Adverse metabolic risk profiles in Greenlandic Inuit children compared to Danish children

Ketogenic Effects of Multiple Doses of a Medium Chain Triglycerides Enriched Ketogenic Formula in Healthy Men under the Ketogenic Diet: A Randomized, Double-Blinded, Placebo-Controlled Study

Ketogenic diets, which are carbohydrate-restricted high-fat diets, may have therapeutic effects on various diseases, including cancer. However, ketogenic diets are often not standardized and, therefore, results are difficult to interpret. We previously investigated the usefulness of ketogenic diets in cancer therapy, where ketogenic formulas (KF) were used as supplements to enhance blood ketone bodies; however, the amount of KF was determined empirically with reference to blood ketone bodies levels. Here, to determine a standardized optimal amount of KF, we investigated temporal changes in blood ketone bodies (acetoacetic acid (AcAc), β-hydroxybutyrate (BHB)) and safety in 20 healthy individuals when KF was taken repeatedly under the conditions of a ketogenic diet (UMIN000034216). The diurnal variation in total ketone bodies, and AcAc and BHB levels significantly increased after lunch and after dinner, on the 4th day of KF administration. There were no significant safety issues related to KF in the context of anthropometric, metabolic, nutritional, urological and gastrointestinal parameters. In addition, ketogenic diets lead to changes in gut microbiota. KF showed a decrease in phylum Firmicutes. Our study provides baseline data of the usefulness of KF in a ketogenic diet.

Anthropometric measures and blood pressure of Greenlandic preschool children

The study aims to describe anthropometric data of Greenlandic preschool children, blood pressure (BP) measures and effects of maternal smoking during pregnancy in a follow-up of the ACCEPT birth cohort. The study included 102 children (55 boys and 47 girls) aged 3.5-5.5 years. Anthropometric measures included weight, height, head circumference (HC), body mass index (BMI), waist and hip circumference, ratio for height/weight, waist/height, waist/hip and BP measurements. Overweight and obesity-prevalence was determined using the international obesity task force BMI references for children. Significant increases in anthropometrics from 3.5 to 5.5 years included weight, height, HC and hip circumference, whereas ratio for height/weight, waist/hip and waist/height decreased. Boys had significantly larger HC than girls. The prevalence of overweight and obesity was similar (35.1%) between genders. Mean systolic and diastolic BP were 104 and 68 mmHg, respectively. Children of mothers smoking during pregnancy had higher hip circumference, lower waist/hip ratio and higher diastolic BP. The study present updated anthropometric data and BP of Greenlandic preschool children and effects of maternal smoking during pregnancy. The prevalence of overweight and obesity was higher than previously reported and maternal smoking during pregnancy affected the child data.Abbreviations ACCEPT: Adaptation to Climate Change, Environmental Pollution and dietary Transition; BMI: Body Mass Index; BP: Blood Pressure; Circ: Circumference; DBP: Diastolic Blood Pressure; FFH: Fisher-Freeman-Halton exact test; HC: Head Circumference; H: Height; HDL: high-density lipoprotein; HiC: Hip Circumference; IOTF International Obesity Task Force, Max: maximum, Min: minimum, P25: 25th percentile, P75: 75th percentile, SBP: Systolic Blood Pressure, SD: Standard Deviation; VDLD: very-low-density lipoprotein; WaC: Waist Circumference, W: Weight, WHO: World Health Organization.

Dietary habits, metabolic health and vitamin D status in Greenlandic children

OBJECTIVE

To compare the dietary habits of children living in northern villages and in the capital of Greenland, given the reported transition from traditional to westernised diet in adults over recent decades, and to explore the association between consumption of marine mammals and fish (MMF) and the children's metabolic profile and vitamin D status.

DESIGN

Children answered an FFQ encompassing sixty-four individual food types pooled into six food categories. Their pubertal stage, body fat, fitness level, metabolic profile (non-HDL-cholesterol, glycated Hb, insulin, glucose, high-sensitivity C-reactive protein) as well as serum 25-hydroxyvitamin D (25(OH)D) concentration were evaluated.

SETTING

Siorapaluk and Qaanaaq (north of Greenland) and Nuuk (west).

PARTICIPANTS

Children aged 6-18 years (n 177).

RESULTS

MMF were most frequently eaten by children from Siorapaluk (mean (sd): 73·4 (14·1) times/month), followed by children from Qaanaaq (37·0 (25·0) times/month), and least often eaten by children from Nuuk (23·7 (24·6) times/month; P < 0·001). Children from Qaanaaq consumed 'junk food' more frequently (P < 0·001) and fruits and vegetables less frequently (P < 0·01) than children from Nuuk. MMF consumption was positively associated with serum 25(OH)D concentration (P < 0·05), but the overall prevalence of vitamin D deficiency was high (18 %). No association was found between MMF consumption and metabolic parameters.

