Cheese and Cardiovascular Disease Risk: A Review of the Evidence and Discussion of Possible Mechanisms.

Currently, the effect of dairy products on cardiovascular risk is a topic much debated and with conflicting results. The purpose of this review is to give an overview of the existing literature regarding the effect of cheese intake and risk of cardiovascular disease (CVD). Studies included reporting the intake of cheese and risk of CVD or risk markers of CVD represent four human intervention studies, nine prospective studies, one prospective case-cohort study, one prospective nested case-control study, five case-control studies, five cross-sectional studies and three correlation studies. The possible mechanisms that may be of importance include calcium, protein, fermentation and the fatty acid composition of cheese. Results from four prospective studies reported no association between cheese intake and CVD risk, whereas one reported an increased risk, two reported a decreased risk and one reported no association in men but a decreased risk in women. In addition, results from four intervention studies indicated no harmful effect on cholesterol concentrations when comparing fat intake from cheese with fat from butter. The underlying mechanisms for these findings still need to be elucidated.

Cheddar Cheese Ripening Affects Plasma Nonesterified Fatty Acid and Serum Insulin Concentrations in Growing Pigs.

BACKGROUND: Meta-analyses of observational studies found cheese consumption to be inversely associated with risk of type 2 diabetes and metabolic syndrome. This may be attributed to the bioactive compounds produced during cheese ripening. OBJECTIVE: The objective of this study was to investigate by means of a porcine model how cheeses with different ripening times affect blood glucose, insulin, and lipid concentrations and fecal-fat excretion. METHODS: A parallel-arm randomized intervention study with 36 Landrace × Yorkshire × Duroc crossbred 3-mo-old female pigs was conducted. The pigs were fed a 21-d butter-rich run-in diet (143 g of butter/kg diet), followed by a 14-d intervention with 1 of 3 isocaloric diets: 4-mo ripened cheddar (4-MRC) diet, 14-mo ripened cheddar (14-MRC) diet, or 24-mo ripened cheddar (24-MRC) diet (350 g of cheese/kg diet). Serum cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, and insulin; plasma nonesterified fatty acids (NEFAs) and glucose; fecal-fat excretion; and body weight were measured. RESULTS: Plasma NEFAs were lower in the 24-MRC (201 ± 26 µEq/L) and in the 14-MRC (171 ± 19 µEq/L) diet groups than in the 4-MRC diet group (260 ± 27 µEq/L; P = 0.044 and P = 0.001). Serum insulin was lower in the 24-MRC diet group (1.04 ± 0.09 mmol/L) than in the 4-MRC diet group (1.44 ± 0.14 mmol/L; P = 0.002), but intermediate and not different from either in the 14-MRC diet group (1.25 ± 0.11 mmol/L). Likewise, homeostasis model assessment of insulin resistance was lower in the 24-MRC diet group (0.030 ± 0.003) than in the 4-MRC diet group (0.041 ± 0.005; P < 0.01), but intermediate and not different from either in the 14-MRC group (0.036 ± 0.004). CONCLUSIONS: Intake of long-term ripened cheddar improved indicators of insulin sensitivity in growing pigs compared with short-term ripened cheddar. This may also be important for human health.

Effects of butter from mountain-pasture grazing cows on risk markers of the metabolic syndrome compared with conventional Danish butter: a randomized controlled study.

BACKGROUND: There is considerable interest in dairy products from low-input systems, such as mountain-pasture grazing cows, because these products are believed to be healthier than products from high-input conventional systems. This may be due to a higher content of bioactive components, such as phytanic acid, a PPAR-agonist derived from chlorophyll. However, the effects of such products on human health have been poorly investigated. OBJECTIVE: To compare the effect of milk-fat from mountain-pasture grazing cows (G) and conventionally fed cows (C) on risk markers of the metabolic syndrome. DESIGN: In a double-blind, randomized, 12-week, parallel intervention study, 38 healthy subjects replaced part of their habitual dietary fat intake with 39 g fat from test butter made from milk from mountain-pasture grazing cows or from cows fed conventional winter fodder. Glucose-tolerance and circulating risk markers were analysed before and after the intervention. RESULTS: No differences in blood lipids, lipoproteins, hsCRP, insulin, glucose or glucose-tolerance were observed. Interestingly, strong correlations between phytanic acid at baseline and total (P<0.0001) and LDL cholesterol (P=0.0001) were observed. CONCLUSIONS: Lack of effects on blood lipids and inflammation indicates that dairy products from mountain-pasture grazing cows are not healthier than products from high-input conventional systems. Considering the strong correlation between LDL cholesterol and phytanic acid at baseline, it may be suggested that phytanic acid increases total and LDL cholesterol. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01343589.

