The selective lipid-lowering effect of vegetarianism on low density lipoproteins in a cross-over experiment. Cardiovascular disease risk factors in free-living men: comparison of two prudent diets, one based on lactoovovegetarianism and the other allowing lean meat. Plasma lipids and lipoproteins in vegetarians and controls. Ambulatory blood pressure and heart rate responses to vegetarian meals BLOOD-PRESSURE-LOWERING EFFECT OF A VEGETARIAN DIET: CONTROLLED TRIAL IN NORMOTENSIVE SUBJECTS Effects of a vegetarian diet and treatment preference on biochemical and dietary variables in overweight and obese adults: a randomized clinical trial. A RANDOMIZED CONTROL TRIAL OF A VEGETARIAN DIET IN THE TREATMENT OF MILD HYPERTENSION Vegetarian diet in the treatment of mild hypertension: a randomized controlled trial. Biochemical and neurohormonal responses to the introduction of a lacto-ovovegetarian diet Serum fatty acid, lipid profile and dietary intake of Hong Kong Chinese omnivores and vegetarians Effectiveness of a low-fat vegetarian diet in altering serum lipids in healthy premenopausal women. Effect of dietary alpha-linolenic acid on thrombotic risk factors in vegetarian men. The influence of maternal vegetarian diet on essential fatty acid status of the newborn. A randomized controlled trial of the effect on blood pressure of dietary non-meat protein versus meat protein in normotensive omnivores. Effects of supplementing n-3 fatty acid enriched eggs and walnuts on cardiovascular disease risk markers in healthy free-living lacto-ovo-vegetarians: a randomized, crossover, free-living intervention study Toward improved management of NIDDM: A randomized, controlled, pilot intervention using a lowfat, vegetarian diet. A low-fat vegan diet and a conventional diabetes diet in the treatment of type 2 diabetes: a randomized, controlled, 74-wk clinical trial.
In a cross-over experiment the effect of  short-term vegetarianism  on serum lipids , lipoproteins and apoproteins was studied . The experimental diet was free of animal products , with the exception of skim milk , and consequently low in saturated fat and cholesterol . Fifteen free-living individuals were r and omly assigned to 3-week periods on either the experimental diet or a control diet which closely approximated the usual intake in the U.S.A. Significant reductions in total cholesterol ( 12.5 % ) , low density lipoprotein cholesterol ( 14.7 % ) , and apo B ( 13.2 % ) were observed , accompanied by a non-significant decrease in high density lipoprotein cholesterol ( 10 % ) , apo A-I ( 3 % ) and a non-significant increase in apo-II ( 4 % ) . These data suggest that a fat-modified diet low in total fat , saturated fat and cholesterol , and moderate ( not high ) in polyunsaturated fat may not lower HDL-C or its apoproteins as much as a diet high in polyunsaturated fat , while having similar effects on LDL-C , and would therefore be preferable as the basis for primary prevention of atherosclerosis In general , vegetarians have lower serum lipids and blood pressures than omnivores have . We tested the blood pressure and serum lipid lowering effects of two fat-modified diets differing primarily in their source of protein . Twenty-six men were r and omized in an incomplete block design to two of three diets : a high-fat diet , a fat-modified lactoovovegetarian diet ( LOV ) and a diet in which 60 % of plant protein in the LOV was replaced with lean meat ( LM ) . Compared with the high-fat diet both prudent diets significantly lowered blood pressure , serum total cholesterol ( TC ) , and LDL cholesterol but significantly increased serum triglycerides . The LOV diet had a significantly greater cholesterol-lowering effect than did the LM diet ( 10 % vs 5 % decrease ) but blood pressure reductions were similar . The partial substitution of lean meat for plant protein in a fat-modified diet did not negate the overall cardiovascular-risk lowering of the lactoovovegetarian diet The possible effect of diet on plasma lipids was investigated in a group of vegetarians . Seventy-three men and 43 women who had adhered to a vegetarian diet for an average of three years were studied in the fasting state and compared with a r and omly selected group of controls matched for age and sex . Mean cholesterol levels in milligrams per deciliter for vegetarians and controls , respectively , were 126 and 184 ; low-density lipoprotein , 73 and 118 ; very-low-density lipoprotein , 11.8 and 17.2 ; high-density lipoproteins , 42 and 49 ; and mean triglyceride levels 59 and 86 . Mean weight and subscapular skinfold thicknesses were 58 kg and 6 mm for vegetarians and 73 kg and 17 mm for controls . Similar differences