Effects of supplementation with omega-3 on insulin sensitivity and non-esterified free fatty acid (NEFA) in type 2 diabetic patients

Omega-3 long-chain polyunsaturated fatty acids: Metabolism and health implications

Recently, omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) have gained substantial interest due to their specific structure and biological functions. Humans cannot naturally produce these fatty acids (FAs), making it crucial to obtain them from our diet. This comprehensive review details n-3 LC-PUFAs and their role in promoting and maintaining optimal health. The article thoroughly analyses several sources of n-3 LC-PUFAs and their respective bioavailability, covering marine, microbial and plant-based sources. Furthermore, we provide an in-depth analysis of the biological impacts of n-3 LC-PUFAs on health conditions, with particular emphasis on cardiovascular disease (CVD), gastrointestinal (GI) cancer, diabetes, depression, arthritis, and cognition. In addition, we highlight the significance of fortification and supplementation of n-3 LC-PUFAs in both functional foods and dietary supplements. Additionally, we conducted a detailed analysis of the several kinds of n-3 LC-PUFAs supplements currently available in the market, including an assessment of their recommended intake, safety, and effectiveness. The dietary guidelines associated with n-3 LC-PUFAs are also highlighted, focusing on the significance of maintaining a well-balanced intake of n-3 PUFAs to enhance health benefits. Lastly, we highlight future directions for further research in this area and their potential implications for public health.

Strategies for Therapeutic Amelioration of Aberrant Plasma Zn2+ Handling in Thrombotic Disease: Targeting Fatty Acid/Serum Albumin-Mediated Effects

The initiation, maintenance and regulation of blood coagulation is inexorably linked to the actions of Zn²⁺ in blood plasma. Zn²⁺ interacts with a variety of haemostatic proteins in the bloodstream including fibrinogen, histidine-rich glycoprotein (HRG) and high molecular weight kininogen (HMWK) to regulate haemostasis. The availability of Zn²⁺ to bind such proteins is controlled by human serum albumin (HSA), which binds 70–85% of plasma Zn²⁺ under basal conditions. HSA also binds and transports non-esterified fatty acids (NEFAs). Upon NEFA binding, there is a change in the structure of HSA which leads to a reduction in its affinity for Zn²⁺. This enables other plasma proteins to better compete for binding of Zn²⁺. In diseases where elevated plasma NEFA concentrations are a feature, such as obesity and diabetes, there is a concurrent increase in hypercoagulability. Evidence indicates that NEFA-induced perturbation of Zn²⁺-binding by HSA may contribute to the thrombotic complications frequently observed in these pathophysiological conditions. This review highlights potential interventions, both pharmaceutical and non-pharmaceutical that may be employed to combat this dysregulation. Lifestyle and dietary changes have been shown to reduce plasma NEFA concentrations. Furthermore, drugs that influence NEFA levels such as statins and fibrates may be useful in this context. In severely obese patients, more invasive therapies such as bariatric surgery may be useful. Finally, other potential treatments such as chelation therapies, use of cholesteryl transfer protein (CETP) inhibitors, lipase inhibitors, fatty acid inhibitors and other treatments are highlighted, which with additional research and appropriate clinical trials, could prove useful in the treatment and management of thrombotic disease through amelioration of plasma Zn²⁺ dysregulation in high-risk individuals.

Could nutrient supplements provide additional glycemic control in diabetes management? A systematic review and meta-analysis of randomized controlled trials of as an add-on nutritional supplementation therapy

