Anette Bysted

Carotenoids: Actual knowledge on food sources, intakes, stability and bioavailability and their protective role in humans

Carotenoids are one of the major food micronutrients in human diets and the overall objective of this review is to re-examine the role of carotenoids in human nutrition. We have emphasized the attention on the following carotenoids present in food and human tissues: beta-carotene, beta-cryptoxanthin, alpha-carotene, lycopene, lutein and zeaxanthin; we have reported the major food sources and dietary intake of these compounds. We have tried to summarize positive and negative effects of food processing, storage, cooking on carotenoid content and carotenoid bioavailability. In particular, we have evidenced the possibility to improve carotenoids bioavailability in accordance with changes and variations of technology procedures.

Coenzyme Q10 in the diet-daily intake and relative bioavailability

The coenzyme Q10 content of the average Danish diet was estimated from consumption data and from analysis of food items to be 3-5 mg coenzyme Q10 per day, primarily derived (64% of the total) from meat and poultry. To investigate if coenzyme Q10 was absorbed to any significant degree from a food item, a randomized cross-over study with single doses of coenzyme Q10 (30 mg/person), administered either as a meal or as capsules, was carried out in healthy subjects. The serum coenzyme Q10 concentration increased significantly, and the maximum concentrations did not differ significantly for the two forms of administration. The study indicates that coenzyme Q10 is present in food items and absorbed to a significant degree. Thus, dietary coenzyme Q10 may contribute to the plasma coenzyme Q10 concentration.

25-hydroxyvitamin D3 affects vitamin D status similar to vitamin D3 in pigs--but the meat produced has a lower content of vitamin D.

In food databases, the specific contents of vitamin D3 and 25-hydroxyvitamin D3 in food have been implemented in the last 10 years. No consensus has yet been established on the relative activity between the components. Therefore, the objective of the present study was to assess the relative activity of 25-hydroxyvitamin D3 compared to vitamin D3. The design was a parallel study in pigs (n 24), which from an age of 12 weeks until slaughter 11 weeks later were fed approximately 55 microg vitamin D/d, as vitamin D3, in a mixture of vitamin D3 and 25-hydroxyvitamin D3, or 25-hydroxyvitamin D3. The end-points measured were plasma 25-hydroxyvitamin D3, and in the liver and loin the content of vitamin D3 and 25-hydroxyvitamin D3. Vitamin D3 and 25-hydroxyvitamin D3 in the feed did not affect 25-hydroxyvitamin D3 in the plasma, liver or loin differently, while a significant effect was shown on vitamin D3 in the liver and loin (P < 0.001). 25-Hydroxyvitamin D3 in the plasma, liver and loin significantly correlates with the sum of vitamin D3 and 25-hydroxyvitamin D3 in the feed (P < 0.05). Therefore, 25-hydroxyvitamin D3 should be regarded as having the same activity as vitamin D3 in food databases. Sole use of 25-hydroxyvitamin D3 as a vitamin D source in pig feed will produce liver and meat with a negligible content of vitamin D3, while an increased content of vitamin D3 in the feed will produce liver and meat with increased content of both vitamin D3 and 25-hydroxyvitamin D3.

Evaluation of Web-based Dietary Assessment Software for Children: comparing reported fruit, juice and vegetable intakes with plasma carotenoid concentration and school lunch observations

Web-based Dietary Assessment Software for Children (WebDASC) was developed to estimate dietary intake in a school meal intervention study among 8- to 11-year-old Danish children. The present study validates self-reported fruit, juice and vegetable (FJV) intakes in 8- to 11-year-old children by comparing intake with plasma carotenoid concentration, and by comparing the reported FJV intake to actually eaten FJV, as observed by a photographic method. A total of eighty-one children, assisted by parents, reported their diet for seven consecutive days. For the same five schooldays as they reported their diet, the childrens school lunch was photographed and weighed before and after eating. In the week after the diet reporting, fasting blood samples were taken. Self-reported intake of FJV and estimated intake of carotenoids were compared with plasma carotenoid concentration. Accuracy of self-reported food and FJV consumption at school lunch was measured in terms of matches, intrusion, omission and faults, when compared with images and weights of lunch intake. Self-reported intake of FJV was significantly correlated with the total carotenoid concentration (0·58) (P< 0·01). Fruit and juice consumption showed higher correlations than vegetables with plasma carotenoid concentration (0·38 and 0·42 v. 0·33) (P< 0·01). A total of 82 % of the participants fell into the same or adjacent quartiles when cross-classified by FJV intake and carotenoids biomarkers. WebDASC attained 82 % reporting matches overall and a higher percentage match for reporting fruits compared with beverages. The present study indicated that WebDASC can be used to rank 8- to 11-year-old Danish children according to their intake of FJV overall and at school meals.

