The British journal of nutrition
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Randomized Controlled Trial
Glucose uptake by the brain on chronic high-protein weight-loss diets with either moderate or low amounts of carbohydrate.
Previous work has shown that hunger and food intake are lower in individuals on high-protein (HP) diets when combined with low carbohydrate (LC) intakes rather than with moderate carbohydrate (MC) intakes and where a more ketogenic state occurs. The aim of the present study was to investigate whether the difference between HPLC and HPMC diets was associated with changes in glucose and ketone body metabolism, particularly within key areas of the brain involved in appetite control. A total of twelve men, mean BMI 34·9 kg/m², took part in a randomised cross-over trial, with two 4-week periods when isoenergetic fixed-intake diets (8·3 MJ/d) were given, with 30% of the energy being given as protein and either (1) a very LC (22 g/d; HPLC) or (2) a MC (182 g/d; HPMC) intake. ⋯ The 9-fold difference in carbohydrate intakes between the HPLC and HPMC dietary interventions led to a 5% lower supply of glucose to the brain. Despite this, the uptake of glucose by the fifty-four regions of the brain analysed remained similar for the two dietary interventions. In conclusion, differences in the composite hunger score observed for the two dietary interventions are not associated with the use of alternative fuels by the brain.
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Randomized Controlled Trial
Children and youth do not compensate for an imposed bout of prolonged sitting by reducing subsequent food intake or increasing physical activity levels: a randomised cross-over study.
The behavioural impact of an imposed bout of prolonged sitting is yet to be investigated in the paediatric population. The objective of the present study was to determine the acute effect of prolonged sitting on ad libitum food intake and spontaneous physical activity (PA) levels in healthy children and youth. ⋯ Despite significant differences in sedentary behaviour and activity levels during the three in-laboratory sessions (all P< 0·01), we did not observe any differences in ad libitum food intake immediately following exposure to each experimental condition or any changes in the levels of sedentary behaviour or PA in the 24 h following exposure to each experimental condition (all P>0·25). These findings suggest that children and youth may not compensate for an imposed bout of sedentary behaviour by reducing subsequent food intake or increasing PA levels.
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Randomized Controlled Trial
Combining functional features of whole-grain barley and legumes for dietary reduction of cardiometabolic risk: a randomised cross-over intervention in mature women.
The usefulness of dietary strategies against cardiometabolic risk is increasingly being acknowledged. Legumes and whole grains can modulate risk markers associated with cardiometabolic diseases, but their possible additive/synergistic actions are unknown. The objective of the present study was to assess, in healthy subjects, the effect of a diet including specific whole-grain barley products and legumes with prior favourable outcomes on cardiometabolic risk parameters in semi-acute studies. ⋯ D1 also reduced apoB (P< 0·001) and γ-glutamyl transferase (P< 0·05) levels, diastolic blood pressure (P< 0·05) and the Framingham cardiovascular risk estimate (P< 0·05). D1 increased colonic fermentative activity, as judged from the higher (P< 0·001) breath hydrogen levels recorded. In conclusion, a specific barley/legume diet improves cardiometabolic risk-associated biomarkers in a healthy cohort, showing potential preventive value beyond that of a nutritionally well-designed regimen.
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Randomized Controlled Trial
Co-administration of methyl donors along with guanidinoacetic acid reduces the incidence of hyperhomocysteinaemia compared with guanidinoacetic acid administration alone.
Guanidinoacetic acid (GAA) is the natural biosynthetic precursor of creatine, in a metabolic reaction that requires only a methyl group transfer. The use of GAA as a food additive for restoring creatine load in human tissues is rather unexplored and data on efficacy and safety are limited. In particular, an increase in serum homocysteine after GAA administration can be regarded as critical and should be prevented. ⋯ Hyperhomocysteinaemia was found in 55.6 % of participants supplemented with GAA, while no participant experienced hyperhomocysteinaemia in the group supplemented with GAA and methyl donors (P= 0.01). In summary, both interventions strongly influenced creatine metabolism, resulting in a significant increase in fasting serum creatine. The concomitant supplementation of methyl donors along with GAA largely precluded the elevation of serum homocysteine caused by GAA administration alone.
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Randomized Controlled Trial
Effects of milk and milk constituents on postprandial lipid and glucose metabolism in overweight and obese men.
Studies have suggested that two major milk constituents, casein and Ca, favourably affect postprandial responses. However, effects of milk on postprandial metabolism are unknown. We therefore investigated effects of using milk with a fat-containing meal on lipid and glucose responses in overweight men. ⋯ The present results indicate that the intake of milk with a fat-containing meal enhances postprandial TAG and insulin responses and may blunt glucose increases. The protein fraction of milk seems to be the main determinant for the effects on TAG and glucose. Ca did not change any of the postprandial responses.