Table 4 - uploaded by Robert F Grimble
Content may be subject to copyright.

Fractional trans-vaccenic acid concentration (g/100 g) in plasma lipids and peripheral blood mononuclear cells (PBMC) (Mean values and standard deviations)
Source publication
The present study investigated whether consuming dairy products naturally enriched in cis-9, trans-11 (c9,t11) conjugated linoleic acid (CLA) by modification of cattle feed increases the concentration of this isomer in plasma and cellular lipids in healthy men. The study had a double-blind cross-over design. Subjects aged 34-60 years consumed dairy...
Contexts in source publication
Context 1
... of trans-vaccenic acid in plasma and peripheral blood mononuclear cell lipids tVA was detected in plasma PC, TAG and NEFA fractions and PBMC at baseline and after the intervention periods. However, tVA was not detected in the CE fraction (Table 4). There was no significant difference in the fractional concentration of tVA between plasma PC, TAG and NEFA, and PBMC at the start of the intervention period. ...
Context 2
... concentration of tVA between the start of the control interven- tion and the start of the intervention with the CLA-enriched dairy products (Table 4). tVA concentration in plasma PC was lower (36 %) at the end of the intervention period compared with the start after consumption of the control products, but there was no sig- nificant change in the tVA content of TAG, NEFA or PBMC ( Table 4). ...
Context 3
... concentration of tVA between the start of the control interven- tion and the start of the intervention with the CLA-enriched dairy products (Table 4). tVA concentration in plasma PC was lower (36 %) at the end of the intervention period compared with the start after consumption of the control products, but there was no sig- nificant change in the tVA content of TAG, NEFA or PBMC ( Table 4). Consumption of the CLA-enriched products, which contained more then 10-fold higher tVA than the control products, was associ- ated with an increase in the proportion of tVA in plasma PC (65 %), TAG (98 %) and PBMC (84 %), but there was no significant differ- ence in the tVA content of the NEFA fraction (Table 4). ...
Context 4
... concentration in plasma PC was lower (36 %) at the end of the intervention period compared with the start after consumption of the control products, but there was no sig- nificant change in the tVA content of TAG, NEFA or PBMC ( Table 4). Consumption of the CLA-enriched products, which contained more then 10-fold higher tVA than the control products, was associ- ated with an increase in the proportion of tVA in plasma PC (65 %), TAG (98 %) and PBMC (84 %), but there was no significant differ- ence in the tVA content of the NEFA fraction (Table 4). These effects were reflected in significant differences at the end of the intervention period between consuming the control or CLA- enriched dairy products (Table 4). ...
Context 5
... of the CLA-enriched products, which contained more then 10-fold higher tVA than the control products, was associ- ated with an increase in the proportion of tVA in plasma PC (65 %), TAG (98 %) and PBMC (84 %), but there was no significant differ- ence in the tVA content of the NEFA fraction (Table 4). These effects were reflected in significant differences at the end of the intervention period between consuming the control or CLA- enriched dairy products (Table 4). There was no significant relationship between the proportion of tVA in any of the lipid pools measured at the start of the interven- tion or after consuming the control foods. ...
Similar publications
The seasonal variation in conjugated linoleic acid (CLA) and vaccenic acid (VA) concentrations in sheep dairy products and the extent of their transfer from milk fat to cheese and ricotta fat were investigated. Samples were collected from 2 sheep milk processing plants in North Sardinia (Italy) every 2 wk from March through June. Concentrations of...
Dietary addition of either conjugated linoleic acid (CLA) or n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) has been shown to alter adiposity and circulating lipids, risk markers of cardiovascular diseases. However, CLA may decrease insulin sensitivity, an effect that may be reversed by n-3 LC-PUFA. Thus, the potential of CLA plus n-3 LC...
It may be desirable to increase the level of conjugated linoleic acid (CLA) in milk as a health benefit in human nutrition. The purpose of this work was to separate the effects of linoleic and linolenic acids on CLA production in dairy cows and to determine to what extent endogenous synthesis contributes to cis-9, trans-11 CLA concentration in milk...
