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Background: Plasma lipoproteins may be classified by their apolipoprotein composition. The lipoprotein subclass containing apolipoproteins B and C (LpB:C) is considered the most atherogenic. Objective: We evaluated the acute effects of individual fatty acids on apolipoprotein B (apo B)-containing lipoproteins in adults with type 2 diabetes (n = 15). Design: We administered 3 meals in a randomized, double-blind, crossover design. Treatments contained skim milk and 50 g fat from high-oleic acid safflower and canola oils (monounsaturated fatty acid; MUFA), MUFA + 3.5 g α-linolenic acid (ALA; MUFA + ALA) from high-ALA canola oil, or MUFA + 4.0 g both eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA; MUFA + EPA/DHA) from sardine oil. Apo B, LpB, LpB:C, LpB:E + LpB: C:E, and LpA-II:B:C:D:E were measured at baseline and 2 and 4 h after the meal. Flow-mediated dilation was measured at baseline and 4 h after the meal. Results: The treatments significantly increased apo B and LpB post-prandially (P < 0.03 for both), but the magnitude of the changes did not differ significantly between the treatments. The postprandial change in LpB:C was 23% lower after MUFA + EPA/DHA than after MUFA (treatment X time interaction, P < 0.0001). MUFA + ALA attenuated the increase in LpA-II:B:C:D:E in those with high triacylglycerols (≥ 1.69 mmol/L) but was the only treatment to significantly increase this particle in those with low triacylglycerols (treatment X group interaction, P < 0.0001). Examination of change scores did not reveal the source of the interaction of treatment and time (P < 0.007) for LpB:E + LpB:C:E. Furthermore, the subjects with the largest increases in LpB:C exhibited the largest impairment in endothelial function. Conclusions: The results suggest that unsaturated fatty acids differentially affect concentrations of apo B-containing lipoprotein subclasses. A rise in LpB:C adversely affects endothelial function. Meals containing MUFA + EPA/DHA attenuated the postprandial rise in LpB:C and the impairment of endothelial function.

Epidemiologic studies have shown a beneficial association between polyunsaturated fatty acid (PUFA), specifically linoleic acid (C18:2, n-6), intake and cardiovascular disease morbidity and mortality. Clinical studies have shown that n-6 PUFAs have the most potent cholesterol-lowering effects of the individual fatty acid classes, and emerging evidence suggests that PUFAs have favorable effects on postprandial lipemia. However, some studies suggest that high intakes of linoleic acid may have adverse effects on proinflammatory cytokines and adhesion molecules. Research is needed to establish the optimal level of dietary PUFAs that maximally affects the greatest number of health risk factors.

"Bioactive compounds" are extranutritional constituents that typically occur in small quantities in foods. They are being intensively studied to evaluate their effects on health. The impetus sparking this scientific inquiry was the result of many epidemiologic studies that have shown protective effects of plant-based diets on cardiovascular disease (CVD) and cancer. Many bioactive compounds have been discovered. These compounds vary widely in chemical structure and function and are grouped accordingly. Phenolic compounds, including their subcategory, flavonoids, are present in all plants and have been studied extensively in cereals, legumes, nuts, olive oil, vegetables, fruits, tea, and red wine. Many phenolic compounds have antioxidant properties, and some studies have demonstrated favorable effects on thrombosis and tumorogenesis and promotion. Although some epidemiologic studies have reported protective associations between flavonoids or other phenolics and CVD and cancer, other studies have not found these associations. Various phytoestrogens are present in soy, but also in flaxseed oil, whole grains, fruits, and vegetables. They have antioxidant properties, and some studies demonstrated favorable effects on other CVD risk factors, and in animal and cell culture models of cancer. However, because phytoestrogens act both as partial estrogen agonists and antagonists, their effects on cancer are likely complex. Hydroxytyrosol, one of many phenolics in olives and olive oil, is a potent antioxidant. Resveratrol, found in nuts and red wine, has antioxidant, antithrombotic, and anti-inflammatory properties, and inhibits carcinogenesis. Lycopene, a potent antioxidant carotenoid in tomatoes and other fruits, is thought to protect against prostate and other cancers, and inhibits tumor cell growth in animals. Organosulfur compounds in garlic and onions, isothiocyanates in cruciferous vegetables, and monoterpenes in citrus fruits, cherries, and herbs have anticarcinogenic actions in experimental models, as well as cardioprotective effects. In summary, numerous bioactive compounds appear to have beneficial health effects. Much scientific research needs to be conducted before we can begin to make science-based dietary recommendations. Despite this, there is sufficient evidence to recommend consuming food sources rich in bioactive compounds. From a practical perspective, this translates to recommending a diet rich in a variety of fruits, vegetables, whole grains, legumes, oils, and nuts.