in lipid levels were found between subgroups of 42 vegetarians and controls with identical mean weights . Multiple regression analyses showed that consumption of dairy foods and eggs , but not body weight , was associated with the lipoprotein and cholesterol findings Objectives : To determine the effects of a vegetarian diet on daytime ambulatory ( Accutracker ) blood pressures and heart rates , and to relate these to the estimated peak in plasma glucose to determine whether low-glycaemic-index diets reduce sympathetic activity in response to differences in postpr and ial glucose and insulin . Design : The subjects were matched for age and body mass index and r and omly assigned to one of two parallel diet groups . Setting : Clinical . Participants : Twenty-one normotensive non-vegetarian male hospital workers volunteered for the study and 20 completed it . Intervention : After 2 weeks of baseline measurement the subjects followed an omnivorous or a lacto-ovovegetarian diet for 6 weeks . Main outcome measures : Daytime ambulatory blood pressures and heart rate , and postbreakfast catecholamines , insulin and glucose . Results : Ambulatory systolic blood pressure and heart rates were lower in the vegetarian group during the working day . The prepr and ial rise in diastolic pressure was attenuated on the vegetarian diet . There were no differences in plasma catecholamine , glucose or insulin levels sample d after breakfast on the two dietary regimes . Conclusions : The blood pressure-lowering effect of a lacto-ovovegetarian diet , which occurs throughout the working day , is associated with lower heart rates , suggesting a central nervous or cardiac mechanism . The possibility that the lower glycaemic index of a lacto-ovovegetarian diet has some effect needs to be investigated further in relation to major meal-times and studied in both normotensive and hypertensive subjects 59 healthy , omnivorous subjects aged 25 - 63 years were r and omly allocated to a control group , which ate an omnivorous diet for 14 weeks , or to one of two experimental groups , whose members ate an omnivorous diet for the first 2 weeks and a lacto-ovo-vegetarian diet for one of two 6-week experimental periods .  Mean systolic and diastolic blood pressures did not change in the control group but fell significantly in both experimental groups during the vegetarian diet and rose significantly in the experimental group which reverted to the omnivorous diet . Adjustment of the blood-pressure changes for age , obesity , heart rate , weight change , and blood pressure before dietary change indicated a diet-related fall of some 5 - 6 mm Hg systolic and 2 - 3 mm Hg diastolic . Although the nutrient(s ) causing these blood-pressure changes are unknown , the effects were apparently not mediated by changes in sodium or potassium intake BACKGROUND A vegetarian diet may lead to numerous health benefits , including weight loss . OBJECTIVE We examined the joint effects of personal preference of dietary treatment and a calorie-restricted , low-fat lactoovovegetarian diet ( LOV-D ) compared with a st and ard calorie-restricted , low-fat omnivorous diet ( STD-D ) on changes in weight , total cholesterol , ratio of LDL to HDL cholesterol ( LDL : HDL cholesterol ) , triacylglycerols , insulin resistance , and macronutrient intake during an 18-mo study . DESIGN This was a r and omized clinical trial of 176 overweight and obese adults who were recruited and r and omly assigned first to 1 of 2 preference conditions ( yes or no ) . If assigned to Preference-No , they were r and omly assigned to 1 of the 2 diet conditions ( STD-D or LOV-D ) . If assigned to Preference-Yes , they were assigned to the diet they indicated as preferred at screening . The 12-mo intervention was followed by a 6-mo maintenance phase . RESULTS Participants were mainly women ( 86.9 % ) and white ( 70.5 % ) ; 75 % completed the 18-mo study . A significant interaction between preference and dietary treatment was not observed for any of the outcome variables . However , participants in the Preference-No groups significantly decreased their triacylglycerols ( P = 0.04 ) . The only effect observed for diet was a borderline significant decrease in LDL : HDL cholesterol for the LOV-D group ( P = 0.06 ) . Within the LOV-D groups , those who were 100 % adherent to the LOV-D had significant and marginally significant reductions in monounsaturated fat ( P = 0.02 ) and total fat ( P = 0.05 ) intakes at 18 mo . CONCLUSIONS Our findings suggest that neither prescribing a vegetarian diet nor allowing persons to choose their preferred diet had a significant effect on outcome measures . However , all participants