Intake Of Specific Fatty Acids Research Articles

Macronutrient intake modulates impact of EcoRI polymorphism of ApoB gene on lipid profile and inflammatory markers in patients with type 2 diabetes

We sought to examine whether dietary intakes may affect the relationship between ApoB EcoRI and lipid profile, as well as serum inflammatory markers, in patients with type 2 diabetes (T2DM). This current study consisted of 648 diabetic patients. Dietary intake was calculated by a food frequency questionnaire. Biochemical markers (high-density lipoprotein (HDL), total cholesterol (TC), LDL, TG, CRP, IL-18, PGF2α) were measured based on standard protocols. Genotyping of the Apo-B polymorphisms (rs1042031) was conducted by the PCR–RFLP method. The gene-diet interactions were evaluated using GLMs. In comparison to GG homozygotes, A-allele carriers with above the median -CHO intake (≥ 54 percent of total energy) had considerably greater TC and PGF2a concentrations. Furthermore, as compared to GG homozygotes, A-allele carriers with above the median protein intake (≥ 14 percent of total energy) had higher serum levels of TG (P = 0.001), CRP (P = 0.02), TG/HDL (P = 0.005), and LDL/HDL (P = 0.04) ratios. Moreover, A-allele carriers with above the median total fat intake (≥ 35 percent of total calories) had significantly higher TC level (P = 0.04) and LDL/HDL (P = 0.04) ratios compared to GG homozygotes. Furthermore, when compared to GG homozygotes, A-allele carriers who consumed above the median cholesterol (> 196 mg) had greater TG (P = 0.04), TG/HDL (P = 0.01) ratio, and IL-18 (P = 0.02). Furthermore, diabetic patients with the GA, AA genotype who consume above the median cholesterol had lower ghrelin levels (P = 0.01). In terms of LDL/HDL ratio, ApoB EcoRI and dietary intakes of specific fatty acids (≥ 9 percent for SFA and ≥ 12 percent for MUFA) had significant interaction. LDL/HDL ratio is greater in A-allele carriers with above the median SFA intake (P = 0.04), also when they consumed above the median MUFA this association was inverse (P = 0.04). Our study showed that plasma lipid levels in participants carrying the (AA or AG) genotype were found to be more responsive to increasing the percentage of energy derived from dietary fat, CHO, protein, SFA, and cholesterol consumption. Therefore, patients with a higher genetic susceptibility (AA or AG) seemed to have greater metabolic markers with a higher percentage of macronutrient consumption. Also, ApoB EcoRI correlations with metabolic markers might be attenuated with above the median MUFA consumption.

Fish Oil Nanoemulsion Supplementation Attenuates Bleomycin-Induced Pulmonary Fibrosis BALB/c Mice.

Diets rich in omega-3 or -6 fatty acids will produce different profiles for cell membranes phospholipid constitutions. Omegas 3 and 6 are part of the diet and can modulate the inflammatory profile. We evaluated the effects of the oral absorption of fish oil, when associated with a lipid nanoemulsion in an experimental pulmonary inflammatory model. Pulmonary fibrosis is a disease associated with excessive extracellular matrix deposition. We determined to investigate the morphophysiological mechanisms in mice that were pretreated after induction with bleomycin (BLM). The pretreatment was for 21 days with saline solution, sunflower oil (SO), fish oil (FO), and fish oil nanoemulsion (NEW3). The animals received a daily dose of 50 mg/Kg of docosahexaenoic acid DHA and 10 mg/Kg eicosapentaenoic (EPA) (100 mg/Kg), represented by a daily dose of 40 µL of NEW3. The blank group was treated with the same amount daily (40 µL) during the 21 days of pretreatment. The animals were treated with SO and FO, 100 mg/Kg (containing 58 mg/Kg of polyunsaturated fats/higher% linoleic acid) and 100 mg/Kg (50 mg/Kg of DHA and 10 mg/Kg EPA), respectively. A single dose of 5 mg/mL (50 μL) bleomycin sulfate, by the intratracheal surgical method in BALB/cAnNTac (BALB/c). NEW3 significantly reduced fibrotic progression, which can be evidenced by the protection from loss of body mass, increase in respiratory incursions per minute, decreased spacing of alveolar septa, decreased severity of fibrosis, and changes in the respiratory system. NEW3 attenuated the inflammatory changes developed in the experimental model of pulmonary fibrosis, while group SO showed a significant increase in inflammatory changes. This concluded that the presented results demonstrated that is possible to positively modulate the immune and inflamamtory response to an external agressor, by changing the nutitional intake of specific fatty acids, such as omega-3 placed in fish oil. Moreover, these benefits can be improved by the nanoencapsulation of fish oil in lipid nanoemulsions.