To examine the effects of two different conjugated linoleic acid (CLA) isomers at two different intakes on body composition in overweight humans.
Eighty-one middle-aged, overweight, healthy men and women participated in this bicentric, placebo-controlled, double-blind, randomized study. For 6 weeks (run-in period), all subjects consumed daily a dri...
Citations
... Studies in animals suggest that disorders of PCs and/or PEs and their ratios may contribute to many risk factors for diabetes, such as insulin resis-tance [19,20]. It has been demonstrated that a Mediterranean diet can change circulating GPL profiles as well as concentrations of specific lipid metabolites [21][22][23][24]. These findings highlight the effect of diet on glycerophospholipid metabolites. ...
Background/Objectives: This study aimed to investigate the effects of fish oil-derived omega-3 polyunsaturated fatty acids (omega-3 PUFAs) on gut microbiota and serum lipid metabolites in T2DM. Methods: In a three-month, randomized, double-blind, placebo-controlled study, 110 T2DM patients received either fish oil (n = 55) or corn oil (n = 55) capsules daily. Serum lipids, glycemic parameters, gut microbiota diversity, and lipidomics were assessed. Results: This study found that fish oil-derived omega-3 PUFAs intervention did not significantly lower the fasting plasma glucose levels when compared with the baseline level (p > 0.05). However, serum fasting blood glucose (p = 0.039), glycosylated hemoglobin levels (p = 0.048), HOMA-IR (p = 0.022), total cholesterol (p < 0.001), triglyceride (p = 0.034), LDL cholesterol (p = 0.048), and non-HDL levels (p = 0.046) were significantly lower in the fish oil group compared with the corn oil group after three months of intervention. Also, it altered glycerophospholipid metabolism and gut microbiota. After three months, the fish oil group showed a significantly lower abundance of Desulfobacterota compared with the corn oil control group (p = 0.003), with reduced levels of Colidextribacter (p = 0.002), Ralstonia (p = 0.021), and Klebsiella (p = 0.013). Conversely, the abundance of Limosilactobacillus (p = 0.017), Lactobacillus (p = 0.011), and Haemophilus (p = 0.018) increased significantly. In addition, relevant glycolipid metabolism indicators showed significant correlations with the altered profiles of serum lipid metabolites, intestinal bacteria, and fungi. Conclusions: This study highlights the impact of fish oil-derived omega-3 PUFAs on intestinal microbiota structure and function in patients with type 2 diabetes. The observed decrease in pathogenic bacterial species and the enhancement of beneficial species may have significant implications for gut health and systemic inflammation, both of which are pivotal in managing diabetes. Further research is warranted to comprehensively elucidate the long-term benefits and underlying mechanisms of these microbiota alterations.
... Vaccenic acid is the primary type of fat from dairy products, such as milk, butter, and yogurt. Increasing consumption of dairy products increases the concentration of vaccenic acid in plasma 52 . The importance of vaccenic acid for brain health may lie in its metabolic conversion to conjugated linoleic acid, or CLA 53 . ...
The emerging field of Nutritional Cognitive Neuroscience aims to uncover specific foods and nutrients that promote healthy brain aging. Central to this effort is the discovery of nutrient profiles that can be targeted in nutritional interventions designed to promote brain health with respect to multimodal neuroimaging measures of brain structure, function, and metabolism. The present study therefore conducted one of the largest and most comprehensive nutrient biomarker studies examining multimodal neuroimaging measures of brain health within a sample of 100 older adults. To assess brain health, a comprehensive battery of well-established cognitive and brain imaging measures was administered, along with 13 blood-based biomarkers of diet and nutrition. The findings of this study revealed distinct patterns of aging, categorized into two phenotypes of brain health based on hierarchical clustering. One phenotype demonstrated an accelerated rate of aging, while the other exhibited slower-than-expected aging. A t-test analysis of dietary biomarkers that distinguished these phenotypes revealed a nutrient profile with higher concentrations of specific fatty acids, antioxidants, and vitamins. Study participants with this nutrient profile demonstrated better cognitive scores and delayed brain aging, as determined by a t-test of the means. Notably, participant characteristics such as demographics, fitness levels, and anthropometrics did not account for the observed differences in brain aging. Therefore, the nutrient pattern identified by the present study motivates the design of neuroscience-guided dietary interventions to promote healthy brain aging.
