King Grub
2008-08-21, 12:04
Supplement till Journal of Nutrition, September 2008, Volume 138, Issue 9:
Nuts have been part of the diet for thousands of years. In 2003, a Qualified Health Claim was approved, stating that eating 1.5 oz (42 g) of nuts per day may reduce the risk of heart disease. Usual intakes fall short of this recommendation. About one-third of Americans report consuming nuts (tree nuts or peanuts) on any one day. Seven percent of Europeans report eating nuts, but the amount eaten by European nut consumers (31 g/d) is larger than that of Americans (21 g/d). Nuts are an excellent source of vitamin E and magnesium. Individuals consuming nuts also have higher intakes of folate, β-carotene, vitamin K, lutein+zeaxanthin, phosphorus, copper, selenium, potassium, and zinc per 1000 kcal. Regular nut consumption increases total energy intake by 250 kcal/d (1.05 MJ/d), but the body weight of nut consumers is not greater than that of nonconsumers. Nuts are an excellent source of phytochemicals (phyotsterols, phenolic acids, flavonoids, stilbenes, and carotenoids). The total phenolic constituents probably contribute to the total antioxidant capacity of nuts, which is comparable to broccoli and tomatoes. To improve guidance on the use of nuts in the diet, the position of nuts in typical food patterns needs to be addressed. The 2005 MyPyramid includes nuts in the meat and beans group. Yet, nuts are rarely consumed as meat substitutes. Because ~60% of the nuts consumed in the U.S. are eaten as snacks, emphasizing their use as a healthy snack may be more effective than inclusion within a food group.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1736S
Nuts (ground and tree) are rich sources of multiple nutrients and their consumption is associated with health benefits, including reduced cardiovascular disease risk. This has prompted recommendations to increase their consumption. However, they are also high in fat (albeit largely unsaturated) and are energy dense. The associations between these properties, positive energy balance, and body weight raise questions about such recommendations. This issue is addressed through a review of the literature pertaining to the association between nut consumption and energy balance. Epidemiological studies document an inverse association between the frequency of nut consumption and BMI. Clinical trials reveal little or no weight change with inclusion of various types of nuts in the diet over 1–6 mo. Mechanistic studies indicate this is largely attributable to the high satiety property of nuts, leading to compensatory responses that account for 65–75% of the energy they provide. Limited data suggest chronic consumption is associated with elevated resting energy expenditure resulting in dissipation of another portion of the energy they provide. Additionally, due to poor bioaccessibility, there is limited efficiency of energy absorption from nuts. Collectively, these mechanisms offset much of the energy provided by nuts. The few trials contrasting weight loss through regimens that include or exclude nuts indicate improved compliance and greater weight loss when nuts are permitted. This consistent literature suggests nuts may be included in the diet, in moderation, to enhance palatability and nutrient quality without posing a threat for weight gain.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1741S
Epidemiologic and clinical trial evidence has demonstrated consistent benefits of nut and peanut consumption on coronary heart disease (CHD) risk and associated risk factors. The epidemiologic studies have reported various endpoints, including fatal CHD, total CHD death, total CHD, and nonfatal myocardial infarct. A pooled analysis of 4 U.S. epidemiologic studies showed that subjects in the highest intake group for nut consumption had an ~35% reduced risk of CHD incidence. The reduction in total CHD death was due primarily to a decrease in sudden cardiac death. Clinical studies have evaluated the effects of many different nuts and peanuts on lipids, lipoproteins, and various CHD risk factors, including oxidation, inflammation, and vascular reactivity. Evidence from these studies consistently shows a beneficial effect on these CHD risk factors. The LDL cholesterol-lowering response of nut and peanut studies is greater than expected on the basis of blood cholesterol-lowering equations that are derived from changes in the fatty acid profile of the diet. Thus, in addition to a favorable fatty acid profile, nuts and peanuts contain other bioactive compounds that explain their multiple cardiovascular benefits. Other macronutrients include plant protein and fiber; micronutrients including potassium, calcium, magnesium, and tocopherols; and phytochemicals such as phytosterols, phenolic compounds, resveratrol, and arginine. Nuts and peanuts are food sources that are a composite of numerous cardioprotective nutrients and if routinely incorporated in a healthy diet, population risk of CHD would therefore be expected to decrease markedly.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1746S
