Dose-Dependent Associations of Dietary Glycemic Index, Glycemic Load, and Fiber With 3-Year Weight Loss Maintenance and Glycemic Status in a High-Risk Population: A Secondary Analysis of the Diabetes Prevention Study PREVIEW

<a>OBJECTIVE</a> <p>To <a></a><a>examine longitudinal and dose-dependent associations of dietary glycemic index (GI), glycemic load (GL), and fiber with body weight and glycemic status during 3-year weight-loss maintenance (WLM)</a> in high-risk adults.</p> <p>RESEARCH DESIGN AND METHODS</p> <p>This secondary analysis used pooled data from the PREVIEW randomized controlled trial, which was designed to test the effects of four diet and physical activity interventions. 1,279 participants with overweight or obesity (aged 25–70 years; BMI≥25 kg·m^-2) and pre-diabetes at baseline were included. <a>Multi-adjusted linear mixed models </a><a>with repeated measurements</a> were used to assess longitudinal and dose-dependent associations, by merging the participants into one group and dividing them into <a></a><a>GI, GL, and fiber </a>tertiles, respectively. </p> <p>RESULTS</p> <p>In the available-case and complete-case analyses, each 10-unitincrement in GI was associated with a greater regain of weight (0.46 kg·year^-1; 95% CI 0.23, 0.68; <i>P</i><0.001) and increase in HbA_1c. Each 20-unit increment in GL was associated with a greater regain of weight (0.49 kg·year^-1; 0.24, 0.75; <i>P</i><0.001) and increase in HbA_1c. The associations of GI and GL with HbA_1c were independent of weight change. Compared with those in the lowest tertiles, participants in the highest GI and GL tertiles had significantly higher weight regain and increases in HbA_1c. Fiber was inversely associated with increases in waist circumference, but the associations with weight regain and glycemic status did not remain robust in different analyses.</p> <p>CONCLUSIONS</p> <p>Dietary GI and GL were positively associated with weight regain and deteriorating glycemic status. Stronger evidence on the role of fiber is needed.</p>

Dose-Dependent Associations of Dietary Glycemic Index, Glycemic Load, and Fiber With 3-Year Weight Loss Maintenance and Glycemic Status in a High-Risk Population: A Secondary Analysis of the Diabetes Prevention Study PREVIEW

<a>OBJECTIVE</a> <p>To <a></a><a>examine longitudinal and dose-dependent associations of dietary glycemic index (GI), glycemic load (GL), and fiber with body weight and glycemic status during 3-year weight-loss maintenance (WLM)</a> in high-risk adults.</p> <p>RESEARCH DESIGN AND METHODS</p> <p>This secondary analysis used pooled data from the PREVIEW randomized controlled trial, which was designed to test the effects of four diet and physical activity interventions. 1,279 participants with overweight or obesity (aged 25–70 years; BMI≥25 kg·m^-2) and pre-diabetes at baseline were included. <a>Multi-adjusted linear mixed models </a><a>with repeated measurements</a> were used to assess longitudinal and dose-dependent associations, by merging the participants into one group and dividing them into <a></a><a>GI, GL, and fiber </a>tertiles, respectively. </p> <p>RESULTS</p> <p>In the available-case and complete-case analyses, each 10-unitincrement in GI was associated with a greater regain of weight (0.46 kg·year^-1; 95% CI 0.23, 0.68; <i>P</i><0.001) and increase in HbA_1c. Each 20-unit increment in GL was associated with a greater regain of weight (0.49 kg·year^-1; 0.24, 0.75; <i>P</i><0.001) and increase in HbA_1c. The associations of GI and GL with HbA_1c were independent of weight change. Compared with those in the lowest tertiles, participants in the highest GI and GL tertiles had significantly higher weight regain and increases in HbA_1c. Fiber was inversely associated with increases in waist circumference, but the associations with weight regain and glycemic status did not remain robust in different analyses.</p> <p>CONCLUSIONS</p> <p>Dietary GI and GL were positively associated with weight regain and deteriorating glycemic status. Stronger evidence on the role of fiber is needed.</p>

Dose-Dependent Associations of Dietary Glycemic Index, Glycemic Load, and Fiber With 3-Year Weight Loss Maintenance and Glycemic Status in a High-Risk Population: A Secondary Analysis of the Diabetes Prevention Study PREVIEW

<a>OBJECTIVE</a> <p>To <a></a><a>examine longitudinal and dose-dependent associations of dietary glycemic index (GI), glycemic load (GL), and fiber with body weight and glycemic status during 3-year weight-loss maintenance (WLM)</a> in high-risk adults.</p> <p>RESEARCH DESIGN AND METHODS</p> <p>This secondary analysis used pooled data from the PREVIEW randomized controlled trial, which was designed to test the effects of four diet and physical activity interventions. 1,279 participants with overweight or obesity (aged 25–70 years; BMI≥25 kg·m^-2) and pre-diabetes at baseline were included. <a>Multi-adjusted linear mixed models </a><a>with repeated measurements</a> were used to assess longitudinal and dose-dependent associations, by merging the participants into one group and dividing them into <a></a><a>GI, GL, and fiber </a>tertiles, respectively. </p> <p>RESULTS</p> <p>In the available-case and complete-case analyses, each 10-unitincrement in GI was associated with a greater regain of weight (0.46 kg·year^-1; 95% CI 0.23, 0.68; <i>P</i><0.001) and increase in HbA_1c. Each 20-unit increment in GL was associated with a greater regain of weight (0.49 kg·year^-1; 0.24, 0.75; <i>P</i><0.001) and increase in HbA_1c. The associations of GI and GL with HbA_1c were independent of weight change. Compared with those in the lowest tertiles, participants in the highest GI and GL tertiles had significantly higher weight regain and increases in HbA_1c. Fiber was inversely associated with increases in waist circumference, but the associations with weight regain and glycemic status did not remain robust in different analyses.</p> <p>CONCLUSIONS</p> <p>Dietary GI and GL were positively associated with weight regain and deteriorating glycemic status. Stronger evidence on the role of fiber is needed.</p>

