Antioxidant Rich Potato Improves Arterial Stiffness in Healthy Adults.

Arterial stiffness is an emerging risk factor for cardiovascular disease and dietary anthocyanins may be important in mediating vascular tone. The present study investigated the effect of consumption of an anthocyanin-rich potato, Purple Majesty on arterial stiffness measured as pulse wave velocity in 14 healthy male and female adults. Participants consumed 200 g/day of cooked purple potato containing 288 mg anthocyanins, or a white potato containing negligible anthocyanins for 14 days, separated by a 7-day washout period. Non-invasive assessment of vascular tone by pulse wave velocity was determined in addition to systolic and diastolic blood pressure, high-density lipoproteins, low-density lipoproteins, triglycerides, glucose, insulin and C-reactive protein. Pulse wave velocity was significantly reduced (p = 0.001) following Purple Majesty consumption for 14-days. There were no significant changes with any other clinical parameter measured, and no changes following white potato consumption. The findings from this short-term study indicate a potential effect of Purple Majesty consumption on arterial stiffness.

Chrono-nutrition: a review of current evidence from observational studies on global trends in time-of-day of energy intake and its association with obesity.

The importance of the circadian rhythm in regulating human food intake behaviour and metabolism has long been recognised. However, little is known as to how energy intake is distributed over the day in existing populations, and its potential association with obesity. The present review describes global trends in time-of-day of energy intake in the general population based on data from cross-sectional surveys and longitudinal cohorts. Evidence of the association between time-of-day of energy intake and obesity is also summarised. Overall, there were a limited number of cross-sectional surveys and longitudinal cohorts that provided data on time-of-day of energy intake. In the identified studies, a wide variation in time-of-day of energy intake was observed, with patterns of energy distribution varying greatly by country and geographical area. In relation to obesity, eight cross-sectional surveys and two longitudinal cohorts were identified. The association between time-of-day of energy intake and obesity varied widely, with several studies reporting a positive link between evening energy intake and obesity. In conclusion, the current review summarises global trends in time-of-day of energy intake. The large variations across countries and global regions could have important implications to health, emphasising the need to understand the socio-environmental factors guiding such differences in eating patterns. Evidence of the association between time-of-day of energy intake and BMI also varied. Further larger scale collaborations between various countries and regions are needed to sum data from existing surveys and cohorts, and guide our understanding of the role of chrono-nutrition in health.

Association between an anti-inflammatory and anti-oxidant dietary pattern and diabetes in British adults: results from the national diet and nutrition survey rolling programme years 1-4.

This study investigated the cross-sectional association between an anti-inflammatory and anti-oxidant dietary pattern and diabetes in the national diet and nutrition survey (NDNS) rolling programme years 1-4. A total of 1531 survey members provided dietary data. Reduced Rank Regression (RRR) was used to derive an anti-inflammatory and anti-oxidant dietary pattern. Serum C-reactive protein (CRP) and plasma carotenoids were selected as response variables and markers of inflammation and antioxidant status, respectively. Overall, 52 survey members had diabetes. The derived anti-inflammatory and anti-oxidant dietary pattern was inversely related to CRP and positively to carotenoids. It was associated with lower odds of diabetes (multivariate adjusted OR for highest compared with lowest quintile: 0.17; 95%CI: 0.04-0.73; p for linear trend = 0.013). In conclusion, an anti-inflammatory and anti-oxidant dietary pattern is inversely related to diabetes. Further research is required to understand the overall framework within which foods and nutrients interact to affect metabolic pathways related to diabetes risk.

Trends in food consumption over 30 years: evidence from a British birth cohort.