had a significant reduction in total energy and fat intakes and an increase in energy expenditure , which was reflected in reduced body weight . This clinical trial was registered at www . clinical trials.gov as NCT00330629 1 . The effect of an ovo‐lacto‐vegetarian ( OLV ) diet on blood pressure was assessed in a r and omized , controlled , crossover trial in 58 mild untreated hypertensive subjects recruited from the Perth Centre for the 1983 NHF Risk Factor Prevalence Survey The effect on blood pressure of an ovo-lacto-vegetarian ( OLV ) diet was assessed in a r and omized controlled crossover trial . Fifty-eight mild untreated hypertensive subjects recruited from the Perth Centre for the 1983 National Heart Foundation ( NHF ) Risk Factor Prevalence Survey were r and omly allocated to one of three groups : the first maintained their usual diet throughout 12 weeks ; the other two were given an OLV diet for either the first or second 6 weeks of the 12-week trial . A significant fall in systolic blood pressure , on average of the order of 5 mmHg , was associated with eating an OLV diet .  Blood pressure change was unrelated to change in urinary sodium , potassium or body weight , but was related to initial blood pressures . Although an OLV diet may have an adjunctive role in control of mild hypertension , in view of likely problems with acceptability the dietary components responsible for the blood pressure changes need to be identified Objective : To assess the mechanisms of the blood pressure-lowering effect of a vegetarian diet in the early and later stages of dietary intervention Design : After 2 weeks without intervention ( baseline ) , 20 normotensive men were matched for age and body mass index and r and omly allocated to an omnivorous ( control ) or a lacto-ovovegetarian diet for 6 weeks in a parallel trial Methods : Ambulatory blood pressures were recorded between 0800 and 1700 h on alternate days during the first week of intervention , twice in the second week and weekly thereafter . Blood sample s collected after a st and ard breakfast were analysed for plasma noradrenaline , adrenaline , atrial natriuretic peptide ( ANP ) , renin , aldosterone , glucose and insulin . Factor and multiple regression analyses were used to assess the association among neurohormonal factors , blood pressures and diet . Results were analysed for the first week of the diet and for the entire 6 weeks Results : Ambulatory blood pressures at work were lower on the vegetarian diet than in the controls . This blood pressure decrease was associated with a factor representing lower plasma catecholamine and renin activity levels throughout the study , and a factor representing reduced plasma glucose and insulin levels in week 1 of intervention only . Plasma ANP levels were significantly higher during week 1 of the vegetarian diet Conclusions : A blood pressure lowering effect of a vegetarian diet during normal working activity was shown . Using factors derived from the biochemical variables , results were in keeping with the hypothesis that these effects may be mediated by reduced sympatho-adrenal activity consequent to altered glucose and insulin h and ling . An early increase in plasma ANP may contribute to the blood pressure Objective : To examine the serum fatty acid and lipid profiles and dietary intake of  Hong Kong Chinese omnivores and vegetarians  with respect to cardiovascular health . Design : R and om population survey stratified by age and sex . Subjects : One-hundred and ninety-four omnivore subjects ( 81 men , 113 women ) age 25–70 y , and 60 ovo-lacto-vegetarian adults ( 15 men , 45 women ) age 30–55 y. Measurements : Nutrient quantitation was by a food frequency method . Serum fatty acids were analysed by  gas chromatography , and serum lipid  by st and ard laboratory methods . Results : Compared with omnivores , vegetarians had higher serum concentrations of polyunsaturated ( PUFA ) and monosaturated fatty acids ( MUFA ) , and lower saturated fatty acids ( SFA ) , long chain omega-3 and trans fatty acids ( TFA ) . They also had lower serum cholesterol and higher apoA-I concentrations , but the LDL/HDL ratio was not different . The ratio of polyunsaturated to saturated fatty acids intake was higher in vegetarians . Compared with results from population s with higher incidences of coronary heart disease , while lower myristic and palmitic acid concentrations and higher eicosapentaneoic ( EPA ) and docosahexanoic acid ( DHA ) may partly account for the difference in incidence , linoleic acid concentration was higher . Although the Chinese vegetarian diet may be beneficial for heart health in that antioxidant and fibre intakes