***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 Minnesota Coronary Survey was a 4.5-year , open enrollment , single end-time , double-blind , r and omized clinical trial that was conducted In six Minnesota state mental hospitals and one nursing home . It Involved 4393 Institutionalized men and 4664 Institutionalized women . The trial compared the effects of a 39 % fat control diet ( 18 % saturated fat , 5 % polyunsaturated fat , 16 % monounsaturated fat , 446 mg dietary cholesterol per day ) with a 38 % fat treatment diet ( 9 % saturated fat , 15 % polyunsaturated fat , 14 % monounsaturated fat , 166 mg dietary cholesterol per day ) on serum cholesterol levels and the Incidence of myocardlal Infa rct ions , sudden deaths , and all-cause mortality . The mean duration of time on the diets was 384 days , with 1568 subjects consuming the diet for over 2 years . The mean serum cholesterol level In the pre-admission period was 207 mg/dl , falling to 175 mg/dl in the treatment group and 203 mg/dl In the control group . For the entire study population , no differences between the treatment and control groups were observed for cardiovascular events , cardiovascular deaths , or total mortality . A favorable trend for all these end-points occurred In some younger age groups Background — The bulk of cardiovascular disease risk is not explained by traditional risk factors . Recent advances in mass spectrometry allow the identification and quantification of hundreds of lipid species . Molecular lipid profiling by mass spectrometry may improve cardiovascular risk prediction . Methods and Results — Lipids were extracted from 685 plasma sample s of the prospect i ve population -based Bruneck Study ( baseline evaluation in 2000 ) . One hundred thirty-five lipid species from 8 different lipid classes were profiled by shotgun lipidomics with the use of a triple-quadrupole mass spectrometer . Levels of individual species of cholesterol esters ( CEs ) , lysophosphatidylcholines , phosphatidylcholines , phosphatidylethanolamines ( PEs ) , sphingomyelins , and triacylglycerols ( TAGs ) were associated with cardiovascular disease over a 10-year observation period ( 2000–2010 , 90 incident events ) . Among the lipid species with the strongest predictive value were TAGs and CEs with a low carbon number and double-bond content , including TAG(54:2 ) and CE(16:1 ) , as well as PE(36:5 ) ( P=5.1 × 10−7 , 2.2 × 10−4 , and 2.5 × 10−3 , respectively ) . Consideration of these 3 lipid species on top of traditional risk factors result ed in improved risk discrimination and classification for cardiovascular disease ( cross-vali date d & Dgr;C index , 0.0210 [ 95 % confidence interval , 0.0010 - 0.0422 ] ; integrated discrimination improvement , 0.0212 [ 95 % confidence interval , 0.0031 - 0.0406 ] ; and continuous net reclassification index , 0.398 [ 95 % confidence interval , 0.175 - 0.619 ] ) . A similar shift in the plasma fatty acid composition was associated with cardiovascular disease in the UK Twin Registry ( n=1453 , 45 cases ) . Conclusions — This study applied mass spectrometry-based lipidomics profiling to population -based cohorts and identified molecular lipid signatures for cardiovascular disease . Molecular lipid species constitute promising new biomarkers that outperform the conventional biochemical measurements of lipid classes currently used in clinics Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more To assess the effect of dietary reduction of plasma cholesterol concentrations on coronary atherosclerosis , we set up a r and omised , controlled , end-point-blinded trial based on quantitative image analysis of coronary angiograms in patients with angina or past myocardial infa rct ion . Another intervention group received diet and cholestyramine , to determine the effect of a greater reduction in circulating cholesterol concentrations . 90 men with coronary heart disease ( CHD ) , who had a mean ( SD ) plasma cholesterol of 7.23 ( 0.77 ) mmol/l were r and omised to receive usual care ( U , controls ) , dietary intervention ( D ) , or diet plus cholestyramine ( DC ) , with angiography at baseline and at 39 ( SD 3.5 ) months . Mean plasma cholesterol during the trial period was 6.93 ( U ) , 6.17 ( D ) , and 5.56 ( DC ) mmol/l . The proportion of patients who showed overall progression of coronary narrowing was significantly reduced by both interventions ( U 46 % , D 15 % , DC 12 % ) , whereas the proportion who showed an increase in luminal diameter rose significantly ( U 4 % , D 38 % , DC 33 % ) . The mean absolute width of the coronary segments ( MAWS ) studied decreased by 0.201 mm in controls , increased by 0.003 mm in group D , and increased by 0.103 mm in group DC ( p less than 0.05 ) , with improvement also seen in the minimum width of segments , percentage diameter stenosis , and edge-irregularity index in intervention groups . The change in MAWS was independently and significantly correlated with LDL cholesterol concentration and LDL/HDL cholesterol ratio during the trial period . Both interventions significantly reduced the frequency of total cardiovascular events . Dietary change alone retarded overall progression and increased overall regression of coronary artery disease , and diet plus cholestyramine was additionally associated with a net increase in coronary lumen diameter . These findings support the use of a lipid-lowering diet , and if necessary of appropriate drug treatment , in men with CHD who have even mildly raised serum cholesterol concentrations The study deals with 412 men , aged 30 to 64 years , r and omized 1 to 2 years after a first myocardial infa rct ion . For the experimental group a diet low in saturated fats and cholesterol , and high in polyunsaturated fats was recommended . After 5 years , as reported previously , the incidence of fatal and nonfatal myocardial reinfa rct ion was found to be significantly reduced . “ Sudden death ” was uninfluenced . Major coronary heart disease ( CHD ) relapses , including fatal and nonfatal events ( MI ) , were significantly reduced ( P = 0.05).After 11 