BACKGROUND/OBJECTIVES: As populations are ageing, more emphasis is placed on healthy ageing. Over the past decades, food consumption patterns and food availability have also changed drastically, and therefore this study aimed to describe these changes in an ageing population. SUBJECTS/METHODS: Food consumption of participants from the Medical Research Council National Survey on Health and Development, a British birth cohort study, was assessed using a 5-day estimated food records at 60-64 years (2006-11), 53 years (1999), 43 years (1989) and 36 years (1982). Only those who recorded ⩾3 days at all four time points were included in the analyses, n=989 (n=438 men and n=551 women); trends were tested using the Friedman test. RESULTS: Consumption of white bread, whole milk, fats and oils, meat and meat products, alcoholic drinks, coffee, sugar, preserves and confectionery decreased (P<0.001), whereas consumption of wholemeal and granary bread, semi-skimmed milk, fish and fruit and vegetables increased (P<0.001) over time. These observed changes in food consumption reflect a healthier diet, for example, replacement of white bread by granary and wholemeal bread, lower consumption of red and processed meats, somewhat higher consumption of fish, higher consumption of vegetables and lower consumption of coffee. This could partly be because of ageing of the cohort or compliance with dietary recommendations, facilitated by greater availability of healthier foods, such as semi-skimmed milk and wholegrain bread, in the UK. CONCLUSIONS: The changes in food consumption in this British birth cohort over the past three decades are encouraging and reflect a healthier diet in the later years.

Biomarkers of diabetes risk in the National Diet and Nutrition Survey rolling programme (2008-2011).

This study describes the distribution of glycosylated haemoglobin (Hb(A1c)) and glucose concentrations in the combined year 1 (2008-2009), year 2 (2009-2010) and year 3 (2010-2011) of the National Diet and Nutrition Survey (NDNS) rolling programme. The NDNS rolling programme is a nationally representative survey of food consumption, nutrient intakes and nutritional status of people aged 1.5 years and over living in England, Wales, Scotland and Northern Ireland. The study population comprised survey members who completed three or four days of dietary recording and who provided a blood sample. After excluding survey members with self-reported diabetes (n=25), there were 1016 results for HbA1c and 942 for glucose (not the same individuals in each case). Around 5.4% of men and 1.7% of women aged 19-64 years, and 5.1% of men and 5.9% of women aged ≥65 years had impaired fasting glucose (glucose concentrations 6.1-6.9 mmol/L). Over 20% of men aged ≥65 years had fasting glucose concentrations above the clinical cut-off for diabetes (≥7 mmol/L) compared to 2.1% of women of similar age (p=0.007). Similarly, 16.4% of men had Hb(A1c) concentrations ≥6.5%, compared to 1.5% of women (p=0.003). Children and teenagers had fasting glucose and Hb(A1c) values largely within the normal range. To conclude, this is the first study to provide data on the distribution of HbA1c and glucose concentrations in a nationally representative sample of the British population. The high prevalence of men aged ≥65 years with Hb(A1c) and glucose concentrations above the clinical cut-off of diabetes warrants further attention.

Diurnal eating rhythms: association with long-term development of diabetes in the 1946 British birth cohort.

BACKGROUND AND AIMS: Few studies have described the association between time-of-day of macronutrient intake and diabetes. This study examined the prospective association between time-of-day and nutrient composition of eating occasions in relation to diabetes incidence in the 1946 British birth cohort. METHODS AND RESULTS: The study included 1618 survey members who completed dietary assessment at age 43 (1989) and for whom data on glycosylated haemoglobin at age 53 years (1999) were available. Diet was assessed using 5d estimated diaries, divided into seven meal slots: breakfast, mid-morning, lunch, mid-afternoon, dinner, late evening and extras. Diabetes was defined by glycosylated haemoglobin (HbA1c) ≥ 6.5% or diabetes medication use. The association between time-of-day of macronutrient intake at age 43 years and diabetes at age 53 years was assessed using logistic multivariate nutrient density models after adjustment for potential confounders. There were 66 cases of diabetes at age 53 years. Survey members with diabetes obtained 50.4% of their energy from carbohydrate at breakfast compared to 55.9% in survey members without diabetes (P = 0.001). Increasing carbohydrate intake at breakfast at the expense of fat was related to lower odds ratio (OR) of diabetes (OR = 0.86; 95%CI = 0.79-0.93; P < 0.001). This relationship was attenuated after adjustment for body mass index and waist circumference. CONCLUSION: Increasing energy intake from carbohydrate at the expense of fat at breakfast is inversely associated with 10-year diabetes incidence. However, further studies are required to elucidate whether the type or source of carbohydrates or fat influences the above association.