are higher and saturated fat lower , the low EPA and DHA due to omission from dietary source and suppressed formation by high linoleic acid level , and the presence of TFA in the diet , may exert an opposite effect . Conclusion : There are some favourable features in the serum fatty acid profile in the Hong Kong Chinese population with respect to cardiovascular health , but the consumption of TFA is of concern . The Chinese vegetarian diet also contains some adverse features . Sponsorship : This study is partly sponsored by the Hong Kong Health Services Research Grant . European Journal Of Clinical Nutrition ( 2000 ) 24 , Few controlled trials have studied cholesterol-lowering diets in premenopausal women . None has examined the cholesterol-lowering effect of a low-fat vegetarian diet , which , in other population groups , leads to marked reductions in serum cholesterol concentrations and , in combination with other life-style changes , a regression of atherosclerosis . We tested the hypothesis that a low-fat , vegetarian diet significantly reduces serum total and low-density lipoprotein ( LDL ) cholesterol concentrations in premenopausal women . In a crossover design , 35 women , aged 22 to 48 , followed a low-fat vegetarian diet deriving approximately 10 % of energy from fat for 2 menstrual cycles . For 2 additional cycles , they followed their customary diet while also taking a " supplement " ( placebo ) pill .  Serum lipid concentrations were assessed at baseline and during each intervention phase . Mean serum LDL , high-density lipoprotein ( HDL ) , and total cholesterol concentrations decreased 16 . 9 % , 16.5 % , and 13.2 % , respectively , from baseline to the intervention diet phase ( p<0.001 ) , whereas mean serum triacylglycerol concentration increased 18.7 % ( p<0.01 ) . LDL/HDL ratio remained unchanged . Thus , in healthy premenopausal women , a low-fat vegetarian diet led to rapid and sizable reductions in serum total , LDL , and HDL cholesterol concentrations BACKGROUND Vegetarians have lower platelet and plasma concentrations of n-3 polyunsaturated fatty acids ( PUFAs ) than do omnivores . We recently showed that male vegetarians have higher platelet aggregability than do omnivores . OBJECTIVE We investigated whether male vegetarians ( n = 17 ) who consumed an increased amount of dietary alpha-linolenic acid ( ALA )  showed any changes in their tissue profile of PUFAs , plasma thromboxane concentrations , platelet aggregability , or hemostatic factors . DESIGN During the study , all subjects maintained their habitual vegetarian diets except that a proportion of dietary fat was replaced with vegetable oils and margarines that were provided . Initially , all subjects consumed a low-ALA diet ( containing safflower oil and safflower oil-based margarine ) for 14 d ; they then consumed either a moderate-ALA diet ( containing canola oil and canola oil-based margarine ) or a high-ALA diet ( containing linseed oil and linseed oil-based margarine ) for 28 d. Blood sample s were collected at day 0 ( baseline ) , day 14 , and day 42 . RESULTS Eicosapentaenoic acid , docosapentaenoic acid , total n-3 PUFAs , and the ratio of n-3 to n-6 PUFAs were significantly increased ( P < 0.05 ) , whereas the ratio of arachidonic acid to eicosapentaenoic acid was decreased ( P < 0.05 ) , in platelet phospholipids , plasma phospholipids , and triacylglycerols after either the moderate-ALA or high-ALA diet compared with the low-ALA diet . No significant differences were observed in thrombotic risk factors . CONCLUSION ALA from vegetable oils ( canola and linseed ) has a beneficial effect on n-3 PUFA concentrations of platelet phospholipids and plasma lipids in vegetarian males OBJECTIVES To evaluate whether a  maternal vegetarian diet influences the essential fatty acid status of the newborn and whether this is related to outcome of pregnancy . DESIGN  Dietary intake  and the fatty acid composition of plasma phospholipids were determined in 24 South Asian vegetarian and 24 white omnivore non-pregnant premenopausal women r and omly selected from the general population of North London . Umbilical cords and cord blood were collected at delivery from 48 South Asian vegetarian women and 98 white omnivores from the same catchment area along with details of antenatal history and the outcome of pregnancy . The fatty acid composition of the cord arteries and that of cord plasma phospholipids were analysed in a subset of 32 pairs of subjects , who were matched for maternal age , gestational age , parity and sex of infant . RESULTS Intakes of linoleic acid  ( 18:2n-6 ) expressed as proportion of the dietary energy and the ratio of linoleic to