Barley contains high levels of soluble dietary fibre, including mixed linked 1→3, 1→4β-D-glucans (β-glucan). An extract of β-glucan from waxy, hulless barley containing 56% total dietary fibre (TDF) was incorporated into flour tortillas, cornstarch pudding and apple granola bars to provide 2 g soluble fibre as β-glucan per serving. The foods were tested for objective functional properties. Flour tortillas with β-glucan were incorporated into rat diets and compared to diets containing an equivalent amount of cellulose, to test the fibre effect on growth and lipid metabolism parameters. Rats fed β-glucan tortillas had lower feed consumption and body weight (P 0·05). Plasma LDL-cholesterol of rats fed β-glucan was lower (P 0·05). Rats fed β-glucan tortillas had higher (P

Background: The perception that all high-fat snacks are unhealthy may be wrong. Objective: We aimed to assess whether replacing low-fat and highfat snacks with snacks rich in polyunsaturated fatty acids (PUFAs) and low in saturated andtrans fatty acids would improve cardiovascular health. Design: Thirty-three adults participated in a randomized crossover trial of 3 controlled feeding phases of 25 d each in which a different type of snack was provided: low-fat (30.8% of energy from fat, 5.2% of energy from PUFAs), high-PUFA (36.3% of energy from fat, 9.7% of energy from PUFAs), or high-fat (37.9% of energy from fat, 5.8% of energy from PUFAs) snack. Results: Each diet reduced LDL- and total cholesterol concentrations, but reductions were greater with the low-fat and the highPUFA diets than with the high-fat diet: LDL cholesterol (11.8% and 12.5% compared with 8.8%, respectively; P 0.03 and 0.01), total cholesterol (10.5% and 10.7% compared with 7.9%, respectively; P 0.03 and 0.02). The high-PUFA diet tended to reduce triacylglycerol concentrations (9.4%; P 0.06), and this change was greater than that with the low-fat (P 0.028) and high-fat (P 0.0008) diets. Conclusions: These data show that snack type affects cardiovascular health. Consuming snack chips rich in PUFA and low in saturated ortrans fatty acids instead of high-saturated fatty acid andtrans fatty acid or low-fat snacks leads to improvements in lipid profiles concordant with reductions in cardiovascular disease risk. Am J Clin Nutr 2007;85:1503–10.

We examined the acute postprandial effects of meals containing unsaturated fatty acids on flow-mediated dilation (FMD) of the brachial artery and triacylglycerols in individuals with type 2 diabetes. We hypothesised that consumption of omega-3 fatty acids would enhance vascular function. Saturated fat reduces FMD for several hours, but there is inconsistent evidence about whether foods containing unsaturated fats impair FMD acutely. Little is known about the acute effects of omega-3 fatty acids on vascular reactivity.We measured FMD before and 4 h after 3 test meals (50 g fat, 2,615 kJ) in 18 healthy adults with type 2 diabetes. The monounsaturated fatty acids (MUFA) meal contained 50 g fat from high oleic safflower and canola oils. Two additional meals were prepared by replacing 7% to 8% of MUFA with docosahexaenoic acid and eicosapentaenoic acid from sardine oil or alpha-linolenic acid from canola oil.In the sample as a whole, FMD was increased 17% at 4 h vs. the fasting baseline. After the MUFA meal, subjects with the largest increases in triacylglycerols had the largest FMD decreases. The opposite pattern was observed after meals containing docosahexaenoic acid and eicosapentaenoic acid or alpha-linolenic acid. In subjects with high fasting triacylglycerols, meals containing 3 to 5 g of omega-3 fatty acids increased FMD by 50% to 80% and MUFA alone had no significant effects on FMD.Endothelium-dependent vasodilation was not impaired 4 h after meals containing predominantly unsaturated fatty acids. The fatty acid composition of the meal and the metabolic status of the individual determine the vascular effects of a high-fat meal.

Aims/hypothesis. Dysfunction of the vascular endothelium is commonly observed in Type 2 diabetes, and endothelial function may be an important outcome for clinical trials in diabetic samples. However, the most commonly used non-invasive test of endothelial function (flow-mediated dilation [FMD]) is technically challenging to perform, and no previous studies have carefully examined the reproducibility of FMD measurements in individuals with Type 2 diabetes. In this study, we tested the hypothesis that larger day-to-day changes in insulin and glucose are associated with larger fluctuations in FMD. Methods. Ultrasound was used to measure the FMD (% change from baseline diameter) of the brachial artery in 18 healthy adults with Type 2 diabetes on three separate occasions, in the absence of changes to diet, activity level or medications. The CV and mean deviations between pairs of FMD scores in the same individual were used as the primary outcome variables. Results. The CV for FMD (29.7%) was higher than the level traditionally accepted for biochemical assays. However, this CV estimate is within the low range of published values for FMD in healthy individuals. FMD scores were not significantly correlated with glucose or insulin levels. However, subjects with the largest variability in FMD also showed the largest fluctuations in glucose (r=0.52), insulin (r=0.47) and heart rate (r=0.48) (p≤0.05). Conclusions/interpretation. FMD can be reliably measured in individuals with Type 2 diabetes, and population-specific data on reliability is critical for the design of adequately powered studies of endothelial function.