... RA and VA have been previously described as dairy fat consumption markers in humans [38]. Burdge et al. [39] demonstrated that, when RA was consumed in a diet, it was incorporated in all lipid fractions, but preferentially in CE, while VA was preferentially incorporated in TGs and could not be found in CE. This fact can partially explain the higher concentration of RA than that of VA in plasma (the opposite occurred in MF; Supplementary Table S1), as the CE concentration in the plasma was higher than that of the TGs (Table 2). ...
The relationship between milk fat intake (because of its high saturated fatty acid content) and the risk of suffering from cardiovascular diseases remains controversial. Thus, Golden Syrian hamsters were fed two types of fat—sheep milk fat that was rich in rumenic (cis9,trans11-18:2) and vaccenic (trans11-18:1) acids and olive oil—and two doses (a high- or normal-fat diet) for 14 weeks, and markers of lipid metabolism and atherosclerosis evolution were analyzed. The results revealed that the type and percentage of fat affected most plasma biochemical parameters related to lipid metabolism, while only the expression of five (CD36, SR-B1, ACAT, LDLR, and HMG-CoAR) of the studied lipid-metabolism-related genes was affected by these factors. According to aortic histology, when ingested in excess, both fats caused a similar increase in the thickness of fatty streaks, but the high-milk-fat-based diet caused a more atherogenic plasma profile. The compositions of the fats that were used, the results that were obtained, and the scientific literature indicated that the rumenic acid present in milk fat would regulate the expression of genes involved in ROS generation and, thus, protect against LDL oxidation, causing an effect similar to that of olive oil.
... Weight-stable men and women [aged 25-70 y; BMI (kg/m 2 ): [19][20][21][22][23][24][25][26][27][28][29][30][31][32] with moderate risk of developing CVD were enrolled into the study, which was conducted at the Hugh Sinclair Unit of Human Nutrition, University of Reading (Berkshire, United Kingdom) between February 2014 and April 2016. Details of the eligibility criteria are presented elsewhere (5,15). ...
... Total lipids were extracted from K3-EDTA plasma samples isolated from blood samples collected at 0, 180, 300, and 420 min. Total plasma lipid was extracted using the method by Burdge et al. (24), and as described previously (8). In brief, FA methyl esters (FAMEs) were resolved on a 100-m fused silica capillary column (CP-SIL 88; Agilent Technologies, UK) using a gas chromatograph (Bruker 350; Bruker, Germany), with a flame ionization detector (25). ...
Background
Longer-term consumption of saturated fatty acid (SFA)-reduced, monounsaturated fatty acid (MUFA)-enriched dairy products have been reported to improve fasting flow-mediated vasodilation (FMD). Yet, their impact on endothelial function in the postprandial state warrants investigation.
Objectives
To compare the impact of a fatty acid (FA)-modified with a conventional (control) dairy diet on the postprandial %FMD (primary outcome) and systemic cardiometabolic responses to representative meals, and retrospectively explore whether treatment effects differ by apolipoprotein (APO)E or endothelial nitric oxide synthase (eNOS) Glu298Asp gene polymorphisms.
Methods
In a crossover-design randomized controlled study, 52 adults with moderate cardiovascular disease risk consumed dairy products [38% total energy intake (%TE) from fat: FA-modified (target: 16%TE SFAs; 14%TE MUFAs) or control (19%TE SFAs; 11%TE MUFAs)] for 12-wk, separated by an 8-wk washout. Blood sampling and FMD measurements (0-480 min) were performed pre- and post-intervention after sequential mixed meals that were representative of the assigned dairy diets (0 min; ∼50 g fat; 330 min; ∼30 g fat).
