Dietary Saturated Fatty Acids Research Articles

Substitution of dietary monounsaturated fatty acids from olive oil for saturated fatty acids from lard increases low-density lipoprotein apolipoprotein B-100 fractional catabolic rate in subjects with dyslipidemia associated with insulin resistance: a randomized controlled trial

BackgroundThe substitution of monounsaturated acids (MUFAs) for saturated fatty acids (SFAs) is recommended for cardiovascular disease prevention but its impact on lipoprotein metabolism in subjects with dyslipidemia associated with insulin resistance (IR) remains largely unknown. ObjectivesThis study aimed to evaluate the impact of substituting MUFAs for SFAs on the in vivo kinetics of apolipoprotein (apo)B-containing lipoproteins and on the plasma lipidomic profile in adults with IR-induced dyslipidemia. MethodsMales and females with dyslipidemia associated with IR (n = 18) were recruited for this crossover double-blind randomized controlled trial. Subjects consumed, in random order, a diet rich in SFAs (SFAs: 13.4%E; MUFAs: 14.4%E) and a diet rich in MUFAs (SFAs: 7.1%E; MUFAs: 20.7%E) in fully controlled feeding conditions for periods of 4 wk each, separated by a 4-wk washout. At the end of each diet, fasting plasma samples were taken together with measurements of the in vivo kinetics of apoB-containing lipoproteins. ResultsSubstituting MUFAs for SFAs had no impact on triglyceride-rich lipoprotein apoB-48 fractional catabolic rate (FCR) (Δ = –8.9%, P = 0.4) and production rate (Δ = 0.0%, P = 0.9), although it decreased very low-density lipoprotein apoB-100 pool size (PS) (Δ = −22.5%; P = 0.01). This substitution also reduced low-density lipoprotein cholesterol (LDL-C) (Δ = −7.0%; P = 0.01), non–high-density lipoprotein cholesterol (Δ = −2.5%; P = 0.04), and LDL apoB-100 PS (Δ = −6.0%; P = 0.05). These differences were partially attributed to an increase in LDL apoB-100 FCR (Δ = +1.6%; P = 0.05). The MUFA diet showed reduced sphingolipid concentrations and elevated glycerophospholipid levels compared with the SFA diet. ConclusionsThis study demonstrated that substituting dietary MUFAs for SFAs decreases LDL-C levels and LDL PS by increasing LDL apoB-100 FCR and results in an overall improved plasma lipidomic profile in individuals with IR-induced lipidemia. Trial registrationThis trial was registered as clinicaltrials.gov as NCT03872349.

Exploring the Interplay between Fatty Acids, Inflammation, and Type 2 Diabetes

Around 285 million people worldwide currently have type 2 diabetes and it is projected that this number will be surpassed by 2030. Therefore, it is of the utmost importance to enhance our comprehension of the disease’s development. The regulation of diet, obesity, and inflammation in type 2 diabetes is believed to play a crucial role in enhancing insulin sensitivity and reducing the risk of onset diabetes. Obesity leads to an increase in visceral adipose tissue, which is a prominent site of inflammation in type 2 diabetes. Dyslipidemia, on the other hand, plays a significant role in attracting activated immune cells such as macrophages, dendritic cells, T cells, NK cells, and B cells to visceral adipose tissue. These immune cells are a primary source of pro-inflammatory cytokines that are believed to promote insulin resistance. This review delves into the influence of elevated dietary free saturated fatty acids and examines the cellular and molecular factors associated with insulin resistance in the initiation of inflammation induced by obesity. Furthermore, it explores novel concepts related to diet-induced inflammation and its relationship with type 2 diabetes.

Effect of Olive Oil Hydrogel as a Fat Replacer in Beef Meatballs.

