***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The objective of the present study was to investigate whether weight loss is associated with changes in serum concentrations of lutein ( L ) and zeaxanthin ( Z ) , and /or macular pigment optical density ( MPOD ) . We recruited 104 overweight subjects into this r and omised controlled weight loss study . For the intervention group ( I group ) , weight was assessed weekly and body composition , including BMI ( kg/m2 ) and body fat ( kg and percentage ) , was assessed at baseline , 6 and 12 months . Weight loss was encouraged using dietary and exercise programmes .  MPOD was measured by heterochromatic flicker photometry and serum concentrations of L and Z by HPLC ( at baseline , 1 , 3 , 6 and 12 months ) . The control ( C ) group was assessed at baseline and 12 months . Repeated- measures ANOVA ( RMA ) demonstrated significant weight loss in the I group over the study period ( P = 0·000 ) . There was no significant weight change in the C group ( P = 0·993 ) . RMA of dietary L and Z , serum L and Z , and MPOD demonstrated no significant time or time × group interaction effect in any of these parameters ( P>0·05 for all ) , with the exception of a significant decrease in the dietary intake of Z seen in both groups , over the study period ( P < 0·05 ) . There was a positive and significant relationship between body fat loss ( kg ) and increase in serum concentrations of L in the I group ( r 0·521 ; P = 0·006 ) . Our finding that a reduction in body composition ( e.g. fat mass ) is related to increases in serum concentrations of L is consistent with the hypothesis that body fat acts as a reservoir for this carotenoid , and that weight loss can positively influence circulating carotenoid levels The effects of caloric restriction and exercise on body composition , resting metabolic rate ( RMR ) , and maximal oxygen uptake ( VO2 max ) were studied for 16 wk in 26 premenopausal obese women .  Exercise ( X ) vs nonexercise ( NX ) was crossed with a low-fat , ad libitum-carbohydrate ( AL ) diet vs a restricted ( R ) ( 800 kcal ) low-fat , high-carbohydrate diet in a 2 x 2 factorial design . Subjects were r and omly assigned to one of the four treatment groups . Body-weight and percent-fat losses were significant ( p less than 0.05 ) in all groups but greater in subjects assigned to the R diet ( p less than 0.05 ) and /or X ( p less than 0.10 ) groups . Exercise increased ( p less than 0.01 ) VO2 max but neither exercise nor diet influenced fat-free mass or RMR ( kcal.m-2.h-1 ) , both of which remained unchanged over time . A program similar to that followed by the ALX group is recommended for long-term weight control and overall health This study examined the interaction of 2 diets ( high protein , reduced carbohydrates vs. low protein , high carbohydrates ) with exercise on body composition and blood lipids in women ( n = 48 , approximately 46 y old , BMI = 33 kg/m(2 ) ) during weight loss . The study was a 4-mo weight loss trial using a 2 x 2 block design ( Diet x Exercise ) . Diets were equal in total energy ( 7.1 MJ/d ) and lipids ( approximately 30 % energy intake ) but differed in protein content and the ratio of carbohydrate : protein at 1.6 g/(kg . d ) and < 1.5 ( PRO group ) vs. 0.8 g/(kg . d ) and > 3.5 ( CHO group ) , respectively . Exercise comparisons were lifestyle activity ( control ) vs. a supervised exercise program ( EX : 5 d/wk walking and 2 d/wk resistance training ) . Subjects in the PRO and PRO + EX groups lost more total weight and fat mass and tended to lose less lean mass ( P = 0.10 ) than the CHO and CHO + EX groups . Exercise increased loss of body fat and preserved lean mass . The combined effects of diet and exercise were additive for improving body composition . Serum lipid profiles improved in all groups , but changes varied among diet treatments . Subjects in the CHO groups had larger reductions in total cholesterol and LDL cholesterol , whereas subjects in the PRO groups had greater reductions in triacylglycerol and maintained higher concentrations of HDL cholesterol . This study demonstrated that a diet with higher protein and reduced carbohydrates combined with exercise additively improved body composition during weight loss , whereas the effects on blood lipids differed between diet treatments To test the benefits