Low Carbohydrate-Diet Scores and Long-term Risk of Type 2 Diabetes Among Women With a History of Gestational Diabetes Mellitus: A Prospective Cohort Study.

Low-carbohydrate diets (LCDs) may improve short-term glycemic control in patients with gestational diabetes mellitus (GDM), but the long-term effect on progression from GDM to type 2 diabetes mellitus (T2DM) is unknown. We aimed to examine the long-term risk of T2DM in association with a low-carbohydrate dietary pattern among women with a history of GDM. Overall, 4,502 women with a history of GDM from the Nurses' Health Study II (NHSII) cohort, as part of the Diabetes & Women's Health (DWH) study, were followed up from 1991 to 2011. Overall, animal, or vegetable LCD scores, which represent adherence to different low-carbohydrate dietary patterns, were calculated using diet intake information assessed every 4 years since 1991 by validated food-frequency questionnaires. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CIs. We documented 722 incident cases of T2DM during 68,897 person-years of observation. The multivariable-adjusted HRs (95% CIs) of T2DM, comparing the highest with lowest quintiles, were 1.36 (1.04-1.78) for overall LCD score (P = 0.003 for trend), 1.40 (1.06-1.84) for animal LCD score (P = 0.004 for trend), and 1.19 (0.91-1.55) for vegetable LCD score (P = 0.50 for trend). Among women with a history of GDM, a low-carbohydrate dietary pattern, particularly with high protein and fat intake mainly from animal-source foods, is associated with higher T2DM risk, whereas a low-carbohydrate dietary pattern with high protein and fat intake from plant-source foods is not significantly associated with risk of T2DM.

Bao W ，Li S ，Chavarro JE ，Tobias DK ，Zhu Y ，Hu FB ，Zhang C ... -  《-》

Prepregnancy low-carbohydrate dietary pattern and risk of gestational diabetes mellitus: a prospective cohort study.

Low-carbohydrate diets (LCDs) have been vastly popular for weight loss. The association between a low-carbohydrate dietary pattern and risk of gestational diabetes mellitus (GDM) remains unknown. We aimed to prospectively examine the association of 3 prepregnancy low-carbohydrate dietary patterns with risk of GDM. We included 21,411 singleton pregnancies in the Nurses' Health Study II. Prepregnancy LCD scores were calculated from validated food-frequency questionnaires, including an overall LCD score on the basis of intakes of carbohydrate, total protein, and total fat; an animal LCD score on the basis of intakes of carbohydrate, animal protein, and animal fat; and a vegetable LCD score on the basis of intakes of carbohydrate, vegetable protein, and vegetable fat. A higher score reflected a higher intake of fat and protein and a lower intake of carbohydrate, and it indicated closer adherence to a low-carbohydrate dietary pattern. RRs and 95% CIs were estimated by using generalized estimating equations with log-binomial models. We documented 867 incident GDM pregnancies during 10 y follow-up. Multivariable-adjusted RRs (95% CIs) of GDM for comparisons of highest with lowest quartiles were 1.27 (1.06, 1.51) for the overall LCD score (P-trend = 0.03), 1.36 (1.13, 1.64) for the animal LCD score (P-trend = 0.003), and 0.84 (0.69, 1.03) for the vegetable LCD score (P-trend = 0.08). Associations between LCD scores and GDM risk were not significantly modified by age, parity, family history of diabetes, physical activity, or overweight status. A prepregnancy low-carbohydrate dietary pattern with high protein and fat from animal-food sources is positively associated with GDM risk, whereas a prepregnancy low-carbohydrate dietary pattern with high protein and fat from vegetable food sources is not associated with the risk. Women of reproductive age who follow a low-carbohydrate dietary pattern may consider consuming vegetable rather than animal sources of protein and fat to minimize their risk of GDM.

Bao W ，Bowers K ，Tobias DK ，Olsen SF ，Chavarro J ，Vaag A ，Kiely M ，Zhang C ... -  《-》

Pre-pregnancy dietary carbohydrate quantity and quality, and risk of developing gestational diabetes: the Australian Longitudinal Study on Women's Health.

Looman M ，Schoenaker DAJM ，Soedamah-Muthu SS ，Geelen A ，Feskens EJM ，Mishra GD ... -  《-》

Long-term risk of type 2 diabetes in relation to habitual iron intake in women with a history of gestational diabetes: a prospective cohort study.

An iron overload may induce pancreatic islet damage and increase risk of diabetes. Women with a history of gestational diabetes mellitus (GDM) are at high risk of developing type 2 diabetes mellitus (T2DM) after pregnancy. We aimed to examine the association of habitual iron intake with long-term risk of T2DM in this high-risk population. We included 3976 women with a history of GDM from the Nurses' Health Study II cohort as part of the ongoing Diabetes & Women's Health Study. The women were followed up through 2009. Iron intake was assessed with the use of a validated food-frequency questionnaire in 1991 and every 4 y thereafter. We used Cox proportional hazards models to estimate HRs and 95% CIs. We documented 641 incident T2DM cases during 57,683 person-years of observation. Adjusted HRs for T2DM for the highest quartile compared with the lowest quartile were 1.64 (95% CI: 1.20, 2.25; P-trend = 0.02) for total iron intake and 1.80 (95% CI: 1.18, 2.74; P-trend = 0.005) for dietary heme iron intake. In addition, women who consumed ≥30.0 mg supplemental Fe/d, compared with nonusers, had an adjusted HR of 1.83 (95% CI: 1.25, 2.70; P-trend = 0.002). In women with a history of GDM, greater intakes of total iron, dietary heme iron, and supplemental iron were associated with higher risk of T2DM.

Bao W ，Chavarro JE ，Tobias DK ，Bowers K ，Li S ，Hu FB ，Zhang C ... -  《-》

Maternal dietary pattern characterised by high protein and low carbohydrate intake in pregnancy is associated with a higher risk of gestational diabetes mellitus in Chinese women: a prospective cohort study.

Zhou X ，Chen R ，Zhong C ，Wu J ，Li X ，Li Q ，Cui W ，Yi N ，Xiao M ，Yin H ，Xiong G ，Han W ，Hao L ，Yang X ，Yang N ... -  《-》