Red blood cell fatty acid patterns from 7 countries: Focus on the Omega-3 index.

Red blood cell (RBC) fatty acid (FA) patterns are becoming recognized as long-term biomarkers of tissue FA composition, but different analytical methods have complicated inter-study and international comparisons. Here we report RBC FA data, with a focus on the Omega-3 Index (EPA + DHA in% of total FAs in RBC), from samples of seven countries (USA, Canada, Italy, Spain, Germany, South Korea, and Japan) including 167,347 individuals (93% of all samples were from the US). FA data were generated by a uniform methodology from a variety of interventional and observational studies and from clinical laboratories. The cohorts differed in size, demographics, health status, and year of collection. Only the Canadian cohort was a formal, representative population-based survey. The mean Omega-3 Index of each country was categorized as desirable (>8%), moderate (>6% to 8%), low (>4% to 6%), or very low (≤4%). Only cohorts from Alaska (treated separately from the US), South Korea and Japan showed a desirable Omega-3 Index. The Spanish cohort had a moderate Omega-3 Index, while cohorts from the US, Canada, Italy, and Germany were all classified as low. This study is limited by the use of cohorts of convenience and small sample sizes in some countries. Countries undertaking national health status studies should utilize a uniform method to measure Omega-3 FA levels.

Magnesium Bioavailability and Tolerability Do Not Differ between Two Supplements with Different Release Properties.

Magnesium (Mg2+) is one of the most frequently supplemented micronutrients. Due to possible gastrointestinal side effects, the European Food Safety Authority and the Institute of Medicine set the upper intake level for Mg2+ from supplements to 250 and 350 mg, respectively. Nevertheless, systematic data concerning the tolerability of Mg2+ supplements are scarce. The aim of the study was to directly compare the bioavailability and tolerability of two 500 mg Mg2+ supplements in a crossover study with duplicate determination. The different release properties were either a direct release (one phase) or a delayed release of the second half (two phases). An open-label, controlled trial with a crossover design, duplicate determination, and one-week washout phases was conducted. The participants ingested the test product after overnight fasting. Blood samples were taken at baseline and after 1, 2, 3, 4, 6, and 8 hours, and urine was collected over a period of 24 hours. The participants were on standardized nutrition during all examination days. There were no significant differences between the test products regarding 24-hour renal Mg2+ excretion and area under the curve of serum Mg2+ levels for 8 hours. Both test products were well tolerated with a very low frequency of gastrointestinal adverse effects and no significant differences between the test products. The Mg2+ bioavailability did not differ between the test products. The supplements examined had the same good tolerability. Both test products are therefore suited to enhance Mg2+ supply without relevant side effects.

Higher prevalence of vitamin D deficiency in German pregnant women compared to non-pregnant women.

PURPOSE: Adequate vitamin D status is crucial for normal development of the fetus and for maternal health. As data on vitamin D status (25-hydroxyvitamin D, 25(OH)D) in German women of different states of pregnancy were not available, this study compared the vitamin D status of German women in all trimesters of pregnancy with that of non-pregnant women. METHODS: The study sample of 858 women (18-45 years) was recruited from April 2013 to March 2015 as a part of the cross-sectional Germany-wide VitaMinFemin study. Serum 25(OH)D levels were determined using chemiluminescence immunoassay. RESULTS: A total of 78.1% of the pregnant women and 53.9% of the non-pregnant women had a vitamin D status <50.0 nmol/L (p < 0.001). In pregnant women, the multivariate binary analysis showed that winter [odds ratio (OR) 13.5], longitude of residence between 6.3°E and 8.9°E (OR 2.0) or 9.0°E and 10.9°E (OR 2.3) and third trimester (OR 2.3) were associated with a higher risk of vitamin D status <25.0 nmol/L, whereas increasing age per one year (OR 0.9) with a lower risk. Compared with non-pregnant women, pregnant women were 3.7 times more likely to have a vitamin D status <25.0 nmol/L. CONCLUSION: A low vitamin D status is prevalent among German pregnant women and should be improved to supply mother and fetus adequately.

Low long chain omega-3 fatty acid status in middle-aged women.

