Tropical Oils Research Articles

Enzymatic Inter‐Esterification of Binary Blends Containing Irvingia gabonensis Seed Fat to Produce Cocoa Butter Substitute

In order to investigate Irvingia gabonensis seed fat (IGF) as a potential cocoa butter alternative (CBA), its melting behavior is first compared to that of cocoa butter (CB). It is then modified by blending 90% of this fat with 10% of a liquid oil either rapeseed oil (RO) or groundnut oil (GO) or palm super olein (PSO) or Dacryodes edulis pulp oil (DPO). Those blends are then enzymatically interesterified in order to improve their melting profiles. The binary blend that shows a similar profile with CB and palm kernel stearin (PKS) is chosen as the best potential new speciality fat. Compatibility between the new speciality fat and CB is evaluated by constructing phase diagrams from NMR and XRD data. The interesterified blends with 90% of IGF and 10% of DPO is chosen as the new speciality fat because its profiles is close to that of CB and shows similar characterics to PKS. The results indicate that the specialty fat produced from IGF and DPO could be used as CBS in confectionery industries (alone or mixed in low proportion with CB).Practical Applications: Fractionnated and/or hydrogenated lauric fats are frequently used by confectionery industries to substitute CB. Results from this study demonstrate that an interesterified blend made of 90% IGF and 10% of DPO can be used also as CBS. The use of these two tropical oils (Irvingia gabonensis seeds fat and Dacryodes edulis pulp oil) as new sources of CBS constitutes a promizing way for their valorization at an industrial scale.Irvingia gabonensis seed fat (IGF) is a naturel lauric fat source with a high quantity of lauric acid (≈37%). Its melting profile, which is similar to cocoa butter (CB), is too high for a direct use in its native state in confectionery application. When IGF is blend to Dacryodes edulis pulp oil and after enzymatically interesterified, its profile is close to that of CB. This result indicated that the interesterified blend can be used as cocoa butter subtitute in confectionery industries (alone or mixed in low proportion with CB).

Energy Valorization by Continuous Pyrolysis of Straight Vegetable Oils (SVOs)

Researches have been undertaken to find a form of valorization of the surplus production of vegetable oils in C&#244te d’Ivoire for their use as a substitute diesel. The first tests of the use of crude oils-diesel blends by the company Palmindustrie faced enormous difficulties. We have therefore undertaken a campaign of pyrolysis of Tropical Straight Vegetable Oils: palm, copra, peanut, cotton, cabbage palm and shea, between 400°C and 600°C under atmospheric pressure. A silica support was used in co-catalysis either with water or with methylcyclohexane, which is a model compound of cetanes contained in gas oil. This compound has the advantage, unlike the gas oil itself, of not masking the peaks of the pyrolysis recombinates of oils in the chromatograms. The condensed organic phase consists mainly of hydrocarbons including paraffins, olefins, alkylbenzenes and styrenes. The yields of liquid hydrocarbons vary between 72% and 86%. A comparative study of coke precursors and gas production was carried out. A discussion on the parameters to be considered for a large-scale implementation was undertaken.

Transesterification of Tropical Edible Oils to Biodiesel Using Catalyst From Scylla serrata