Effect of dairy fat on plasma phytanic acid in healthy volunteers - a randomized controlled study.

BACKGROUND: Phytanic acid produced in ruminants from chlorophyll may have preventive effects on the metabolic syndrome, partly due to its reported RXR and PPAR- α agonist activity. Milk from cows fed increased levels of green plant material, contains increased phytanic acid concentrations, but it is unknown to what extent minor increases in phytanic acid content in dairy fat leads to higher circulating levels of phytanic acid in plasma of the consumers. OBJECTIVE: To investigate if cow feeding regimes affects concentration of plasma phytanic acid and risk markers of the metabolic syndrome in human. DESIGN: In a double-blind, randomized, 4 wk, parallel intervention study 14 healthy young subjects were given 45 g milk fat/d from test butter and cheese with 0.24 wt% phytanic acid or a control diet with 0.13 wt% phytanic acid. Difference in phytanic acid was obtained by feeding roughage with low or high content of chlorophyll. RESULTS: There tended to be a difference in plasma phytanic acid (P = 0.0730) concentration after the dietary intervention. Plasma phytanic acid increased significantly within both groups with the highest increase in control group (24%) compared to phytanic acid group (15%). There were no significant effects of phytanic acid on risk markers for the metabolic syndrome. CONCLUSIONS: The results indicate that increased intake of dairy fat modify the plasma phytanic acid concentration, regardless of cows feeding regime and the minor difference in dietary phytanic acid. Whether the phytanic acid has potential to affects the risk markers of the metabolic syndrome in human still remain to be elucidated.

Acute ingestion of long-chain (n-3) polyunsaturated fatty acids decreases fibrinolysis in men with metabolic syndrome.

Individuals with metabolic syndrome (MetS) often have elevated plasma plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (t-PA), contributing to an increased risk of cardiovascular disease. PAI-1 and t-PA may be affected by chronic (n-3) long-chain PUFA [(n-3)LCPUFA] supplementation; however, the acute impact of fat ingestion on these risk factors has not been established. Our objective was to investigate the acute effect of (n-3)LCPUFA on plasma PAI-1, t-PA, and platelet aggregation. We conducted a randomized crossover study in which men (n = 8, > or =45 y) with MetS consumed water or a high-saturated fat beverage (1 g fat/kg body weight) with either a high or low content of (n-3)LCPUFA. Blood samples were collected over 8 h to measure triacylglycerol (TAG), PAI-1, t-PA, and platelet aggregation. Both fat loads resulted in a significant increase in whole blood TAG concentration, plasma PAI-1 and t-PA concentrations, and PAI-1 activity, as well as a significant decrease in t-PA activity during the postprandial period. Interestingly, PAI-1 concentration and activity increased more following the high (n-3)LCPUFA compared with the low (n-3)LCPUFA beverage (P < 0.05). Furthermore, the high (n-3)LCPUFA beverage resulted in a lower t-PA activity (P < 0.05), whereas the effects of the 2 fat loads on the plasma t-PA concentration and platelet aggregation did not differ. Overall, acute intake of a high (n-3)LCPUFA beverage shifted the balance between plasma PAI-1 and t-PA, which might indicate a lower capacity for fibrinolysis.

Correction: Effect of high milk and sugar-sweetened and noncaloric soft drink intake on insulin sensitivity after 6 months in overweight and obese adults: a randomized controlled trial.

Since publication the authors noticed an error in Tables 2, 3, and 4 of the original article, where the pre-intervention values were presented by mean and SD instead of mean and SE as described in the table text. The correct tables are reproduced below where SD's are replaced by SE's.

Conjugated linoleic acids reduce body fat in healthy postmenopausal women.