Meat and meat products are essential sources of dietary saturated fatty acids. However, excessive consumption of meat and meat products may be harmful to human health. The study evaluates the effect of fat replacement with hydrogels (olive oil in water emulsions gelled by gelatine) in meatballs. The effect of replacing fat with different ratios of hydrogel (control, 25 (F25), 50 (F50), 75 (F75) and 100 % (F100)) on the chemical (fatty acids and thiobarbituric acid reactive substances (TBARS)) and physical (cooking loss, diameter reduction, fat retention, water retention, colour and texture analysis) characteristics of the meatballs were analyzed. The fat content of raw meatball samples was reduced from (31.2±2.2) to (10.5±0.4) % in the sample with the highest fat substitution (F100). The energy levels of the F100 samples were almost 56 % lower than of the control group. Monounsaturated fatty acids (MUFAs) represented the dominant group in all substitution rates of the meatballs, followed by saturated fatty acids (SFAs) and finally polyunsaturated fatty acids (PUFAs). Among the raw meatball samples, the highest oxidation occurred in the F50 and F100 groups. However, it was determined that the difference between F25 and F75 and the difference between control and F75 were not statistically significant (p˃0.05). When the cooked samples were compared, the highest thiobarbituric acid (TBA) value was found in the F50 sample, followed by the F100 and F75 samples. The difference between the mean values of springiness and cohesiveness of the samples was not significant (p˃0.05). The hardness value of samples decreased significantly (p˂0.001) with >75 % fat replacement. It can be concluded that the oil replacement rate that may satisfy consumer demand without impairing the product technological and chemical quality should be <75 %. As the fat replacement ratio increases, the SFA content of cooked meatballs decreases, while the MUFA and PUFA contents increase. Considering the positive effects of reducing the intake of SFAs and increasing the intake of unsaturated fatty acids on non-communicable diseases such as cardiovascular diseases, fat replacement in meatballs is important for future developments.

Comparison of the impact of saturated fat from full-fat yogurt or low-fat yogurt and butter on cardiometabolic factors: a randomized cross-over trial.

Dairy foods are often a major contributor to dietary saturated fatty acids (SFA) intake. However, different SFA-rich foods may not have the same effects on cardiovascular risk factors. We compared full-fat yogurt with low-fat yogurt and butter for their effects on cardiometabolic risk factors in healthy individuals. Randomized, two-period crossover trial conducted from October 2022 to April 2023 among 30 healthy men and women (15 to receive full-fat yogurt first, and 15 to receive low-fat yogurt and butter first). Participants consumed a diet with 1.5-2 servings of full-fat (4%) yogurt or low-fat (< 1.5) yogurt and 10-15g of butter per day for 4 weeks, with 4 weeks wash-out when they consumed 1.5-2 servings of low-fat milk. At baseline, and the end of each 4 weeks, fasting blood samples were drawn and plasma lipids, glycemic and inflammatory markers as well as expression of some genes in the blood buffy coats fraction were determined. All 30 participants completed the two periods of the study. Apolipoprotein B was higher for the low-fat yogurt and butter [changes from baseline, + 10.06 (95%CI 4.64 to 15.47)] compared with the full-fat yogurt [-4.27 (95%CI, -11.78 to 3.23)] and the difference between two treatment periods was statistically significant (p = 0.004). Non-high-density lipoprotein increased for the low-fat yogurt and butter [change, + 5.06 (95%CI (-1.56 to 11.69) compared with the full-fat yogurt [change, - 4.90 (95%CI, -11.61 to 1.81), with no significant difference between two periods (p = 0.056). There were no between-period differences in other plasma lipid, insulin, and inflammatory biomarkers or leukocyte gene expression of ATP-binding cassette transporter 1 and CD36. This study suggests that short-term intake of SFAs from full-fat yogurt compared to intake from butter and low-fat yogurt has fewer adverse effects on plasma lipid profile. GOV: NCT05589350, 10/15/2022.

Saturated fatty acids differently affect mitochondrial function and the intestinal epithelial barrier depending on their chain length in the in vitro model of IPEC-J2 enterocytes.

