (n = 61), Asian (n = 53), white (n = 70), or Hispanic (n = 29), in North Carolina and Minnesota were recruited. Skin carotenoids were assessed via pressure-mediated reflection spectroscopy (Veggie Meter), skin melanin via spectrophotometer, and total plasma carotenoid concentration by HPLC-photodiode array detection. Self-reported carotenoid and FV intake was assessed using a semiquantitative FFQ. Relations between skin carotenoids, plasma carotenoids, FV, and carotenoid intake, with differences by race or ethnicity, age, sex, weight status, cholesterol, and melanin index, were examined by bivariate correlations and adjusted multivariate linear regressions.

RESULTS

The overall unadjusted correlation between skin and total plasma carotenoids was r = 0.71 and ranged from 0.64 (non-Hispanic black) to 0.80 (Hispanic). Correlations between skin carotenoids and self-reported FV intake ranged from 0.24 (non-Hispanic black) to 0.53 (non-Hispanic white), with an overall correlation of r = 0.35. In models adjusted for age, sex, racial or ethnic group, and BMI, skin carotenoids were associated with plasma carotenoids (R2 = 0.55), FV (R2 = 0.17), and carotenoid intake (R2 = 0.20). For both plasma carotenoid and FV measures, associations with skin carotenoids did not vary by race, but these relations did differ by skin melanin-those with lower melanin had a lower correlation between skin and plasma carotenoids.

CONCLUSIONS

Reflection spectroscopy-assessed skin carotenoids may be a reasonable alternative to measurement of plasma carotenoids, a biomarker used to approximate FV intake.

Relationships between Skin Carotenoid Levels and Metabolic Syndrome

Carotenoids have potential antioxidant and anti-inflammatory effects; their protective roles are of particular interest in the pathogenesis of metabolic syndrome (MetS). The reflection spectroscopy method has been recently developed to noninvasively measure skin carotenoid (SC) levels, which highly correlates with serum concentration of carotenoids. The relationship between SC levels and metabolic syndrome has been investigated. We aimed to identify the differences in patient characteristics and SC levels between participants with and without MetS in a large health examination population. In addition, the relationships between SC levels and various clinical parameters related to MetS were investigated. SC levels were measured using a reflection spectroscopy. A total of 1812 Japanese participants (859 male, 953 female; mean age ± standard deviation (SD), 57.8 ± 11.0 years) comprised the study population, i.e., participants with MetS (n = 151) and those without MetS (n = 1661). Multivariate logistic regression analysis was performed to identify variables associated with MetS. Compared to controls (377.3 ± 122.8), SC indices were significantly lower in patients with MetS (340.7 ± 112.5, p = 0.0004). Multivariate models also suggested that lower SC was significantly associated with MetS after adjustment for age, sex, smoking habit, and other potential risk factors for MetS. Furthermore, male gender (p < 0.0001), smoking habit (p < 0.0001) and worse lipid profiles (i.e., serum triglyceride (r = -0.1039, p < 0.0001), high-density lipoprotein (r = 0.1259, p < 0.0001), and usage of hypolipidemic agents (p = 0.0340)) were significantly associated with lower SC levels. The current study indicated that lower SC levels were significantly associated with MetS. This study highlights the antioxidant capacity of carotenoids in patients with MetS and the clinical utility of non-invasive and cost-effective SC measurement to detect participants who are at risk of developing MetS in a large population.

Changes in Parent and Child Skin Carotenoids, Weight, and Dietary Behaviors over Parental Weight Management

(1) The objective was to determine changes in parent-child (ages 7-18) dyad skin carotenoids spanning parental participation in a medical weight management program (WMP), and associations with parent BMI, child BMIz, fruit/vegetable intake, and family meals and patterns. (2) The study design was a longitudinal dyadic observational study with assessment at WMP initiation, mid-point (3-months), and conclusion (6-months). Twenty-three dyads initiated the study, 16 provided assessments at 3 months, and 11 at program conclusion. Associations between parent and child carotenoids (dependent variables) and parent BMI, child BMIz, increases in fruit/vegetable intake, and family meals and patterns were analyzed using Pearson's correlations and independent samples t-tests. Repeated measures ANOVA assessed changes in weight status and carotenoids. (3) Parents experienced significant declines in BMI and skin carotenoid levels over 6 months. Parent and child carotenoids were correlated at each assessment. At initiation, parent BMI and carotenoids were inversely correlated, child carotenoids were associated with increased family meals, and never consuming an evening fast food or restaurant meal were associated with increased parent and child carotenoids. (4) Results demonstrate skin carotenoids are strongly correlated within dyads and may be associated with lower parental BMI and positive family meal practices.