Abstract: Scylla serata shell was decomposed at various temperatures ranging from 700-1100 o C to obtain calcium oxide. Calcium oxide from decomposed Scylla serrata shell was characterized through X-Ray analysis, FTIR spectroscopy, and morphology analysis. Furthermore, decomposed Scylla serrata shell was used as catalyst for transesterification of tropical edible oils to form biodiesel. Biodiesel was characterized through density, viscosity, fatty acid value, and iodine number. The results showed that decomposed Scylla serrata shell at 900 o C could produce calcium oxide similar with standard, which was indicated from X-ray powder diffraction pattern of decomposed shell with JCPDS data. FTIR spectrum showed that main vibration of calcium oxide was observed at 393 cm -1 . Morphology analysis using SEM indicated that uniform calcium oxide was obtained after decomposition. The use of decomposed shell as base catalyst for transesterification of tropical edible oils resulted biodiesel with density, viscosity, fatty acid value, and iodine number appropriated with SNI standard. Keywords: transesterification, edible oils, biodiesel, Scylla serrata Abstrak (Indonesian) : Scyalla serrata telah didekomposisi pada berbagai suhu dari 700-1100 o C untuk diperoleh kalsium oksida. Kalsium oksida hasil dekomposisi dari cangkang Scylla serrata dikarakterisasi melalui pengukuran sinar X, analisis FTIR, dan analisis morfologi. Lebih lanjut, dekomposisi cangkang Scylla serrata digunakan sebagai katalis transesterifikasi minyak yang dimakan dari daerah tropis menjadi biodisel. Biodiesel dikarakterisasi melalui penentuan densitas, viskositas, nilai asam lemak, dan bilangan iod. Hasil penelitian menunjukkan bahwa dekomposisi cangkang Scylla serrata pada 900 o C dapat menghasilkan kalsium oksida mirip kalsium oksida standar yang diindikasikan dari pola difraksi XRD yang mirip data JCPDS. Spektrum FTIR menunjukkan vibrasi utama kalsium oksida teramati pada bilangan gelombang 393 cm -1 . Analisis morfologi menggunakan SEM menunjukkan bahwa bentuk yang lebih seragam diperoleh setelah proses dekomposisi. Penggunaan cangkang hasil dekomposisi sebagai katalis basa untuk transesterifikasi minyak yang dimakan dari daerah tropis menghasilkan biodisel dengan densitas, viskositas, nilai asam lemak, dan bilangan iod yang sesuai dengan standar SNI. Kata kunci: transesterifikasi, minyak yang dimakan dari daerah tropis, biodiesel, Scylla serrata

Dietary and Policy Priorities for Cardiovascular Disease, Diabetes, and Obesity: A Comprehensive Review.

Suboptimal nutrition is a leading cause of poor health. Nutrition and policy science have advanced rapidly, creating confusion yet also providing powerful opportunities to reduce the adverse health and economic impacts of poor diets. This review considers the history, new evidence, controversies, and corresponding lessons for modern dietary and policy priorities for cardiovascular diseases, obesity, and diabetes mellitus. Major identified themes include the importance of evaluating the full diversity of diet-related risk pathways, not only blood lipids or obesity; focusing on foods and overall diet patterns, rather than single isolated nutrients; recognizing the complex influences of different foods on long-term weight regulation, rather than simply counting calories; and characterizing and implementing evidence-based strategies, including policy approaches, for lifestyle change. Evidence-informed dietary priorities include increased fruits, nonstarchy vegetables, nuts, legumes, fish, vegetable oils, yogurt, and minimally processed whole grains; and fewer red meats, processed (eg, sodium-preserved) meats, and foods rich in refined grains, starch, added sugars, salt, and trans fat. More investigation is needed on the cardiometabolic effects of phenolics, dairy fat, probiotics, fermentation, coffee, tea, cocoa, eggs, specific vegetable and tropical oils, vitamin D, individual fatty acids, and diet-microbiome interactions. Little evidence to date supports the cardiometabolic relevance of other popular priorities: eg, local, organic, grass-fed, farmed/wild, or non-genetically modified. Evidence-based personalized nutrition appears to depend more on nongenetic characteristics (eg, physical activity, abdominal adiposity, gender, socioeconomic status, culture) than genetic factors. Food choices must be strongly supported by clinical behavior change efforts, health systems reforms, novel technologies, and robust policy strategies targeting economic incentives, schools and workplaces, neighborhood environments, and the food system. Scientific advances provide crucial new insights on optimal targets and best practices to reduce the burdens of diet-related cardiometabolic diseases.