Introduction: Maintenance of the intestinal barrier mainly relies on the mitochondrial function of intestinal epithelial cells that provide ATP through oxidative phosphorylation (OXPHOS). Dietary fatty acid overload might induce mitochondrial dysfunction of enterocytes and may increase intestinal permeability as indicated by previous in vitro studies with palmitic acid (C16:0). Yet the impact of other dietary saturated fatty acids remains poorly described. Methods: To address this question, the in vitro model of porcine enterocytes IPEC-J2 was treated for 3days with 250µM of lauric (C12:0), myristic (C14:0), palmitic (C16:0) or stearic (C18:0) acids. Results and discussion: Measurement of the transepithelial electrical resistance, reflecting tight junction integrity, revealed that only C16:0 and C18:0 increased epithelial permeability, without modifying the expression of genes encoding tight junction proteins. Bioenergetic measurements indicated that C16:0 and C18:0 were barely β-oxidized by IPEC-J2. However, they rather induced significant OXPHOS uncoupling and reduced ATP production compared to C12:0 and C14:0. These bioenergetic alterations were associated with elevated mitochondrial reactive oxygen species production and mitochondrial fission. Although C12:0 and C14:0 treatment induced significant lipid storage and enhanced fusion of the mitochondrial network, it only mildly decreased ATP production without altering epithelial barrier. These results point out that the longer chain fatty acids C16:0 and C18:0 increased intestinal permeability, contrary to C12:0 and C14:0. In addition, C16:0 and C18:0 induced an important energy deprivation, notably via increased proton leaks, mitochondrial remodeling, and elevated ROS production in enterocytes compared to C12:0 and C14:0.

Health behaviour in baby boomers and Generations X, Y, and Z: focus on dietary fibre and saturated fat intake

Purpose: To assess the frequency of food intake as a source of dietary fibre and saturated fatty acid intake in terms of preventive health care for women and men of the baby boomer (BB), X, Y, and Z generations. Design/methodology/approach: The research instrument was a survey questionnaire administered through the computer-assisted web interviewing (CAWI) method using Google Forms. The survey was conducted from February to March 2023. The survey included 204 respondents between the ages of 19 and 60, residents of Gdynia. Purposive group selection was used. The results of the survey are presented as the percentage distribution (percentage) of each evaluation (% of indications). A chi-square test with Yates correction was used to determine the effect of gender and age on lifestyle, dietary style and frequency of dietary fibre and saturated fatty acid intake in the study groups. Findings: Analysis of the consumption of selected food groups by respondents showed that gender and age influenced the lifestyle and type of selected food products consumed by adults, and therefore the attainment of individual nutrient requirements, and the risk of chronic non-communicable diseases. It is satisfactory that the level of fat intake among the surveyed group of respondents was at an appropriately low level. On the other hand, the inadequate and very low intake of dietary fibre among women and men remains a concern. Research limitations/implications: The research has certain limitations. The results obtained are not representative and cannot be generalised to the population of women and men of the baby boomer (BB), X, Y and Z generations in Poland. Practical implications: The present study is part of health risk management and health promotion in the Polish population. It is important that adults (in Poland) pay attention to the impact of the products they consume on their health, since the lack of a balanced diet and an excessive supply of simple carbohydrates and saturated fatty acids carries a risk of reducing their quality of life. It is essential to conduct research monitoring the dietary behaviour of various population groups to evaluate the need for preventive actions to ensure health and better safeguard the mental and physical condition of current and future generations. Social implications: The research is part of health risk management and health promotion in the Polish population. Originality/value: The research adds to the knowledge of adult eating behaviour from the perspective of the Sustainable Development Goals. Keywords: adult consumers, eating habits, health-related quality of life. Category of the paper: Research paper

Association between dietary intake of saturated fatty acid subgroups and breast cancer risk.

The impact of dietary saturated fatty acids (SFAs) on breast cancer risk may vary depending on their carbon chain lengths, attributable to the discrepancy in their dietary sources and biological activities. The associations between SFA subgroups classified by chain length and breast cancer risk remain controversial. In this case-control study, we aimed to investigate the association between the dietary intake of SFA subgroups, classified by chain lengths, and odds of breast cancer in China. This study included 1661 cases of breast cancer (confirmed as primary and histologically) and 1674 frequency-matched controls. Face-to-face interviews were used to collect basic information, while dietary intake information was obtained by a food frequency questionnaire. The unconditional logistic regression model was used to calculate the odds ratios (ORs) and 95% confidence intervals (95% CIs). All SFA subgroups were inversely associated with odds of breast cancer. The adjusted ORs (95% CIs) were 0.78 (0.61-0.99) for medium-chain SFAs, 0.50 (0.31-0.83) for long even-chain SFAs, 0.69 (0.54-0.88) for long odd-chain, and 0.67 (0.48-0.95) for very long-chain SFAs, respectively. In the restricted cubic spline (RCS) models, a non-linear M-shaped association was observed between long odd-chain SFAs and odds of breast cancer (Pnon-linearity = 0.007). However, the associations of medium-chain SFAs, long even-chain SFAs, and very long-chain SFAs did not reach statistical significance (Pnon-linearity > 0.05). No significant interactions were observed between all these four subgroups of SFAs and menopausal status or BMI. Our findings emphasize the significance of elucidating the associations of dietary SFAs according to chain lengths, providing insights into the etiology as well as the potential benefits of SFA-rich food intake in reducing the risk of breast cancer. Further prospective cohort studies and intervention studies are warranted to confirm these findings and identify the underlying mechanisms of the association between dietary SFAs and breast cancer.