The Role of Dietary and Microbial Fatty Acids in the Control of Inflammation in Neonatal Piglets.

Simple SummaryThe maturation of the gut is a specific and very dynamic process in new-born piglets. Consequently, piglet’s gut is very susceptible to disturbances, especially in stressful periods of life, such as weaning, when the gut lining often becomes inflamed and leaky. Dietary fatty acids (FA) do not only serve as source of energy and essential FA, but they are important precursors for bioactive lipid mediators, which modulate inflammatory signalling in the body. The current review summarizes results on dietary sources of FA for piglets, the signalling cascades, bioactivities, the necessity to consider the autoxidation potential of polyunsaturated FA and the area of microbially produced long-chain FA. That said, porcine milk is high in fat, whereby the milk FA composition partly depends on the dietary FA composition of the sow. Therefore, manipulation of the sow diet is an efficient tool to increase the piglet’s intake of specific FA, e.g., n-3 polyunsaturated FA which show anti-inflammatory activity and may support intestinal integrity and functioning in the growing animal.Excessive inflammation and a reduced gut mucosal barrier are major causes for gut dysfunction in piglets. The fatty acid (FA) composition of the membrane lipids is crucial for mediating inflammatory signalling and is largely determined by their dietary intake. Porcine colostrum and milk are the major sources of fat in neonatal piglets. Both are rich in fat, demonstrating the dependence of the young metabolism from fat and providing the young organism with the optimum profile of lipids for growth and development. The manipulation of sow’s dietary polyunsaturated FA (PUFA) intake has been shown to be an efficient strategy to increase the transfer of specific FAs to the piglet for incorporation in enteric tissues and cell membranes. n-3 PUFAs, especially seems to be beneficial for the immune response and gut epithelial barrier function, supporting the piglet’s enteric defences in situations of increased stress such as weaning. Little is known about microbial lipid mediators and their role in gut barrier function and inhibition of inflammation in neonatal piglets. The present review summarizes the current knowledge of lipid nutrition in new-born piglets, comparing the FA ingestion from milk and plant-based lipid sources and touching the areas of host lipid signalling, inflammatory signalling and microbially derived FAs.

Fat intake pattern in women with polycystic ovary syndrome

Research questionDo women with polycystic ovary syndrome (PCOS) have a different fat intake pattern to women without PCOS? DesignCase–control study of 276 women between 20 and 35 years old from the Murcia region of Spain. Cases (n = 121) attended the Department of Gynaecology and Obstetrics of the University Clinical Hospital and were diagnosed with PCOS using Rotterdam criteria. Controls (n = 155) were women without PCOS attending the gynaecological outpatient clinic for routine gynaecological examinations. Data from clinical, gynaecological and analytical examinations were collected, including a food frequency questionnaire. Associations between fat intake and presence of PCOS and its phenotypes were examined using multiple logistic regression, adjusting for potential confounding factors. ResultsAlthough no association was found between fatty acid intake and PCOS, significant associations were observed for some PCOS phenotypes. The PCOS phenotype characterized by hyperandrogenism + oligo/amenorrhoea + polycystic ovarian morphology (‘H+O+POM’) was significantly associated with a higher intake of polyunsaturated fat (odds ratio [OR] 4.0; 95% confidence interval [CI] 1.1–14.2; fourth quartile of highest intake [Q4] versus lowest intake quartile as reference [Q1]) and omega-6 fatty acids (OR 3.5; 95% CI 1.01–12.4; Q3 versus Q1). The ‘H+O’ phenotype was positively associated with saturated fat intake (OR 6.9; 95% CI 1.1–41.6; Q4 versus Q1). ConclusionThis exploratory study suggests that higher intakes of specific fatty acids are related to some PCOS phenotypes although no association was found for PCOS on a global basis. It is recommended that studies with larger sample size be performed to further explore these associations, thus contributing to establishing recommendations about fat intake adapted to different PCOS phenotypes.

