Ternus, M., K. Lapsley, K. McMahon, G. Johnson, 2006. Qualified health claim for nuts and heart disease prevention, development of consumer-friendly language. Nutrition Today. 41(2):62-66.
In 2003, the US Food and Drug Administration (FDA) began authorizing qualified health claims for conventional foods. Although the FDA had developed generic qualifying language for these claims, the language had not yet been tested with consumers. A shopping mall intercept was conducted among a random sample of 408 adults. The research tested consumer preference, understanding and believability, and impact on nut consumption of 4 variations of the ‘‘B’’ level qualified health claim for nuts and heart disease. The FDA generic language was used as the control. The results show that one of the alternatives was ranked significantly higher than the FDA generic claim for clarity and understandability but was similar in all other categories, including the scientific uncertainty associated with the claim. This research demonstrates that it is possible to meet FDA’s standards for truthful and not misleading health claims using consumer-friendly language.
Serra-Majem, L., B. Roman, R. Estruch, 2006. Scientific evidence of interventions using the Mediterranean diet: A systematic review. Nutrition Reviews. 64(2):S27-S47.
The Mediterranean Diet has been associated with greater longevity and quality of life in epidemiological studies, the majority being observational. The application of evidence-based medicine to the area of public health nutrition involves the necessity of developing clinical trials and systematic reviews to develop sound recommendations. The purpose of this study was to analyze and review the experimental studies on Mediterranean diet and disease prevention. A systematic review was made and a total of 43 articles corresponding to 35 different experimental studies were selected. Results were analyzed for the effects of the Mediterranean diet on lipoproteins, endothelial resistance, diabetes and antioxidative capacity, cardiovascular diseases, arthritis, cancer, body composition, and psychological function. The Mediterranean diet showed favorable effects on lipoprotein levels, endothelium vasodilatation, insulin resistance, metabolic syndrome, antioxidant capacity, myocardial and cardiovascular mortality, and cancer incidence in obese patients and in those with previous myocardial infarction. Results disclose the mechanisms of the Mediterranean diet in disease prevention, particularly in cardiovascular disease secondary prevention, but also emphasize the need to undertake experimental research and systematic reviews in the areas of primary prevention of cardiovascular disease, hypertension, diabetes, obesity, infectious diseases, age-related cognitive impairment, and cancer, among others. Interventions should use food scores or patterns to ascertain adherence to the Mediterranean diet. Further experimental research is needed to corroborate the benefits of the Mediterranean diet and the underlying mechanisms, and in this sense the methodology of the ongoing PREDIMED study is explained.
Salas-Salvado’, J., M. Bullo’, A. Pe’rez-Heras, E. Ros, 2006. Dietary fiber, nuts and cardiovascular diseases. British Journal of Nutrition. 96, Suppl. 2, S45-S51.
Dietary fiber has a range of metabolic health benefits. Through a variety of mechanisms, dietary fiber, and the viscous variety in particular, slows down gastric emptying and intestinal transit, decreases the rate of intestinal carbohydrate absorption, and increases fecal bile acid excretion. Therefore, consumption of some types of soluble fiber can enhance satiety, which is associated with a lower BMI, and reduce blood cholesterol and the postprandial glucose response. Surprisingly, the consumption of insoluble fiber from whole grains, though metabolically inert, has been associated with a reduction in the risk of developing coronary heart disease and diabetes in epidemiological studies. The likely reason is that whole grains, like nuts, legumes and other edible seeds, contain many bioactive phytochemicals and various antioxidants. After cereals, nuts are the vegetable foods that are richest in fiber, which may partly explain their benefit on the lipid profile and cardiovascular health.
Kocyigit, A., A.A. Koylu, H. Keles, 2006. Effects of pistachio nuts consumption on plasma lipid profile and oxidative status in healthy volunteers. Nutrition, Metabolism & Cardiovascular Diseases. 16:202-9.
Background and aim: Effects of pistachio nuts consumption on plasma lipid profile and oxidative status were investigated in healthy volunteers with normal lipid levels. Methods and results: The study was conducted in 24 healthy men and 20 healthy women. All subjects consumed their regular diets during a 1-week period. After this period, half of the subjects (12 men and 10 women, mean age 32.8 ± 6.7 years) were randomized to a regular diet group and the other half (12 men and 10 women, mean age 33.4 ± 7.2 years) were randomized to a pistachio group which involved substituting pistachio nuts for 20% of their daily caloric intake for 3 weeks. Plasma total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride, malondialdehyde (MDA) and antioxidant potential (AOP) were measured before and after the dietary modification from all the subjects. After 3 weeks, with the pistachio diet, the mean plasma total cholesterol, MDA levels and, total cholesterol/ HDL and LDL/HDL ratios were found to be significantly decreased (P 0.05). Conclusion: These results indicated that consumption of pistachio nuts decreased oxidative stress, and improved total cholesterol and HDL levels in healthy volunteers.