Saturated fat and heart disease: The latest evidence

In recent years, many nutrition news headlines exclaimed that saturated fat was not linked to heart disease, leaving the public confused about whether to limit intake, as has been the dietary recommendation for several decades. However, a more nuanced look at the evidence indicates that high saturated fat diets are in fact not benign with respect to heart disease risk. Dietary recommendations should emphasize replacing saturated fats typical in red and processed meats, and certain tropical oils and dairy forms, with healthier polyunsaturated and monounsaturated fat‐rich foods, such as nuts, olive oil, and fatty fish, as well as healthy sources of carbohydrates, such as fiber‐rich whole‐grain foods, rather than refined‐grain and sugar‐laden foods.

Plasma capric acid concentrations in healthy subjects determined by high-performance liquid chromatography.

Capric acid (FA10:0, decanoic acid) is a medium-chain fatty acid abundant in tropical oils such as coconut oil, whereas small amounts are present in milk of goat, cow, and human. Orally ingested FA10:0 is transported to the liver and quickly burnt within it. Only few reports are available for FA10:0 concentrations in human plasma. Fasting (n = 5, male/female = 3/2, age 31 ± 9.3 years old) and non-fasting (n = 106, male/female = 44/62, age 21.9 ± 3.2 years old) blood samples were collected from apparently healthy Japanese volunteers. The total FA10:0 in the plasma were measured by high-performance liquid chromatography after derivatization with 2-nitrophenylhydrazine followed by UV detection. Inter and intra-assay coefficient of variation of FA10:0 assay at three different concentrations ranged in 1.7-3.9 and 1.3-5.4%, respectively, with an analytical recovery of 95.2-104.0%. FA10:0 concentration was below detection limit (0.1 µmol/L) in each fasting human plasma. FA10:0 was not detected in 50 (47.2%) of 106 non-fasting blood samples, while 29 (27.4%) plasma samples contained FA10:0 less than or equal to 0.5 µmol/L (0.4 ± 0.1), and 27 (25.5%) contained it at more than 0.5 µmol/L (0.9 ± 0.3). A half of the non-fasting plasma samples contained detectable FA10:0. This simple, precise, and accurate high-performance liquid chromatography method might be useful for monitoring plasma FA10:0 during medium-chain triglycerides therapy.

Baking Those Delicious “Good-for-You” Products

A “good-for-you” baked product can be enhanced in two ways—either by adding something to increase its health benefits or by taking out some of the components that are bad for you. Popular targets for removal include fats, sugars, saturated fats, tropical oils and trans-fat, cholesterol, sodium, carbohydrates, and gluten. Possible beneficial additions include whole grains, fiber, proteins, flaxseed, omega 3 fatty acids, β-glucan, antioxidants, vitamins, and fruits. Possible methods of removing and adding ingredients to improve the benefits of baked products are discussed.

Effects of nutrition labeling on edible oil processing and consumption patterns in the US

AbstractThe period from 2003 to present has had a profound effect on the edible oil industry. Health/nutrition issues including trans, saturated and omega‐3 acids in the diet have impacted the soybean market, edible oil consumption patterns and consumer perception of lipid based foods. In order to satisfy the concerns, much technology has been developed to remove trans/saturated fats from the food supply. Processors have turned from hydrogenation to chemical or enzymatic modification, modified oil hardening to formulate low/zero trans products and increased use of tropical oils. Trait modified oilseeds have been developed and commercialized and are no longer niche crops supplying about 18% of domestic food oil needs.

Huiles et corps gras des Pays du Sud et lipochimie

During the last decades the oleochemistry has gradually flooded our everyday life through a mass of products and applications. This is mainly due to the wide structural diversity and reactivity of fatty acids and the growing demand for bio-sourced goods. Today, almost one quarter of the global vegetable oil production is dedicated to nonfood applications, the contribution of animal fats being much more modest. Excepted biodiesels, the chemical applications of tropical edible oils depend on their fatty acids composition: lauric oils (coconut and palm kernel) and palm stearin will be mostly converted into surface actives ingredients while unsaturated oils rather will be subjected to double bond functionalization or cracking. Alongside of major vegetable oils only a few non-edible tropical oils are exclusively intended to oleochemistry such as Castor and Jatropha. Some other non-food oilseed crops (Cuphea, Lesquerella, Vernonia, black mustard. . .) are promising but further researches are still needed for their development in Southern Countries. In the future, the production increase of major vegetable oils and the development of new ones will face many challenges relating to environmental issues, competition between food and non-food uses and between non-food applications themselves.