Isomers of conjugated linoleic acids (CLA) reduce fat mass (FM) and increase insulin sensitivity in some, but not all, murine studies. In humans, this effect is still debatable. In this study, we compared the effect of 2 CLA supplements on total and regional FM assessed by dual energy X-ray absorptiometry, changes in serum insulin and glucose concentrations, and adipose tissue (AT) gene expression in humans. In a double-blind, parallel, 16-wk intervention, we randomized 81 healthy postmenopausal women to 1) 5.5 g/d of 40/40% of cis9,trans11-CLA (c9,t11-CLA) and trans10,cis12-CLA (t10,c12-CLA) (CLA-mix); 2) cis9, trans11-CLA (c9,t11-CLA); or 3) control (olive oil). We assessed all variables before and after the intervention. The CLA-mix group had less total FM (4%) and lower-body FM (7%) than the control (P = 0.02 and < 0.001, respectively). Post hoc analyses showed that serum insulin concentrations were greater in the CLA-mix group (34%) than the control group (P = 0.02) in the highest waist circumference tertile only. AT mRNA expression of glucose transporter 4, leptin, and lipoprotein lipase was lower, whereas expression of tumor necrosis factor-alpha was higher in the CLA-mix group than in the control group (P < 0.04). In conclusion, a 50:50 mixture of c9,t11- and t10,c12-CLA isomers resulted in less total and lower-body FM in postmenopausal women and greater serum insulin concentrations in the highest waist circumference tertile. Future research is needed to confirm the insulin desensitizing effect of the CLA mixture and the effect on the mRNA expression of adipocyte-specific genes in humans.

A low-glycemic-index diet reduces plasma plasminogen activator inhibitor-1 activity, but not tissue inhibitor of proteinases-1 or plasminogen activator inhibitor-1 protein, in overweight women.

BACKGROUND: The development of obesity has been suggested to involve plasminogen activator inhibitor-1 (PAI-1) and tissue inhibitor of proteinases-1 (TIMP-1). Plasma PAI-1 is elevated in obesity. A low-glycemic-index (LGI) diet may have a beneficial effect on obesity through a decrease in plasma PAI-1, but whether it affects plasma TIMP-1 in healthy humans has not been studied. OBJECTIVE: We investigated whether a 10-wk intake of an LGI or a high-glycemic-index (HGI), high-carbohydrate, low-fat, ad libitum diet is associated with decreases in plasma PAI-1 and TIMP-1 concentrations in overweight women. DESIGN: Forty-four overweight women [body mass index (BMI; in kg/m2): 27.5+/-0.23] were randomly assigned to consume an HGI or an LGI diet for 10 wk. A subgroup of 29 women was assigned to participate in an additional 4-h meal test on the last day of the 10-wk intervention. RESULTS: PAI-1 activity decreased after 10 wk of the LGI diet and was significantly different between groups. Changes in PAI-1 antigen followed the same trend, but no significant difference was observed between groups. No difference in plasma TIMP-1 concentrations was observed between groups. PAI-1 and TIMP-1 concentrations after the 4-h meal test were not significantly different between groups. CONCLUSION: An LGI diet reduces fasting plasma PAI-1 activity and therefore may be useful for diminishing the adverse cardiovascular effects of obesity. This trial was registered at clinicaltrials.gov as NCT00324090.

An oil mixture with trans-10, cis-12 conjugated linoleic acid increases markers of inflammation and in vivo lipid peroxidation compared with cis-9, trans-11 conjugated linoleic acid in postmenopausal women.