Weight regain after slimming induced by an energy-restricted diet depends on interleukin-6 and peroxisome-proliferator-activated-receptor-γ2 gene polymorphisms

Weight-loss maintenance after following an energy-restricted diet is a major problem that a number of studies are trying to characterise. The aim of the present study was to investigate the role of IL-6 -174G > C and PPAR-γ2 Pro12Ala variants on weight regulation in obese subjects receiving a low-energy diet and at 1 year after the acute slimming period. Sixty-seven volunteers (age 34·7 (sd 7·0) years; BMI 35·8 (sd 4·8) kg/m2) were enrolled in a 10-week dietary intervention and were contacted again 1 year after the end of this period. Body composition was measured at three times during the study. Also, PPAR-γ2 Pro12Ala and IL-6 -174G > C polymorphisms were analysed in the participants. No statistical differences were observed depending on the genetic variants at baseline for anthropometric variables, or after the intervention. However, the C allele of the -174G > C IL-6 gene polymorphism was more frequently observed (P=0·032) in subjects with successful weight maintenance (<10 % weight regain). In fact, the C allele partially protected against weight regain (odds ratio 0·24;P=0·049), while the conjoint presence of both gene variants (C+ and Ala+) further improved the ability for weight maintenance (odds ratio 0·19;P=0·043). The present study demonstrates that the C allele of the -174G > C polymorphism gives protection against regain of weight lost. Moreover, the presence of the Ala allele of the PPARγ-2 together with the C allele strengthens this protection. These findings support a role for these polymorphisms on weight regulation and suggest a synergetic effect of both variants on weight maintenance after following a diet to lose weight.

Effect of anorexia nervosa on gonadotrophin secretion in a patient with gonadal dysgenesis

The 11th documented concurrence of anorexia nervosa (AN) and XO-gonadal dysgenesis (GD) is reported. This is the first endocrine study of such a disease combination. The patient, a 15-year-old girl, has been followed since early childhood and comprehensive endocrinological investigations were performed before, during and after the episode of AN. The dynamic changes in the thyroid and pituitary hormones were in concordance with those already observed by us as well as by others in patients with AN. The most remarkable observation concerned the gonadotrophin secretion: during the anorectic episode basal levels and peak responses to LRH of both LH and FSH were seen to decrease from the hypergonadotrophic range to the normal prepubertal range whereas after recovery from AN and regain of weight these rose back to castration levels. AN would seem to be the only condition yet known able to abolish temporarily the hypergonadotrophic state of GD, a fact favouring the hypothesis that AN is associated with a reversible hypothalamic dysfunction. It is assumed that this disturbance is due to nutritional as well as to psychological factors. The significance of the coexistence of AN and GD is discussed and it is suggested that psychological factors in GD may be implicated in this association.

Maintenance rations for Merino sheep. 1. A comparative study of daily and weekly feeding on rations containing high proportions of wheat and several proportions of roughage to concentrate

Groups of full-mouthed Merino wethers were given 4.25 lb. starch equivalent (4,550 calories of net energy) per sheep per week, to maintain a low to moderate store condition of 75 lb. body weight, on each of four rations, namely 50:50, 30:60, 20:80, and 10:90 mixtures of wheaten chaff and wheat. Finely-ground limestone was added to these rations to correct calcium phosphorus imbalance. The groups were paired, one of each pair being given the food once a week and the other being given it in daily portions. The weekly-fed groups were brought on to this regime during a preparatory period of 77 days during which they were fed at intervals which were gradually increased from 3 to 7 days. The surviving sheep in the daily-fed groups maintained their mean body weight and general condition as well as did those in the weekly-fed groups but at the end of the experiment the range in body weight in the daily-fed groups was greater: 41.9 per cent. of the daily-fed animals gained in weight during the period of 344 days, whereas only 14.2 per cent. of the weekly-fed animals did so. This difference was due largely to differences in rate of food consumption. The rate of consumption of the food by the daily-fed groups increased during the progress of the experiment. The sheep receiving the larger amounts of roughage took longer to consume the daily ration. The sheep in the weekly-fed groups ate the week's ration in 4 – 4½ days and occasionally took half a day longer. The death rate in the daily-fed groups was 30.2 per cent, compared with 11.8 per cent. in the meekly-fed group. The deaths occurred mainly (72 per cent.) in the sheep which had lost 40 per cent. or more of their initial body weight. Mean wool production from the daily-fed sheep ranged from 6.73 lb. to 6.94 lb. per sheep, and from the weekly-fed groups from 7.19 lb. to 7.57 lb. Regain of body weight after the termination of the experiment on the low diet was studied. Groups which were retained in pens and fed ad lib. gained steadily in weight and maintained a considerable lead over those which had been turned out to graze. In a group of sheep at pasture there was a close positive correlation between the loss suffered in body weight on the experimental low diet and the subsequent improvement at pasture. The rate and magnitude of subsequent regain of weight were not influenced by the proportion of roughage in the experimental diet or by the origin of the sheep from the daily-fed and weekly-fed groups. An inverse relationship between atmospheric temperatures and body-weight changes was observed. The experiments showed that daily feeding of the sheep at levels sufficient for survival was less satisfactory than weekly feeding at the same level. The practical importance of the results is discussed briefly.