INTRODUCTION: Long-chain (LC) omega-3 fatty acids (n-3 PUFAs) have beneficial effects on cardiovascular health and cognitive decline. Several studies have shown that the LC n-3 PUFA status in women in western countries is low. The aim of this study was to assess the LC n-3 PUFA status in middle-aged German women and to identify variables that might affect the status. MATERIAL AND METHODS: From the nationwide and cross-sectional German VitaMinFemin study, fatty acid levels in the erythrocyte membrane (% of total erythrocyte fatty acids) were ascertained for 446 women (40-60 years). RESULTS: The average omega-3 index (% of eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) of the total study population was 5.49±1.17%. A total of 62.8% of women had a low omega-3 index (>4-6%). The omega-3 index was affected by age and smoking, with slightly higher values in women ≥50 years (p=0.032) and non-smokers (p=0.002). Women taking hormonal contraceptives showed a lower EPA level (p<0.001), a lower ratio of EPA/alpha-linoleic acid (p<0.001) and a higher ratio of DHA/EPA (p<0.001) than women without hormonal contraception. CONCLUSION: The low LC n-3 PUFA status in middle-aged German women (40-60 years) is related to an increased risk of cardiovascular diseases and possibly other diseases and should therefore be improved. Further studies are needed to determine the influence of estrogen on the effect on LC n-3 PUFA status.

Higher omega-3 index and DHA status in pregnant women compared to lactating women - Results from a German nation-wide cross-sectional study.

INTRODUCTION: During pregnancy and lactation, there is a high need of long-chain (LC) omega-3 fatty acids (n-3 PUFA), especially docosahexaenoic acid (DHA), for fetus and infant. Also, a low LC n-3 PUFA status during pregnancy is associated with postpartum depression. The aim of this cross-sectional study was to analyze the LC n-3 PUFA status in German women during pregnancy and lactation. MATERIAL AND METHODS: As a part of a nationwide cross-sectional study in which the nutrient status of women in different stages of life was determined, 213 pregnant (≥27th week of gestation) and 127 lactating women between 18 and 44 years were evaluated regarding their LC n-3 PUFA status by measuring the omega-3 index (relative eicosapentaenoic acid (EPA) and DHA concentration in erythrocyte fatty acid). RESULTS: The mean omega-3 index of the total study population was 6.23±1.48%. Pregnant women showed significant (p≤0.001) higher omega-3 index values (6.40±1.31%) and DHA concentrations (5.91±1.23%) than lactating women (omega-3 index: 5.50±1.34%; DHA: 4.79±1.27%). Woman with LC n-3 PUFA supplementation showed higher omega-3 index values (7.73±1.28%) vs. women without supplementation (6.04±1.39%, p≤0.001). Week of pregnancy, month of lactation as well as smoking were negatively associated with the omega-3 index. CONCLUSION: Comprehensive data on the long-term LC n-3 PUFA status of German women during pregnancy and lactation are presented. To evaluate an optimal maternal omega-3 index in view of the fetal and infant development further studies are needed.

Breastfeeding woman are at higher risk of vitamin D deficiency than non-breastfeeding women - insights from the German VitaMinFemin study.

BACKGROUND: Despite increased awareness of the adverse health effects of vitamin D deficiency, only a few studies have evaluated the vitamin D status (25-hydroxyvitamin D [25(OHD)]) of breastfeeding women and up to now, no information exits for German breastfeeding women. Therefore, the aim of study was to determine the vitamin D status of breastfeeding women compared to non-pregnant and non-breastfeeding (NPNB) women. METHODS: This cross-sectional study investigated 124 breastfeeding women and 124 age and season matched NPNB women from the German "Vitamin and mineral status among German women" study. The study participants were recruited from April 2013 to March 2015 and did not take vitamin D supplements. Serum 25(OH)D was analyzed by chemiluminescent immunoassay. RESULTS: Vitamin D deficiency (<25.0 nmol/L) was prevalent in 26.6% of the breastfeeding women. The majority of women (49.2%) showed 25(OH)D concentration between 25.0 and 49.9 nmol/L. In multiple binary logistic regression analysis, breastfeeding women had a 4.0-fold higher odds ratio (OR) (95% confidence interval [CI] 1.8, 8.7) for vitamin D deficiency than NPNB women. For breastfeeding women, the risk of vitamin D deficiency was higher in the winter and spring months (OR: 2.6, 95% CI 1.1, 6.3) and increased with lower longitude per one unit (OR 0.7, 95% CI 0.6, 0.9). CONCLUSION: Breastfeeding women in Germany had a higher risk of deficient vitamin D levels than NPNB women. In further studies, the optimal vitamin D status for breastfeeding women should be investigated and also the required vitamin D doses to ensure this vitamin D status. TRIAL REGISTRATION: German Clinical Trial Register (identification number: DRKS00004789).