Nuts, including peanuts, are now recognized as having the potential to improve the blood lipid profile and, in cohort studies, nut consumption has been associated with a reduced risk of coronary heart disease (CHD). More recently, interest has grown in the potential value of including nuts in the diets of individuals with diabetes. Data from the Nurses Health Study indicates that frequent nut consumption is associated with a reduced risk of developing diabetes and cardiovascular disease. Randomized controlled trials of patients with type 2 diabetes have confirmed the beneficial effects of nuts on blood lipids also seen in nondiabetic subjects, but the trials have not reported improvement in A1c or other glycated proteins. Acute feeding studies, however, have demonstrated the ability of nuts, when eaten with carbohydrate (bread), to depress postprandial glycemia. Furthermore, there was evidence of reduced postprandial oxidative stress associated with nut consumption. In terms of dietary composition, nuts have a good nutritional profile, are high in monounsaturated fatty acids (MUFA) and PUFA, and are good sources of vegetable protein. Incorporation of nuts in the diet may therefore improve the overall nutritional quality of the diet. We conclude that there is justification to consider the inclusion of nuts in the diets of individuals with diabetes in view of their potential to reduce CHD risk, even though their ability to influence overall glycemic control remains to be established.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1752S
The New and Emerging Research session highlighted the emerging understanding of both the positive and negative effects of nuts consumption on health. The limited nature of both experimental and epidemiological evidence for positive relationship(s) between nut intake and health were noted. Study inconsistency and limitations, particularly survey methodology, were explored. Recent results from epidemiologic studies indicating a potential negative association between nut and seed intake and cancer risk were reviewed. The ability of walnuts to reduce endothelin suggests an interesting biochemical mechanism of nut action that may affect other endothelin-associated diseases, which should be further explored. The effects of nuts and their constituents on a nuclear receptor screen (PPAR{alpha}, β/{delta}, {gamma}, LXR{alpha}, β, RXR{alpha}, β, {gamma}, PXR, and FXR) have been explored. Nut allergenicity and approaches necessary to minimize this effect were also described. In contrast to the positive effects, nut allergies present tree nut-allergic consumers with health challenges. The Food Allergy and Anaphylaxis Network stressed the importance of ensuring that consumers with food allergies have legible, accurate food labels. The Food Allergen Labeling and Consumer Protection Act has engendered precautionary, worst-case allergen scenario labeling statements with unknown benefits to consumer health. Issues of cross-contamination due to shared equipment and shared facilities highlighted the need to rely on allergen control programs that use ELISA technology and have increased understanding of nut allergens. Ultimately, to maximize the positive benefits of nuts, the consumer must be provided with all the information required to make an informed choice.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1757S
This article summarizes the main conclusions drawn from a conference on the health effects of nut consumption and identifies priority areas for future research. Individuals with higher intakes of nuts generally have higher intakes of many beneficial dietary constituents. More information is needed on nut composition, the bioavailability of nutrients, and other bioactive constituents. Better methods are needed to assess usual nut intake, including biomarkers, and the types, physical form, and amounts of nuts that are consumed. The feasibility of including nuts and seeds as a separate food group in the Dietary Guidelines should be tested, as should ways to increase nut intake. A moderate intake of nuts can be included in a weight loss regimen and further information is needed on whether nuts improve satiety as well as adherence to and efficacy of diets designed for weight reduction. There is substantial evidence that nut consumption reduces risk of cardiovascular disease. Future research should investigate their benefits for prevention of congestive heart failure, including clinical studies in patients with this condition, to evaluate the effects of nuts on markers of heart disease risk. Higher nut consumption is associated with lower risk of diabetes and associated cardiovascular disease. More remains to be learned about the effects of nuts on postprandial glycemic and insulin response, glycemic control, and improvement of disease risk factors in subjects with prediabetes and diabetes. Information is needed on nut-induced allergic reactions, including their prevalence and consequences, causes of sensitization, biomarkers of severe reactions, and cross-reactivity to different types of nuts.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1763S