Dietary intake of fatty acids and risk of pancreatic cancer: Golestan cohort study

BackgroundAs pancreatic cancer (PC) is a malignancy with poor prognosis, finding strategies for its prevention became a notable priority. Among all the factors influencing the risk of PC, dietary items especially fats are considered as the most modifiable risk factors.This study is designed to assess the associations of dietary intake of fatty acids with the risk of PC incidence.MethodsA total of 50,045 adults between 40 and 75 years old participated in this cohort study in 2004–2008 and were followed up to the present. Intakes of fatty acids was evaluated by validated food-frequency questionnaire (FFQ). Cox proportional hazards regression model was used to estimate hazard ratio (HR) with 95 % confidence interval of differing levels of dietary intakes of fatty acids for incidence of PC.ResultsAt the end of follow-up period, 76 cases of PC were identified and 46,904 participants without history of cancer, acute kidney disorders, fibrosis and cirrhosis were included in the study. Dietary total saturated fatty acids (SFAS) was associated with PC risk (HR = 1.05 (1.01–1.09), Ptrend=0.01), whereas dietary total monounsaturated fatty acids (MUFAS) was inversely associated with the risk of PC (HR = 0.92 (0.86–0.99), Ptrend=0.04). Dietary total polyunsaturated fatty acids (PUFAS) did show a protective but not significant association with the risk of PC (HR = 0.91(0.84-1.00), Ptrend=0.05).ConclusionsThe amount of total fat intake is not a risk factor for PC in our study and focusing on the intake of specific fatty acids becomes more striking. Unsaturated fatty acids including PUFAS and especially MUFAS are considered as protective dietary factors in PC prevention. In contrast, total SFAS is positively associated with the increased risk of PC. However, very long chain and odd-chain saturated fatty acids intake may be protective against PC.

Issue Highlights

Issue Highlights

High Dietary Intake of Specific Fatty Acids Increases Risk of Flares in Patients With Ulcerative Colitis in Remission During Treatment With Aminosalicylates.

Dietary factors may have a significant role in relapse of disease among patients with ulcerative colitis (UC). However, the relationship between diet and UC is inadequately understood. We analyzed data from the diet's role in exacerbations of mesalamine maintenance study to determine whether dietary factors affect the risk of disease flares in patients with UC. We performed a prospective, multicenter, observational study of 412 patients, from 25 sites, with UC in remission during monotherapy with an aminosalicylate. Patients completed a validated food frequency questionnaire at enrollment and were followed for 12 months. We analyzed the relationship between diet and disease remission or flare for groups of macronutrients and micronutrients, and food groups previously associated with an increased risk of flare. Forty-five patients (11%) had a UC relapse within 1 year of study enrollment. When analyzed in tertiles, increasing intake of multiple fatty acids was associated with increasing odds of relapse. In multivariable logistic regression analysis, only myristic acid (odds ratio, 3.01; 95% confidence interval, 1.17-7.74) maintained this dose-response relationship. Other foods previously implicated in flares of UC, such as processed meat, alcohol, and foods high in sulfur, were not associated with an increased risk of flare. In a prospective study of more than 400 patients with UC undergoing treatment with aminosalicylates, we associated high dietary intake of specific fatty acids, including myristic acid (commonly found in palm oil, coconut oil, and dairy fats) with an increased risk of flare. These findings can help design interventional studies to evaluate dietary factors in UC.