A mixture of trans-10, cis-12 (t10,c12) and cis-9, trans-11 (c9,t11) conjugated linoleic acid (CLA mixture) reduced atherosclerosis in animals, thus the effect of these isomers on endothelial dysfunctions leading to inflammation and atherosclerosis is of interest. We gave 75 healthy postmenopausal women a daily supplement of 5.5 g of oil rich in either CLA mixture, an oil rich in the naturally occurring c9,t11 CLA (CLA milk), respectively, or olive oil for 16 wk in a double-blind, randomized, parallel intervention study. We sampled blood and urine before and after the intervention. The ratios of total cholesterol:HDL cholesterol and concentrations of C-reactive protein, fibrinogen, and plasminogen activator inhibitor-1 were significantly higher in women supplemented with the CLA mixture than in those supplemented with CLA milk. Plasma triacylglycerol was significantly higher and HDL cholesterol was lower in women supplemented with the CLA mixture than with olive oil. Both CLA supplements increased lipid peroxidation, a marker of in vivo oxidative stress measured as urinary free 8-iso-prostaglandin F(2alpha). However, the CLA mixture increased lipid peroxidation more than the CLA milk did. The plasma cytokines interleukin-6 and tumor necrosis factor-alpha were not affected by the treatments, nor were any of the other variables measured. In conclusion, oil containing trans-10,cis-12 CLA has several adverse effects on classical and novel markers of coronary vascular disease, whereas the c9,t11 CLA isomer is more neutral, except for a small but significant increase in lipid peroxidation compared with olive oil.

A diet rich in conjugated linoleic acid and butter increases lipid peroxidation but does not affect atherosclerotic, inflammatory, or diabetic risk markers in healthy young men.

Intake of conjugated linoleic acid (CLA) has been demonstrated to beneficially affect risk markers of atherosclerosis and diabetes in rats. CLA is naturally found in milk fat, especially from cows fed a diet high in oleic acid, and increased CLA intake can occur concomitantly with increased milk fat intake. Our objective was to investigate the effect of CLA as part of a diet rich in butter as a source of milk fat on risk markers of atherosclerosis, inflammation, diabetes type II, and lipid peroxidation. A total of 38 healthy young men were given a diet with 115 g/d of CLA-rich fat (5.5 g/d CLA oil, a mixture of 39.4% cis9, trans11 and 38.5% trans10, cis12) or of control fat with a low content of CLA in a 5-wk double-blind, randomized, parallel intervention study. We collected blood and urine before and after the intervention. The fatty acid composition of plasma triacylglycerol, cholesterol esters, and phospholipids reflected that of the intervention diets. The CLA diet resulted in increased lipid peroxidation measured as an 83% higher 8-iso-prostaglandin F2alpha concentration compared with the control, P < 0.0001. We observed no other significant differences in the effect of the interventions diets. In conclusion, when given as part of a diet rich in butter, a mixture of CLA isomers increased lipid peroxidation but did not affect risk markers of cardiovascular disease, inflammation, or fasting insulin and glucose concentrations.

Effect of whole milk compared with skimmed milk on fasting blood lipids in healthy adults: a 3-week randomized crossover study.

BACKGROUND/OBJECTIVES: Dietary guidelines have for decades recommended choosing low-fat dairy products due to the high content of saturated fat in dairy known to increase blood concentration of LDL cholesterol. However, meta-analyses including observational studies show no association between overall dairy intake and risk of cardiovascular disease and even point to an inverse association with type 2 diabetes. The objective was to compare the effects of whole milk (3.5% fat) with skimmed milk (0.1% fat) on fasting serum blood lipids, insulin, and plasma glucose in healthy subjects. SUBJECT/METHODS: A randomized, controlled 2 × 3-week crossover dietary intervention in 18 healthy adults randomly assigned to a sequence of treatments consisting of 0.5 L/d of whole milk and skimmed milk as part of their habitual diet. A total of 17 subjects completed the intervention. RESULTS: Whole milk increased HDL cholesterol concentrations significantly compared to skimmed milk (P < 0.05). There were no significant differences between whole milk and skimmed milk in effects on total and LDL cholesterol, triacylglycerol, insulin, and glucose concentrations. CONCLUSIONS: Intake of 0.5 L/d of whole milk did not adversely affect fasting blood lipids, glucose, or insulin compared to skimmed milk. Moreover, intake of whole milk increased HDL cholesterol concentration compared to skimmed milk. These findings suggest that if the higher energy content is taken into account, whole milk might be considered a part of a healthy diet among the normocholesterolemic population.

Effect of high milk and sugar-sweetened and non-caloric soft drink intake on insulin sensitivity after 6 months in overweight and obese adults: a randomized controlled trial.