Modulatory effects of dietary saturated fatty acids on platelet mitochondrial function following short-term exposure to ambient Particulate Matter (PM2.5)

ABSTRACT Exposure to ambient fine particulate matter (PM2.5) was found to produce vascular injury, possibly by activating platelets within days after exposure. The aim of this study was to investigate the modulatory effects of dietary saturated fatty acids on platelet mitochondrial respiratory parameters following short-term inhalational exposure to PM2.5. A total of 22 healthy male volunteers were recruited from the Research Triangle area of North Carolina. Platelets were isolated from fresh whole blood samples and mitochondrial respiratory parameters were measured using an extracellular flux analyzer. Intake of saturated fat was averaged from multiple 24-hr dietary recalls. Daily ambient PM2.5 concentrations were obtained from ambient air quality monitoring stations. Correlation and ANOVA were used in data analyses, along with the pick-a-point method and the Johnson-Neyman technique for probing moderation. After controlling for age and omega-3 index, the intake of dietary saturated fatty acids after reaching 9.3% or higher of the total caloric intake significantly moderated the associations between PM2.5 exposure and several platelet mitochondrial respiratory parameters. In conclusion, dietary saturated fatty acids above 9.3% of total caloric intake influenced the relationship between short-term PM2.5 exposure and platelet mitochondrial respiration. Further research is needed to understand these associations and their implications for cardiovascular health.

A prospective cohort study on the association between dietary fatty acids intake and risk of hypertension incident

There are inconclusive results available on the association between dietary fatty acid intake and the risk of hypertension (HTN) incident. In this study, we investigate the relationship between baseline dietary fatty acids intake including polyunsaturated fatty acid (PUFA), trans fatty acids (TFA), monounsaturated fatty acid (MUFA), and saturated fatty acid (SFA), and the risk of first incidence hypertension. The current prospective cohort study was carried out from the Ravansar Non-Communicable Diseases (RaNCD) cohort. A food frequency questionnaire (FFQ) with 118 items was used for the assessment of dietary data. Cox proportional hazards analyses were done to estimate hazard ratios (HR) and 95% confidence intervals (CIs) of the highest versus lowest quartile intake of SFA, PUFA, MUFA, and SFA and risk of HTN. Out of 7359 eligible participants, 597 new cases of HTN were identified over an average of 6.4 ± 1.33 years of follow-up. No significant relationship was observed between the fourth compared to the first categories of dietary SFA (HR: 0.82, 95% CI 0.55, 1.21; P trend: 0.476), MUFA (HR: 0.71, 95% CI 0.48, 1.06; P trend: 0.252), PUFA (HR: 0.86, 95% CI 0.62, 1.19; P trend: 0.315) and TFA (HR: 0.99, 95% CI 0.76, 1.27; P trend: 0.675), and risk of HTN. However, a significant inverse association between each 1 g per day increase in dietary MUFA intake during 6.4 years of follow up and HTN incident (HR: 0.97; 95% CI 0.94, 0.99; P 0.044) was observed. In brief, our study revealed that higher dietary MUFA intake was protectively associated with HTN incident. Dietary MUFA-rich foods should be encouraged to improve blood pressure.