Intake of ruminant trans fatty acids in the Danish population aged 1-80 years

Objective:To estimate the intake of ruminant trans fatty acids (TFA) in the Danish population aged 1–80 years.Design:Descriptive study.Subjects:A sex- and age-stratified random sample drawn from the Danish Civil Registration System. A total of 3098 participants (51% female) aged 1–80 years were included. The participation was 66%.Dietary information:A 7-day dietary record.Results:The estimated median intake of ruminant TFA was 1.4 g/day with the 80% central range being from 0.9 to 2.1 among children aged 1–6 years and 1.6 g/day (1.0–2.4) among children aged 7–14 years. The median TFA intake was 1.8 g/day (0.9–2.9) among adults aged 15–29 years and among adults aged 30–80 years. The intake expressed as percentage of energy intake was 0.8, 0.6, 0.7, and 0.7, respectively. Dairy products were the main source of ruminant TFA.Conclusions:The median intake of ruminant TFA in the Danish population aged 1–80 years is estimated to be 1.7 g/day (0.9–2.7), corresponding to 0.7% of energy intake (0.5–1.0), with dairy products being the main source of ruminant TFA.Sponsorship:The Danish Heart Foundation (Grants 02-2-9-8-22010 and 03-2-9-4-22087) and the Female Researchers in Joint Action (FREJA) programme from the Danish Medical Research Council.

Effects of organic and conventional growth systems on the content of carotenoids in carrot roots, and on intake and plasma status of carotenoids in humans.

BACKGROUND The demand for organic food products has increased during the last decades due to their probable health effects, among others. A higher content of secondary metabolites such as carotenoids in organic food products has been claimed, though not documented, to contribute to increased health effects of organic foods. The aim was to study the impact of organic and conventional agricultural systems on the content of carotenoids in carrots and human diets. In addition, a human cross-over study was performed, measuring the plasma status of carotenoids in humans consuming diets made from crops from these agricultural systems. RESULTS The content of carotenoids in carrot roots and human diets was not significantly affected by the agricultural production system or year, despite differences in fertilisation strategy and levels. The plasma status of carotenoids increased significantly after consumption of the organic and conventional diets, but no systematic differences between the agricultural production systems were observed. CONCLUSION The expected higher content of presumed health-promoting carotenoids in organic food products was not documented in this study.

Effect of dietary fatty acids on the postprandial fatty acid composition of triacylglycerol-rich lipoproteins in healthy male subjects.

Objective: The aim of the present study was to investigate the effect of trans-18:1 isomers compared to other fatty acids, especially saturates, on the postprandial fatty acid composition of triacylglycerols (TAG) in chylomicrons and VLDL.Design: A randomised crossover experiment where five interesterified test fats with equal amounts of palmitic acid (P fat), stearic acid (S fat), trans-18:1 isomers (T fat), oleic acid (O fat), or linoleic acid (L fat) were tested.Subjects: A total of 16 healthy, normolipidaemic males (age 23±2 y) were recruited.Interventions: The participants ingested fat-rich test meals (1 g fat per kg body weight) and the fatty acid profiles of chylomicron and VLDL TAG were followed for 8 h.Results: The postprandial fatty acid composition of chylomicron TAG resembled that of the ingested fats. The fatty acids in chylomicron TAG were randomly distributed among the three positions in accordance with the distributions in test fats. Calculations of postprandial TAG concentrations from fatty acid data revealed increasing amounts up to 4 h but lower response curves (IAUC) for the two saturated fats in accordance with previous published data. The T fat gave results comparable to the O and L fats. The test fatty acids were much less reflected in VLDL TAG and there was no dietary influence on the response curves.Conclusions: The fatty acid composition in the test fats as well as the positional distributions of these were maintained in the chylomicrons. No specific clearing of chylomicron TAG was observed in relation to time.Sponsorship: Danish Research Development Program for Food Technology.