Structuring oils without highly saturated fats – how far are we?

Eckhard Flöter The interest to structure oil-based products with materials different from highly saturated fats has increased significantly during the time when ‘fat technologists’ were busy to find solutions to reduce and widely eliminate trans fatty acids from our food products. Next to the trans fatty acid elimination the reduction of saturated fatty acids has become a generally acknowledged target. This is expressed in the FAO/WHO goal to limit the energy intake from saturated fatty acids to 10%. The motivation to develop alternative structuring technologies for soft-solid lipid phases could increase beyond current ‘low SaFA’-claims through ongoing discussions on the taxation of saturated fats in products as currently present in Denmark and additionally the risk that the application of natural saturated fatty acids, with palm oil as primary source, becomes more complicated. The latter could be either due to availability issues driven by competing usages or developments of the public opinion with regard to the consumption of tropical oils. As an alternative to replace saturated fats organogelators are now of considerable interest. In simple terms the desired organogelators are to vegetable oils the analogue of what gelatine and other biopolymers are with respect to the structuring of water. These structurants, preferentially applied at low concentration levels, deliver semi-solid lipid phases that have practically the same lipid nutritional profile as liquid oils. Oil structuring or organogelation is not new and the field of organogels outside food is highly active. Non-food applications cover optical materials, drug delivery systems, oil spill recovery techniques, and home and personal care products. Even though the limitation to edible applications reduces the number of candidate structuring materials the size of the haystack for searching some magic needles is still sizable. The scientific efforts of the past decade have not yet delivered a true breakthrough and hence the door for broad food applications of organogels is still closed. The structuring systems that have been studied can arbitrarily be categorized in three classes. First, there are the obvious one component systems familiar to the products considered such as waxes, fatty acids, fatty alcohols and mono- and diacylglycerols. These seem to deliver only limited, if at all, benefits over triacylglycerols. However, in this category of single structurants, materials such as ceramides and 12-hydroxystearic acid offer a clear SaFA benefit compared to structuring vegetable oils by fat crystals. Second, there is a class of composed structuring systems. These usually binary systems such as β-sitosterol and oryzanol, or fatty acids and fatty alcohol, the combination lecithin and sorbitolesters are unfortunately very prone to losing their structuring potential in product applications. This is for example due to either the presence of an oil-water interface or the formation of hydrates that tend to deplete the self-assembled structure in at least one of its components. Third, there is oil structuring through components that are alien to the products considered and mostly deliberately synthesized. Here, ethylcellulose and protein fibrils have to be mentioned. The field of edible oil structuring and the current status of different approaches has been reviewed and discussed repeatedly 1-3. Undoubtedly substantial progress has been made with respect to the number of different structuring systems and the comprehension of their mechanism of action. However, the step from gelling oil on the laboratory bench to deliver a robust structured lipid phase in a food product appears to be quite big. At first some structuring systems are just too costly or the availability of the necessary material is limited. Secondly, food products and their manufacturing processes appear to be quite hostile for oil structuring systems because oil–water interfaces, water activity levels or shear during manufacturing can be critical for the organogels. Additionally, the perceivable properties of gelled oils are different from conventional semi-solid lipid phases. Typically there will be no cooling sensation and also other product disintegration characteristics will change. This is understandably a major obstacle in any product development effort. However, the time might be ripe to selectively move oil structuring from the laboratory bench towards product development. Recently a good example of a successful product application was reported by Zetzl et al. 4. Here the domains of animal fat in Frankfurter sausages were substituted by pieces of ethylcellulose structured vegetable oil. Since it is unlikely that a single oil structuring system will be a general substitute for fat crystals one can expect different application specific structuring solutions varying from hybrid systems, combinations of saturated TAG and organogelators, to full replacement of the structuring fat. Finally, the future market success of organogel-based products will not only depend on the technical ability to formulate acceptable products, which is certainly easier for completely new ones without any reference perception, but also on the ‘consumer digestible’ communication concerning the structuring materials. Eckhard Flöter Editor