Intake of palmitic acid and its association with metabolic flexibility in middle-aged individuals: a preliminary study

Objective This study aimed to assess the relationship between dietary palmitic acid (PA) intake and its association with body fat deposition and metabolic flexibility (MF) in middle-aged healthy individuals. Methods Fifteen healthy participants (n = 15; 6 males, 9 females) with a mean age of 54 were enlisted. They were subjected to graded exercise tests using a cycle ergometer coupled with a calorimeter. Respiratory gas exchange was evaluated to determine two MF parameters. First, the MF index was derived by multiplying peak fatty acid oxidation (PFO) per kg of fat-free mass (FFM) with the percentage of VO2max at PFO. The second parameter, peak energy substrates’ oxidation (aka PESO), was computed by aggregating the kilocalories from PFO and peak carbohydrate oxidation, normalized per kg FFM. Dietary intake was gauged using a 7-day dietary record. Spearman’s regression was employed to analyze the association between dietary intake of specific fat classes, PA, MF parameters, and body fat percentage. Results Preliminary results demonstrate that dietary saturated fatty acids (SFA) within physiological limits correlate with enhanced substrate oxidation capacity. This suggests augmented MF in middle-aged subjects. Among dietary SFA, PA was identified as the primary factor in this favorable correlation. Conclusions Our initial observations, even though preliminary, strongly suggest a beneficial association between PA intake, MF, and body fat percentage. This underscores the potential nutritional importance of PA in promoting MF. Significance Statement Disparities in data regarding the health effects of dietary fats may arise from the distinct roles various dietary fatty acids play in MF.

Abstract 12411: Fatty Acid Saturation Status in Murine High Fat Diets Modulates Platelet Reactivity

Introduction: We have recently shown that membrane fatty acids are key modulators of megakaryocyte differentiation and platelet formation. In obesity, patients have an altered plasma lipid composition, which coincides with enhanced platelet responsiveness to activation. However, the mechanism underlying this platelet phenotype remains unknown. Hypothesis: We hypothesized that the obese plasma lipidome alters the composition of the megakaryocyte membrane, which ultimately leads to the generation of hyper-reactive platelets. Aim: To investigate the impact of high fat diets with different fatty acid compositions on megakaryocyte development and platelet reactivity. Results: Mice were fed chow or high fat diets enriched in either saturated fatty acids (50% SFAs) or polyunsaturated fatty acids (50% PUFAs, omega-6-enriched). Neither high fat diet resulted in changes in megakaryocyte numbers, but both caused a significant increase in the size of bone marrow megakaryocytes, suggesting diet-derived lipid uptake into megakaryocytes. When examining platelet reactivity, we found that mice fed the SFA-enriched high fat diet exhibited increased expression of the active form of integrin αIIbβ3 (JON/A) in resting platelets and that both JON/A and P-selectin expression were significantly decreased after platelets were stimulated with ADP and the thromboxane A 2 analogue U46619. In contrast, platelets from mice fed the PUFA omega-6-enriched high fat diet had no differences in platelet reactivity compared to mice fed normal chow. Conclusions: Our data reveal that dietary fatty acid saturation status affects platelet reactivity, consistent with previous human studies showing variability in platelet reactivity in obese individuals. Further explorations will elucidate if plasma and/or platelet lipid content may be an indicator of risk for thrombosis or cardiovascular disease.

Dietary fat quality and serum androgen concentrations in middle-aged men

Background/ObjectivesAverage testosterone concentrations in men have declined over the last few decades. The reasons for this are not fully known, but changes in dietary fat quality have been suggested to have a role. This study aimed to investigate the associations of different dietary fatty acids with serum androgen concentrations.Subjects/MethodsA total of 2546 men with a mean age of 53 from the Kuopio Ischaemic Heart Disease Risk Factor Study were included in this cross-sectional study. Associations between dietary saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) and trans (TFA) fatty acids and concentrations of serum total and free testosterone and steroid hormone binding globulin (SHBG) were analyzed with analysis of covariance and linear regression analysis. Associations of isocaloric replacement of nutrients and androgen concentrations were analyzed with multivariate nutrient-density models.ResultsAfter adjustment for age, examination year and energy intake, higher SFA intake was associated with higher serum total and free testosterone and SHBG concentrations, and higher PUFA intake with lower concentrations. However, the associations were attenuated and not statistically significant after further adjustments for potential confounders. MUFA and TFA intakes were not associated with androgen concentrations. In isocaloric substitution models, replacing dietary protein with SFA was associated with higher serum total testosterone and SHBG concentrations. After excluding men with history of CVD or diabetes (n = 1021), no statistically significant associations were found.ConclusionsDietary fat quality was not independently associated with serum androgen concentrations in middle-aged men. However, replacing protein with SFA may be associated with higher serum androgen concentrations.

