***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: BACKGROUND Effects of diet on blood lipids are best known in white men , and effects of type of carbohydrate on triacylglycerol concentrations are not well defined . OBJECTIVE Our goal was to determine the effects of diet on plasma lipids , focusing on subgroups by sex , race , and baseline lipid concentrations . DESIGN This was a r and omized controlled outpatient feeding trial conducted in 4 field centers . The subjects were 436 participants of the Dietary Approaches to Stop Hypertension ( DASH ) Trial [ mean age : 44.6 y ; 60 % African American ; baseline total cholesterol : < or = 6.7 mmol/L ( < or = 260 mg/dL ) ] . The intervention consisted of 8 wk of a control diet , a diet increased in fruit and vegetables , or a diet increased in fruit , vegetables , and low-fat dairy products and reduced in saturated fat , total fat , and cholesterol ( DASH diet ) , during which time subjects remained weight stable . The main outcome measures were fasting total cholesterol , LDL cholesterol , HDL cholesterol , and triacylglycerol . RESULTS Relative to the control diet , the DASH diet result ed in lower total ( -0.35 mmol/L , or -13.7 mg/dL ) , LDL- ( -0.28 mmol/L , or -10.7 mg/dL ) , and HDL- ( -0.09 mmol/L , or -3.7 mg/dL ) cholesterol concentrations ( all P < 0.0001 ) , without significant effects on triacylglycerol . The net reductions in total and LDL cholesterol in men were greater than those in women by 0.27 mmol/L , or 10.3 mg/dL ( P = 0.052 ) , and by 0.29 mmol/L , or 11.2 mg/dL ( P < 0.02 ) , respectively . Changes in lipids did not differ significantly by race or baseline lipid concentrations , except for HDL , which decreased more in participants with higher baseline HDL-cholesterol concentrations than in those with lower baseline HDL-cholesterol concentrations . The fruit and vegetable diet produced few significant lipid changes . CONCLUSIONS The DASH diet is likely to reduce coronary heart disease risk . The possible opposing effect on coronary heart disease risk of HDL reduction needs further study Objectives To estimate 10 year decline in cognitive function from longitudinal data in a middle aged cohort and to examine whether age cohorts can be compared with cross sectional data to infer the effect of age on cognitive decline . Design Prospect i ve cohort study . At study inception in 1985 - 8 , there were 10 308 participants , representing a recruitment rate of 73 % . Setting Civil service departments in London , United Kingdom . Participants 5198 men and 2192 women , aged 45 - 70 at the beginning of cognitive testing in 1997 - 9 . Main outcome measure Tests of memory , reasoning , vocabulary , and phonemic and semantic fluency , assessed three times over 10 years . Results All cognitive scores , except vocabulary , declined in all five age categories ( age 45 - 49 , 50 - 54 , 55 - 59 , 60 - 64 , and 65 - 70 at baseline ) , with evidence of faster decline in older people . In men , the 10 year decline , shown as change/range of test × 100 , in reasoning was −3.6 % ( 95 % confidence interval −4.1 % to −3.0 % ) in those aged 45 - 49 at baseline and −9.6 % ( −10.6 % to −8.6 % ) in those aged 65 - 70 . In women , the corresponding decline was −3.6 % ( −4.6 % to −2.7 % ) and −7.4 % ( −9.1 % to −5.7 % ) . Comparisons of longitudinal and cross sectional effects of age suggest that the latter overestimate decline in women because of cohort differences in education . For example , in women aged 45 - 49 the longitudinal analysis showed reasoning to have declined by −3.6 % ( −4.5 % to −2.8 % ) but the cross sectional effects suggested a decline of −11.4 % ( −14.0 % to −8.9 % ) . Conclusions Cognitive decline is already evident in middle age ( age 45 - 49 ) Depressive symptoms may increase the risk of progressing from mild cognitive impairment ( MCI ) to dementia . Consumption of n-3 PUFA may alleviate both cognitive decline and depression . The aim of the present study was to investigate the benefits of supplementing a diet with n-3 PUFA , DHA and EPA , for depressive symptoms , quality of life ( QOL ) and cognition in elderly people with MCI . We conducted a 6-month double-blind , r and omised controlled trial . A total of fifty people aged > 65 years with MCI were allocated to receive a supplement rich in EPA ( 1·67 g EPA + 0·16 g DHA/d ; n 17 ) , DHA ( 1·55 g DHA + 0·40 g EPA/d ; n 18 ) or the n-6 PUFA linoleic acid ( LA ; 2·2 g/d ; n 15 ) . Treatment allocation was by minimisation based on age , sex and depressive symptoms ( Geriatric Depression Scale , GDS ) . Physiological and cognitive assessment s , question naires and fatty acid composition of erythrocytes were obtained at baseline and 6 months ( completers : n 40 ; EPA n 13 , DHA n 16 , LA n 11 ) . Compared with the LA group , GDS scores improved in the EPA ( P=0·04 ) and DHA ( P=0·01 ) groups and verbal fluency ( Initial Letter Fluency ) in the DHA group ( P=0·04 ) . Improved GDS scores were correlated with increased DHA plus EPA ( r 0·39 , P=0·02 ) . Improved self-reported physical health was associated with increased DHA . There were no treatment effects on other cognitive or QOL parameters . Increased intakes of DHA and EPA benefited mental health in older people with MCI . Increasing n-3 PUFA intakes may reduce depressive symptoms and the risk of progressing to dementia . This needs to be investigated in larger , depressed sample s with MCI BACKGROUND Docosahexaenoic acid ( DHA ) is important for brain function , and its status is dependent on dietary intakes . Therefore , individuals who consume diets low in omega-3 ( n-3 ) polyunsaturated fatty acids may cognitively benefit from DHA supplementation . Sex and apolipoprotein E genotype ( APOE ) affect cognition and may modulate the response to DHA supplementation . OBJECTIVES We investigated whether a DHA supplement improves cognitive performance in healthy young adults and whether sex and APOE modulate the response . DESIGN Healthy adults ( n = 176 ; age range : 18 - 45 y ; nonsmoking and with a low intake of DHA ) completed a 6-mo r and omized , placebo-controlled , double-blind intervention in which they consumed 1.16 g DHA/d or a placebo .  Cognitive performance was assessed by using a computerized cognitive test battery . For all tests , z scores were calculated and clustered into cognitive domains as follows : episodic and working memory , attention , reaction time ( RT ) of episodic and working memory , and attention and processing speed . ANCOVA was conducted with sex and APOE as independent variables . RESULTS RTs of episodic and working memory improved with DHA compared with placebo [ mean difference ( 95 % CI ) : -0.18 SD ( -0.33 , -0.03 SD ) ( P = 0.02 ) and -0.36 SD ( -0.58 , -0.14 SD ) ( P = 0.002 ) , respectively ] . Sex × treatment interactions occurred for episodic memory ( P = 0.006 ) and the RT of working memory ( P = 0.03 ) . Compared with the placebo , DHA improved episodic memory in women [ 0.28 SD ( 0.08 , 0.48 SD ) ; P = 0.006 ] and RTs of working memory in men [ -0.60 SD ( -0.95 , -0.25 SD ) ; P = 0.001 ] . APOE did not affect cognitive function , but there were some indications of APOE × sex × treatment interactions . CONCLUSIONS DHA supplementation improved memory and the RT of memory  in healthy , young adults whose habitual diets were low in DHA  . The response was modulated by sex . This trial was registered at the New Zeal and Clinical Trials Registry ( http://www.anzctr.org.au/default.aspx ) as ACTRN12610000212055 Studies in rodents indicate that diets deficient in omega-3 polyunsaturated fatty acids ( n–3 PUFA ) lower dopamine neurotransmission as measured by striatal vesicular monoamine transporter type 2 ( VMAT2 ) density and amphetamine-induced dopamine release . This suggests that dietary supplementation with fish oil might increase VMAT2 availability , enhance dopamine storage