Effects of Transesterification Variables on the Characteristics of the Methyl Esters Obtained from Four Virgin Tropical Seed Oils in Nigeria

Effects of Transesterification Variables on the Characteristics of the Methyl Esters Obtained from Four Virgin Tropical Seed Oils in Nigeria

Palm Oil and Health: A Case of Manipulated Perception and Misuse of Science

In the 1980s, a combination of forces came together to convince the public that food products containing tropical oils contributed to their risk of coronary heart disease. Tropical oils were competing with the U.S. soy bean oil market as an alternative vegetable oil, yet they were higher in saturated fat, which had become the target of the health promotion community for its theoretical association with coronary heart disease risk. Successful national campaigns were undertaken to force food manufacturers to remove tropical oils, including palm oil, from their products and to replace them with hydrogenated vegetable oils, resulting in increased intakes of trans-fatty acids, which later became the target of the same advocacy groups. Today palm oil is being touted as a suitable replacement for hydrogenated vegetable oils.

BLENDING OF JATROPHA OIL WITH OTHER VEGETABLE OILS TO IMPROVE COLD FLOW PROPERTIES AND OXIDATIVE STABILITY OF ITS BIODIESEL

ABSTRACT Jatropha oil has rich in unsaturated fatty acids, but other tropical oils, such as palm oil and coconut oil, have high saturated fatty acid. Blending of jatropha biodiesel with soybean, rapeseed, palm and coconut biodiesels resulted in different propertie, between properties of each pure compounds or even better than pure biodiesel. Jatropha biodiesel in concentration of 50-70% jatropha-coconut blend had better cloud point and pour point (9 oC and -6 oC, respectively), compare to jatropha biodiesel (12 oC, 0 oC) and coconut biodiesel (15 oC, 9 oC). Blending of jatropha and coconut were further investigated using two methods, namely methods 1 was in the form of biodiesel and method 2 was in the form of oil before biodiesel processing. Blending method 2 resulted in higher cloud point and lower pour point compared to method 1 and the values were relatively constant. Blending of 55% of jatropha biodiesel with lauric biodiesel (75% lauric methylester) showed a minimum cloud point and pour point (-3 oC; -18 oC). This minimum point called eutectic point expressed an ideal equilibrium of liquid-solid among saturated medium chain alkyl esters and unsaturated long chain alkyl esters. Methylester composition of this biodiesel was 34.03% lauric, 0.31% miristic, 8.91% palmitic, 3.82% stearic and 46.17% oleic acids. This proved the important role of lauric acid, a medium chain saturated fatty acid, which was dominant in coconut biodiesel (48.11%). Keyword: jatropha biodiesel, blending, cloud point, pour point

Impact of Dietary Fatty Acids on Cardiac Arrhythmogenesis

A recent headline on theHeart.org was “Western Diet Increases MI Risk Worldwide.” In the past 30 years, it has become apparent that dietary fatty acids have a profound impact on the composition of plasma and cardiovascular tissue lipid pools, and as a result, on the risks of cardiovascular disease. Although significant progress has been made to reduce the incidence of death caused by coronary heart disease, it still afflicts ≈450 000 patients per year in the United States, with many of these dying from cardiac arrhythmias.1 Atrial fibrillation (AF), the most common arrhythmia, afflicts more than 2.2 million Americans. It has been estimated that more than 12 million Americans will have AF by 2050 because of the aging of the population as well as the increasing incidence of diabetes and obesity, both risk factors for AF.1 Reasons underlying the increased prevalence of these acquired diseases are complex, involving societal changes in diet, lifestyle, and physical activity. Efforts to address these risk factors seem likely to reduce the burden of cardiac arrhythmia and cardiovascular disease. Although all are important, this review focuses on the relationship between dietary fatty acids and mechanisms of cardiac arrhythmogenesis. ### What Fatty Acids Are Present in the Diet? As shown in Figure 1, fatty acids consist of a straight chain of carbon atoms with a carboxylic end (COOH) and a methyl (CH3) or omega end and are classified based on the saturation of the carbon chain. Common saturated fatty acids, those with no double bonds, include palmitic acid (16:0) and stearic acid (18:0). Foods high in saturated fatty acids include dairy products, red meats, and tropical oils.2 Unsaturated fatty acids are further classified based on the number and location of double bonds. Monounsaturated fatty acids, such as oleic acid (18:1n9), have a single double bond, whereas polyunsaturated fatty acids (PUFA) …