Brufau, G., J. Boatella, M. Rafecas, 2006. Nuts: source of energy and macronutrients. British Journal of Nutrition. 96, Suppl. 2, S24-S28.
On the basis of the high fat content of nuts, they are traditionally considered as foods that provide a high amount of energy. However, epidemiologic and clinical observations do not indicate an association between nut intake and increased BMI. There is a notorious variability in macronutrient composition among nuts, although they have some consistent patterns. Nuts contain all major macronutrients: protein, carbohydrate, and fat. The total protein content is relatively high, which makes them a good source of plant protein (especially for vegetarians). Although nuts contain low amounts of some essential amino acids, this is not a nutritional concern due to the complement of protein. In addition, nuts have a low lysine:arginine ratio, which is inversely associated with the risk of developing hypercholesterolemia and atherosclerosis. Carbohydrates are the second highest macronutrient in nuts in terms of total calories provided. The fat fraction is characterized by a high amount of unsaturated fatty acids and a low content of saturated fatty acids. In conclusion, the high content in unsaturated fatty acids, the low lysine:arginine ratio, and the presence of other bioactive molecules (such as fiber, phytosterols, vitamin and other antioxidants, and minerals) make the addition of nuts to healthy diets a useful tool for the prevention of cardiovascular heart diseases.
Ros, E., J. Mataix, 2006. Fatty acid composition of nuts – implications for cardiovascular health. British Journal of Nutrition. 96, Suppl. 2, S29-S35.
It is well established that, due to their high content of saturated fatty acids (SFA), the intake of meat and meat products is strongly associated with elevated blood cholesterol concentrations and an increased risk of hypertension, diabetes and cardiovascular diseases. Conversely, the intake of foods rich in unsaturated fatty acids, such as those contained in most vegetable fats and oils and oily fish, is associated with improved lipid profiles, a lower potency of intermediate biomarkers of atherosclerosis and lesser incidence of cardiovascular diseases. There are persuasive evidences that dietary substitution of monounsaturated fatty acids (MUFA) or n-6 polyunsaturated fatty acids (PUFA) for SFA lowers blood cholesterol and may have beneficial effects on inflammation, thrombosis, and vascular reactivity. MUFA may have an advantage over PUFA because enrichment of lipoprotein lipids with MUFA increases their resistance to oxidation. Marine n-3 PUFA have a number of anti-atherosclerotic effects, including anti-arrhythmic properties and, at relatively high doses, reduce serum triglycerides. These effects appear to be shared in part by vegetable n-3 PUFA. Nuts are natural foods rich in unsaturated fatty acids; most nuts contain substantial amounts of MUFA, while walnuts are especially rich in both n-6 and n-3 PUFA. Healthy fats in nuts contribute to the beneficial effects of frequent nut intake observed in epidemiological studies (prevention of coronary heart disease, diabetes, and sudden death) and in short-term feeding trials (cholesterol lowering, LDL resistance to oxidation, and improved endothelial function).
Kurlandsky, S.B., K.S. Stote, 2006. Cardioprotective effects of chocolate and almond consumption in healthy women. Nutr. Res. 26:509-516.