This systematic review and meta-analysis assessed the antidiabetic effect of pharmaconutrients as an add-on in type 2 diabetes mellitus patients by pooling data from currently available randomized controlled trials (RCTs). Data sources included the PubMed and EMBASE, Cochrane Central Register of Controlled Trials. RCTs reporting changes in glycosylated hemoglobin (HbA1c), fasting blood glucose (FBG), or homeostasis model assessment of insulin resistance (HOMA-IR) levels following add-on pharmaconutritional therapies for T2DM patients consuming antidiabetic drugs were targeted. Using random-effects meta-analyses, we identified pharmaconutrients with effects on glycemic outcomes. Heterogeneity among studies was presented using I² values. Among 9537 articles, 119 RCTs with nine pharmaconutrients (chromium; coenzyme Q10; omega-3 fatty acids; vitamins C, D, and E; alpha-lipoic acid; selenium; and zinc) were included. Chromium (HbA1c, FBG, and HOMA-IR), coenzyme Q10 (HbA1c and FBG), vitamin C (HbA1c and FBG), and vitamin E (HbA1c and HOMA-IR) significantly improved glycemic control. Baseline HbA1c level and study duration influenced the effects of chromium and vitamin E on HbA1c level. Sensitivity analyses did not modify the pooled effects of pharmaconutrients on glycemic control. Administration of chromium, coenzyme Q10, and vitamins C and E for T2DM significantly improved glycemic control. This study has been registered in PROSPERO (CRD42018115229).

Plant polyphenols mechanisms of action on insulin resistance and against the loss of pancreatic beta cells

Diabetes mellitus describes a group of metabolic disorders characterized by a prolonged period hyperglycemia with long-lasting detrimental effects on the cardiovascular and nervous systems, kidney, vision, and immunity. Many plant polyphenols are shown to have beneficial activity for the prevention and treatment of diabetes, by different mechanisms. This review article is focused on synthesizing the mechanisms by which polyphenols decrease insulin resistance and inhibit loss of pancreatic islet β-cell mass and function. To achieve the objectives, this review summarizes the results of the researches realized in recent years in clinical trials and in various experimental models, on the effects of foods rich in polyphenols, polyphenolic extracts, and commercially polyphenols on insulin resistance and β-cells death. Dietary polyphenols are able to reduce insulin resistance alleviating the IRS-1/PI3-k/Akt signaling pathway, and to reduce the loss of pancreatic islet β-cell mass and function by several molecular mechanisms, such as protection of the surviving machinery of cells against the oxidative insult; increasing insulin secretion in pancreatic β-cells through activation of the FFAR1; cytoprotective effect on β-cells by activation of autophagy; protection of β-cells to act as activators for anti-apoptotic pathways and inhibitors for apoptotic pathway; stimulating of insulin release, presumably by transient ATP-sensitive K⁺ channel inhibition and whole-cell Ca²⁺ stimulation; involvement in insulin release that act on ionic currents and membrane potential as inhibitor of delayed-rectifier K⁺ current (I_K(DR)) and activator of current. dietary polyphenols could be used as potential anti-diabetic agents to prevent and alleviate diabetes and its complications, but further studies are needed.

Microalgae n-3 PUFAs Production and Use in Food and Feed Industries

N-3 polyunsaturated fatty acids (n-3 PUFAs), and especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential compounds for human health. They have been proven to act positively on a panel of diseases and have interesting anti-oxidative, anti-inflammatory or anti-cancer properties. For these reasons, they are receiving more and more attention in recent years, especially future food or feed development. EPA and DHA come mainly from marine sources like fish or seaweed. Unfortunately, due to global warming, these compounds are becoming scarce for humans because of overfishing and stock reduction. Although increasing in recent years, aquaculture appears insufficient to meet the increasing requirements of these healthy molecules for humans. One alternative resides in the cultivation of microalgae, the initial producers of EPA and DHA. They are also rich in biochemicals with interesting properties. After defining macro and microalgae, this review synthesizes the current knowledge on n-3 PUFAs regarding health benefits and the challenges surrounding their supply within the environmental context. Microalgae n-3 PUFA production is examined and its synthesis pathways are discussed. Finally, the use of EPA and DHA in food and feed is investigated. This work aims to define better the issues surrounding n-3 PUFA production and supply and the potential of microalgae as a sustainable source of compounds to enhance the food and feed of the future.