Endogenous Production of Long-Chain Polyunsaturated Fatty Acids and Metabolic Disease Risk.

Long chain polyunsaturated fatty acids (PUFAs) are important structural components of cellular membranes and are converted into eicosanoids which serve various biological roles. The most common dietary n-6 and n-3 PUFAs are linoleic acid and α-linoleic acid, respectively. These 18-carbon chain fatty acids undergo a series of desaturation and elongation steps to become the 20-carbon fatty acids arachidonic acid and eicosapentaenoic acid, respectively. Evidence from genome wide association studies has consistently demonstrated that plasma and tissue levels of the n-6 long-chain PUFA arachidonic acid and to a lesser extent the n-3 long-chain PUFA eicosapentaenoic acid, are strongly influenced by variation in fatty acid desaturase-1,-2, and elongation of very long chain fatty acid genes. Studies of functional variants in these genes, as well as studies in which desaturase activity has been indirectly estimated by fatty acid product-to -precursor ratios, have suggested that endogenous capacity to synthesize long-chain PUFAs may be associated with metabolic diseases such as diabetes mellitus. Interventional studies are starting to tease out the complicated relationship between dietary intakes of specific fatty acids, variation in desaturase and elongase genes and tissue levels of long chain PUFAs. Thus future studies of dietary PUFA interventions designed to reduce inflammatory and metabolic diseases will need to carefully consider how an individual's genetically-determined endogenous long-chain PUFA synthesis capacity might modify therapeutic response.

Complement C3 Is Inversely Associated with Habitual Intake of Provitamin A but Not with Dietary Fat, Fatty Acids, or Vitamin E in Middle-Aged to Older White Adults and Positively Associated with Intake of Retinol in Middle-Aged to Older White Women1–3

Complement factor 3 (C3) has been identified as a novel risk factor for obesity-associated cardiometabolic diseases. Data in the literature suggest that C3 concentrations may be influenced by diet. Therefore, we investigated the associations of intake of total fat, specific fatty acids, and fat-soluble vitamin E (and individual tocopherols) and vitamin A (and its dietary precursors) with circulating C3. In a white cohort [Cohort on Diabetes and Atherosclerosis Maastricht (CODAM); n = 501; 59.4 ± 7.1 y; 61% men], associations of habitual nutrient intake (assessed by a food-frequency questionnaire) with circulating C3 were evaluated by using cross-sectional multiple linear regression analyses. Adjustments were first performed for age, sex, glucose metabolism status (i.e., impaired glucose metabolism or type 2 diabetes), and energy intake and subsequently for BMI, waist circumference, alcohol intake, smoking behavior, and season of blood collection. No associations with C3 were observed for total dietary fat intake or intake of specific fatty acids [saturated, monounsaturated, polyunsaturated, n–6 (ω-6), and n–3 (ω- 3) fatty acids], vitamin E, or individual tocopherols. We observed an inverse association with intake of provitamin A carotenoids α-carotene (in μg/d; regression coefficient β = −0.075; 95% CI: −0.140, −0.010; P = 0.025) and β-carotene (in μg/d; β = −0.021; 95% CI: −0.044, 0.002; P = 0.068) with C3 (in mg/L). In contrast, and only in women, dietary retinol intake (in μg/d) was positively associated with C3 (β = 0.116; 95% CI: 0.014, 0.218; P = 0.026; n = 196). In conclusion, these data suggest that fasting concentrations of C3 may, in a complex manner, be modifiable by variation in dietary provitamin A carotenoids and/or retinol content of the usual diet but most likely not by variations in fat composition and vitamin E content.