alpha-linolenic acid ( 18:3n-3 ) were higher in the vegetarian women , and eicosapentaenoic acid ( EPA , 20:5n-3 ) and docosahexaenoic acid ( DHA , 22:6n-3 ) were absent from their diets . The proportion of linoleic acid , as well as the absolute concentration , was greater and those of EPA and DHA were lower in plasma phospholipids , plasma free fatty acid and total plasma lipids of the vegetarians compared with the white subjects . The proportion of DHA was lower ( P > 0.001 ) but that of docosapentaenoic acid ( 22:5n-6 ) was greater ( P < 0.001 ) in cord those from the omnivores . The ratio of 20:3n-9/20:4n-6 was elevated in cord artery but not in cord plasma phospholipids in both groups . Early onset of labour and the duration of gestation was 5.6 days shorter . Birth weight , head circumference and length were lower in the infants born to South Asian vegetarians even after adjusting for maternal height , duration of gestation , parity , gender of infants and smoking habits . Multivariate analysis did not reveal any relationship between the proportions of DHA in plasma or cord artery phospholipids and the birthweight or head circumference of the infants . CONCLUSION This study demonstrates that vegetarians give birth to infants with less DHA in their plasma and cord artery phospholipids but this did not appear to be independently related to the outcome of pregnancy 1 . A r and omized , controlled trial was carried out to examine whether changes in type and amount of dietary protein were responsible for earlier observations of blood-pressure-lowering effects of lacto-ovo-vegetarian diets . 2 . Sixty-four subjects were pair-matched for sex , age , weight and sitting systolic blood pressure , and were r and omly allocated to receive one of two types of protein supplement : one containing proteins from meat , the other proteins from non-meat sources . The supplements were balanced in terms of other nutrients . Consumption of other meat , poultry or fish was prohibited . 3 . Sitting and st and ing blood pressures , weight , dietary intakes and plasma and urinary electrolytes were measured at regular intervals during the 12 weeks of trial . Urinary 3-methylhistidine was used as a measure of compliance . 4 . Fifty subjects completed the trial . There were no statistically significant blood pressure differences between groups either at baseline or at end-of-trial , neither were there any substantive differences in mean blood pressure changes between baseline and end-of-trial . 3-Methyl-histidine excretion was significantly lower in subjects on the non-meat diet . 5 . The results suggest that the protein components of the lacto-ovo-vegetarian diet are not responsible for the blood-pressure-lowering effects of that diet Background Plant and marine n-3 fatty acids ( FA ) may favorably modify select markers of cardiovascular disease risk . Whether supplementing the habitual diet of lacto-ovo-vegetarians ( LOV ) with walnuts ( containing α-linolenic acid , ALA ) and n-3 FA enriched eggs ( containing primarily docosahexaenoic acid , DHA and ALA ) would have equivalent effects on CVD risk factors is explored in this study . Methods In this study , 20 healthy free-living LOVs following their habitual diet were r and omly assigned in a crossover design to receive one of three supplements : n-3 FA enriched egg ( 6/week ) , walnuts ( 28.4 g , 6/week ) or a st and ard egg , 6/week ( control ) for 8 weeks each with 4-wk washout between treatments . Erythrocyte membrane fatty acids , serum lipids and inflammatory markers were measured at the end of each treatment . Results Dietary compliance was observed by an expected increase in erythrocyte membrane ALA following the walnut treatment and in DHA following the n-3 FA enriched egg treatment . Walnut treatment lowered serum triacylglycerol , total cholesterol and Apo B ( p < 0.05 ) compared to the st and ard egg but not the n-3 FA enriched egg treatment . However , walnut treatment significantly reduced total : HDL cholesterol ratio compared to both egg treatments . There were no differences between treatments for any of the inflammatory markers . Conclusions For LOV , a direct source of DHA such as n-3 FA enriched eggs seems necessary to increase membrane levels of DHA . However for producing an overall favorable blood lipid profile , daily consumption of a h and ful of walnuts rich in ALA may be a preferred option for lacto-ovo vegetarian OBJECTIVE To investigate whether glycemic and lipid control in patients with non-insulin-dependent diabetes ( NIDDM ) can be significantly improved using a low-fat , vegetarian ( vegan ) diet in the absence of recommendations regarding exercise or other