Using the Veggie Meter in Elementary Schools to Objectively Measure Fruit and Vegetable Intake: A Pilot Study

Self-reported fruit and vegetable (FV) consumption in children has limitations that could be overcome with objective measures that are easy to implement. The Veggie Meter (VM) is a non-invasive portable device that measures skin carotenoid levels, a concentration biomarker of usual FV intake. While VM has been used to measure FV consumption in adults, few studies have explored its use in elementary school settings. Designing research studies using the VM with elementary school-age children requires an understanding of how well this device can be used in a school setting and of the distribution of VM scores in this population. We used VM to measure skin carotenoids in a diverse sample of 143 elementary school children who also answered commonly asked questions about consumption frequency of FV the previous day. Multivariable regression was used to assess the independent association of demographic variables with VM scores. VM scores were also compared with student-reported FV intake. There was a weak but statistically significant correlation between reported frequency of total vegetable consumption the previous day and observed VM scores (r = 0.174, p = 0.042). This study provides an example of the successful use of the VM in a school setting to collect an objective measure of FV intake and provides important description of data that can inform future studies.

Wolfberry (Lycium barbarum) Consumption with a Healthy Dietary Pattern Lowers Oxidative Stress in Middle-Aged and Older Adults: A Randomized Controlled Trial

Incorporating zeaxanthin-rich wolfberry (Lycium barbarum) into a healthy dietary pattern may augment its antioxidant potential. The present 16-week, parallel design randomized controlled trial aimed to investigate the impact of adhering to a healthy dietary pattern, either with or without whole dried wolfberry (15 g/d) on oxidative stress status (plasma malondialdehyde and 8-iso-prostaglandin F2α) in middle-aged and older adults. Changes to carotenoids status (plasma and skin carotenoids) and body composition were further evaluated to explore potential mechanisms which underlie the antioxidant properties of wolfberry. Plasma 8-iso-prostaglandin F2α, plasma zeaxanthin and skin carotenoids status were significantly raised in the wolfberry consuming group (n = 22; p < 0.05) compared to the control group which showed no changes (n = 18). Likewise in the wolfberry group only, inverse association was observed between the change values of plasma zeaxanthin and plasma 8-iso-prostaglandin F2α (−0.21 (−0.43, 0.00) ng/µmol, regression coefficient (95% CI); p = 0.05). Wolfberry consumption with a healthy dietary pattern may serve as a dietary strategy to attenuate lipid peroxidation among middle-aged and older adults who are at a heightened risk of oxidative stress induced age-related disorders. The antioxidant properties of wolfberry may be attributed to its rich zeaxanthin content.

A meta-analysis of studies examining associations between resonance Raman spectroscopy-assessed skin carotenoids and plasma carotenoids among adults and children

CONTEXT

No meta-analyses appeared to have been conducted to examine overall correlations between resonance Raman spectroscopy (RRS)-assessed skin carotenoids and plasma/serum carotenoids.

OBJECTIVE

To review the available literature and quantify the association between RRS-assessed skin carotenoids and plasma/serum carotenoids via a meta-analysis of observational studies.

DATA SOURCES

To identify relevant publications, we searched the PubMed, Embase, CINAHL, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, ProQuest, and Scopus databases in April 2020 for items combining 3 concepts: Raman spectroscopy, skin, and plasma or serum.

DATA EXTRACTION

Criteria for inclusion were publication in a peer-reviewed journal between 1990 and 2020, available in English language, and results reported as a baseline Pearson correlation coefficient. In teams of 2, the researchers independently reviewed titles and abstracts of 2212 nonduplicate papers with initial screening yielding 62 papers for full-text review, of which 15 were deemed eligible for inclusion.

DATA ANALYSIS

A random-effects model in R (version 4.0.0) "meta" package was used to analyze the correlation between RRS-assessed skin and plasma/serum carotenoids. A subgroup analysis was conducted for studies involving adults and children, respectively.

CONCLUSIONS

The 15 studies included 1155 individuals: 963 adults and 192 children. One study included children and adults. The random-effects model yielded an overall correlation of 0.68 (95%CI, 0.61-0.74; I2 = 74%; P < 0.01). The results were similar when grouped by adults and children. Among 963 adults, the correlation in the random-effects model was 0.69 (95%CI, 0.61-0.75; I2 = 78%; P < 0.01). Among 192 children, the correlation in the random-effects model was 0.66 (95%CI, 0.52- 0.77; I2 = 55%; P = 0.06). Overall, there was a positive, statistically significant correlation between RRS-assessed skin carotenoids and plasma/serum carotenoids in a pooled meta-analysis of 15 studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO (record number 178835).

Food-Based Science, Technology, Engineering, Arts, and Mathematics (STEAM) Learning Activities May Reduce Decline in Preschoolers' Skin Carotenoid Status

OBJECTIVE

To assess the effectiveness of food-based science, technology, engineering, arts, and mathematics (STEAM) learning activities on preschoolers' liking of 9 target vegetables and objectively-assessed fruit and vegetable (FV) intake.