The primary objective of this study was to identify potentially synergistic or additive effects of combining consumption of dark chocolate with almonds as part of a low-fat diet on circulating levels of serum lipids and inflammatory markers: intercellular adhesion molecule (ICAM), vascular adhesion molecule, and high-sensitivity C-reactive protein. A 6-week, 4-armed parallel design was used; 49 healthy normocholesterolemic women participated. Subjects were randomized to 1 of 3 treatments: chocolate (41 g/d), almonds (60 g/d), chocolate and almonds, or control (no chocolate or almonds). All subjects followed the National Cholesterol Education Program Therapeutic Lifestyle Changes diet. All subjects improved dietary intakes in accordance with guidelines, and no subjects gained or lost weight. Serum cholesterol concentrations showed no changes after 6 weeks; however, triacylglycerol levels were reduced by approximately 21%, 13%, 19%, and 11% ( P < .05), in the chocolate, almond, chocolate and almond, and control groups, respectively. Circulating ICAM levels decreased significantly by 10% in the treatment group consuming chocolate only (P = .027). No significant changes were observed for vascular adhesion molecule and high-sensitivity C-reactive protein levels in any treatment group. No synergistic or additive effects were observed when both products were consumed. In conclusion, consumption of chocolate and almonds as part of the Therapeutic Lifestyle Changes diet for 6 weeks showed no harmful effects in healthy women; all dietary modifications improved serum triacylglycerol levels, and consumption of chocolate reduced levels of circulating ICA
Kelly Jr., J.H., J. Sabaté’, 2006. Nuts and coronary heart disease: an epidemiological perspective. British Journal of Nutrition. 96, Suppl. 2, S61-S67
The epidemiological evidence for the cardio-protective effect of nut consumption is presented and reviewed. Four large prospective epidemiological studies of primary prevention of coronary heart disease are reviewed and discussed (Adventist Health Study, Iowa Women’s Health Study, Nurses’ Health Study and the Physicians’ Health Study). Other studies of nuts and coronary heart disease risk are addressed. The combined evidence for a cardio-protective effect from nut consumption is summarized and presented graphically. The risk of coronary heart disease is 37% lower for those consuming nuts more than four times per week compared to those who never or seldom consume nuts, with an average reduction of 8·3% for each weekly serving of nuts. The evidence for a causal relationship between nut consumption and reduced risk of coronary heart disease is outlined using Hill’s criteria for causality and is found to support a causal cardio-protective relationship.
Jiang, R., D.R. Jacobs, Jr., E. Mayer-Davis, M. Szkio, D. Herrington, N.S. Jenny, R. Kronmal, R. G. Barr, 2006. Nut and seed consumption and inflammatory markers in the multi-ethnic study of atherosclerosis. Am J Epidemiol. 163:222-231.
Nuts and seeds are rich in unsaturated fat and other nutrients that may reduce inflammation. Frequent nut consumption is associated with lower risk of cardiovascular disease and type 2 diabetes. The authors examined associations between nut and seed consumption and C-reactive protein, interleukin-6 and fibrinogen in the Multi-Ethnic Study of Atherosclerosis. This 2000 cross-sectional analysis included 6,080 US participants aged 45-84 years with adequate information on diet and biomarkers. Nut and seed consumption was categorized as never/rare, less than once/week, 1-4 times/week and five or more times/week. After adjustments for age, gender, race/ethnicity, site, education, income, smoking, physical activity, use of fish oil supplements, and other dietary factors, mean biomarker levels in categories of increasing consumption were as follows: C-reactive protein-1.98, 1.97, 1.80, and 1.72 mg/liter, interleukin-6 – 1.25, 1.24, 1.21 and 1.15 pg/ml; and fibrinogen-343, 338, 338, and 331 mg/dl (all p’s for trend < 0.01). Further adjustment for hypertension, diabetes, medication use, and lipid levels yielded similar results. Additional adjustment for body mass index moderately attenuated the magnitude of the associations, yielding borderline statistical significance. Associations of nut and seed consumption with these biomarkers were not modified by body mass index, waist:hip ratio, or race/ethnicity. Frequent nut and see consumption was associated with lower levels of inflammatory markers, which may partially explain the inverse association of nut consumption with cardiovascular disease and diabetes risk.
Griel, A.E., P.M. Kris-Etherton, 2006. Tree nuts and the lipid profile: a review of clinical studies. British Journal of Nutrition. 96, Suppl. 2, S68-S78
Tree nuts have a fatty acid profile that favorably affects blood lipids and lipoproteins. They are low in saturated fat and high in unsaturated fatty acids and are rich sources of other nutrients. An extensive database consistently shows total and LDL cholesterol-lowering effects of diets low in saturated fat and cholesterol and high in unsaturated fat provided by a variety of tree nuts. Collectively, a summary of studies conducted to date shows that tree nuts reduce LDL cholesterol by 3-19% compared with Western and lower-fat diets. Nuts also contain many nutrients and bioactive compounds that appear to contribute to the favorable effects on lipids and lipoproteins – these include plant sterols, dietary fiber and antioxidants. Because of their unique nutrient profile, nuts can be part of a diet that features multiple heart-healthy foods resulting in a cholesterol lowering response that surpasses that of cholesterol-lowering diets typically used to reduce CVD risk.