Time-of-day and nutrient composition of eating occasions: prospective association with the metabolic syndrome in the 1946 British birth cohort.

BACKGROUND: Diet is a key modifiable factor in the prevention and treatment of the metabolic syndrome. However, few studies have examined the prospective association between time-of-day of nutrient intake and the metabolic syndrome. OBJECTIVE: To examine the association between time-of-day and nutrient composition of eating occasions and the long-term development of metabolic syndrome in the Medical Research Council (MRC) National Survey of Health and Development (NSHD; 1946 British birth cohort). METHODS: The analysis comprised 1488 survey members who completed at least 3 days of estimated diet records at age 43 years (1989) and for whom data on metabolic syndrome at age 53 years (1999) were available. Dietary records were divided into seven meal slots: breakfast, mid-morning, lunch, mid-afternoon, dinner, late evening and extras. Metabolic syndrome was defined by the criteria of the adult treatment panel (ATPIII8), and was modified to include glycosylated haemoglobin instead of fasting glucose. Associations between time-of-day of nutrient intake at age 43 years and prevalence of metabolic syndrome at age 53 years were assessed using multivariate nutrient density logistic models after adjustment for sex, social class, smoking status, region, alcohol intake and recreational physical activity. RESULTS: There were 390 cases of metabolic syndrome at age 53 years. Substituting 5% of energy from carbohydrate for a similar amount of energy from fat at breakfast (odds ratio=0.93; 95% confidence interval=0.89-0.98; P=0.002) and mid-morning at age 43 years (odds ratio=0.96; 95% confidence interval=0.93-0.99; P=0.011) was associated with lower odds of the metabolic syndrome at age 53 years. Carbohydrate intake at breakfast or mid-morning was particularly protective against abdominal obesity (P0.001). Increasing carbohydrate intake at breakfast while simultaneously decreasing fat intake was also negatively related to triacylglycerols (P0.001). CONCLUSIONS: Increasing carbohydrate intake in the morning while simultaneously reducing fat intake could be protective against long-term development of the metabolic syndrome and its components.

Differential effect of polyphenol-rich dark chocolate on biomarkers of glucose metabolism and cardiovascular risk factors in healthy, overweight and obese subjects: a randomized clinical trial.

The association between excess cortisol and various parameters of metabolic syndrome including hypertension, insulin resistance and dyslipidaemia is increasingly recognised. The present single-blind randomised placebo-controlled cross-over study compared the effect of polyphenol-rich dark chocolate (DC) on biomarkers of glucose metabolism, lipid profile, and blood pressure (BP) in females with BMI ≥ 25 kg m(-2) (n = 21) and females with BMI < 25 kg m(-2) (n = 21). Volunteers consumed 20 g of DC containing 500 mg polyphenols or a placebo DC with negligible polyphenol-content daily for 4 weeks, separated by a 2-week washout period. Systolic BP and diastolic BP decreased after 4 weeks of polyphenol-rich DC. Placebo raised fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and salivary cortisol, an effect that was significantly different from polyphenol-rich DC which had a negligible effect on fasting insulin, HOMA-IR and salivary cortisol. Females with BMI ≥ 25 kg m(-2) responded less favourably to placebo than lean females and consequently had higher fasting insulin and HOMA-IR, in addition to a lower quantitative sensitivity check index (QUICKI) after ingestion of placebo compared to polyphenol-rich DC. No significant changes in lipid profile were observed. This study provides evidence for the metabolic benefits of consuming polyphenol-rich dark chocolate while demonstrating the possibility of adverse effects occurring with polyphenol-poor chocolate placebo.

Daily profiles of energy and nutrient intakes: are eating profiles changing over time?