Omega-3 supplementation and diabetes: A systematic review and meta-analysis

This study aimed to review the literature on studies that evaluated the effects of omega-3 supplementation on parameters of diabetes in humans. An online search was conducted in the following databases: Pubmed, LILACS, Scielo, Scopus, and Web of Science. It included experimental studies that investigated the effects of omega-3 supplementation for diabetes treatment or prevention and its relationship with fasting blood glucose, insulin resistance, and glycated hemoglobin. Observational, non-human studies and non-randomized clinical trials were excluded. The Cochrane scale assessed the quality of the studies. A meta-analysis was carried out to evaluate the effect of omega-3 on fasting blood glucose, insulin resistance, and glycated hemoglobin. Thirty studies were included in the review. Almost 70% (n = 20) demonstrated at least one significant effect of the omega-3 supplementation related to diabetes. In the meta-analysis, there was a significant effect on the reduction of fasting blood glucose [SMD: -0.48; CI95%: -0.76, -0.19; p = 0.01; I2 = 88%] and insulin resistance [SMD: -0.61; CI95%: -0.98, -0.24; p = 0.01; I2 = 90%]. For glycated hemoglobin, there was no significant effect in the meta-analysis. This systematic review with meta-analysis demonstrated that supplementation with omega-3 has protective effects on diabetes parameters.

Implicating the effect of ketogenic diet as a preventive measure to obesity and diabetes mellitus

Obesity and diabetes are the two major metabolic complications linked with bad eating habits and the sedentary (lazy) lifestyle. In the worst-case situation, metabolic problems are a causative factor for numerous other conditions. There is also an increased demand to control the emergence of such diseases. Dietary and lifestyle improvements contribute to their leadership at an elevated level. The present review, therefore, recommends the use of the ketogenic diet (KD) in obesity and diabetes treatment. The KD involves a diet that replaces glucose sugar with ketone bodies and is effective in numerous diseases, such as metabolic disorders, epileptic seizures, autosomal dominant polycystic disease of the kidney, cancers, peripheral neuropathy, and skeletal muscle atrophy. A lot of high profile pathways are available for KD action, including sustaining the metabolic actions on glucose sugar, suppressing insulin-like growth factor-1 (IGF1) and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathways, altering homeostasis of the systemic ketone bodies, contributing to lowering diabetic hyperketonemia, and others. The KD regulates the level of glucose sugar and insulin and can thus claim to be an effective diabetes approach. Thus, a stopgap between obesity and diabetes treatment can also be evidenced by KD.

Fish oil reduces subclinical inflammation, insulin resistance, and atherogenic factors in overweight/obese type 2 diabetes mellitus patients: A pre-post pilot study

OBJECTIVE

Insulin resistance-associated obesity and type 2 diabetes mellitus (T2DM) are commonly accompanied with metabolic lipid abnormalities and are characterized by hypertriglyceridemia and low HDL-c levels (atherogenic index plasma, AIP). The primary molecular mechanism that is known to cause insulin resistance is chronic low-grade inflammation. Considering that omega-3 fatty acid reduces subclinical inflammation, we hypothesized that fish oil could affect insulin resistance and AIP. Therefore, the present study evaluated the effects of fish oil supplementation on the inflammatory, insulin resistance, and atherogenic factors in overweight/obese T2DM patients.

RESEARCH DESIGNS AND METHODS

In this study, we recruited 32 overweight and/or obese patients diagnosed with T2DM for over one year and who exhibited hypertriglyceridemia. These patients received fish oil supplementation (4.0 g/day) for eight weeks. Anthropometric and body composition measurements were obtained. In addition, blood samples were collected before and after omega-3 supplementation for the evaluation of lipid profile, glycemia, insulin, and inflammation.

RESULTS

As expected, patients showed reduction in the TNFα, IL-1β, and Il-6 levels after fish oil supplementation and showed improved insulin sensitivity (HOMA-IR) without observed alterations in anthropometric and body composition. These observations were followed by reduction in the levels of triglycerides and non-esterified fatty acids, increase in HDL cholesterol levels, and a significant reduction in triglycerides/HDL-c ratio, and total cholesterol/HDL-c ratio.

CONCLUSION

Fish oil supplementation is effective in reducing the levels of proinflammatory cytokines, improving insulin resistance, and reducing atherogenic factors in overweight/obese and T2DM patients independent of weight loss.

Is There Something Fishy About Fish Oil?