BACKGROUND/OBJECTIVES: Milk contributes with saturated fat, but randomized controlled trials (RCT) on the effects of dairy on the risk of type 2 diabetes (T2D) where dairy is given as whole foods are scarce. The objective of our study was to investigate the long-term effects of semi-skimmed milk on insulin sensitivity and further to compare milk with sugar-sweetened soft drinks (SSSD). SUBJECTS/METHODS: A secondary analysis of a 6-month RCT with 60 overweight and obese subjects randomly assigned to 1 L/d of either milk (1.5 g fat/100 mL), SSSD, non-calorie soft drink (NCSD), or water was conducted. Insulin sensitivity was evaluated by oral glucose tolerance test (OGTT) and plasma free fatty acids. Second, fasting blood lipids, blood pressure, and concentration of plasminogen activator inhibitor-1 were assessed. RESULTS: There were no differences between milk, SSSD, NCSD, and water on insulin sensitivity assessed by OGTT (Matsuda Index, fasting, and area under the curve glucose, insulin and homeostasis model assessment values). SSSD increased total cholesterol compared to NCSD (P = 0.007), and triacylglycerol compared to NCSD and water (P = 0.045 and 0.045, respectively). None of the other parameters differed significantly between the groups. CONCLUSIONS: In conclusion, there were no differences in effect between intake of milk, SSSD, NCSD, and water (1 L/d) for 6-month on risk markers of T2D in overweight and obese adults. As a secondary analysis, these results need confirmation in future studies.

Consumption of regular-fat vs reduced-fat cheese reveals gender-specific changes in LDL particle size - a randomized controlled trial.

BACKGROUND: Regular-fat cheese does not seem to increase low density lipoprotein cholesterol (LDL-C) concentrations compared to reduced-fat cheese. However, plasma LDL-C concentrations do not reflect levels and size of LDL particles, which might be a better predictor of cardiovascular risk. METHODS: The aim was to compare the effects of regular-fat cheese vs reduced-fat cheese and carbohydrate-rich foods on LDL particle size distribution in adults with ≥ 2 metabolic syndrome (MetS) risk factors. The study was part of a 12 weeks' randomized controlled trial in which subjects had been randomly allocated to 1 of 3 intervention groups; regular-fat cheese (REG), reduced-fat cheese (RED) or a no-cheese/carbohydrate (CHO) group. Subjects in the REG and RED groups consumed 80 g cheese/d per 10 MJ, whereas subjects in the CHO consumed bread and jam corresponding to 90 g/d and 25 g/d per 10 MJ, respectively. Fasting blood samples at wk. 0 (baseline) and wk. 12 were analyzed for LDL particle size distribution and cholesterol content using nuclear magnetic resonance (NMR) spectroscopy. RESULTS: A total of 85 subjects [mean ± SD age: 54.0 ± 12.8 y; BMI: 28.7 ± 3.6 kg/m2] completed the study. Overall, regular-fat cheese did not impact lipoprotein particle number and size differently than reduced-fat cheese. In men (n = 23), the REG diet decreased total LDL particle number (LDL-P, - 223.2 ± 91.1 nmol/l, P = 0.01) compared with the RED diet. The reduction was primarily in the medium-sized LDL fraction (- 128.5 ± 51.8 nmol/l, P = 0.01). In women (n = 62), the REG diet increased the concentration of cholesterol in the small high density lipoprotein (HDL) particles compared with the CHO diet (2.9 ± 1.0 mg/dl, P = 0.006). CONCLUSION: Overall, regular-fat cheese did not alter LDL particle size distribution compared to reduced-fat cheese after a 12 wk. intervention in subjects with ≥2 MetS risk factors. However, our results suggest that lipoprotein response to cheese intake is gender-specific. This warrants further investigation. TRIAL REGISTRATION: This trial was registered at Clinicaltrials.gov as NCT0261471. Registered 30 November 2015 - Retrospectively registered.

Whole dairy matrix or single nutrients in assessment of health effects: current evidence and knowledge gaps.