and release , and improve dopamine-dependent cognitive functions such as working memory . To investigate this mechanism in humans , positron emission tomography ( PET ) was used to measure VMAT2 availability pre- and post-supplementation of n–3 PUFA in healthy individuals . Healthy young adult subjects were scanned with PET using [11C]-(+)-α-dihydrotetrabenzine ( DTBZ ) before and after six months of n–3 PUFA supplementation ( Lovaza , 2 g/day containing docosahexaenonic acid , DHA 750 mg/d and eicosapentaenoic acid , EPA 930 mg/d ) . In addition , subjects underwent a working memory task ( n-back ) and red blood cell membrane ( RBC ) fatty acid composition analysis pre- and post-supplementation . RBC analysis showed a significant increase in both DHA and EPA post-supplementation . In contrast , no significant change in [11C]DTBZ binding potential ( BPND ) in striatum and its subdivisions were observed after supplementation with n–3 PUFA . No correlation was evident between n–3 PUFA induced change in RBC DHA or EPA levels and change in [11C]DTBZ BPND in striatal subdivisions . However , pre-supplementation RBC DHA levels was predictive of baseline performance ( i.e. , adjusted hit rate , AHR on 3-back ) on the n-back task ( y = 0.19 + 0.07 , r2 = 0.55 , p = 0.009 ) . In addition , subjects AHR performance improved on 3-back post-supplementation ( pre 0.65±0.27 , post 0.80±0.15 , p = 0.04 ) . The correlation between n-back performance , and DHA levels are consistent with reports in which higher DHA levels is related to improved cognitive performance . However , the lack of change in [11C]DBTZ BPND indicates that striatal VMAT2 regulation is not the mechanism of action by which n–3 PUFA improves cognitive performance Abstract . The effects of capsules containing 60 mg of a st and ardised extract of Ginkgo biloba ( GK501 ) and 100 mg of a st and ardised extract of Panax ginseng ( G115 ) on various aspects of cognitive function were assessed in healthy middle-aged volunteers . A double blind , placebo controlled , 14 week , parallel group , repeated assessment , multi-centre trial of two dosing regimens , 160 mg b.i.d . and 320 mg o.d . was conducted . Two hundred and fifty-six healthy middle-aged volunteers successfully completed the study . On various study days ( weeks 0 , 4 , 8 , 12 and 14 ) the volunteers performed a selection of tests of attention and memory from the Cognitive Drug Research computerised cognitive assessment system prior to morning dosing and again , at 1 , 3 and 6 h later . The volunteers also completed question naires about mood states , quality of life and sleep quality . The Ginkgo/ginseng combination was found significantly to improve an Index of Memory Quality , supporting a previous finding with the compound . This effect represented an average improvement of 7.5 % and reflected improvements to a number of different aspects of memory , including working and long-term memory . This enhancement to memory was seen throughout the 12-week dosing period and also after a 2-week washout . This represents the first substantial demonstration of improvements to the memory of healthy middle-aged volunteers produced by a phytopharmaceutical The omega-3 fatty acid docosahexaenoic acid ( DHA ) is essential for nervous system and retinal development and there is evidence to suggest that DHA deficiencies increase with normal aging . A triple-blind placebo-controlled r and omized repeated- measures trial was conducted with 74 healthy participants , aged 45 - 77 years . Cognitive and visual acuity measures and plasma levels of DHA were determined at baseline and after 90 days of administration of either HiDHA ( ® ) ( Clover Corp. , Sydney , NSW , Australia : 1000 mg of tuna oil ; comprising 252 mg DHA , 60 mg EPA and 10 mg vitamin E ) or placebo ( 100 
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This will increase the generalisability of trial results to the general population .