BACKGROUND

Fish is consumed as food worldwide and is considered as a rich source of essential nutrients required for a healthy life. Supplementation with fish oil has been adopted as a solution to prevent or cure many pathophysiological states and diseases by both the professionals and the civil population. The beneficial effects are, however, being questioned, as some controversial results were obtained in clinical and population studies.

METHODS

Critical evaluation of studies regarding known effects of fish oil, both in favour of its consumption and related controversies.

RESULTS

From the literature review, contradictory allegations about the positive action of the fish oil on human health emerged, so that a clear line about its beneficial effect cannot be withdrawn.

CONCLUSION

Scientific results on the application of fish oil should be taken with caution as there is still no standardised approach in testing its effects and there are significantly different baselines in respect to nutritional and other lifestyle habits of different populations.

Omega-3 Polyunsaturated Fatty Acids and Their Health Benefits

Omega-3 polyunsaturated fatty acids (PUFAs) include α-linolenic acid (ALA; 18:3 ω-3), stearidonic acid (SDA; 18:4 ω-3), eicosapentaenoic acid (EPA; 20:5 ω-3), docosapentaenoic acid (DPA; 22:5 ω-3), and docosahexaenoic acid (DHA; 22:6 ω-3). In the past few decades, many epidemiological studies have been conducted on the myriad health benefits of omega-3 PUFAs. In this review, we summarized the structural features, properties, dietary sources, metabolism, and bioavailability of omega-3 PUFAs and their effects on cardiovascular disease, diabetes, cancer, Alzheimer's disease, dementia, depression, visual and neurological development, and maternal and child health. Even though many health benefits of omega-3 PUFAs have been reported in the literature, there are also some controversies about their efficacy and certain benefits to human health.

Changes in Plasma Free Fatty Acids Associated with Type-2 Diabetes

Type 2 diabetes mellitus (T2DM) is associated with increased total plasma free fatty acid (FFA) concentrations and an elevated risk of cardiovascular disease. The exact mechanisms by which the plasma FFA profile of subjects with T2DM changes is unclear, but it is thought that dietary fats and changes to lipid metabolism are likely to contribute. Therefore, establishing the changes in concentrations of specific FFAs in an individual’s plasma is important. Each type of FFA has different effects on physiological processes, including the regulation of lipolysis and lipogenesis in adipose tissue, inflammation, endocrine signalling and the composition and properties of cellular membranes. Alterations in such processes due to altered plasma FFA concentrations/profiles can potentially result in the development of insulin resistance and coagulatory defects. Finally, fibrates and statins, lipid-regulating drugs prescribed to subjects with T2DM, are also thought to exert part of their beneficial effects by impacting on plasma FFA concentrations. Thus, it is also interesting to consider their effects on the concentration of FFAs in plasma. Collectively, we review how FFAs are altered in T2DM and explore the likely downstream physiological and pathological implications of such changes.

The risk of metabolic syndrome as a result of lifestyle among Ellisras rural young adults

The study aimed to investigate the association between metabolic syndrome (MetS) and lifestyle risk factors among Ellisras adults. A cross-sectional study was conducted on 624 adults (306 males and 318 females). MetS was defined according to the criteria of the International Diabetes Federation. The prevalence of MetS was 23.1% (8.6% males and 36.8 % females). Females appeared to have higher mean values for waist circumference (WC), fasting blood glucose (FBG), total cholesterol (TCHOL) and low-density lipoprotein cholesterol (LDL-C), while males had high mean values for high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), systolic blood pressure (SBP) and diastolic blood pressure (DBP). No significant age and gender differences were observed for dietary intake. Significantly more females (51.9%) presented with increased WC than males (4.6%). Participants who had a high dietary energy intake were significantly less likely to present with larger WC (OR: 0.250 95% CI [0.161; 0.389]), low HDL-C (OR: 0.306 95% CI [0.220; 0.425]) and high LDL-C (OR: 0.583 95% CI [0.418; 0.812]) but more likely to present with elevated FBG (OR: 1.01 95% CI [0.735; 1.386]), high TCHOL (OR: 1.039 95% CI [0.575; 1.337]), high TG (OR: 1.186 95% CI [0.695; 2.023]) and hypertension (OR: 5.205 95% CI [3.156; 8.585]). After adjusting for age, gender, smoking, and alcohol status, high energy intake was more than two times likely to predict MetS in adults with a large WC (OR: 2.766 95% CI [0.863; 3.477] and elevated FBG (OR: 2.227 95% CI [1.051; 3.328]). Therefore, identifying groups that are at an increased risk and those that are in their early stages of MetS will help improve and prevent the increase of the MetS in the future.