Le rôle croissant des huiles tropicales sur les marchés internationaux : principaux acteurs et produits

In the last thirty years, the international market for vegetable oils has developed substantially especially in terms of production and international trade. Three tropical oils: coconut, palm kernel and mainly palm oil and three countries: Indonesia, Malaysia and to a lesser extent the Philippines and play a major role in the supply of lipids to the rest of the world. Palm oil prices are generally lower than other vegetable oils such as soybean, rapeseed and sunflower, but since the beginning of 2006, they have risen steeply, as prices for most of agricultural products traded in the world, before showing a huge drop by the middle of the 2008 crop year. As palm has the most important oil yield among oilseed crops, future development of tropical oils is a major issue for the world market over the next years. There will be a growing food demand coming from areas in deficit of oilseed products (China, South Asia, Africa, etc.); these countries experience rapid demographic growth and increase in per capita consumption of oils and fats due to income growth during the last decade. Tropical oils could also play a major role in non-food sectors like lipid chemistry and biodiesel, either to be directly used in this production or to substitute other vegetable oils previously used for human food more and more used for bioenergy.

Feasibility of recommending certain replacement or alternative fats

Expert groups and public health authorities recommend that trans-fatty acid (TFA) intakes from industrially produced partially hydrogenated vegetable oils (PHVOs) should be less than 1% of total energy intake. The starting point for any regulatory or nonregulatory response to this recommendation is to assess the extent of the problem by determining where in the food supply TFAs are found and the amounts consumed in the population. Unfortunately, this is a particularly difficult task using traditional methods of dietary assessment inasmuch as food composition databases with TFA data are either nonexistent or incomplete in most countries. Current evidence on estimates of intake suggests there is high variability in TFA intakes and their food sources between countries. The ubiquitous presence of PHVOs in the global food supply in bakery products, deep-fried foods, snack foods, confectionery products and table spreads attests to their commercial value and convenience. However, their common use is more the result of historical convenience from an industry infrastructure developed over 50 years based on efficient, cost-effective hydrogenation of vegetable oils rather than any inherent sensory or physical superiority of the hydrogenated fats over purpose-made zero-trans fats and oils. Current global supply of appropriate zero-trans replacement fats high in cis-unsaturated fatty acids is insufficient to meet the demand if all PHVOs in the food supply were replaced. Regulatory action needs to be coordinated with supply to maximize the opportunity for health gains by replacing partially hydrogenated fats with purpose-ready zero-trans vegetable oils low in saturates and high in cis-unsaturates rather than animal fats and tropical oils high in saturated fatty acids.

Chemical Composition, Antioxidant Properties, and Thermal Stability of a Phytochemical Enriched Oil from Açai (Euterpe oleraceaMart.)