METHODS

Seven hands-on, food-based STEAM learning activities were implemented to expose children to 9 target vegetables in 3 Head Start preschools (11 classrooms) across North Carolina. Child-reported vegetable liking scores and skin carotenoid status (SCS) were dependent variables collected at baseline, midpoint, and posttest. Adjusted repeated-measures ANOVA was used to examine intervention impact.

RESULTS

A total of 113 children (intervention = 49; comparison = 64) participated. Children were an average age of 3.7 ± 0.57 years at baseline. Mean target vegetable liking scores for the intervention and comparison groups, respectively, were 3.2 ± 0.19 and 3.2 ± 0.17 at baseline, 2.9 ± 0.17 and 3.1 ± 0.15 at midpoint, and 2.8 ± 0.15 and 3.1 ± 0.13 at posttest. A time × group interaction was not significant for target vegetable liking scores. Mean SCS were 268.6 ± 13.24 and 270.9 ± 12.13 at baseline, 271.3 ± 12.50 and 275.6 ± 11.46 at midpoint, and 267.8 ± 11.26 and 229.6 ± 10.32 at posttest for the intervention and comparison groups, respectively. A time × group interaction was significant for SCS (F_1,77 = 3.98; P = 0.02; r = 0.10). Both groups declined from baseline to posttest (intervention = 0.06%; comparison = 15.09%), which occurred after winter break, with a smaller decline observed in the intervention group (P = 0.02).

CONCLUSIONS AND IMPLICATIONS

Food-based STEAM learning activities may present a unique opportunity to affect FV intake while meeting academic standards. More research is needed to understand how liking for familiar FV changes over time and its relationship with consumption. In addition, more implementation research featuring larger sample sizes, teachers as the interventionist, and a longer study duration is needed to confirm the outcomes of food-based STEAM learning observed in the current study and the long-term impact this approach may have on children's' dietary quality.

Fruit and Vegetable Intake Assessed by Repeat 24 h Recalls, but Not by A Dietary Screener, Is Associated with Skin Carotenoid Measurements in Children

Accurate measurement of fruit and vegetable (FV) intake is important for nutrition surveillance and evaluation of dietary interventions. We compared two tools for reporting FV intake to objective measurement of skin carotenoids among children. FV cups/day was assessed by repeated 24 h dietary recalls (24H FV) and the National Cancer Institute’s All-Day Fruit and Vegetable Screener (NCI FV). Skin carotenoids were measured by repeated resonance Raman spectroscopy (RRS) of the palm. FV cups were regressed on RRS scores in unadjusted, field-based, and research-setting models with covariates feasible in each scenario. Data were baseline values from children aged 2–12 years in low-income households enrolled in a healthy eating randomized trial in four U.S. states (n = 177). Twenty-four-hour FV cups were associated with skin carotenoids in all models (p < 0.001) but NCI FV cups were not. Predicted RRS scores for discrete 24H FV cups provide a guide to interpretation of RRS in children (2 cups FV intake ~36,000 RRS units), with the research-setting scenario generally providing the narrowest prediction range (+/−1924). When self-reported data are required, 24 h recalls are more accurate than NCI FV screener data; and, when limited time, resources, or literacy must be considered, RRS scores can be quickly obtained and easily interpreted.

Use of the Veggie Meter® as a tool to objectively approximate fruit and vegetable intake among youth for evaluation of preschool and school-based interventions

BACKGROUND

Reflection spectroscopy is an emerging, non-invasive objective measure used to approximate fruit and vegetable intake. The present study aimed to use a reflection spectroscopy device (the Veggie Meter®, Longevity Link Corporation, Salt Lake City, UT, USA) to assess skin carotenoid status in preschool, middle- and high-school students and to examine associations between skin carotenoids and self-reported dietary intake.

METHODS

In Autumn 2018, we used the Veggie Meter® to assess skin carotenoids and age-appropriate validated dietary assessment measures to approximate fruit and vegetable (FV) intake. Preschool participants completed a previously validated pictorial liking tool using an iPad (Apple Inc., Cupertino, CA, USA). Middle-school participants completed selected questions from the validated School Physical Activity and Nutrition (SPAN) (Michael & Susan Dell Center for Healthy Living, University of Texas, Austin, TX, USA) questionnaire regarding frequency of their FV and beverage intake on the previous day, with additional questions about physical activity. High-school participants' FV intake was assessed using the Fruit and Vegetable Screener (National Cancer Institute, Bethesda, MD, USA). Spearman correlation coefficients were used to determine bivariate associations between measures of dietary intake and Veggie Meter®-assessed skin carotenoid levels.