Dietary saturated fatty acids increased all-cause and cardiovascular disease mortality in an elderly population: The National Health and Nutrition Examination Survey

The influence of dietary saturated fatty acids intake on human health and cardiovascular disease (CVD) remains debated. The aim of this study was to explore the association between dietary saturated fatty acid consumption and all-cause and CVD mortality among the elderly population. Data for the participants in this study were obtained from the National Health and Nutrition Examination Survey dataset spanning the years 2003 through 2008. Information regarding mortality and the follow-up duration were extracted from the 2019 public-use linked mortality files provided by the National Center for Health Statistics. A total of 3404 participants were included in this study. The ratio of dietary saturated fatty acids to total fat was associated with the mortality from all-cause, heart disease, and cerebrovascular disease after adjusting confounding factors (P < .05). For every 10% increase in the saturated fatty acids to total fat ratio, all-cause mortality increased by 24% (hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.13–1.37), the heart disease mortality increased by 26% (HR, 1.26; 95% CI, 1.05–1.52), and the cerebrovascular disease mortality increased by 67% (HR, 1.67; 95% CI, 1.14–2.45) at 10 years’ follow-up. In addition, low dietary saturated fatty acids intake was associated with reduced mortality because of all-cause and heart disease after adjusting confounding factors (P < .05). In conclusion, in this elderly population, dietary saturated fatty acid intake was associated with all-cause mortality, heart disease mortality, and cerebrovascular disease mortality. Reducing saturated fatty acid intake in the diet may extend the survival rate for the elderly population. However, the difference of the effects of specific dietary saturated fatty acids with different chain lengths on mortality needs further study.

Association Between Dietary and Serum Cholesterol and Cognitive Function Among the U.S. Elderly from NHANES 2011-2014.

The association between dietary or serum cholesterol and cognitive performance in older adults has not been well-established. This study aimed to investigate the potential association between dietary or serum cholesterol and cognitive performance in the elderly population. A cross-sectional analysis was conducted using data from the National Health and Nutrition Examination Survey (NHANES) 2011-2012 and 2013-2014. Diet and supplement cholesterol was estimated based on two non-consecutive 24-hour dietary recalls. Cognitive function was assessed using various statistical tests. Poor cognitive performance was defined as scores below the lowest quartile within age groups. Regression models were adjusted for demographic factors, and subgroup analyses were performed for non-Hispanic White (NHW) and non-Hispanic Black (NHB) individuals. Among 759 participants aged 60 years and above, dietary cholesterol was only associated with dietary saturated fatty acids and serum high-density lipoprotein cholesterol. There was no evidence of an association between dietary cholesterol and cognitive function, except for NHB individuals, where dietary cholesterol showed a positive correlation with cognitive function. In the overall sample and NHW participants, there were consistent positive associations between serum total cholesterol and cognitive performance across statistical tests, while such associations were rare among NHB individuals. Although not statistically significant, NHB individuals had higher dietary/supplementary/total cholesterol intake compared with NHW individuals. Within the normal range, increasing serum cholesterol may be a potential factor to prevent or relieve cognitive dysfunction. However, ethnic differences should be taken into account when considering the association between cholesterol and cognitive performance.

Association of free-living diet composition with plasma lipoprotein(a) levels in healthy adults