Effect of nutritionally induced hyperlipidaemia on in vitro bovine embryo quality depends on the type of major fatty acid in the diet

The present study examined whether the effects of dietary-induced hyperlipidaemia on preimplantation embryo development depend on the predominant fatty acid (FA) type in the diet. In a combined in vivo-in vitro bovine model, two groups of cows (n=3 in each group) were fed with three diets consecutively (4 weeks feeding for each): (1) a maintenance control diet (CONT); (2) a high-starch diet rich in saturated fat (SAT); and (3) a high-starch diet rich in omega-3 unsaturated fat (UNSAT). Two feeding sequences were used to test for carry-over effects: Group A was fed CONT, SAT1 and then UNSAT2, whereas Group B was fed CONT, UNSAT1 and then SAT2. Serum was collected after each dietary period, analysed and tested in bovine in vitro embryo culture. Introducing SAT and UNSAT diets induced hyperlipidaemia (specifically hypercholesterolaemia and elevated free FAs) and reduced insulin sensitivity. Carry-over effects in serum metabolites and FA profile were dependent on the diet and feeding sequence. SAT1 and SAT2 serum decreased blastocyst rates and altered blastocyst mRNA expression related to apoptosis and oxidative stress. UNSAT1 and UNSAT2 serum resulted in normal embryo development and quality. Other in vitro effects depended on the sequence of feeding. In conclusion, substitution of saturated fat with omega-3 fat in a high-caloric diet induced hyperlipidaemia with an FA profile yielding similar rates and quality of blastocysts compared with normolipidaemic controls.

Effects of dietary palm olein on the cardiovascular risk factors in healthy young adults

BACKGROUND

Dietary saturated fatty acids are always being hotly debated. Palm olein rich in saturated fatty acids (45.98%) is often considered as being atherogenic nutritionally. There is a lack of information on effects of dietary oil by partially replacing with palm olein on human health.

METHODS

A randomized controlled trial with 88 participants has been conducted to elucidate the effect of palm olein on cardiovascular risk factors.

RESULTS

By comparing the soybean oil group (saturated fatty acids amounted to 23.31%) with the cocoa butter group (saturated fatty acids amounted to 93.76%), no significant difference was found (p > 0.05) in physiological parameters, serum oxidative stress levels, inflammatory factor, glucose metabolism, and lipid profiles of subjects, which are all cardiovascular risk factors. Although results showed that intervention time can influence the cardiovascular risk factors significantly (p < 0.05), there is no relationship between intervention time and dietary oil type.

CONCLUSION

Therefore, partial replacement of dietary oil by palm olein may not affect cardiovascular risk factors in healthy young adults. There are differences between our research and previous researches, which may be due to the different amount of palm olien in diet. Our research will provide a solid foundation for the application of palm olein in human diets and in the food industry.

The role of polyunsaturated fatty acids (n-3 PUFAs) on the pancreatic β-cells and insulin action

Polyunsaturated Fatty acids have multiple effects in peripheral tissues and pancreatic beta cell function. The n-3 Polyunsaturated Fatty acids prevent and reverse high-fat-diet induced adipose tissue inflammation and insulin resistance. Insulin secretion is stimulated by glucose, amino acids, and glucagon- like peptide-1 in tissue containing high levels of n-3 Polyunsaturated Fatty acids than lower level of n-3 Polyunsaturated Fatty acids. Also, n-3 Polyunsaturated Fatty acids led to decreased production of prostaglandin, which in turn contributed to the elevation of insulin secretion. N-3 polyunsaturated fatty acids prevent cytokine-induced cell death in pancreatic islets. Supplementation of n-3 Polyunsaturated Fatty acids for human subjects prevent beta cell destruction and insulin resistance. It also enhances insulin secretion, reduction in lipid profiles and glucose concentration particularly in type II diabetes patients. Therefore there should be a focus on the treatment mechanism of insulin related obesity and diabetes by n-3 polyunsaturated fatty acids.