Foods consist of a large number of different nutrients that are contained in a complex structure. The nature of the food structure and the nutrients therein (i.e., the food matrix) will determine the nutrient digestion and absorption, thereby altering the overall nutritional properties of the food. Thus, the food matrix may exhibit a different relation with health indicators compared to single nutrients studied in isolation. The evidence for a dairy matrix effect was presented and discussed by an expert panel at a closed workshop, and the following consensus was reached: 1) Current evidence does not support a positive association between intake of dairy products and risk of cardiovascular disease (i.e., stroke and coronary heart disease) and type 2 diabetes. In contrast, fermented dairy products, such as cheese and yogurt, generally show inverse associations. 2) Intervention studies have indicated that the metabolic effects of whole dairy may be different than those of single dairy constituents when considering the effects on body weight, cardiometabolic disease risk, and bone health. 3) Different dairy products seem to be distinctly linked to health effects and disease risk markers. 4) Different dairy structures and common processing methods may enhance interactions between nutrients in the dairy matrix, which may modify the metabolic effects of dairy consumption. 5) In conclusion, the nutritional values of dairy products should not be considered equivalent to their nutrient contents but, rather, be considered on the basis of the biofunctionality of the nutrients within dairy food structures. 6) Further research on the health effects of whole dairy foods is warranted alongside the more traditional approach of studying the health effects of single nutrients. Future diet assessments and recommendations should carefully consider the evidence of the effects of whole foods alongside the evidence of the effects of individual nutrients. Current knowledge gaps and recommendations for priorities in future research on dairy were identified and presented.

Effects of butter high in ruminant trans and monounsaturated fatty acids on lipoproteins, incorporation of fatty acids into lipid classes, plasma C-reactive protein, oxidative stress, hemostatic variables, and insulin in healthy young men.

BACKGROUND: Evidence suggests that ruminant trans fatty acids (FAs), such as vaccenic acid, do not increase the risk of ischemic heart disease (IHD). However, the effects of ruminant trans FAs on risk markers of IHD have been poorly investigated. OBJECTIVE: The objective was to investigate the effect of butter with a naturally high content of vaccenic acid and a concomitantly higher content of monounsaturated FAs on classic and novel risk markers of IHD. DESIGN: In a double-blind, randomized, 5-wk, parallel intervention study, 42 healthy young men were given 115 g fat/d from test butter that was high in vaccenic acid (3.6 g vaccenic acid/d) or a control butter with a low content of vaccenic acid. Blood and urine samples were collected before and after the intervention. RESULTS: The intake of the vaccenic acid-rich diet resulted in 6% and 9% lower total cholesterol and plasma HDL-cholesterol concentrations, respectively, than did the intake of the control diet (P = 0.05 and 0.002, respectively), whereas the ratio of total to HDL cholesterol did not differ significantly between the groups. The FA composition of lipid classes reflected the FAs' proportion of the test butter. No other differences were observed. CONCLUSIONS: Butter high in ruminant trans and monounsaturated FAs resulted in significantly lower total and HDL cholesterol than did the control butter with higher amounts of saturated FAs. It may be that the differences were due to the greater content of monounsaturated FAs and the lesser content of saturated FAs in the butter rich in ruminant trans FAs, rather than to the content of vaccenic acid per se.

Milk and dairy products: good or bad for human health? An assessment of the totality of scientific evidence.

BACKGROUND: There is scepticism about health effects of dairy products in the public, which is reflected in an increasing intake of plant-based drinks, for example, from soy, rice, almond, or oat. OBJECTIVE: This review aimed to assess the scientific evidence mainly from meta-analyses of observational studies and randomised controlled trials, on dairy intake and risk of obesity, type 2 diabetes, cardiovascular disease, osteoporosis, cancer, and all-cause mortality. RESULTS: The most recent evidence suggested that intake of milk and dairy products was associated with reduced risk of childhood obesity. In adults, intake of dairy products was shown to improve body composition and facilitate weight loss during energy restriction. In addition, intake of milk and dairy products was associated with a neutral or reduced risk of type 2 diabetes and a reduced risk of cardiovascular disease, particularly stroke. Furthermore, the evidence suggested a beneficial effect of milk and dairy intake on bone mineral density but no association with risk of bone fracture. Among cancers, milk and dairy intake was inversely associated with colorectal cancer, bladder cancer, gastric cancer, and breast cancer, and not associated with risk of pancreatic cancer, ovarian cancer, or lung cancer, while the evidence for prostate cancer risk was inconsistent. Finally, consumption of milk and dairy products was not associated with all-cause mortality. Calcium-fortified plant-based drinks have been included as an alternative to dairy products in the nutrition recommendations in several countries. However, nutritionally, cow's milk and plant-based drinks are completely different foods, and an evidence-based conclusion on the health value of the plant-based drinks requires more studies in humans. CONCLUSION: The totality of available scientific evidence supports that intake of milk and dairy products contribute to meet nutrient recommendations, and may protect against the most prevalent chronic diseases, whereas very few adverse effects have been reported.