Results
Relative to pre-intervention (∆), the FA-modified dairy diet and meals (treatment) attenuated the increase in the incremental AUC (iAUC), but not AUC, for the %FMD response observed with the conventional treatment (–135 ± 69 vs + 199 ± 82% x min; P = 0.005). The ∆ iAUC, but not AUC, for the apoB response decreased after FA-modified yet increased after the conventional treatment (–4 ± 3 vs + 3 ± 3 mg/mL × min; P = 0.004). The ∆ iAUC decreased for total plasma SFAs (P = 0.003) and trans 18:1 (P < 0.0001) and increased for cis-MUFAs (P < 0.0001) following conventional, relative to the FA-modified treatment. No treatment x APOE- or eNOS-genotype interactions were evident for any outcome.
Conclusions
This study provides novel insights into the longer-term effects of FA-modified dairy food consumption on postprandial cardiometabolic responses.
Clinical Trial Registry: Unique identifier: NCT02089035. URL: https://clinicaltrials.gov/ct2/show/NCT02089035
... Besides, these FA have been related to beneficial health effects. For example, RA has been related to reduced risk of cancer, atherosclerosis and obesity (Burdge et al., 2005) and BCFA have been shown to have anti-cancer activity (Vlaeminck et al., 2006). ...
... In hamsters' erythrocytes, as the variability is lower, the differences are significant. In addition, it has been demonstrated that, when consumed in the diet, RA is incorporated in all lipid fractions, but preferentially in CE, while VA is preferentially incorporated in TG and cannot be found in CE (Burdge et al., 2005). This fact can also account for the higher concentration of RA than VA in plasma, as CE are in higher proportion in plasma than TG, as commented before. ...
Hamsters have been long accepted as animal models to study the lipid metabolism in humans. However, very few scientific works described in detail the fatty acid (FA) composition of plasma and erythrocytes in hamsters in relation to their dietary intake, and none work was found comparing them with that described in humans. Therefore, a study was carried out to compare the effect of ingesting olive oil or dairy fat, as part of an equilibrated diet in healthy subjects, on plasma and erythrocytes FA composition. More than 40 FA were detected in samples of both species. It was demonstrated that plasma total FA (TFA) concentration and FA profiles are similar in humans and hamsters. In both species linoleic, oleic and palmitic acids are the main FA and accounted for the 70% of TFA. Differences found between species can be explained by differences in the dietary intake and differences in the proportion of triglycerides, cholesteryl esters and phospholipid fractions in plasma of both species. Changes in dietary FA intake causes similar changes in FA concentration in the plasma of both species and can be explained by the same metabolic processes. The erythrocyte FA profile differs more between the two species. Moreover, unlike humans, the FA profile of hamster erythrocytes is more sensitive to changes in dietary FA than that of plasma.
... Previously, several intervention studies showed that a Mediterranean diet, low-glycaemic-index diet, or foods such as fish, dairy produce and soybean oil could alter circulating GPL profiles and/or concentrations of specific lipid metabolites [13][14][15][16][17]. A Mediterranean diet intervention reduced levels of PCs containing fatty acids with long chains (C16-20) and less double bonds, but increased PCs [13] containing fatty acids with very long chains (C20-22) and more double bonds. ...
Aims/hypothesis
Glycerophospholipid (GPL) perturbance was linked to the pathogenesis of diabetes in animal studies but prospective studies in humans are rare, particularly in Asians. We aimed to investigate the associations between plasma GPLs and incident diabetes and to explore effects of lifestyle on the associations in a Chinese population.
Methods
The study included 1877 community-dwelling Chinese individuals aged 50–70 years (751 men and 1126 women), free of diabetes at baseline and followed for 6 years. A total of 160 GPL species were quantified in plasma at baseline by using high-throughput targeted lipidomics. Log-Poisson regression was used to assess the associations between GPLs and incidence of diabetes.