Intake of specific fatty acids and fat alters growth, health, and titers following vaccination in dairy calves

Typical fatty acid profiles of milk and milk replacer (MR) differ. Calf MR in the United States are made from animal fat, which are low in short- and medium-chain fatty acids and linolenic acid. Two 56-d trials compared a control MR containing 27% crude protein and formulated with 3 fat and fatty acid compositions. The 3 MR treatments were (1) only animal fat totaling 17% fat (CON), (2) animal fat supplemented with butyrate, medium-chain fatty acids, and linolenic acid using a commercial product (1.25% NeoTec4 MR; Provimi North America, Brookville, OH) totaling 17% fat (fatty acid–supplemented; FA-S), and (3) milk fat totaling 33% fat (MF). The MR were fed at 660g of dry matter from d 0 to 42 and weaned. Starter (20% crude protein) and water were fed ad libitum for 56d. Trial 1 utilized Holstein calves (24 female, 24 male) during summer months and trial 2 utilized Holstein calves (48 male) during fall months. Calves (41±1kg of initial body weight; 2 to 3d of age) were sourced from a single farm and housed in a naturally ventilated nursery without added heat. Calves were in individual pens with straw bedding. Calf was the experimental unit. Data for each trial were analyzed as a completely randomized design with a 3 (MR treatment) × 2 (sex) factorial arrangement of treatments in trial 1 with repeated measures and as a completely randomized design with 3 MR treatments in trial 2 with repeated measures. Preplanned contrast statements of treatments CON versus FA-S and CON versus MF were used to separate means. We found no interactions of MR treatment by sex. Calf average daily gain, hip width change, and feed efficiency differed (CON<FA-S; CON<MF). Days with abnormal fecal scores differed (CON>FA-S). Titers to bovine respiratory parainfluenza-3 and bovine virus diarrhea type 1 (vaccinations to these pathogens were on d 7 and 28) in serum samples taken on d 49 and 56 differed (CON<FA-S). Average and daily maximum skin tail temperatures based on automated measurements taken every 10min differed (CON>FA-S; CON<MF). Concentrations of urea nitrogen and glucose in serum samples taken on d 7, 21, and 28 differed (CON>FA-S; CON>MF). Calves fed FA-S and MF had improved growth and feed efficiency compared with calves fed CON, whereas calves fed FA-S also had improved measurements related to health and immunity.

Dietary Intake of Specific Fatty Acids and Breast Cancer Risk Among Postmenopausal Women in the VITAL Cohort

Studies of dietary fat intake and breast cancer have been inconsistent and few have examined specific fatty acids. We examined the association between specific monounsaturated (MUFA), polyunsaturated (PUFA), saturated (SFA), and trans-fatty acids (TFA) and breast cancer risk. Participants, 50–76 yr, were female members of the VITamins And Lifestyle (VITAL) Cohort, who were postmenopausal at baseline. In 2000–2002, participants completed a food frequency questionnaire. Seven hundred seventy-two incident, primary breast cancer cases were identified using a population-based cancer registry. Cox proportional hazard models estimated hazard ratios (HR) and 95% confidence intervals (95% CI) for the association between fatty acid intake and breast cancer risk. Intake of total MUFAs (highest vs. lowest quintile: HR = 1.61, 95% CI: 1.08–2.38, P trend = 0.02), particularly myristoleic and erucic acids, was associated with increased breast cancer risk. Whereas total SFA was suggestive of an increased risk (HR = 1.47, 95% CI: 1.00–2.15, P trend = 0.09), strong associations were observed for palmitic, margaric, and stearic acids. Total TFA and PUFA intake were not associated with breast cancer. However, among TFAs, linolelaidic acid was positively associated with risk; among PUFAs, intake of eicosapentaenoic and docosahexaenoic acids were inversely associated with risk. Our findings show that fatty acids are heterogeneous in their association with postmenopausal breast cancer risk.