Evaluation of flavonoids and enterolactone in overnight urine as intake biomarkers of fruits, vegetables and beverages in the Inter99 cohort study using the method of triads.

Since collection of 24 h urine samples is very time consuming and difficult to obtain, epidemiological studies typically only obtain spot urine samples. The aim of the present study was to evaluate whether flavonoids and enterolactone in overnight urine could substitute flavonoids and enterolactone in 24 h urine as an alternative and more feasible biomarker of fruit, vegetable and beverage intake. A total of 191 individuals in the Inter99 cohort in Denmark completed the validation study. Concentrations of nine urinary flavonoid aglycones (quercetin, isorhamnetin, tamarixetin, kaempferol, hesperetin, naringenin, eriodictyol, phloretin and apigenin) and enterolactone were determined in overnight and 24 h urine samples, and their validity as biomarkers of fruit, vegetable and beverage intake was evaluated in relation to two independent reference methods (Inter99 FFQ data and plasma carotenoids) by using the method of triads. The intakes of fruit, juice, vegetables and tea reported in the FFQ were reflected by the flavonoid biomarker both in overnight and 24 h urine samples. Validity coefficients for the flavonoid biomarker in overnight urine ranged from 0·39 to 0·49, while the corresponding validity coefficients for the biomarker in 24 h urine ranged from 0·43 to 0·66. Although the validity coefficients were lower for overnight urine than for the 24 h urine flavonoid biomarker, they were still of acceptable magnitude. In conclusion, the results indicate that flavonoids and enterolactone in overnight urine samples may be used as a more feasible biomarker than 24 h urine for the assessment and validation of fruit, juice, vegetable and tea intakes in epidemiological studies.

Vitamin D status assessed by a validated HPLC method: within and between variation in subjects supplemented with vitamin D3

Objective. The aim of this study was to develop and validate a high‐pressure liquid chromatography (HPLC) method for assessing vitamin D status as 25‐hydroxyvitamin D2 (S‐25OHD2) and 25‐hydroxyvitamin D3 (S‐25OHD3) in serum. Material and methods. We assessed the within‐ and between‐subject variation of vitamin D status in serum samples from four different dietary intervention studies in which subjects (n = 92) were supplemented with different doses of vitamin D3 (5–12 µg/day) and for different durations (4–20 months). Results. The HPLC method was applicable for 4.0–200 nmol S‐25OHD/L, while the within‐day and between‐days variations were 3.8 % and 5.7 %, respectively. There was a concentration‐dependent difference between results obtained by a commercial radioimmunoassay and results from the HPLC method of −5 to 20 nmol 25OHD/L in the range 10–100 nmol 25OHD/L. The between‐subject variation estimated in each of the four human intervention studies did not differ significantly (p = 0.55). Hence, the pooled standard deviation was 15.3 nmol 25OHD3/L. In the studies with 6–8 samplings during 7–20 months of supplementation, the within‐subject variation was 3.9–7.2 nmol 25OHD3/L, while vitamin D status was in the range 47–120 nmol/L. Conclusions. The validated HPLC method was applied in samples from human intervention studies in which subjects were supplemented with vitamin D3. The estimated standard deviation between and within subjects is useful in the forthcoming decision on setting limits for optimal vitamin D status.

Intestinal absorption of coenzyme Q10 administered in a meal or as capsules to healthy subjects

Abstract A randomized cross-over study by supplementation with single doses of coenzyme Q 10 (30 mg/person), administered either as a meal consisting of cooked pork heart or as 30 mg coenzyme Q 10 capsules was performed to investigate the bioavailability of dietary coenzyme Q 10 in humans. The increase in serum coenzyme Q 10 concentration was used as an index of the absorption, and reached a maximum six hours after the ingestion of either meal or capsules. Following intake of coenzyme Q 10 capsules, the serum coenzyme Q 10 concentrations increased significantly (p 10 from 0.97 to 1.44 mg/L. The difference between the absorption from meal and capsules was not significant. This study indicates that coenzyme Q 10 present in the diet may contribute significantly to plasma coenzyme Q 10 concentrations in humans.