Results
Over the 6 years of follow-up, 499 participants (26.6%) developed diabetes. After multivariable adjustment, eight GPLs were positively associated with incident diabetes (RRper SD 1.13–1.25; all false-discovery rate [FDR]-corrected p < 0.05), including five novel GLPs, namely phosphatidylcholines (PCs; 16:0/18:1, 18:0/16:1, 18:1/20:3), lysophosphatidylcholine (LPC; 20:3) and phosphatidylethanolamine (PE; 16:0/16:1), and three reported GPLs (PCs 16:0/16:1, 16:0/20:3 and 18:0/20:3). In network analysis, a PC-containing module was positively associated with incident diabetes (RRper SD 1.16 [95% CI 1.06, 1.26]; FDR-corrected p < 0.05). Notably, three of the diabetes-associated PCs (16:0/16:1, 16:0/18:1 and 18:0/16:1) and PE (16:0/16:1) were associated not only with fatty acids in the de novo lipogenesis (DNL) pathway, especially 16:1n-7 (Spearman correlation coefficients = 0.35–0.62, p < 0.001), but also with an unhealthy dietary pattern high in refined grains and low in fish, dairy and soy products (|factor loadings| ≥0.2). When stratified by physical activity levels, the associations of the eight GPLs and the PC module with incident diabetes were stronger in participants with lower physical activity (RRper SD 1.24–1.49, FDR-corrected p < 0.05) than in those with the median and higher physical activity levels (RRper SD 1.03–1.12, FDR-corrected p ≥ 0.05; FDR-corrected pinteraction < 0.05).
Conclusions/interpretation
Eight GPLs, especially PCs associated with the DNL pathway, were positively associated with incident diabetes in a cohort of Chinese men and women. The associations were most prominent in participants with a low level of physical activity.
Graphical abstract
... For the determination of whole blood culture LPS-stimulated cytokines, blood samples collected into K 2 -EDTA tubes were not centrifuged and stored at 4 • C until processing as previously described (24). Briefly, whole-blood samples were diluted 1:9 with Roswell Park Memorial Institute 1640 medium (Sigma) supplemented with 1% antibiotics, 1% l-glutamine, and 1% nonessential amino acids (Bioscience). ...
... To assess changes in plasma FA status in response to our sequential 2meal fat challenge, we measured the plasma total lipid FA pool; this pool is representative of immediate FA intake and gives an indication of all FA-containing plasma lipid fractions, including cholesteryl esters, NEFAs, phospholipids, and TG (25). Total lipid in 0.5 mL K 3 -EDTA plasma was extracted using 5.0 mL chloroform-methanol [2:1, vol:vol; Burdge et al. (24)]. After shaking for 15 min, the aqueous and solvent layers were separated using centrifugation (1125 × g for 10 min at 4 • C), and the solvent layer dried under nitrogen at 40 • C. Dried lipid was redissolved in 0.5 mL toluene and methylated by the addition of 1.0 mL 2% H 2 SO 4 in methanol, and incubated for 2 h at 50 • C. ...
Background
Chronic consumption of dairy products with an SFA-reduced, MUFA-enriched content was shown to impact favorably on brachial artery flow-mediated dilatation (FMD). However, their acute effect on postprandial cardiometabolic risk biomarkers requires investigation.
Objective
The effects of sequential high-fat mixed meals rich in fatty acid (FA)–modified or conventional (control) dairy products on postprandial FMD (primary outcome) and systemic cardiometabolic biomarkers in adults with moderate cardiovascular risk (≥50% above the population mean) were compared.
Methods
In a randomized crossover trial, 52 participants [mean ± SEM age: 53 ± 2 y; BMI (kg/m2) 25.9 ± 0.5] consumed a high-dairy-fat breakfast (0 min; ∼50 g total fat: modified: 25 g SFAs, 20 g MUFAs; control: 32 g SFAs, 12 g MUFAs) and lunch (330 min; ∼30 g total fat; modified: 15 g SFAs, 12 g MUFAs; control: 19 g SFAs, 7 g MUFAs). Blood samples were obtained before and until 480 min after breakfast, with FMD assessed at 0, 180, 300, and 420 min. Data were analyzed by linear mixed models.