Phenolic compounds present in crude oil extracts from acai fruit ( Euterpe oleracea) were identified for the first time. The stability of acai oil that contained three concentrations of phenolics was evaluated under short- and long-term storage for lipid oxidation and phenolic retention impacting antioxidant capacity. Similar to acai fruit itself, acai oil isolates contained phenolic acids such as vanillic acid (1,616 +/- 94 mg/kg), syringic acid (1,073 +/- 62 mg/kg), p-hydroxybenzoic acid (892 +/- 52 mg/kg), protocatechuic acid (630 +/- 36 mg/kg), and ferulic acid (101 +/- 5.9 mg/kg) at highly enriched concentrations in relation to acai pulp as well as (+)-catechin (66.7 +/- 4.8 mg/kg) and numerous procyanidin oligomers (3,102 +/- 130 mg/kg). Phenolic acids experienced up to 16% loss after 10 weeks of storage at 20 or 30 degrees C and up to 33% loss at 40 degrees C. Procyanidin oligomers degraded more extensively (23% at 20 degrees C, 39% at 30 degrees C, and 74% at 40 degrees C), in both high- and low-phenolic acai oils. The hydrophilic antioxidant capacity of acai oil isolates with the highest phenolic concentration was 21.5 +/- 1.7 micromol Trolox equivalents/g, and the total soluble phenolic content was 1252 +/- 11 mg gallic acid equivalents/kg, and each decreased by up to 30 and 40%, respectively, during long-term storage. The short-term heating stability at 150 and 170 degrees C for up to 20 min exhibited only minor losses (<10%) in phenolics and antioxidant capacity. Because of its high phenolic content, the phytochemical-enriched acai oil from acai fruit offers a promising alternative to traditional tropical oils for food, supplements, and cosmetic applications.

Thematic review series: Patient-Oriented Research. Dietary fat, carbohydrate, and protein: effects on plasma lipoprotein patterns

In general, under isoweight conditions, different types of dietary protein or individual amino acids have little effect on lipoprotein patterns. Dietary carbohydrate tends to increase plasma triglyceride when it displaces fat, accompanied by a decrease in HDL cholesterol concentrations. Potential differential effects of types of carbohydrate are difficult to assess because of differences in rates of absorption and confounding of dietary fiber. Saturated fatty acids increase LDL and HDL cholesterol, whereas trans fatty acids increase LDL but not HDL cholesterol. Unsaturated fatty acids decrease LDL and HDL cholesterol, polyunsaturated more so than monounsaturated. There has been considerable interest in the potential benefit of major shifts in dietary macronutrients on weight loss and lipoprotein patterns. Short-term data favor substituting protein and fat for carbohydrate, whereas long-term data have failed to show a benefit for weight loss. During an active weight loss period low-carbohydrate diets more favorably affect triglyceride and HDL and less favorably affect LDL cholesterol concentrations. Additional efforts need to be focused on gaining a better understanding of the effect of dietary macronutrient profiles on established and emerging cardiovascular disease risk factors, mechanisms for changes observed and contributors to individual variability. Such data are needed to allow reassessment and, if necessary, modification of current recommendations.

V. Adopting Healthful Lifestyle Habits to Lower LDL Cholesterol andReduce CHD Risk

V. Adopting Healthful Lifestyle Habits to Lower LDL Cholesterol andReduce CHD Risk

Lipoproteins, nutrition, and heart disease

This article reviews the current status of our knowledge of lipoproteins, nutrition, and coronary heart disease (CHD). Special emphasis is placed on CHD risk assessment, dietary intervention studies, diet-gene interactions, and current dietary guidelines and the contributions of my laboratory to these areas. CHD remains a major cause of death and disability, and risk factors include age, sex, hypertension, smoking, diabetes, elevated serum LDL cholesterol, and low HDL cholesterol. Emerging independent risk factors include elevated serum concentrations of lipoprotein(a), remnant lipoproteins, and homocysteine. The cornerstone of CHD prevention is lifestyle modification. Dietary intervention studies support the concepts that restricting saturated fat and cholesterol and increasing the intake of essential fatty acids, especially n - 3 fatty acids, reduces CHD risk. The variability in LDL-cholesterol response to diet is large, related in part to APOE and APOA4 genotype. The use of antioxidants in intervention studies has not been shown to reduce CHD risk. Compliance with dietary recommendations remains a major problem, and directly altering the food supply may be the most effective way to ensure compliance. The available data indicate that the recommendation to use fats, oils, and sugars sparingly for CHD prevention should be modified to a recommendation to use animal, dairy, and hydrogenated fats; tropical oils; egg yolks; and sugars sparingly and to increase the use of vegetables, fruit, and whole grains.