King Grub
2013-08-14, 14:53
In this controlled, parallel-group feeding trial, we examined the impact of carbohydrate (CHO) intake and glycemic index (GI) on glucose and lipid metabolism during refeeding after weight loss. Healthy men (n = 32 total, age: 25.5 ± 3.9 y, BMI: 23.5 ± 2.0 kg/m2) overconsumed diets containing either 50 or 65% CHO for 1 wk (+50% of energy requirements) and then underwent 3 wk of calorie restriction (CR; −50%) followed by 2 wk of overconsuming (refeeding, +50%) the same diet but with either a low or high GI (40 vs.70 during CR, 41 vs.74 during refeeding) so that glycemic load (GL; dietary CHO content x GI) differed between groups during all phases. Glucose profiles were assessed by continuous interstitial glucose monitoring, insulin sensitivity (IS) by fasting blood sampling, oral glucose tolerance test (OGTT) and hyperinsulinemic-euglycemic clamp, and liver fat by MRI. Daytime area under the curve-glucose during refeeding was higher with high compared with low GI (P = 0.01) and 65% compared with 50% CHO intake (P = 0.05) and correlated with dietary GL (r = 0.71; P < 0.001). IS increased with CR and decreased again with refeeding in all groups. The decrease in OGTT-derived IS was greater with high- than with low-GI diets (−41 vs. −15%; P-interaction = 0.01) and correlated with dietary GL during refeeding (r = −0.51; P < 0.01). Serum triglycerides (TGs) and liver fat also improved with CR (−17 ± 38 mg/dL and −1.1 ± 1.3%; P < 0.05 and <0.001) and increased again with refeeding (+48 ± 48 mg/dL and +2.2 ± 1.6%; P < 0.001). After refeeding, serum TGs and liver fat were elevated above baseline values with 65% CHO intake only (+59.9 ± 37.5 mg/dL and +1.1 ± 1.7%, P-interaction <0.001 and <0.05). In conclusion, a diet low in GI and moderate in CHO content (i.e., low GL) may have health benefits by positively affecting daylong glycemia, IS, and liver fat.
Carbohydrate Quality and Quantity Affect Glucose and Lipid Metabolism during Weight Regain in Healthy Men. J. Nutr. 2013 August 14, 2013.
http://jn.nutrition.org/content/early/2013/08/13/jn.113.179390.full.pdf+html
Carbohydrate Quality and Quantity Affect Glucose and Lipid Metabolism during Weight Regain in Healthy Men. J. Nutr. 2013 August 14, 2013.
http://jn.nutrition.org/content/early/2013/08/13/jn.113.179390.full.pdf+html