Results
Postprandial changes in cardiometabolic biomarkers were comparable between the different dairy meals, with the exception of a tendency for a 4% higher AUC for the %FMD response following the modified-dairy-fat meals (P = 0.075). Plasma total lipid FA analysis revealed that incremental AUC responses were 53% lower for total SFAs, 214% and 258% higher for total cis-MUFAs (predominantly cis-9 18:1), and trans-18:1, respectively, following the modified relative to the control dairy meals (all P < 0.0001).
Conclusions
In adults at moderate cardiovascular risk, acute consumption of sequential high-fat meals containing FA-modified dairy products had little impact on postprandial endothelial function or systemic cardiometabolic biomarkers, but a differential effect on the plasma total lipid FA profile, relative to conventional dairy fat meals.
This trial was registered at clinicaltrials.gov as NCT02089035.
... The anti-atherogenic effects observed with CLAs are presumably mediated not only by CLAs themselves but also by their metabolites [22]. A double-blind crossover human trial confirmed that consuming dairy products that are naturally enriched in cis-9, trans-11 (c9,t11) CLA by modification of cattle feed increases the concentration of this isomer in the plasma and cellular lipids of healthy men [23]. Conjugated linoleic acid improves blood pressure, a risk factor for cardiovascular disease (CVD), by increasing adiponectin and endothelial nitric oxide synthase activity [24]. ...
Conjugated linoleic acid (CLA) is a dietary polyunsaturated fatty acid found in animal fats such as red meat and dairy products [1]. Only trace amounts of CLA occur naturally in plant lipids, but various CLA isomers are produced during the chemical hydrogenation of fats [2]. While cis-9,trans-11-(c9,t11)-CLA is predominantly found in meat and dairy products, trans-9,trans-11-(t9,t11)-CLA is a constituent of vegetable oils. The isomers of CLA, cis-9, trans-11 (c9t11)-CLA and trans-10, and cis-12 (t10c12)-CLA are known to exert a variety of beneficial effects on the body [1,3]. CLA isomers are elongated and desaturated in a different pathway [4]. These isomers activate different nuclear receptors and, thus, they differentially regulate the expression of those genes related to lipid metabolism. Recently, den Hartigh [5] extensively reviewed the pre-clinical and human studies which have been conducted using CLAs. This work concluded that CLA has efficacy against cancer, obesity, and atherosclerosis. The involvement of gut bacteria was also highlighted. The Food and Drug Adminisrtation (FDA) in the USA defines trans fats as all unsaturated fatty acids that contain one or more nonconjugated double bond in a trans configuration. However, the CLA present in any food which contains conjugated trans fatty acids is not labelled as a trans fat. CLA is approved as being generally recognized as safe (GRAS) for a mixture of approximately 60%-90% of the cis-9, trans-11, and trans-10,cis-12 isomers in about a 50:50 ratio. The normal CLA content of human plasma is approximately 0.1% of the total fatty acids [6]. The consumption of up to 6 g CLA/day for one year or 3.4 g CLA/day for up to 2 years is considered to be safe at this moment [7-9]. The mean daily intake of cis-9, trans-11 CLA is estimated to be 97.5 mg/d in the UK, which was calculated based on the daily intake of foodstuffs containing CLA isomers [10]. Conjugated linoleic acid (CLA) isomers offer a high stability in thermal processes, which ensures optimal meat quality after cooking [11]. Thus, it is expected that CLA will be added to a number of food products to improve health perspectives. However, there are few CLA-fortified foods available, indicating some of the unresolved issues of using CLA as a food ingredient [12]. Two primary challenges possibly limit the efficacies of CLAs, as den Hartigh [5] discussed in their review. Firstly, CLA isomers activate different nuclear receptors and the expression of the genes related to lipid metabolism. Since each isomer has specific effects, it is challenging to obtain isomer specific food products. Secondly, the majority of the studies have been conducted on the effects of the short-term supplementation of CLA on cardiovascular effects including hypertension [13]. Den Hartigh [5] has discussed these issues well in their review.