CONCLUSIONS

The dietary transition and influence of western diets have spread to the north of Greenland and only the most remote place consumed a traditional diet highly based on MMF. We found no strong associations of MMF consumption with metabolic health, but a positive association with vitamin D status.

A systematic review and meta-analysis of cardiorespiratory fitness among Indigenous populations in North America and circumpolar Inuit populations

Indigenous populations experience health disparities including increased obesity, diabetes and cardiovascular disease rates. Cardiorespiratory fitness is beneficial for maintaining positive health outcomes. The objective of this systematic review is to evaluate cardiorespiratory fitness among Indigenous populations including comparisons across genders, Indigenous identities, age groups, decades, socio-demographic variables and in comparison to non-Indigenous groups. Included articles reported various cardiorespiratory fitness measures using maximal treadmill or cycle ergometer tests, 20 m shuttle run, 1 mile run/walk test and 6 min walk test. From 14 databases searched in March 2017, including MEDLINE, EMBASE and Scopus, 1069 citations were evaluated and 39 articles included, representing 32 investigations and 10,579 individuals. First Nations/American Indian (FN/AI) adults have greater cardiorespiratory fitness than Inuit. Inuit and FN/AI men and boys have higher cardiorespiratory fitness than women and girls. Lower cardiorespiratory fitness is associated with obesity, metabolic syndrome and a western lifestyle. Cardiorespiratory fitness has declined among Inuit adults, averaging 51.7 ± 7.9 mL·kg^-1·min^-1 in 1970 to 37.7 ± 6.9 mL·kg^-1·min^-1 in 2000. Among men, FN/AI have greater cardiorespiratory fitness compared to European-descents, and European-descents have greater cardiorespiratory fitness compared to Inuit. The 1 mile run/walk time showed that FN/AI boys, girls, and youth had faster times compared to European-descendants, but 20 m shuttle run showed that European-descent boys and youth advanced to further stages compared to FN/AI populations. Cardiorespiratory fitness is declining, and among some Indigenous populations to lower levels than European-descent populations. Improving cardiorespiratory fitness for Indigenous populations should be considered a primary health strategy.

Increased asthma and adipose tissue inflammatory gene expression with obesity and Inuit migration to a western country

BACKGROUND

An overlap between obesity and asthma exists, and inflammatory cells in adipose tissue could drive the development of asthma. Comparison of adipose tissue gene expression among Inuit living in Greenland to those in Denmark provides an opportunity to assess how changes in adipose tissue inflammation can be modified by migration and diet.

OBJECTIVE

To examine mast cell and inflammatory markers in adipose tissue and the association with asthma.

METHODS

Two Inuit populations were recruited, one living in Greenland and another in Denmark. All underwent adipose subcutaneous biopsy, followed by clinical assessment of asthma, and measurement of AHR. Adipose tissue biopsies were homogenised, RNA extracted, and PCR was performed to determine the relative gene expression of mast cell (tryptase, chymase, CPA3) and inflammatory markers (IL-6, IL-1β, and CD163).

RESULTS

Of the 1059 Greenlandic Inuit participants, 556 were living in Greenland and 6.4% had asthma. Asthma was increased in Denmark (9%) compared to Greenland (3.6%, p < 0.0001) and associated with increased adipose tissue IL-6 gene expression and increased BMI. There was no association between asthma and adipose tissue mast cell gene expression. Pro-inflammatory gene expression (IL-6, IL-1β) was higher in those living in Denmark, and with increasing BMI and dietary changes. The anti-inflammatory (M2) macrophage marker, CD163, was higher in Greenland-dwelling Inuit (p < 0.01).

CONCLUSIONS

No association was found between gene expression of mast cell markers in adipose tissue and asthma. Among Greenlandic Inuit, adipose tissue inflammation is also increased in those who migrate to Denmark, possibly as a result of dietary changes.

BMI percentile-for-age overestimates adiposity in early compared with late maturing pubertal children

OBJECTIVE

Early pubertal timing is consistently associated with increased BMI percentile-for-age in pubertal girls, while data in boys are more ambiguous. However, higher BMI percentile-for-age may be a result of the earlier puberty per se rather than vice versa. The aim was to evaluate markers of adiposity in relation to pubertal timing and reproductive hormone levels in healthy pubertal boys and girls.

STUDY DESIGN

Population-based cross-sectional study (The Copenhagen Puberty Study). Eight-hundred and two healthy Caucasian children and adolescents (486 girls) aged 8.5-16.5 years participated. BMI and bioelectric impedance analyses (BIA) were used to estimate adiposity. Clinical pubertal markers (Tanner stages and testicular volume) were evaluated. LH, FSH, estradiol, testosterone, SHBG and IGF1 levels were determined by immunoassays.