Nuts have been part of the diet for thousands of years. In 2003, a Qualified Health Claim was approved, stating that eating 1.5 oz (42 g) of nuts per day may reduce the risk of heart disease. Usual intakes fall short of this recommendation. About one-third of Americans report consuming nuts (tree nuts or peanuts) on any one day. Seven percent of Europeans report eating nuts, but the amount eaten by European nut consumers (31 g/d) is larger than that of Americans (21 g/d). Nuts are an excellent source of vitamin E and magnesium. Individuals consuming nuts also have higher intakes of folate, β-carotene, vitamin K, lutein+zeaxanthin, phosphorus, copper, selenium, potassium, and zinc per 1000 kcal. Regular nut consumption increases total energy intake by 250 kcal/d (1.05 MJ/d), but the body weight of nut consumers is not greater than that of nonconsumers. Nuts are an excellent source of phytochemicals (phyotsterols, phenolic acids, flavonoids, stilbenes, and carotenoids). The total phenolic constituents probably contribute to the total antioxidant capacity of nuts, which is comparable to broccoli and tomatoes. To improve guidance on the use of nuts in the diet, the position of nuts in typical food patterns needs to be addressed. The 2005 MyPyramid includes nuts in the meat and beans group. Yet, nuts are rarely consumed as meat substitutes. Because ~60% of the nuts consumed in the U.S. are eaten as snacks, emphasizing their use as a healthy snack may be more effective than inclusion within a food group.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1736S
Nuts (ground and tree) are rich sources of multiple nutrients and their consumption is associated with health benefits, including reduced cardiovascular disease risk. This has prompted recommendations to increase their consumption. However, they are also high in fat (albeit largely unsaturated) and are energy dense. The associations between these properties, positive energy balance, and body weight raise questions about such recommendations. This issue is addressed through a review of the literature pertaining to the association between nut consumption and energy balance. Epidemiological studies document an inverse association between the frequency of nut consumption and BMI. Clinical trials reveal little or no weight change with inclusion of various types of nuts in the diet over 1–6 mo. Mechanistic studies indicate this is largely attributable to the high satiety property of nuts, leading to compensatory responses that account for 65–75% of the energy they provide. Limited data suggest chronic consumption is associated with elevated resting energy expenditure resulting in dissipation of another portion of the energy they provide. Additionally, due to poor bioaccessibility, there is limited efficiency of energy absorption from nuts. Collectively, these mechanisms offset much of the energy provided by nuts. The few trials contrasting weight loss through regimens that include or exclude nuts indicate improved compliance and greater weight loss when nuts are permitted. This consistent literature suggests nuts may be included in the diet, in moderation, to enhance palatability and nutrient quality without posing a threat for weight gain.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1741S
Epidemiologic and clinical trial evidence has demonstrated consistent benefits of nut and peanut consumption on coronary heart disease (CHD) risk and associated risk factors. The epidemiologic studies have reported various endpoints, including fatal CHD, total CHD death, total CHD, and nonfatal myocardial infarct. A pooled analysis of 4 U.S. epidemiologic studies showed that subjects in the highest intake group for nut consumption had an ~35% reduced risk of CHD incidence. The reduction in total CHD death was due primarily to a decrease in sudden cardiac death. Clinical studies have evaluated the effects of many different nuts and peanuts on lipids, lipoproteins, and various CHD risk factors, including oxidation, inflammation, and vascular reactivity. Evidence from these studies consistently shows a beneficial effect on these CHD risk factors. The LDL cholesterol-lowering response of nut and peanut studies is greater than expected on the basis of blood cholesterol-lowering equations that are derived from changes in the fatty acid profile of the diet. Thus, in addition to a favorable fatty acid profile, nuts and peanuts contain other bioactive compounds that explain their multiple cardiovascular benefits. Other macronutrients include plant protein and fiber; micronutrients including potassium, calcium, magnesium, and tocopherols; and phytochemicals such as phytosterols, phenolic compounds, resveratrol, and arginine. Nuts and peanuts are food sources that are a composite of numerous cardioprotective nutrients and if routinely incorporated in a healthy diet, population risk of CHD would therefore be expected to decrease markedly.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1746S