... As is common practice in the literature, TFA levels expressed as proportions of total FAs have been described in plasma lipids [55], different plasma lipid fractions [58,59], erythrocytes [60][61][62], blood immune cells [58,59], adipose tissue [63][64][65][66], and breast milk [67,68] in humans; these data are summarised in Table 3. It is clear that 18-carbon TFAs make a significant contribution (i.e. ...
... As is common practice in the literature, TFA levels expressed as proportions of total FAs have been described in plasma lipids [55], different plasma lipid fractions [58,59], erythrocytes [60][61][62], blood immune cells [58,59], adipose tissue [63][64][65][66], and breast milk [67,68] in humans; these data are summarised in Table 3. It is clear that 18-carbon TFAs make a significant contribution (i.e. ...
Endothelial dysfunction is a proinflammatory state characterized by chronic activation of the endothelium, which leads to atherosclerosis and cardiovascular disease (CVD). Intake of trans fatty acids (TFAs) is associated with an increased risk of CVD. This risk is usually associated with industrial TFAs (iTFAs) rather than ruminant TFAs (rTFAs); however it is not clear how specific TFA isomers differ in their biological activity and mechanisms of action with regard to inflammation. Here we review the literature on 18carbon TFAs, including the research associating their intake or levels with CVD and studies relating 18carbon TFA exposure to modulation of inflammatory processes. The evidence associating iTFAs with CVD risk factors is fairly consistent and studies in humans usually show a relation between iTFAs and higher levels of inflammatory markers. In contrast, studies in humans, animals and in vitro suggest that rTFAs have null or mildly beneficial effects in cardiovascular health, metabolic parameters and inflammatory markers, although the evidence is not always consistent. More studies are needed to better identify the beneficial and detrimental effects of the different TFAs, including those with 18 carbons.
... Sunflower seeds were added to standard dairy cow feed to induce a ten-fold increase in CLA levels in their milkfat (4.22 g CLA/ 100 g butter fat versus 0.38 g CLA/100 g butter fat). The (Burdge et al. 2005). They added sunflower seeds and fish oil to standard cattle feed for 7 days to increase CLA in the dairy fat. ...
Background: Food recommendations to improve cancer prevention are generally based on epidemiologic data and remain inconsistent. These epidemiologic studies, while controversial, have generally produced results that caution against the consumption of high-fat foods, including eggs, red meat, and full-fat dairy, such as butter and cheese. Yet, limited data exist assessing the quality of individual sources of these foods and the effect each has after its consumption. This study set out to assess the impact sources of food within the same groups from animals raised differently on variables associated with health in human studies.
Methods and Materials: A search was conducted through MEDLINE, Embase, and PubMed. In total, twenty-nine studies met inclusion criteria, measuring physiologic changes in humans after consuming animal products following animal diet manipulation. A meta-analysis was attempted to assess the differences between the cohorts in these studies, but was aborted due to poor study quality, vast differences in study design, and a limited number of studies.
Results: Studies varied by animal, animal diet manipulation, food product, and overall design. Significant differences were present between groups eating the same food (cheese, beef, eggs, and butter) from animals raised differently, including levels of: conjugated linoleic acid, omega-3 fatty acids (alpha linoleic acid [ALA], docosahexaenoic acid [DHA], and eicosapentaenoic acid [EPA]), and inflammatory factors (triacyl glycerol [TAG], interleukin-6 [IL-6], interleukin-8 [IL-8], tumor necrosis factor [TNF], and C-reactive protein [CRP]). Lipid levels were minimally affected.
Conclusions: This work highlights differences in human health markers after consumption of the same foods from animals raised differently. Overall, lipid levels remained relatively neutral, but significant changes in inflammatory and other serum markers and phospholipids were present. Future studies and dietary recommendations should consider how animals are raised, as this can produce different effects on health markers.