years , death from all causes had occurred in 101 of the original dieters and 108 controls . A significantly reduced myocardial infa rct ion mortality in the original diet group was found ( 32 versus 57 , P = 0.004 ) . The total number of coronary deaths ( fatal myocardial infa rct ion and sudden death ) was 79 in the diet group and 94 in the control group ( P = 0.097).The CHD mortality was correlated with age , serum cholesterol level , blood pressure , body weight , smoking habits , and a combination of these risk factors STUDY OBJECTIVE To investigate the prevalence and nature of low energy reporting in a dietary survey of British adults over 65 years of age . DESIGN R and omly selected cross sectional sample of 2060 British adults over 65 years . Four day weighed food diaries and question naires on health , lifestyle and socioeconomic characteristics . SETTING Great Britain . PARTICIPANTS 539 women and 558 men over 65 years who were free living and completed four day food diaries .  MAIN RESULTS A high proportion of men and women were classified as low energy reporters ( LERs ) . Reported consumption of full fat dairy products , sugar and sweet foods , and alcoholic drinks differed most between LERs and non-LERs . Among LERs , reported protein and starch intakes were higher , fat , sugar and alcohol intakes were lower . LERs of either sex were more likely to be obese , male LERs were also more likely to belong to the manual social classes . CONCLUSIONS The high level of low energy reporting probably result ed from a coalescence of factors such as the weighed diary methodology and a reluctance to report consumption of unhealthy foods . The use of validatory biomarkers such as doubly labelled water needs to be more widespread A controlled intervention trial , with the purpose of testing the hypothesis that the incidence of coronary heart disease ( CHD ) could be decreased by the use of a serum-cholesterol-lowering ( SCL ) diet , was carried out in two mental hospitals near Helsinki in 1959 - 71 . The subjects were hospitalized middle-aged women . One of the hospitals received the SCL diet , ie a diet low in saturated fats and cholesterol and relatively high in poly-unsaturated fats , while the other served as the control with a normal hospital diet . Six years later the diets were reversed , and the trial was continued another six years . The use of the SCL diet was associated with markedly lowered serum cholesterol values . The incidence of CHD , as measured by the appearance of certain electrocardiographic patterns and by the occurrence of coronary deaths , was in both hospitals during the SCL-diet periods lower than during the normal-diet periods . The differences , however , failed to reach statistical significance . An examination of a number of potential confounding variables indicated that the changes in them were small and failed to account for the reduction in the incidence of CHD . Although the results of this trial do not permit firm conclusions , they support the idea that also among female population s the SCL diet exerts a preventive effect on CHD A controlled intervention trial , with the purpose of testing the hypothesis that the incidence of coronary heart disease ( CHD ) could be decreased by the use of serum-cholesterol-lowering ( SCL ) diet , was carried out in 2 mental hospitals near Helsinki in 1959 - -71 . The subjects were hospitalized middle-aged men . One of the hospitals received the SCL diet , i.e. a diet low in saturated fats and cholesterol and relatively high in polyunsaturated fats , while the other served as the control with a normal hospital diet . Six years later the diets were reversed , and the trial was continued another 6 years . The use of the SCL diet was associated with markedly lowered serum-cholesterol values . The incidence of CHD , as measured by the appearance of certain electrocardiographic patterns and by the occurrence of coronary deaths , was in both hospitals during the SCL-diet periods about half that during the normal-diet periods . An examination of a number of potential confounding variables indicated that the changes in them were small and failed to account for the considerable reduction in the incidence of CHD . It is concluded that the use of the serum-cholesterol-lowering diet exerted a substantial preventive effect on CHD A r and omised controlled trial with a factorial design was done to examine the effects of dietary intervention in the secondary prevention of myocardial infa rct ion ( MI ) . 2033 men who had recovered from MI were allocated to receive or not to receive advice on each of three dietary factors : a reduction in fat intake and an increase in the ratio of polyunsaturated to saturated fat , an increase in fatty fish intake , and an increase in cereal fibre intake . The advice on fat was not associated with any difference in mortality , perhaps because it produced only a small reduction ( 3 - 4 % ) in serum cholesterol . The subjects advised to eat fatty fish had a 29 % reduction in 2 year all-cause mortality compared with those not so advised . This effect , which was significant , was not altered by adjusting for ten potential confounding factors . Subjects given fibre advice had a slightly higher mortality than other subjects ( not significant ) . The 2 year incidence of reinfa rct ion plus death from ischaemic heart disease was not significantly affected by any of the dietary regimens . A modest intake of fatty fish ( two or three portions per week ) may reduce mortality in men who have recovered from MI 
    Output:
    
Mean serum cholesterol levels decreased in all intervention groups and all but one control group .
The reductions in mean serum cholesterol levels were significantly greater in the intervention groups ; this did not result in significant differences in CHD or all-cause mortality .
CONCLUSIONS The current available evidence found no significant difference in all-cause mortality or CHD mortality , result ing from the dietary fat interventions .
RCT evidence currently available does not support the current dietary fat guidelines .