BackgroundLipoprotein (a) [Lp(a)] is an apoB100-containing lipoprotein with high levels being positively associated with atherosclerotic cardiovascular disease. Lp(a) levels are genetically determined. However, previous studies report a negative association between Lp(a) and saturated fatty acid intake. Currently, apoB100 lowering therapies are used to lower Lp(a) levels, and apheresis therapy is FDA approved for patients with extreme elevations of Lp(a). The current study analyzed the association of free-living diet components with plasma Lp(a) levels.MethodsDietary composition data was collected during screening visits for enrollment in previously completed lipid and lipoprotein metabolism studies at Columbia University Irving Medical Center via a standardized protocol by registered dietitians using 24 hour recalls. Data were analyzed with the Nutrition Data System for Research (Version 2018). Diet quality was calculated using the Healthy Eating Index (HEI) score. Fasting plasma Lp(a) levels were measured via an isoform-independent ELISA and apo(a) isoforms were measured using gel electrophoresis.ResultsWe enrolled 28 subjects [Black (n = 18); Hispanic (n = 7); White (n = 3)]. The mean age was 48.3 ± 12.5 years with 17 males. Median level of Lp(a) was 79.9 nmol/L (34.4–146.0) and it was negatively associated with absolute (grams/day) and relative (percent of total calories) intake of dietary saturated fatty acids (SFA) (R = -0.43, P = 0.02, SFA …(% CAL): R = -0.38, P = 0.04), palmitic acid intake (R = -0.38, P = 0.05), and stearic acid intake (R = -0.40, P = 0.03). Analyses of associations with HEI score when stratified based on Lp(a) levels > or ≤ 100 nmol/L revealed no significant associations with any of the constituent factors.ConclusionsUsing 24 hour recall, we confirm previous findings that Lp(a) levels are negatively associated with dietary saturated fatty acid intake. Additionally, Lp(a) levels are not related to diet quality, as assessed by the HEI score. The mechanisms underlying the relationship of SFA with Lp(a) require further investigation.

Lipid remodeling in megakaryocyte differentiation and platelet biogenesis.

Lipid remodeling, from fatty acid transport and de novo lipid synthesis, is necessary for megakaryocyte differentiation and platelet production. Dietary saturated fatty acids, impaired fatty acid transport and/or dysfunction in lipid biogenesis can contribute to low platelet counts.

The interplay between dietary fatty acids and gut microbiota influences host metabolism and hepatic steatosis

Dietary lipids can affect metabolic health through gut microbiota-mediated mechanisms, but the influence of lipid-microbiota interaction on liver steatosis is largely unknown. We investigate the impact of dietary lipids on human gut microbiota composition and the effects of microbiota-lipid interactions on steatosis in male mice. In humans, low intake of saturated fatty acids (SFA) is associated with increased microbial diversity independent of fiber intake. In mice, poorly absorbed dietary long-chain SFA, particularly stearic acid, induce a shift in bile acid profile and improved metabolism and steatosis. These benefits are dependent on the gut microbiota, as they are transmitted by microbial transfer. Diets enriched in polyunsaturated fatty acids are protective against steatosis but have minor influence on the microbiota. In summary, we find that diets enriched in poorly absorbed long-chain SFA modulate gut microbiota profiles independent of fiber intake, and this interaction is relevant to improve metabolism and decrease liver steatosis.

Immediate-release niacin and a monounsaturated fatty acid-rich meal on postprandial inflammation and monocyte characteristics in men with metabolic syndrome

When considered separately, long-term immediate-release niacin and fatty meals enriched in monounsaturated fatty acids (MUFA) decrease postprandial triglycerides, but their effects on postprandial inflammation, which is common in individuals with metabolic syndrome, are less known. Moreover, successful combination is lacking and its impact on acute disorders of the innate immune cells in the metabolic syndrome remains unclear. Here, we aimed to establish the effects from combination with niacin of different fats [butter, enriched in saturated fatty acids (SFA), olive oil, enriched in MUFA, and olive oil supplemented with eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids] on plasma inflammatory markers and circulating monocyte subsets, activation and priming at the postprandial period in individuals with metabolic syndrome. A random-order within-subject crossover experiment was performed, in which 16 individuals with metabolic syndrome and 16 age-matched healthy volunteers took 2g immediate-release niacin together with the corresponding fatty meal or a meal with no fat as control. In total, 128 postprandial curves were analysed. We sampled hourly over 6h for plasma concentrations of soluble inflammatory markers and triglycerides. Circulating monocyte subsets (CD14/CD16 balance), activation (CCL2/CCR2 axis) and priming (M1/M2-like phenotype) at the time of postprandial hypertriglyceridemic peak were also addressed. Dietary SFA (combined with niacin) promote postprandial excursions of circulating IL-6, IL-1β, TNF-α and CD14/CCR2-rich monocytes with a pro-inflammatory M1-like phenotype, particularly in individuals with metabolic syndrome. In contrast, dietary MUFA (combined with niacin) postprandially increased circulating CD16-rich monocytes with an anti-inflammatory M2-like phenotype. Omega-3 PUFA did not add to the effects of MUFA. The co-administration of a single-dose of immediate-release niacin with a fatty meal rich in MUFA, in contrast to SFA, suppresses postprandial inflammation at the levels of both secretory profile and monocyte response in individuals with metabolic syndrome. These findings highlight a potential role of combining niacin and dietary MUFA for the homeostatic control of inflammation and the innate immune system, identifying a new search direction for the management of disorders associated with the metabolic syndrome.

