There is low to high ( majority moderate ) certainty for small improvements of unclear clinical importance in plasma glucose , triglycerides , and HDL concentrations favoring low-carbohydrate food at half of the prespecified time points .
There was little to no difference in LDL concentration or any of the secondary outcomes ( body weight , waist circumference , blood pressure , quality of life ) in response to either of the diets ( very-low- to high-certainty evidence ) .
Conclusions Currently available data provide low- to moderate-certainty evidence that dietary carbohydrate restriction to a maximum of 40 % yields slightly better metabolic control of uncertain clinical importance than reduction in fat to a maximum of 30 % in people with T2D .
Background It remains uncertain which diet is best for people with type 2 diabetes ( T2D ) .
Objective We compared the effects of dietary carbohydrate restriction with fat restriction on markers of metabolic syndrome and quality of life in people with T2D .
The national cholesterol education program diet vs a diet lower in carbohydrates and higher in protein and monounsaturated fat: a randomized trial.
BACKGROUND In the United States , obesity is a major clinical and public health problem causing diabetes , dyslipidemia , and hypertension , as well as increasing cardiovascular and total mortality . Dietary restrictions of calories and saturated fat are beneficial . However , it remains unclear whether replacement of saturated fat with carbohydrates ( as in the US National Cholesterol Education Program [ NCEP ] diet ) or protein and monounsaturated fat ( as in our isocaloric modified low-carbohydrate [ MLC ] diet , which is lower in total carbohydrates but higher in protein , monounsaturated fat , and complex carbohydrates ) is optimal . METHODS We r and omized 60 participants ( 29 women and 31 men ) to the NCEP or the MLC diet  and evaluated them every 2 weeks for 12 weeks . They were aged 28 to 71 years ( mean age , 44 years in the NCEP and 46 years in the MLC group ) . A total of 36 % of participants from the NCEP group and 35 % from the MLC group had a body mass index ( calculated as weight in kilograms divided by the square of height in meters ) greater than 27 . The primary end point was weight loss , and secondary end points were blood lipid levels and waist-to-hip ratio . RESULTS Weight loss was significantly greater in the MLC ( 13.6 lb ) than in the NCEP group ( 7.5 lb ) , a difference of 6.1 lb ( P = .02 ) . There were no significant differences between the groups for total , low density , and high-density lipoprotein cholesterol , triglycerides , or the proportion of small , dense low-density lipoprotein particles . There were significantly favorable changes in all lipid levels within the MLC but not within the NCEP group . Waist-to-hip ratio was not significantly reduced between the groups ( P = .27 ) , but it significantly decreased within the MLC group ( P = .009 ) . CONCLUSIONS Compared with the NCEP diet , the MLC diet , which is lower in total carbohydrates but higher in complex carbohydrates , protein , and monounsaturated fat , caused significantly greater weight loss over 12 weeks . There were no significant differences between the groups in blood lipid levels , but favorable changes were observed within the MLC diet group
There is low to high ( majority moderate ) certainty for small improvements of unclear clinical importance in plasma glucose , triglycerides , and HDL concentrations favoring low-carbohydrate food at half of the prespecified time points .
There was little to no difference in LDL concentration or any of the secondary outcomes ( body weight , waist circumference , blood pressure , quality of life ) in response to either of the diets ( very-low- to high-certainty evidence ) .
Conclusions Currently available data provide low- to moderate-certainty evidence that dietary carbohydrate restriction to a maximum of 40 % yields slightly better metabolic control of uncertain clinical importance than reduction in fat to a maximum of 30 % in people with T2D .
Background It remains uncertain which diet is best for people with type 2 diabetes ( T2D ) .
Objective We compared the effects of dietary carbohydrate restriction with fat restriction on markers of metabolic syndrome and quality of life in people with T2D .