lifestyle changes . METHODS Eleven subjects with NIDDM recruited from the Georgetown University Medical Center or the local community were r and omly assigned to a low-fat vegan diet ( seven subjects ) or a conventional low-fat diet ( four subjects ) . Two additional subjects assigned to the control group failed to complete the study . The diets were not design ed to be isocaloric . Fasting serum glucose , body weight , medication use , and blood pressure were assessed at baseline and biweekly thereafter for 12 weeks . Serum lipids , glycosylated hemoglobin , urinary albumin , and dietary macronutrients were assessed at baseline and 12 weeks . RESULTS Although the sample was intentionally small in accordance with the pilot study design , the 28 % mean reduction in fasting serum glucose of the experimental group , from 10.7 to 7.75 mmol/L ( 195 to 141 mg/dl ) , was significantly greater than the 12 % decrease , from 9.86 to 8.64 mmol/L ( 179 to 157 mg/dl ) , for the control group ( P < 0.05 ) . The mean weight loss was 7.2 kg in the experimental group , compared to 3 . 8 kg for the control group ( P < 0.005 ) . Of six experimental group subjects on oral hypoglycemic agents , medication use was discontinued in one and reduced in three . Insulin was reduced in both experimental group patients on insulin . No patient in the control group reduced medication use . Differences between the diet groups in the reductions of serum cholesterol and 24-h microalbuminuria did not reach statistical significance ; however , high-density lipoprotein concentration fell more sharply ( 0.20 mmol/L ) in the experimental group than in the control group ( 0.02 mmol/L ) ( P < 0.05 ) . CONCLUSION The use of a low-fat , vegetarian diet in patients with NIDDM was associated with significant reductions in fasting serum glucose concentration and body weight in the absence of recommendations for exercise . A larger study is needed for confirmation BACKGROUND Low-fat vegetarian and vegan diets are associated with weight loss , increased insulin sensitivity , and improved cardiovascular health . OBJECTIVE We compared the effects of a low-fat vegan diet and conventional diabetes diet recommendations on glycemia , weight , and plasma lipids . DESIGN Free-living individuals with type 2 diabetes were r and omly assigned to a low-fat vegan diet ( n = 49 ) or a diet following 2003 American Diabetes Association guidelines ( conventional , n = 50 ) for 74 wk . Glycated hemoglobin ( Hb A(1c ) ) and plasma lipids were assessed at weeks 0 , 11 , 22 , 35 , 48 , 61 , and 74 . Weight was measured at weeks 0 , 22 , and 74 . RESULTS Weight loss was significant within each diet group but not significantly different between groups ( -4.4 kg in the vegan group and -3.0 kg in the conventional diet group , P = 0.25 ) and related significantly to Hb A(1c ) changes ( r = 0.50 , P = 0.001 ) . Hb A(1c ) changes from baseline to 74 wk or last available values were -0.34 and -0.14 for vegan and conventional diets , respectively ( P = 0.43 ) . Hb A(1c ) changes from baseline to last available value or last value before any medication adjustment were -0.40 and 0.01 for vegan and conventional diets , respectively ( P = 0.03 ) . In analyses before alterations in lipid-lowering medications , total cholesterol decreased by 20.4 and 6.8 mg/dL in the vegan and conventional diet groups , respectively ( P = 0.01 ) ; LDL cholesterol decreased by 13.5 and 3.4 mg/dL in the vegan and conventional groups , respectively ( P = 0.03 ) . CONCLUSIONS Both diets were associated with sustained reductions in weight and plasma lipid concentrations . In an analysis controlling for medication changes , a low-fat vegan diet appeared to improve glycemia and plasma lipids more than did conventional diabetes diet recommendations . Whether the observed differences provide clinical benefit for the macro- or microvascular complications of diabetes remains to be established . This trial was registered at clinical trials.gov as NCT00276939
Conclusions This systematic review and meta‐ analysis provides evidence that vegetarian diets effectively lower blood concentrations of total cholesterol , low‐density lipoprotein cholesterol , high‐density lipoprotein cholesterol , and non – high‐density lipoprotein cholesterol .
Such diets could be a useful nonpharmaceutical means of managing dyslipidemia , especially hypercholesterolemia
Background Vegetarian diets exclude all animal flesh and are being widely adopted by an increasing number of people ; however , effects on blood lipid concentrations remain unclear .
This meta‐ analysis aim ed to quantitatively assess the overall effects of  vegetarian diets on blood lipids .