For the first time, Dietary Reference Intakes (DRIs) for macronutrients have been established by the National Academies’ Institute of Medicine for the United States and Canada (1). This science-based report makes new recommendations for energy, carbohydrates, fiber, fat, fatty acids, cholesterol, protein, and amino acids. The DRI Report embraces the philosophy of making dietary recommendations that assure a nutritionally adequate diet, promote good health, prevent chronic disease, and avoid overconsumption. Recommendations suggest that adults should consume a diet that provides 45% to 65% of their calories from carbohydrates, 10% to 35% from protein, and 20% to 35% from fat. The report advises that saturated fat, trans fat, and cholesterol be as low as possible. Because polyunsaturated fatty acids (PUFAs) are essential nutrients, the DRI Report recommends 17 g/d for men and 12 g/d for women of linoleic acid (C 18:2), an omega-6 PUFA. For cs-linolenic acid (ALA), an omega-3 fatty acid, 1.6 and 1.1 g/d should be consumed by men and women, respectively. The recommendations for PUFA are based on average intakes in the United States. For simplicity, the report recommends that 5% to 10% of calories come from PUFA and 0.6% to 1.2% come from ALA. Importantly, approx 10% of omega-3 fatty acid intake can come from long-chain, highly unsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Because of the total fat recommendation and the guidance provided about saturated fat, trans fat, and PUFA intake, the balance will be derived from monounsaturated fatty acids (MUFAs). The range of total fat from 20% to 35% of calories recognizes that healthy diets can be planned over a reasonably broad range of fat intake, as long as saturated fat, trans fat, and cholesterol are kept as low as possible. This range in total fat reflects the health benefits of unsaturated fat in the context of a nutritionally adequate diet that promotes a healthy weight. The range of all macronutrients acknowledges that there are many healthy diets with respect to macronutrient profiles, as long as each diet meets the specific recommendations made in the DRI Report for saturated fat, trans fat, cholesterol, total fiber (38 g/d for men and 25 g/d for women), and added sugar (a maximum of 25% or fewer calories from added sugars).

A growing body of research offers insight into the influence of dietary protein on cardiovascular disease (CVD) risk. Early studies in rabbits indicated that animal protein was atherogenic; however, this has not been demonstrated in other animals species (pig, primate) or humans. More recent studies have found that low-fat animal protein can effectively improve some CVD risk factors. Soy protein has received much attention in recent years due to its seemingly marked effect on plasma cholesterol levels. However, further research has shown the hypocholesterolemic effect of soy protein to be most pronounced in cases of moderate to severe elevations in plasma lipids. Still, animal and soy protein sources contain a variety of bioactive components that may offer protection above and beyond cholesterol reduction. This review provides evidence that as part of a low-saturated fat diet, animal and/or soy protein intake at or above the recommended intake level of 15% of total calories lowers plasma cholesterol levels, reduces blood pressure, and potentially facilitates healthy weight management.

Cardiovascular disease (CVD) is the leading cause of death in the United States accounting for more deaths than all other causes combined. Numerous risk factors for CVD are identified, many of which are modifiable by diet and lifestyle practices. Major modifiable risk factors include cigarette smoking, elevated total and low-density lipoprotein (LDL) cholesterol levels, overweight and obesity, hypertension, diabetes mellitus, and a sedentary lifestyle. Other important risk factors that are modifiable by diet are a low level of high-density lipoprotein cholesterol, elevated levels of triglycerides, lipoprotein, insulin, hypertension, altered hemostatic factors, and small, dense LDL particles. This chapter reviews the understanding of how changes in the macronutrient profile of the diet affect CVD risk status. It describes various low saturated fatty acids (SFA) and cholesterol diets that differ in macronutrient content and present the plasma lipid and lipoprotein responses that are reported for these diets. This, chapter highlights the effect of various low SFA , low-cholesterol diet options with differentmacronutrient profiles on newly defined CVD risk factors.

Overwieght and obesity are classified as a major risk for cardiovascular disease (CVD). An increase in the body mass index is associated with adverse changes in the plasma lipid and lipoprotein profile resulting in elevated total cholesterol, low-density lipoprotein-cholesterol, and triglyceride levels and a decrease in high-density lipoprotein levels. An android pattern of obesity is associated with a more deleterious plasma lipoprotein profile as well as hypertension and insulin resistance, resulting in an even greater increase in CVD risk. Weight loss through caloric restriction improves the plasma lipoprotein profile. A Step-1 diet plus exercise confer even greater benefits.