Nuts, including peanuts, are now recognized as having the potential to improve the blood lipid profile and, in cohort studies, nut consumption has been associated with a reduced risk of coronary heart disease (CHD). More recently, interest has grown in the potential value of including nuts in the diets of individuals with diabetes. Data from the Nurses Health Study indicates that frequent nut consumption is associated with a reduced risk of developing diabetes and cardiovascular disease. Randomized controlled trials of patients with type 2 diabetes have confirmed the beneficial effects of nuts on blood lipids also seen in nondiabetic subjects, but the trials have not reported improvement in A1c or other glycated proteins. Acute feeding studies, however, have demonstrated the ability of nuts, when eaten with carbohydrate (bread), to depress postprandial glycemia. Furthermore, there was evidence of reduced postprandial oxidative stress associated with nut consumption. In terms of dietary composition, nuts have a good nutritional profile, are high in monounsaturated fatty acids (MUFA) and PUFA, and are good sources of vegetable protein. Incorporation of nuts in the diet may therefore improve the overall nutritional quality of the diet. We conclude that there is justification to consider the inclusion of nuts in the diets of individuals with diabetes in view of their potential to reduce CHD risk, even though their ability to influence overall glycemic control remains to be established.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1752S
The New and Emerging Research session highlighted the emerging understanding of both the positive and negative effects of nuts consumption on health. The limited nature of both experimental and epidemiological evidence for positive relationship(s) between nut intake and health were noted. Study inconsistency and limitations, particularly survey methodology, were explored. Recent results from epidemiologic studies indicating a potential negative association between nut and seed intake and cancer risk were reviewed. The ability of walnuts to reduce endothelin suggests an interesting biochemical mechanism of nut action that may affect other endothelin-associated diseases, which should be further explored. The effects of nuts and their constituents on a nuclear receptor screen (PPAR{alpha}, β/{delta}, {gamma}, LXR{alpha}, β, RXR{alpha}, β, {gamma}, PXR, and FXR) have been explored. Nut allergenicity and approaches necessary to minimize this effect were also described. In contrast to the positive effects, nut allergies present tree nut-allergic consumers with health challenges. The Food Allergy and Anaphylaxis Network stressed the importance of ensuring that consumers with food allergies have legible, accurate food labels. The Food Allergen Labeling and Consumer Protection Act has engendered precautionary, worst-case allergen scenario labeling statements with unknown benefits to consumer health. Issues of cross-contamination due to shared equipment and shared facilities highlighted the need to rely on allergen control programs that use ELISA technology and have increased understanding of nut allergens. Ultimately, to maximize the positive benefits of nuts, the consumer must be provided with all the information required to make an informed choice.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1757S
This article summarizes the main conclusions drawn from a conference on the health effects of nut consumption and identifies priority areas for future research. Individuals with higher intakes of nuts generally have higher intakes of many beneficial dietary constituents. More information is needed on nut composition, the bioavailability of nutrients, and other bioactive constituents. Better methods are needed to assess usual nut intake, including biomarkers, and the types, physical form, and amounts of nuts that are consumed. The feasibility of including nuts and seeds as a separate food group in the Dietary Guidelines should be tested, as should ways to increase nut intake. A moderate intake of nuts can be included in a weight loss regimen and further information is needed on whether nuts improve satiety as well as adherence to and efficacy of diets designed for weight reduction. There is substantial evidence that nut consumption reduces risk of cardiovascular disease. Future research should investigate their benefits for prevention of congestive heart failure, including clinical studies in patients with this condition, to evaluate the effects of nuts on markers of heart disease risk. Higher nut consumption is associated with lower risk of diabetes and associated cardiovascular disease. More remains to be learned about the effects of nuts on postprandial glycemic and insulin response, glycemic control, and improvement of disease risk factors in subjects with prediabetes and diabetes. Information is needed on nut-induced allergic reactions, including their prevalence and consequences, causes of sensitization, biomarkers of severe reactions, and cross-reactivity to different types of nuts.
http://jn.nutrition.org/cgi/content/full/138/9S-I/1763S