High intake of regular-fat cheese compared with reduced-fat cheese does not affect LDL cholesterol or risk markers of the metabolic syndrome: a randomized controlled trial.

BACKGROUND: Regular-fat cheese contains a high amount of saturated fat. Therefore, dietary guidelines in many countries recommend the consumption of reduced-fat cheese as opposed to regular-fat cheese. However, the negative effect of regular-fat cheese is still under debate. OBJECTIVES: The aim was to compare the effects of regular-fat cheese with an equal amount of reduced-fat cheese and an isocaloric amount of carbohydrate-rich foods on LDL cholesterol and risk factors for the metabolic syndrome (MetS). DESIGN: The study was a 12-wk randomized parallel intervention preceded by a 2-wk run-in period. A total of 164 subjects with ≥2 MetS risk factors were randomly allocated to 1 of 3 intervention groups: regular-fat cheese (REG), reduced-fat cheese (RED), or a no-cheese, carbohydrate control (CHO) group. Subjects in the REG and RED groups replaced part of their daily habitual diet with 80 g cheese/10 MJ, whereas subjects in the CHO group did the same with bread and jam corresponding to 90 g and 25 g/10 MJ, respectively. RESULTS: A total of 139 subjects completed the intervention. The primary outcome, LDL cholesterol, was not significantly different between the REG and RED diets or between the REG and CHO diets. There was no significant difference in HDL cholesterol between the REG and RED diets, but HDL cholesterol tended to be higher with the REG diet than with the CHO diet (0.06 ± 0.03 mmol/L; P = 0.07). Insulin, glucose, and triacylglycerol concentrations as well as blood pressure and waist circumference did not differ significantly between the 3 diets. CONCLUSION: A high daily intake of regular-fat cheese for 12 wk did not alter LDL cholesterol or MetS risk factors differently than an equal intake of reduced-fat cheese or an isocaloric amount of carbohydrate-rich foods. This trial was registered at www.clinicaltrials.gov as NCT02616471.

Influence of stearic acid on hemostatic risk factors in humans.

Stearic acid has been claimed to be prothrombotic. Elevated plasma factor VII coagulant activity (FVIIc) may raise the risk of coronary thrombosis in the event of plaque rupture. Fibrinogen, an acute-phase protein, is necessary for normal blood clotting; however, elevated levels of fibrinogen increase the risk of coronary heart disease (CHD). Here I report the results of three controlled, human dietary intervention studies, which used a randomized crossover design to investigate the hemostatic effects of stearic acid-rich test diets in healthy young men. A diet high in stearic acid (shea butter) resulted in a 13% lower fasting plasma FVIIc than a high palmitic acid diet, and was 18% lower than a diet high in myristic and lauric acids (P = 0.001) after 3 wk of intervention. The stearic acid-rich test fat increased plasma fibrinogen concentrations slightly compared with the myristic-lauric acid diet (P < 0.01). When investigating the acute effects of fatty meals, those high in stearic acid (synthesized test fat) resulted in a smaller postprandial increase in FVII than those high in trans and oleic FA, indicating a smaller increase in activated FVII after ingesting stearic acid compared with fats high in monounsaturated FA, probably caused by lower postprandial lipemia. Thus, the present investigations did not find dietary stearic acid to be more thrombogenic, in either fasting effects compared with other long-chain FA, or in acute effects compared with dietary unsaturated FA, including trans monounsaturated FA. The slightly increased effect on fasting plasma fibrinogen may be biologically insignificant, but it should be investigated further.

Butter increased total and LDL cholesterol compared with olive oil but resulted in higher HDL cholesterol compared with a habitual diet.