Fatty Acid Consumption and Metabolic Syndrome Components: The GOCADAN Study

Fatty acids (FAs) have been related to changes in glucose and lipid metabolism. In this article, the authors assess the association between intake of specific FAs and components of the metabolic syndrome (MS) in adult Eskimos. A total of 691 Inupiat Eskimos (325 men and 366 women), aged 34 to 75 years, were examined as part of the Genetics of Coronary Artery Disease in Alaska Natives (GOCADAN) study. The investigation included a physical examination, blood pressure measurements, blood sampling under fasting conditions, 2-hour oral glucose tolerance test, and a personal interview including a validated food frequency questionnaire. Components of MS were defined according to the Third Report of the National Cholesterol Education Program Adult Treatment Panel criteria. Consumption of individual FAs showed associations with MS components. Long-chain omega-3 FAs, from fish and sea mammals, were associated with lower blood pressure, serum triglycerides, and 2-hour glucose and higher high-density lipoprotein cholesterol, fasting insulin, and homeostasis model assessment. Saturated fat consumption was associated with higher triglyceride levels and blood pressure. Trans-FA consumption was associated with higher blood pressure. Consumption of long-chain omega-3 FAs from marine sources may improve certain MS components, and thus may reduce risk for cardiovascular disease. High consumption of saturated FAs and trans-FAs may have an adverse effect on MS.

Validation of a FFQ to estimate the intake of PUFA using plasma phospholipid fatty acids and weighed foods records

Due to the growing knowledge about the role of specific fatty acids in health and disease, dietary intake measurements of individual fatty acids or classes of fatty acids are becoming increasingly important. The objective of this study was to evaluate the ability of the Nambour FFQ to estimate intakes of specific fatty acids, particularly PUFA. The study population was a sub-sample of adult participants in a randomised controlled trial of beta-carotene and sunscreen in the prevention of skin cancer (n 43). Dietary intake was assessed by a self-administered FFQ and a weighed food record (WFR). Non-fasting blood samples were collected and analysed for plasma phospholipid fatty acids. Median intakes on the FFQ were generally higher than the WFR except for the n-3 PUFA groups, where the FFQ estimated higher intakes. Correlations between the FFQ and WFR were moderate (r 0 x 32-0 x 59) except for trans fatty acids (r 0 x 03). Correlations between each of the dietary assessment methods and the plasma phospholipids were poor for all fatty acids other than the PUFA. Using the methods of triads approach, the FFQ validity coefficients for total n-3 fatty acids, total long chain n-3 fatty acids, EPA, arachidonic acid, docosapentaenoic acid and DHA were 0 x 50, 0 x 63, 0 x 45 and 0 x 62 and 0 x 62, respectively. For most fatty acids, the FFQ adequately estimates group mean fatty acid intakes and can adequately rank individuals; however, the ability of this FFQ to estimate trans fatty acids was poor.

Validation of a food frequency questionnaire measurement of selected nutrients using biological markers in African-American men

To validate selected nutrients assessed by the food frequency questionnaire (FFQ) used in the Harvard cohort studies in an African-American group. Blood aliquots were pooled for each decile of intake of two carotenoids and alpha tocopherol as measured by FFQ. These pooled samples were analyzed for nutrient content, and the resultant blood levels were plotted against the median for each decile of intake. In addition, adipose tissue samples taken from each man were analyzed for content of specific fatty acids. We calculated the Spearman correlations comparing intakes of specific fatty acids as percent of total fat intake, adjusted for energy intake, as measured by FFQ, with the percentage of the corresponding fatty acid in adipose tissue. African-American men (N=104) with prostate cancer were recruited from a Detroit physician's practice and completed a detailed FFQ. Comparing decile 10 with decile 1 intake of nutrients as measured by FFQ, there was a 32% higher blood level of lycopene, a 288% higher blood level of beta carotene and a 100% higher blood level of alpha tocopherol. The Spearman correlation coefficients between intakes of linoleic acid, alpha linolenic acid, long-chain n-3 fatty acids and trans fatty acid measured by FFQ and the corresponding adipose tissue levels were between 0.10 and 0.47. The FFQ was able to distinguish meaningful differences in biochemical measurements of selected nutrients and presumably corresponding differences in the extremes of intake in African-American men with prostate cancer who were likely to be motivated to report accurately. However, the results found are similar to those found in other populations.

Dietary fat intake in healthy adolescents: inverse relationships between the estimated intake of saturated fatty acids and serum cholesterol.

