title: Resistant starch from high-amylose maize increases insulin sensitivity in overweight and obese men.
abstract: This study evaluated the effects of 2 levels of intake of high-amylose maize type 2 resistant starch (HAM-RS2) on insulin sensitivity (S(I)) in participants with waist circumference ≥89 (women) or ≥102 cm (men). Participants received 0 (control starch), 15, or 30 g/d (double-blind) of HAM-RS2 in random order for 4-wk periods separated by 3-wk washouts. Minimal model S(I) was assessed at the end of each period using the insulin-modified i.v. glucose tolerance test. The efficacy evaluable sample included 11 men and 22 women (mean ± SEM) age 49.5 ± 1.6 y, with a BMI of 30.6 ± 0.5 kg/m2 and waist circumference 105.3 ± 1.3 cm. A treatment main effect (P = 0.018) and a treatment × sex interaction (P = 0.033) were present. In men, least squares geometric mean analysis for S(I) did not differ after intake of 15 g/d HAM-RS2 (6.90 × 10⁻⁵ pmol⁻¹ · L⁻¹ × min⁻¹) and 30 g/d HAM-RS2 (7.13 × 10⁻⁵ pmol⁻¹ · L⁻¹ × min⁻¹), but both were higher than after the control treatment (4.66 × 10⁻⁵ pmol⁻¹ · L⁻¹ × min⁻¹) (P < 0.05). In women, there was no difference among the treatments (overall least squares ln-transformed mean ± pooled SEM = 1.80 ± 0.08; geometric mean = 6.05 × 10⁻⁵ pmol⁻¹ · L⁻¹ × min⁻¹). These results suggest that consumption of 15-30 g/d of HAM-RS2 improves S(I) in men. Additional research is needed to understand the mechanisms that might account for the treatment × sex interaction observed.
authors.affiliation: Provident Clinical Research and Consulting, Inc., Glen Ellyn, IL, USA. KMaki@ProvidentCRC.com
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Maki
authors.forename: Christine L
authors.initials: CL
authors.lastname: Pelkman
authors.forename: E Terry
authors.initials: ET
authors.lastname: Finocchiaro
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Kelley
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Lawless
authors.forename: Arianne L
authors.initials: AL
authors.lastname: Schild
authors.forename: Tia M
authors.initials: TM
authors.lastname: Rains
mesh_terms: D000328:Adult; D000688:Amylose / Q000032:analysis*; D019440:Anti-Obesity Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000378:metabolism / Q000627:therapeutic use; D015992:Body Mass Index; D018592:Cross-Over Studies; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000009:adverse effects / Q000378:metabolism / Q000627:therapeutic use; D004311:Double-Blind Method; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy* / Q000378:metabolism; D050177:Overweight / Q000178:diet therapy* / Q000378:metabolism; D000084922:Resistant Starch; D012639:Seeds / Q000737:chemistry*; D012727:Sex Characteristics; D013213:Starch / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives / Q000378:metabolism / Q000627:therapeutic use*; D055105:Waist Circumference; D003313:Zea mays / Q000737:chemistry*
chemical_list: D019440:Anti-Obesity Agents; D004040:Dietary Carbohydrates; D000084922:Resistant Starch; C572111:high-amylose maize type 2 resistant starch, maize; D013213:Starch; D000688:Amylose