RESULTS

Mean (SD) Veggie Meter® readings were 266 (82.9), 219 (68.1) and 216 (67.2) among preschool, middle- and high-school students. There was an inverse association between soda intake and Veggie Meter® readings (r = -0.22, P = 0.03) among middle-school students; and a positive association between daily fruit intake and Veggie Meter® readings (r = 0.25, P = 0.06) among high-school students.

CONCLUSIONS

The Veggie Meter® comprises a promising evaluation tool for preschool and school-based nutrition interventions.

Association between Spatial Access to Food Outlets, Frequency of Grocery Shopping, and Objectively-Assessed and Self-Reported Fruit and Vegetable Consumption

Because supermarkets are a critical part of the community food environment, the purpose of this paper is to examine the association between accessibility to the supermarket where participants were surveyed, frequency of shopping at the supermarket, and self-reported and objectively-assessed fruit and vegetable consumption. Accessibility was assessed using Geographic Information Systems (GIS) measured distance and multiple versions of the modified Retail Food Environment Index (mRFEI), including a localized road network buffer version. Frequency of shopping was assessed using self-report. The National Cancer Institute Fruit and Vegetable screener was used to calculate daily servings of fruits and vegetables. Skin carotenoids were assessed using the "Veggie Meter™" which utilizes reflection spectroscopy to non-invasively assess skin carotenoids as an objective measure of fruit and vegetable consumption. Bivariate and multivariable statistics were used to examine the associations in RStudio. There was a positive association between skin carotenoids and the Special Supplemental Nutrition Program for Women Infants and Children (WIC) and mRFEI scores, suggesting that WIC participation and a healthier food environment were associated with objectively-assessed fruit and vegetable consumption (skin carotenoids). Future research should examine these associations using longitudinal study designs and larger sample sizes.

Short-term cactus pear [Opuntia ficus-indica (L.) Mill] fruit supplementation ameliorates the inflammatory profile and is associated with improved antioxidant status among healthy humans

Background

Dietary ingredients and food components are major modifiable factors protecting immune system and preventing the progression of a low-grade chronic inflammation responsible for age-related diseases.

Objective

Our study explored whether cactus pear (Opuntia ficus-indica, Surfarina cultivar) fruit supplementation modulates plasma inflammatory biomarkers in healthy adults. Correlations between inflammatory parameters and antioxidant status were also assessed in parallel.

Design

In a randomised, 2-period (2 weeks/period), crossover, controlled-feeding study, conducted in 28 healthy volunteers [mean age 39.96 (±9.15) years, BMI 23.1 (±1.5) kg/m²], the effects of a diet supplemented with cactus pear fruit pulp (200 g, twice a day) were compared with those of an equivalent diet with isocaloric fresh fruit substitution.

Results

With respect to control, cactus pear diet decreased ( p < 0.05) the pro-inflammatory markers such as tumour necrosis factor-α (TNF-α), interleukin (IL)-1β, interferon-γ (INF)-γ, IL-8, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), whereas it increased ( p < 0.05) the anti-inflammatory marker IL-10. Moreover, the diet decreased ratios between pro-inflammatory biomarkers (CRP, IL-6, IL-8, TNF-α) and anti-inflammatory biomarker (IL-10) ( p < 0.05). Cactus pear supplementation caused an increase ( p < 0.05) in dermal carotenoids (skin carotenoid score, SCS), a biomarker of the body antioxidant status, with correlations between SCS and CRP (r = −0.905, p < 0.0001), IL-8 (r = −0.835, p < 0.0001) and IL-10 (r = 0.889, p < 0.0001).

Conclusions

The presently observed modulation of both inflammatory markers and antioxidant balance suggests cactus pear fruit as a novel and beneficial component to be incorporated into current healthy dietary habits.

Using Skin Carotenoids to Assess Dietary Changes in Students After 1 Academic Year of Participating in the Shaping Healthy Choices Program

OBJECTIVE

To determine whether fourth-grade students participating in the Shaping Healthy Choices Program (SHCP), a school-based nutrition intervention, would change vegetable and carotenoid intake measured by skin carotenoids and dietary intake.

METHODS

Single-group pretest-posttest with a self-selected, convenience sample of students (n = 30) participating in the SHCP, which lasted 1 academic year (9 months). Dietary intake of vegetables and carotenoids as measured by Block food frequency questionnaire and skin carotenoids as measured by Raman spectroscopy were collected at the school preintervention and postintervention.

RESULTS

Reported carotenoid intake decreased by 1.5 mg (P = .05) and skin carotenoids decreased by 2,247.9 RRS intensity units (P = .04). Change in reported intake correlated with change in skin carotenoids (r = .43; P = .02).

CONCLUSIONS AND IMPLICATIONS

The reported decrease in vegetable and carotenoid intake was unanticipated; nevertheless, the RRS measurements confirmed this. RRS data can help evaluate changes in fruit and vegetable intake.