The objective of the present study was to describe the intake of dietary fatty acids among healthy 15-year-old boys and girls and to relate the intake of specific fatty acids and the fatty acid composition of the serum cholesterol esters to serum lipid, apolipoprotein (Apo) and insulin concentrations respectively. Fifty-two girls and forty-two boys were randomly selected from the official population register. Unexpectedly, significant inverse associations were found between the dietary content of saturated fatty acids with a chain length of four to fifteen C atoms, mainly derived from milk fat, as well as the corresponding fatty acids in the serum cholesterol esters, on the one hand and the serum concentrations of cholesterol and ApoB on the other. The estimated dietary intake of 4:0-10:0, 12:0 and 14:0 respectively, were all significantly inversely related to the serum cholesterol (r -0.32, r -0.31, r -0.30, all and ApoB (r -0.42, r -0.42, and r -0.40, all concentrations in girls and 12:0 to the ApoB concentration (r -0.55, in boys. The proportions of 12:0 and 15:0 in the serum cholesterol esters were negatively correlated with the serum cholesterol concentrations in both girls (r -0.34, r -0.32, and boys (r -0.53, r -0.32, and with the ApoB concentrations among boys (r -0.61, r -0.43, It is conceivable that milk fat contains or is associated with some component in the diet, or some other characteristics of the food intake, which counterbalances the expected positive relationships between saturated fat intake and lipid levels.

Tissue Specific Interactions of Exercise, Dietary Fatty Acids, and Vitamin E in Lipid Peroxidation

Both physical exercise and ingestion of polyunsaturated fatty acids that play an essential role in free radical-mediated damages cause lipid peroxidation. The intake of specific fatty acids can modulate the membrane susceptibility to lipid peroxidation. Data confirmed that liver, skeletal muscle, and heart have different capabilities to adapt their membrane composition to dietary fatty acids, the heart being the most resistant to changes. Such specificity affects membrane hydroperoxide levels that depend on the type of dietary fats and the rate of fatty acid incorporation into the membrane. Sedentary rats fed a monounsaturated fatty acid-rich diet (virgin olive oil) showed a higher protection of their mitochondrial membranes against peroxidation than sedentary rats fed a polyunsaturated fatty acid-rich diet (sunflower oil). Rats subjected to training showed higher hydroperoxide contents than sedentary animals, and exhaustive effort enhanced the aforementioned results as well as in vitro peroxidation with a free radical inducer. This study suggests that peroxide levels first depend on tissue, then on diet and lastly on exercise, both in liver and muscle but not in heart. Finally, it appears that α-tocopherol is a less relevant protective agent against lipid peroxidation than monounsaturated fatty acids.

Intake of fatty acids and risk of coronary heart disease in a cohort of Finnish men. The Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study.

The relation of intakes of specific fatty acids and the risk of coronary heart disease was examined in a cohort of 21,930 smoking men aged 50-69 years who were initially free of diagnosed cardiovascular disease. All men participated in the Finnish Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study and completed a detailed and validated dietary questionnaire at baseline. After 6.1 years of follow-up from 1985-1988, the authors documented 1,399 major coronary events and 635 coronary deaths. After controlling for age, supplement group, several coronary risk factors, total energy, and fiber intake, the authors observed a significant positive association between the intake of trans-fatty acids and the risk of coronary death. For men in the top quintile of trans-fatty acid intake (median = 6.2 g/day), the multivariate relative risk of coronary death was 1.39 (95% confidence interval (CI) 1.09-1.78) (p for trend = 0.004) as compared with men in the lowest quintile of intake (median = 1.3 g/day). The intake of omega-3 fatty acids from fish was also directly related to the risk of coronary death in the multivariate model adjusting also for trans-saturated and cis-monounsaturated fatty acids (relative risk (RR) = 1.30, 95% CI 1.01-1.67) (p for trend = 0.06 for men in the highest quintile of intake compared with the lowest). There was no association between intakes of saturated or cis-monounsaturated fatty acids, linoleic or linolenic acid, or dietary cholesterol and the risk of coronary deaths. All the associations were similar but somewhat weaker for all major coronary events.