BACKGROUND/OBJECTIVES: Associations between timing of eating occasions and their nutrient composition and health have been described in interventional and cross-sectional studies. However, data from longitudinal data are limited. This study examined 17-year changes in energy and macronutrient intake across eating occasions in the 1946 British birth cohort. SUBJECTS/METHODS: Data were obtained from the 1946 British birth cohort. Cohort members completed 5d-estimated diaries at ages 36 (1982), 43 (1989) and 53 years (1999). Data from subjects who provided dietary data at all three time points were analysed (n = 1253). Repeated-measures analysis of variance with post hoc Bonferroni's adjustment was used to examine changes in energy and macronutrient at breakfast, mid-morning, lunch, mid-afternoon, evening and extra meal slots between 1982 and 1999. Analyses were stratified by sex and social class. RESULTS: The proportion of energy and macronutrients consumed at lunch declined between 1982 and 1999, which was compensated by a greater intake in the mid-afternoon and evening. This trend was seen across sex and social class, although women and adults with a non-manual occupation reported greater energy, carbohydrate and non-starch polysaccharide intake at breakfast in 1982 and had a higher protein intake in the evening compared with men and adults with a manual occupation. CONCLUSIONS: The timing of energy and nutrient intake has shifted slightly over time, with a greater proportion of intake later in the day. The association between the observed sex and occupational social class differences in eating profiles and chronic disease warrants investigation.

Intake of polyphenol-rich pomegranate pure juice influences urinary glucocorticoids, blood pressure and homeostasis model assessment of insulin resistance in human volunteers.

Pomegranate juice (PJ; also known as pomegreat pure juice) provides a rich and varied source of polyphenolic compounds that may offer cardioprotective, anti-atherogenic and antihypertensive effects. The aim of this study was to investigate the effect of PJ consumption on glucocorticoids levels, blood pressure (BP) and insulin resistance in volunteers at high CVD risk. Subjects (twelve males and sixteen females) participated in a randomised, placebo-controlled cross-over study (BMI: 26·77 (sd 3·36) kg/m(2); mean age: 50·4 (sd 6·1) years). Volunteers were assessed at baseline, and at weeks 2 and 4 for anthropometry, BP and pulse wave velocity. Cortisol and cortisone levels in urine and saliva were determined by specific ELISA methods, and the cortisol/cortisone ratio was calculated. Fasting blood samples were obtained to assess plasma lipids, glucose, insulin and insulin resistance (homeostasis model assessment of insulin resistance). Volunteers consumed 500 ml of PJ or 500 ml of a placebo drink containing a similar amount of energy. Cortisol urinary output was reduced but not significant. However, cortisol/cortisone ratios in urine (P = 0·009) and saliva (P = 0·024) were significantly decreased. Systolic BP decreased from 136·4 (sd 6·3) to 128·9 (sd 5·1) mmHg (P = 0·034), and diastolic BP from 80·3 (sd 4·29) to 75·5 (sd 5·17) mmHg (P = 0·031) after 4 weeks of fruit juice consumption. Pulse wave velocity decreased from 7·5 (sd 0·86) to 7·44 (sd 0·94) m/s (P = 0·035). There was also a significant reduction in fasting plasma insulin from 9·36 (sd 5·8) to 7·53 (sd 4·12) mIU/l (P = 0·025) and of homeostasis model assessment of insulin resistance (from 2·216 (sd 1·43) to 1·82 (sd 1·12), P = 0·028). No significant changes were seen in the placebo arm of the study. These results suggest that PJ consumption can alleviate key cardiovascular risk factors in overweight and obese subjects that might be due to a reduction in both systolic and diastolic BP, possibly through the inhibition of 11ß-hydroxysteroid dehydrogenase type 1 enzyme activity as evidenced by the reduction in the cortisol/cortisone ratio. The reduction in insulin resistance might have therapeutic benefits for patients with non-insulin-dependent diabetes, obesity and the metabolic syndrome.