Fish oil supplementation and insulin sensitivity: a systematic review and meta-analysis

Background

Fish oil supplementation has been shown to be associated with a lower risk of metabolic syndrome and benefit a wide range of chronic diseases, such as cardiovascular disease, type 2 diabetes and several types of cancers. However, the evidence of fish oil supplementation on glucose metabolism and insulin sensitivity is still controversial. This meta-analysis summarized the exist evidence of the relationship between fish oil supplementation and insulin sensitivity and aimed to evaluate whether fish oil supplementation could improve insulin sensitivity.

Methods

We searched the Cochrane Library, PubMed, Embase database for the relevant studies update to Dec 2016. Two researchers screened the literature independently by the selection and exclusion criteria. Studies were pooled using random effect models to estimate a pooled SMD and corresponding 95% CI. This meta-analysis was performed by Stata 13.1 software.

Results

A total of 17 studies with 672 participants were included in this meta-analysis study after screening from 498 published articles found after the initial search. In a pooled analysis, fish oil supplementation had no effects on insulin sensitivity compared with the placebo (SMD 0.17, 95%CI -0.15 to 0.48, p = 0.292). In subgroup analysis, fish oil supplementation could benefit insulin sensitivity among people who were experiencing at least one symptom of metabolic disorders (SMD 0.53, 95% CI 0.17 to 0.88, p < 0.001). Similarly, there were no significant differences between subgroups of methods of insulin sensitivity, doses of omega-3 polyunsaturated fatty acids (n-3 PUFA) of fish oil supplementation or duration of the intervention. The sensitivity analysis indicated that the results were robust.

Conclusions

Short-term fish oil supplementation is associated with increasing the insulin sensitivity among those people with metabolic disorders.

Omega 3 Fatty Acids Reduce Bone Resorption While Promoting Bone Generation in Rat Apical Periodontitis

INTRODUCTION

This study evaluated the effects of the dietary supplement omega 3 polyunsaturated fatty acids (ω-3 PUFAs) on pulp exposure-induced apical periodontitis (AP) in rats.

METHODS

Twenty-eight male rats were divided into groups: control untreated rats (C), control rats treated with ω-3 PUFAs alone (C-O), rats with pulp exposure-induced AP, and rats with pulp exposure-induced AP treated with ω-3 PUFAs (AP-O). The ω-3 PUFAs were administered orally, once a day, for 15 days before pulp exposure and, subsequently, 30 days after pulp exposure. Rats were killed 30 days after pulp exposure, and jaws were subjected to histologic and immunohistochemical analyses. Immunohistochemical analyses were performed to detect tartrate-resistant acid phosphatase-positive osteoclasts and osteocalcin-positive osteoblasts on the bone surface of periapical area. Results were statistically evaluated by using analysis of variance and Tukey honestly significant difference, and P < .05 was considered statistically significant.

RESULTS

The bone resorption lesion was significantly larger in the AP group compared with AP-O, C, and C-O groups (P < .05). The level of inflammatory cell infiltration was significantly elevated, and the number of tartrate-resistant acid phosphatase-positive osteoclasts was significantly higher in the periapical lesions of the AP group compared with AP-O, C, and C-O groups (P < .05). The number of osteocalcin-positive osteoblasts was significantly increased in the AP-O group compared with the AP group (P > .05).

CONCLUSIONS

Supplementation with ω-3 PUFAs not only suppresses bone resorption but also promotes new bone formation in the periapical area of rats with AP in conjunction with downregulation of inflammatory cell infiltration into the lesion.

Role of phytochemicals in the management of metabolic syndrome

BACKGROUND

The World Health Organization (WHO) for some years has been focusing on what is now commonly referred to as an "epidemic of obesity and diabetes" ("diabesity"): behind this outbreak, there are several risk factors grouped in what is called "metabolic syndrome" (MetS). The basis of this "epidemic" is either a diet too often characterized by excessive consumption of saturated and trans-esterified fatty acids, simple sugars and salt, either a sedentary lifestyle.