Fatty Acid Composition of the Subcutaneous Adipose Tissue and Risk of Proliferative Benign Breast Disease and Breast Cancer

Studies in animals and geographic correlations across populations suggest that fatty acid intake may have a positive relationship with breast cancer risk, but analytic epidemiologic studies of fat intake have been less supportive. Adipose tissue analysis provides a more objective assessment of intakes of fatty acids that are not endogenously synthesized than do the questionnaire survey methods used in many epidemiologic studies. This case-control study of postmenopausal women was designed to examine the relationship between fatty acid composition of subcutaneous adipose tissue and risk of breast cancer and proliferative benign breast disease. In addition, we examined specific hypotheses that breast cancer risk is negatively associated with long-chain N-3 fatty acid intake, positively associated with trans fatty acid intake, and positively associated with increased intake of polyunsaturated fat together with low intake of antioxidants. Aspirates of subcutaneous fat from the buttocks were obtained from 380 women with newly diagnosed stage I or II breast cancer and 176 with proliferative benign breast disease. A total of 397 women who were evaluated for breast abnormalities at the same institutions but did not require breast biopsy or whose biopsy revealed nonproliferative benign breast disease served as the control group. We examined associations between saturated, monounsaturated, polyunsaturated, trans, or long-chain N-3 fatty acids and breast cancer, atypical hyperplasia, or proliferative benign breast disease without atypia. We observed no consistent patterns of association between breast cancer risk and any of the categories of fatty acids or the individual constituent fatty acids in the adipose tissue. Saturated fatty acids were inversely associated with risk of proliferative benign breast disease without atypia but not with atypical hyperplasia or breast cancer. This association was not observed, however, when total fat intake was taken into account. Women with high levels of polyunsaturated fatty acids in adipose tissue and low serum or dietary levels of antioxidants were not observed to be at higher risk of breast cancer. Using an objective measure of intake, we observed no major associations between polyunsaturated fatty acids, including long-chain N-3 fatty acids and trans fatty acids, and risk of breast cancer or proliferative benign breast disease. These data do not support the hypothesis that intake of specific fatty acids, particularly polyunsaturated and trans fatty acids, is an important risk factor for malignant or benign breast disease.

Practical aspects of achieving positive energy balance in low birth weight infants

For the low birth weight (LBW) infant, energy balance during the first several days of life usually is equated to absorption of sufficient energy to match energy expenditure. Most studies show that energy expenditure of nongrowing LBW infants is 45 to 55 kcal/kg/day. Hence, for energy equilibrium, energy intake minus energy losses (i.e., metabolizable energy intake) must be at least 50 kcal/kg/day. Intakes above this amount result in energy storage or positive energy balance, whereas lesser intakes necessitate mobilization of endogenous energy stores (negative energy balance). Some of the problems of achieving positive energy balance in LBW infants (e.g., feeding intolerance and fear of necrotizing enterocolitis) can be circumvented by use of parenterally delivered nutrients. On balance, virtually all LBW infants will tolerate parenteral amino acid, glucose, and lipid intakes, respectively, of 2, 5, and 1 gm/kg/day or an energy intake of about 40 kcal/kg/day. It usually is possible to increase energy intake of most infants by an additional 10 kcal/kg/day. Whether this is achieved with enterally delivered nutrients or additional parenteral glucose or lipid intake, including the necessary modifications to enhance tolerance (e.g., insulin, 20% vs 10% lipid emulsions, and lipid emulsions containing medium-chain fatty acids), must be decided for each infant based on his or her underlying condition, likelihood of tolerating either substrate, and the impact of intolerance on the underlying condition. The consequences of not providing an essential nutrient during the immediate postnatal period also must be considered. The fact that essential fatty acid deficiency develops more rapidly in infants receiving isocaloric (60 kcal/kg/day) parenteral intakes with versus without amino acids, the likelihood that brain growth continues despite negative energy balance, and the possibility that LBW infants may not be able to desaturate/elongate linoleic and linolenic acids to the more unsaturated, longer-chain fatty acids that are deposited in the developing brain suggest that these infants may require exogenous intakes of specific fatty acids.