of aerobic exercise and dietary carbohydrate during reduced-energy feeding , 23 obese women ( 44 + /- 4 % fat ) were r and omly assigned to either aerobic exercise ( Ex ) or no exercise ( Nx ) , and to a low-fat ( LF ) or low-carbohydrate ( LC ) reducing diet ( 5.00 + /- 0.56 MJ/d ) for 12 wk . Changes in body composition , postabsorptive resting metabolic rate ( RMR ) , thermic effect of a meal ( TEM ) , and total daily energy expenditure ( TDEE ) were measured by respiratory gas exchange and doubly labeled water . Significant effects of Ex included a greater loss of fat mass ( Ex : -8.8 + /- 2.1 vs Nx : -6.1 + /- 2.3 kg , P = 0.008 ) and maintenance of TDEE ( Ex : + 0.07 + /- 1.23 vs Nx : -1.46 + /- 1.04 MJ/d , P = 0.004 ) , due to a difference in physical activity ( Ex : + 0.75 + /- 1.06 vs Nx : -0.61 + /- 1.03 MJ/d , P = 0.006 ) , which was not attributable solely to the Ex sessions . RMR in both groups decreased comparably ( -0.54 MJ/d ) , and TEM ( % of meal ) did not change . Diet composition did not significantly influence body composition or energy expenditure changes , but a greater weight loss was observed after the LC than after the LF ( -10.6 + /- 2.0 vs -8.1 + /- 3.0 kg , P = 0.037 ) diet . The addition of aerobic exercise to a low-energy diet was beneficial in the treatment of moderate obesity because of its favorable effects on body composition , physical activity , and TDEE The effects of severe energy restriction alone ( 2.0 MJ/d for 4 wk and subsequently 3.5 MJ/d for 4 wk ) or energy restriction plus moderate exercise on energy balance were studied in 20 healthy obese women . Subjects aged 25 - 50 y were matched on the basis of body mass index and percentage body fat and r and omly assigned to diet alone ( D ) or diet and exercise ( DE ) for 8 wk . DE result ed in a significantly increased loss of fat mass compared with D ( 7.8 + /- 0.8 compared with 5.5 + /- 0.8 kg ; P < 0.05 ) . The average daily metabolic rate measured with doubly labeled water decreased with both treatments , with no differences between the treatments . Energy balance data show that the DE treatment result ed in a significantly greater energy deficit than the D treatment . The relative contribution of fat to energy expenditure during exercise was significantly enhanced by DE treatment whereas it did not change after D. The energy expended on physical activity was not changed at the end of both treatments , with no differences between the two groups . The unchanged energy expended on physical activity indicates that DE might be accompanied by partial compensation of daily physical activities outside the training for the energy expended during the training . The energy deficit due to energy restriction alone was not compensated by a decrease in free-living daily physical activities . Addition of moderate exercise to an energy-restriction program in obese women has advantages with respect to changes in body composition , energy expenditure , and substrate utilization The goal of this study was to evaluate the effect of diets that were equally low in energy but widely different in relative amounts of fat and carbohydrate on body weight during a 6-wk period of hospitalization . Consequently , 43 adult , obese persons were r and omly assigned to receive diets containing 4.2 MJ/d ( 1000 kcal/d ) composed of either 32 % protein , 15 % carbohydrate , and 53 % fat , or 29 % protein , 45 % carbohydrate , and 26 % fat . There was no significant difference in the amount of weight loss in response to diets containing either 15 % ( 8.9 + /- 0.6 kg ) or 45 % ( 7.5 + /- 0.5 kg ) carbohydrate . Furthermore , significant decreases in total body fat and waist-to-hip circumference were seen in both groups , and the magnitude of the changes did not vary as a function of diet composition . Fasting plasma glucose , insulin , cholesterol , and triacylglycerol concentrations decreased significantly in patients eating low-energy diets that contained 15 % carbohydrate , but neither plasma insulin nor triacylglycerol concentrations fell significantly in response to the higher-carbohydrate diet . The results of this study showed that it was energy intake , not nutrient composition , that determined weight loss in response to low-energy diets over a short time period This study examined the effects of calorie alternation and exercise on weight loss .  