PURPOSE

The aim of this review is to focus on the phytochemicals that have a more positive effect on the treatment and/or prevention of MetS.

CHAPTERS

Treatment strategies for MetS include pharmacologic and non-pharmacologic options, with varying degrees of success rate. The first is indicated for patients with high cardiovascular risk, while the second one is the most cost-effective preventive approach for subjects with borderline parameters and for patients intolerant to pharmacological therapy. MetS non-pharmacological treatments could involve the use of nutraceuticals, most of which has plant origins (phytochemicals), associated with lifestyle improvement. The chapter will discuss the available evidence on soluble fibres from psyllium and other sources, cinnamaldehyde, cinnamic acid and other cinnamon phytochemicals, berberine, corosolic acid from banaba, charantin from bitter gourd, catechins and flavonols from green tea and cocoa. Vegetable omega-3 polyunsaturated fatty acids, alliin from garlic, soy peptides, and curcumin from curcuma longa.

CONCLUSION

Some nutraceuticals, when adequately dosed, should improve a number of the MetS components.

Insulin-Sensitizing Effects of Omega-3 Fatty Acids: Lost in Translation?

Omega-3 polyunsaturated fatty acids (n-3 PUFA) of marine origin, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), have been long studied for their therapeutic potential in the context of type 2 diabetes, insulin resistance, and glucose homeostasis. Glaring discordance between observations in animal and human studies precludes, to date, any practical application of n-3 PUFA as nutritional therapeutics against insulin resistance in humans. Our objective in this review is to summarize current knowledge and provide an up-to-date commentary on the therapeutic value of EPA and DHA supplementation for improving insulin sensitivity in humans. We also sought to discuss potential mechanisms of n-3 PUFA action in target tissues, in specific skeletal muscle, based on our recent work, as well as in liver and adipose tissue. We conducted a literature search to include all preclinical and clinical studies performed within the last two years and to comment on representative studies published earlier. Recent studies support a growing consensus that there are beneficial effects of n-3 PUFA on insulin sensitivity in rodents. Observational studies in humans are encouraging, however, the vast majority of human intervention studies fail to demonstrate the benefit of n-3 PUFA in type 2 diabetes or insulin-resistant non-diabetic people. Nevertheless, there are still several unanswered questions regarding the potential impact of n-3 PUFA on metabolic function in humans.

Dietary fat intake and its association with risk of selected components of the metabolic syndrome among rural South Indians

CONTEXT

There is limited literature on the dietary fat intake of rural Indian populations, particularly in relation to the risk of metabolic syndrome (MS).

AIM

This study aims to assess the dietary fat intake and analyze its association with the risk of selected components of the MS among rural population in the state of Tamil Nadu.

SETTINGS AND DESIGN

Adults (n = 27012) ≥20 years of age were recruited from the rural component of the Chennai Urban Rural Epidemiological Study, a cross-sectional study conducted in 42 villages in Kanchipuram District of Tamil Nadu.

SUBJECTS AND METHODS

Using a validated food frequency questionnaire, data were obtained on the fat intake among 6907 adults. Anthropometric and clinical measures were collected using standard methods. The components of the MS assessed were abdominal obesity, hypertension, and impaired fasting glucose. All analyses were performed using SPSS software (version 20).

RESULTS

Prevalence of abdominal obesity, hypertension, and impaired fasting glucose were significantly higher in the highest quintile of fat intake (33%, P < 0.001; 39%, P = 0.04, and 23.3%, P = 0.003, respectively). Highest intake of fat was also significantly associated with risk of abdominal obesity (P < 0.001), hypertension (P = 0.04), and impaired fasting glucose (P = 0.01). Sunflower oil as the main cooking oil was significantly associated with a higher risk of these components of the MS (P for trend <0.001) compared to traditional oils and palmolein.

CONCLUSIONS

Higher dietary fat was significantly associated with risk of components of the MS and use of sunflower oil as main cooking oil increased metabolic risk in rural South Indians.