Stearic Acid, but not Palmitic Acid, is Associated with Inflammatory and Endothelial Dysfunction Biomarkers in Individuals at Cardiovascular Risk.

Several studies have associated dietary saturated fatty acids (SFAs) with cardiovascular risk but there are still many controversies. Most of these studies have focused on the effects of palmitic acid on circulating lipids. Stearic acid usually shows a neutral effect on blood lipids, however, there is a lack of clinical studies assessing the link with inflammatory and endothelial dysfunction markers. To evaluate the association of red blood cell (RBC) SFA (palmitic and stearic acids) with circulating inflammatory and endothelial dysfunction biomarkers. Cross-sectional study of 79 adults of both sexes with at least one cardiovascular risk factor but without previous events (acute myocardial infarction or stroke). Plasma biomarkers - lipids, glucometabolic markers, high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), interleukin-10 (IL-10), monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor-α (TNF-α) - and RBC palmitic and stearic fatty acids were analyzed. The associations were assessed by correlation and multiple linear regression analyses, with statistical significance set at p < 0.05. Palmitic acid showed no significant associations with traditional cardiovascular risk factors or inflammatory markers. Stearic acid, on the other hand, was inversely correlated with blood cholesterol and triglycerides, but independently associated with hs-CRP, IL-6, and TNF-α. Stearic acid is associated with inflammatory and endothelial dysfunction biomarkers in individuals with at least one cardiovascular risk factor.

Impact of saturated compared with unsaturated dietary fat on insulin sensitivity, pancreatic β-cell function and glucose tolerance: a systematic review and meta-analysis of randomized, controlled trials

BackgroundThe impact of the dietary fat type on type 2 diabetes (T2D) remains unclear. ObjectivesWe aimed to evaluate the effects of replacing dietary saturated fatty acids (SFA) with mono- or poly-unsaturated fatty acids (MUFA and PUFA, respectively) on insulin sensitivity, pancreatic β-cell function, and glucose tolerance, as surrogate endpoints for T2D. MethodsWe conducted a systematic review and meta-analysis of randomized controlled trials that replaced ≥5% of total energy intake provided by SFA with MUFA or PUFA and reported indexes of insulin sensitivity, β-cell function, and/or glucose tolerance. We searched MEDLINE, Scopus, and the Cochrane Library (CENTRAL) up to 9 January, 2023. Eligible interventions had to be isocaloric, with no significant difference in other macronutrients. Data were synthesized using random-effects model meta-analysis. ResultsOf 6355 records identified, 10 parallel and 20 crossover trials with 1586 participants were included. The mean age of the participants was 42 years, 47% were male, mean body mass index (BMI; in kg/m2) was 26.8, median baseline fasting glucose was 5.13 mmol/L, and the median duration of interventions was 5 weeks. Replacing SFA with MUFA or PUFA had no significant effects on insulin sensitivity [standardized mean difference (SMD) SFA compared with MUFA: 0.01, 95% confidence interval (CI): −0.06 to 0.09, I2 = 0% and SMD SFA compared with PUFA: 0, 95% CI: −0.15 to 0.14, I2 = 0%]. Replacing SFA with MUFA did not significantly impact the β-cell function, evaluated by the disposition index (mean difference: −12, 95% CI: −158 to 133, I2=0%). Evidence on glucose tolerance (SFA compared with MUFA or PUFA) and on β-cell function when SFA were replaced with PUFA was scant. ConclusionsShort-term substitution of saturated with unsaturated fat does not significantly affect insulin sensitivity nor β-cell function (the latter in the SFA compared with MUFA comparison). Future studies are needed to elucidate longer term effects of dietary fat saturation on glucose homeostasis. This trial was registered at PROSPERO as CRD42020178382.