title: Three-graded stratification of carbohydrate restriction by level of baseline hemoglobin A1c for type 2 diabetes patients with a moderate low-carbohydrate diet.
abstract: BACKGROUND
  A moderate low-carbohydrate diet has been receiving attention in the dietary management of type 2 diabetes (T2DM). A fundamental issue has still to be addressed; how much carbohydrate delta-reduction (Δcarbohydrate) from baseline would be necessary to achieve a certain decrease in hemoglobin A1c (HbA1c) levels.
  
  
  OBJECTIVE
  We investigated the effects of three-graded stratification of carbohydrate restriction by patient baseline HbA1c levels on glycemic control and effects of Δcarbohydrate on decreases in HbA1c levels (ΔHbA1c) in each group.
  
  
  METHODS
  We treated 122 outpatients with T2DM by three-graded carbohydrate restriction according to baseline HbA1c levels (≤ 7.4% for Group 1, 7.5%-8.9% for Group 2 and ≥ 9.0% for Group 3) and assessed their HbA1c levels, doses of anti-diabetic drugs and macronutrient intakes over 6 months.
  
  
  RESULTS
  At baseline, the mean HbA1c level and carbohydrate intake were 6.9 ± 0.4% and 252 ± 59 g/day for Group 1 (n = 55), 8.1 ± 0.4% and 282 ± 85 g/day for Group 2 (n = 41) and 10.6 ± 1.4% and 309 ± 88 g/day for Group 3 (n = 26). Following three-graded carbohydrate restriction for 6 months significantly decreased mean carbohydrate intake (g/day) and HbA1c levels for all patients, from 274 ± 78 to 168 ± 52 g and from 8.1 ± 1.6 to 7.1 ± 0.9% (n = 122, P < 0.001 for both) and anti-diabetic drugs could be tapered. ΔHbA1c and Δcarbohydrate were -0.4 ± 0.4% and -74 ± 69 g/day for Group 1, -0.6 ± 0.9% and -117 ± 78 g/day for Group 2 and -3.1 ± 1.4% and -156 ± 74 g/day for Group 3. Linear regression analysis showed that the greater the carbohydrate intake, the greater the HbA1c levels at baseline (P = 0.001). Also, the greater the reduction in carbohydrate intake (g/day), the greater the decrease in HbA1c levels (P < 0.001), but ΔHbA1c was not significantly influenced by changes in other macronutrient intakes (g/day).
  
  
  CONCLUSIONS
  Three-graded stratification of carbohydrate restriction according to baseline HbA1c levels may provide T2DM patients with optimal objectives for carbohydrate restriction and prevent restriction from being unnecessarily strict.
authors.affiliation: Department of Internal Medicine, Haimoto Clinic, 1-80 Yayoi, Kasugai, Aichi 486-0838, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Haimoto
authors.affiliation: Department of Clinical Nutrition, Haimoto Clinic, 1-80 Yayoi-cho, Kasugai, Aichi 486-0838, Japan.
authors.forename: Tae
authors.initials: T
authors.lastname: Sasakabe
authors.affiliation: Department of Diabetes and Endocrine Internal Medicine, Chubu Rosai Hospital, 10-6-1, Komei-cho, Minato-ku, Nagoya, Aichi 455-8530, Japan.
authors.forename: Takahiko
authors.initials: T
authors.lastname: Kawamura
authors.affiliation: Department of Geriatrics, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Umegaki
authors.affiliation: Department of Cardiac Surgery, Kansai Heart Center, Nara 1-3-3 Ukyo Nara-city, 631-0805, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Komeda
authors.affiliation: Department of Preventive Medicine, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Wakai
keywords: Carbohydrate intake; Hemoglobin A1c; Low-carbohydrate diet; Macronutrient; Stratification; Type 2 diabetes
references.citation: Diabetes Res Clin Pract. 2008 Feb;79(2):350-6
references.pmid: 17980451
references.citation: Diabetes Metab Syndr Obes. 2012;5:283-91
references.pmid: 22924004
references.citation: Prog Lipid Res. 2008 Sep;47(5):307-18
references.pmid: 18396172
references.citation: J Diabetes Investig. 2012 Feb 20;3(1):39-40
references.pmid: 24843544
references.citation: Nutr Metab (Lond). 2008 May 22;5:14
references.pmid: 18495047
references.citation: Ann Intern Med. 2005 Mar 15;142(6):403-11
references.pmid: 15767618
references.citation: Diabetes Res Clin Pract. 1999 May;44(2):137-46
references.pmid: 10414933
references.citation: Diabetes. 2004 Sep;53(9):2375-82
references.pmid: 15331548
references.citation: Diabetes Care. 2012 Feb;35(2):434-45
references.pmid: 22275443
references.citation: Nutr Metab (Lond). 2009 May 06;6:21
references.pmid: 19419563
references.citation: Nutr Metab (Lond). 2008 Dec 19;5:36
references.pmid: 19099589
references.citation: Nutr Metab (Lond). 2006 Mar 23;3:16
references.pmid: 16556307
references.citation: J Am Diet Assoc. 2009 Jul;109(7):1173-8
references.pmid: 19559133
references.citation: Diabetes Metab Syndr Obes. 2011;4:167-74
references.pmid: 21779148
references.citation: Diabetes Metab Syndr Obes. 2012;5:57-74
references.pmid: 22563248
references.citation: Curr Diab Rep. 2011 Apr;11(2):128-35
references.pmid: 21234818
references.citation: Diabet Med. 2006 Jan;23(1):15-20
references.pmid: 16409560
references.citation: Nutr Metab (Lond). 2008 Apr 08;5:9
references.pmid: 18397522
references.citation: N Engl J Med. 2003 May 22;348(21):2082-90
references.pmid: 12761365
references.citation: J Atheroscler Thromb. 2011;18(9):723-34
references.pmid: 21685707
references.citation: JAMA. 2009 Apr 15;301(15):1565-72
references.pmid: 19366776
references.citation: Ann Intern Med. 2010 Aug 3;153(3):147-57
references.pmid: 20679559
references.citation: Nutr Metab (Lond). 2010 Jul 29;7:64
references.pmid: 20670414