RESULTS

In all age groups, higher BMI (all 1 year age-groups, P ≤ 0.041) was found with early compared with late maturation, despite similar BIA-estimated body fat percentage (BIA-BF%). Neither BMI nor BIA-BF% differed for a given stage of maturation. BMI percentile-for-age and prevalence of overweight/obesity were higher in the early compared with late matured pubertal children (all P ≤ 0.038), despite similar BIA-BF%. Pubertal girls with BIA-BF >29% had significantly lower LH and FSH levels compared with normal-weight girls (P ≤ 0.041).

CONCLUSIONS

Early maturational timing was not associated with higher adiposity for a given stage of puberty. Using BMI percentile-for-age overestimated the degree of adiposity in early pubertal compared with late pubertal children.

Elevated serum IGF-I, but unaltered sex steroid levels, in healthy boys with pubertal gynaecomastia

OBJECTIVE

Pubertal gynaecomastia is a very common condition. Although the underlying aetiology is poorly understood, it is generally accepted that excess of oestrogens and deficit of androgens are involved in the pathogenesis. Furthermore, adiposity as well as the GH/IGF-I axis may play a role. In this study, we elucidate the association of adiposity and levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), testosterone, oestrogen, IGF-I and IGFBP-3 with the presence of pubertal gynaecomastia in a large cohort of healthy boys.

PATIENTS

A total of 501 healthy Danish school boys (aged 6·1-19·8 year) from the COPENHAGEN Puberty Study.

MEASUREMENTS

Anthropometry and pubertal stages (PH1-6 and G1-5) were evaluated, and the presence of gynaecomastia was assessed. Body fat percentage was calculated by means of four skin folds and impedance. Nonfasting blood samples were analysed for FSH, LH, testosterone, SHBG, oestradiol, IGF-I, IGFBP-3 and prolactin.

RESULTS

We found that 23% (31/133) of all pubertal boys had gynaecomastia. More specifically, 63% (10/16) of boys in genital stage 4 had gynaecomastia. Boys with gynaecomastia had significantly higher IGF-I levels compared with controls (IGF-I SD-score 0·72 vs -0·037, P < 0·001). This difference was maintained after adjusting for confounders (age and pubertal stage). Sex steroid levels, oestradiol/testosterone ratio or free testosterone were not associated with the presence of gynaecomastia with or without adjustment for confounders.

CONCLUSIONS

IGF-I levels were elevated in healthy boys with pubertal gynaecomastia compared with boys without gynaecomastia, whereas sex steroid levels did not differ. We speculate that the GH-IGF-I axis may be involved in the pathogenesis of pubertal gynaecomastia.

Ethnic differences in leptin and adiponectin levels between Greenlandic Inuit and Danish children

Objective

In a recent study, we found that Greenlandic Inuit children had a more adverse metabolic profile than Danish children. Aerobic fitness and adiposity could only partly account for the differences. Therefore, we set out to evaluate and compare plasma leptin and adiponectin levels in Danish and Inuit children.

Methods

In total, 187 Inuit and 132 Danish children (5.7–17.1 years) had examinations of anthropometrics, body fat content, pubertal staging, fasting blood and aerobic fitness.

Results

Plasma leptin was higher in Danish boys [3,774 (4,741–3,005)] [pg/mL unadjusted geometric mean (95% CI)] compared to both northern [2,076 (2,525–1,706)] (p<0.001) and southern (2,515 (3,137–2,016)) (p<0.001) living Inuit boys and higher in Danish girls [6,988 (8,353–5,847)] compared to southern living Inuit girls [4,910 (6,370–3,785)] (p=0.021) and tended to be higher compared to northern living Inuit girls [5,131 (6,444–4,085)] (p=0.052). Plasma adiponectin was higher for both Danish boys [22,359 (2,573–19,428)] [ng/mL unadjusted geometric mean (95% CI)] and girls [26,609 (28,994–24,420)] compared to southern living Inuit boys [15,306 (18,406–12,728)] and girls [18,864 (22,640–15,717)] (both p<0.001), respectively. All differences remained after adjustment for body fat percentage (BF%), aerobic fitness, age and puberty. The leptin/adiponectin ratio was higher in Danish boys and tended to be higher in Danish girls compared to northern living Inuit boys and girls, respectively. These differences were eliminated after adjustment for BF%, aerobic fitness, age and puberty.

Conclusions

In contrast to our hypothesis, plasma leptin was higher in Danish children despite a more healthy metabolic profile compared to Inuit children. As expected, plasma adiponectin was lowest in Inuit children with the most adverse metabolic profile.