BACKGROUND: Butter is known to have a cholesterol-raising effect and, therefore, has often been included as a negative control in dietary studies, whereas the effect of moderate butter intake has not been elucidated to our knowledge. OBJECTIVE: We compared the effects of moderate butter intake, moderate olive oil intake, and a habitual diet on blood lipids, high-sensitivity C-reactive protein (hsCRP), glucose, and insulin. DESIGN: The study was a controlled, double-blinded, randomized 2 × 5-wk crossover dietary intervention study with a 14-d run-in period during which subjects consumed their habitual diets. The study included 47 healthy men and women (mean ± SD total cholesterol: 5.22 ± 0.90 mmol/L) who substituted a part of their habitual diets with 4.5% of energy from butter or refined olive oil. RESULTS: Study subjects were 70% women with a mean age and body mass index (in kg/m²) of 40.4 y and 23.5, respectively. Butter intake increased total cholesterol and LDL cholesterol more than did olive oil intake (P < 0.05) and the run-in period (P < 0.005 and P < 0.05, respectively) and increased HDL cholesterol compared with the run-in period (P < 0.05). No difference in effects was observed for triacylglycerol, hsCRP, insulin, and glucose concentrations. The intake of saturated fatty acids was significantly higher in the butter period than in the olive oil and run-in periods (P < 0.0001). CONCLUSIONS: Moderate intake of butter resulted in increases in total cholesterol and LDL cholesterol compared with the effects of olive oil intake and a habitual diet (run-in period). Furthermore, moderate butter intake was also followed by an increase in HDL cholesterol compared with the habitual diet. We conclude that hypercholesterolemic people should keep their consumption of butter to a minimum, whereas moderate butter intake may be considered part of the diet in the normocholesterolemic population.

Diets with high-fat cheese, high-fat meat, or carbohydrate on cardiovascular risk markers in overweight postmenopausal women: a randomized crossover trial.

BACKGROUND: Heart associations recommend limited intake of saturated fat. However, effects of saturated fat on low-density lipoprotein (LDL)-cholesterol concentrations and cardiovascular disease risk might depend on nutrients and specific saturated fatty acids (SFAs) in food. OBJECTIVE: We explored the effects of cheese and meat as sources of SFAs or isocaloric replacement with carbohydrates on blood lipids, lipoproteins, and fecal excretion of fat and bile acids. DESIGN: The study was a randomized, crossover, open-label intervention in 14 overweight postmenopausal women. Three full-diet periods of 2-wk duration were provided separated by 2-wk washout periods. The isocaloric diets were as follows: 1) a high-cheese (96-120-g) intervention [i.e., intervention containing cheese (CHEESE)], 2) a macronutrient-matched nondairy, high-meat control [i.e., nondairy control with a high content of high-fat processed and unprocessed meat in amounts matching the saturated fat content from cheese in the intervention containing cheese (MEAT)], and 3) a nondairy, low-fat, high-carbohydrate control (i.e., nondairy low-fat control in which the energy from cheese fat and protein was isocalorically replaced by carbohydrates and lean meat (CARB). RESULTS: The CHEESE diet caused a 5% higher high-density lipoprotein (HDL)-cholesterol concentration (P = 0.012), an 8% higher apo A-I concentration (P < 0.001), and a 5% lower apoB:apo A-I ratio (P = 0.008) than did the CARB diet. Also, the MEAT diet caused an 8% higher HDL-cholesterol concentration (P < 0.001) and a 4% higher apo A-I concentration (P = 0.033) than did the CARB diet. Total cholesterol, LDL cholesterol, apoB, and triacylglycerol were similar with the 3 diets. Fecal fat excretion was 1.8 and 0.9 g higher with the CHEESE diet than with CARB and MEAT diets (P < 0.001 and P = 0.004, respectively) and 0.9 g higher with the MEAT diet than with the CARB diet (P = 0.005). CHEESE and MEAT diets caused higher fecal bile acid excretion than did the CARB diet (P < 0.05 and P = 0.006, respectively). The dominant type of bile acids excreted differed between CHEESE and MEAT diets. CONCLUSIONS: Diets with cheese and meat as primary sources of SFAs cause higher HDL cholesterol and apo A-I and, therefore, appear to be less atherogenic than is a low-fat, high-carbohydrate diet. Also, our findings confirm that cheese increases fecal fat excretion. This trial was registered at clinicaltrials.gov as NCT01739153.