Moderately obese women ( 130 - 160 % of ideal body weight ) were r and omly assigned to an alternating- or constant-calorie diet with or without aerobic exercise . Both diets provided an average of 1200 kcal/d over a 12-wk period ; daily intake of subjects in the alternating-diet condition varied in a prescribed pattern from 600 to 1800 kcal/d . Exercising subjects walked 5 d/wk . All subjects participated in an intensive outpatient behavior-modification program . At the end of the study , exercised subjects had greater reductions in body weight and body fat percentage than did nonexercised subjects . The type of caloric restriction did not affect weight or fat loss . Changes in resting metabolic rate did not differ among groups . Alternating calories was neither beneficial nor detrimental as a weight-loss strategy whereas exercise was clearly beneficial in weight-loss therapy BACKGROUND The impact of a 6-month lifestyle change intervention on cardiovascular risk factors in obese , sedentary , postmenopausal women was examined . A secondary aim of this investigation was to determine whether the addition of self-control skills training to an empirically supported lifestyle change intervention would result in greater cardiovascular risk reduction . METHODS Forty-four women were r and omly assigned to receive either a lifestyle change or a lifestyle change with self-control skills intervention . Pretreatment and posttreatment weight loss , body composition , physical activity , cardiorespiratory fitness , diet , blood pressure ( BP ) , blood lipids , and psychosocial functioning were assessed . Also , at 1-year posttreatment , weight loss , body composition , self-reported physical activity , and psychosocial functioning were assessed . RESULTS The women significantly increased their physical activity ( + 39.6 % ) and cardiorespiratory fitness ( + 13.5 % ) and reduced their body weight ( -6.5 % ) , fat mass ( -7.4 % ) , body fat ( -2.4 % ) , BP ( SBP -6.2 % , DBP -9.2 % ) , total cholesterol ( -7.4 % ) , triglycerides ( -16.5 % ) , and low-density lipoprotein ( LDL ) cholesterol ( 9.1 % ) and improved their diet ( p < 0.05 ) . At the 1-year follow-up , women had regained approximately 63 % of their posttreatment weight loss ( p < 0.05 ) , but had maintained their previous increases in physical activity . Additionally , there were no significant changes in fat free mass , body fat , anxiety , or depression between the end of treatment and 1-year posttreatment . The addition of self-control skills training did not significantly improve cardiovascular risk reduction . CONCLUSIONS Lifestyle change interventions may be an effective means for reducing cardiovascular risk in obese , sedentary , postmenopausal women . However , greater attention should be devoted to the maintenance of these positive lifestyle changes Context Low-carbohydrate weight reduction diets are popular despite a dearth of data on long-term efficacy and adverse effects . Contribution Community-dwelling hyperlipidemic persons were r and omly assigned to either a low-carbohydrate , ketogenic diet or a low-fat , low-cholesterol , reduced-calorie diet for 24 weeks . Compared to the low-fat group , patients in the low-carbohydrate group lost more weight , had a greater decrease in triglyceride levels , and had higher high-density lipoprotein cholesterol levels . Levels of low-density lipoprotein cholesterol remained stable in both groups . Side effects were more common in the low-cholesterol group but were generally mild . Caution s While the study suggests the efficacy and relative safety of the low-cholesterol diet , the high dropout rate , self-directed adherence to the diet , and relatively short observation period challenge the generalizability of the findings . The Editors As the prevalence of obesity has increased over the past 20 years ( 1 ) , the difficulties faced by overweight patients and their health care practitioners have become apparent . Fewer than 25 % of Americans who attempt to lose weight actually reduce caloric intake and increase exercise as currently recommended ( 2 ) . Persons who successfully 
    Output:
    
Nearly all weight or BMI and body composition measures agreed .
Since body fat is the most metabolically harmful tissue type , it may be a more meaningful measure of health change .