Progress 03/20/09 to 03/19/14
Outputs
Progress Report Objectives (from AD-416): 1. Using an epidemiologic approach, investigate the role of whole grains, selected nutrients, other bioactive food components, and healthy dietary patterns in preventing the development of age-related conditions such as type 2 diabetes mellitus, cardiovascular disease, cancer, musculoskeletal disorders and age-related eye disease. 2. Determine the validity of biomarkers for whole grain intake, their use in assessing relationships between whole grain intake and disease risk, and the relationship between these biomarkers and insulin resistance phenotypes. 3. Using an epidemiologic approach, examine determinants of adherence to the recommended dietary patterns in the Dietary Guidelines for Americans (DGA) and the relation between adherence to these patterns and prevention of age-related weight gain, abdominal obesity, and related metabolic disorders such as inflammation, endothelial dysfunction and insulin resistance. 4. Using an epidemiologic approach, investigate safe upper limits for the dietary intake of folic acid. 5. Using an epidemiologic approach, determine relationships between dietary intake and nutrient status and the prevention of age-related cognitive decline in humans. 6. Using an epidemiologic approach, investigate the role of nutritional factors in limiting the cormorbidities such as CVD and premature mortality in individuals with chronic kidney disease (CKD). Approach (from AD-416): Many age-related conditions, such as cardiovascular disease, diabetes, dementia, cancer, musculoskeletal disorders and age-related eye disease, appear to have strong nutritional components. Improved nutrition through public health recommendations and interventions could have a tremendous impact on the economic and societal costs associated with these disabilities, but development of recommendations and interventions requires a greater understanding of the presumptive role that nutrition plays in delaying the onset of disease and disability. Epidemiologic methods applied to community-based investigations of aging populations provide a valuable tool to help meet this need. We will use these methods to address project objectives. Our research on nutrition and risk of obesity and metabolic and chronic disease (Objective 1) included projects related to weight, metabolic disorder, diabetes and cardiovascular disease risk. As part of our research on the relation between diet and weight, we showed that sugar- sweetened beverage consumption is associated with greater amounts of abdominal visceral fat tissue, an important risk factor for cardiovascular and other metabolic diseases. As part of our research on the relation between diet and metabolic disease, we demonstrated that metabolically abnormal individuals, whether lean, overweight and obese, consumed more sugar-sweetened beverages than metabolically normal individuals with similar body weights. We also reported that higher magnesium intake reduces the risk of impaired glucose and insulin metabolism, and progression from prediabetes to diabetes in middle-aged Americans. We have also initiated studies of the relationships between sugar-sweetened beverage consumption and accumulation of liver fat and development of nonalcoholic fatty liver disease. As part of our research on the relation between diet and cardiovascular disease, we observed that higher magnesium intake is associated with less coronary artery calcification (a relatively novel and strong determinant of cardiovascular disease), and that the inverse relationship between statin use and cholesterol was enhanced among those consuming greater amounts of whole grains. As part of our studies of health benefits of dairy intake, we observed that higher total dairy intake was associated with a slower age-related increase in systolic blood pressure and a lower incidence of hypertension, and greater consumption of low-fat/fat free dairy was associated with a smaller increase in diastolic blood pressure. We also identified genetic mutations involved in methionine and homocysteine metabolism and examined their potential to affect risk of heart disease and stroke. In one study, we identified several novel loci that influence plasma homocysteine concentration, a product of the folate one- carbon metabolic pathway that is consistently associated with increased CVD risk. However, these genetic variants were not associated with risk of coronary artery disease. In a second study, we characterized genetic risk factors associated with the folate one-carbon pathway and demonstrated that the genetic modifications in a gene key to folate metabolism were strongly associated with risk of stroke. Our progress on characterizing the role of nutrition in risk of age-related disease is crucial in identifying potential interventions aimed at maintaining health as we age. As part of our work of identifying biomarkers for whole grain consumption (Objective 2), we conducted a pilot whole wheat feeding trial to see if whole wheat consumption, which is rich in prebiotics (dietary fibers that are believed to enhance the growth of beneficial gut bacteria) can modify the types and proportions of gut bacteria. The small pilot study size and the large intra- and inter-person variation during the course of the study limited our ability to identify any effects of the whole wheat intervention. For example, the frequency of one of the most common gut bacterial taxa, Bacteriodetes, varied by as much as an order of magnitude in one week within some individuals, yet remained relatively unchanged during the four week study in others. Understanding the effect of diet on the human gut microbiome may have tremendous health benefits based on the growing evidence that the types of gut bacteria may influence aspects of health from inflammatory bowel disease to weight gain. As part of our work examining the benefits of adherence to the Dietary Guidelines for Americans and other health eating patterns (Objective 3), we revised our Dietary Guidelines for Americans Adherence Index (DGAI) to conform to the 2010 DGA recommendations and used this score to demonstrate in preliminary analyses that Americans with diets that are more consistent with dietary recommendations had reduced risk of inflammation. It is now recognized that chronic inflammation is a major underlying factor in many age-related pathological processes, and our work on dietary recommendations and inflammation suggests that simple dietary changes improving adherence to current government recommendations could improve the outlook for healthy aging. As part of our research on B vitamins and cognitive function (Objective 5), we completed the data analysis from a randomized trial of B vitamin supplementation and cognitive function and have drafted the primary results manuscript that explores the effects of B vitamin supplements on age-related cognitive changes. Our accomplishments related to this objective should help us better understand the role of nutrition in preventing age-related cognitive decline. Accomplishments 01 NUTRITIONAL EPIDEMIOLOGY: Higher sugar-sweetened beverage (SSB) consumption is related to greater visceral adiposity. Abdominal adiposity, particularly visceral adipose tissue (VAT), is independently linked to the pathogenesis of diabetes and cardiovascular disease. Emerging evidence suggests that greater intake of sugar-sweetened beverages (SSB) may be associated with abnormal fat accumulation in VAT. ARS funded researchers at JMUSDA-HNRCA at Tufts University in Boston, Massachusetts, conducted a cross-sectional analysis in 2,596 middle- aged adults (1,306 men and 1,290 women) from the Framingham Heart Study Offspring and the Third Generation cohorts observing that daily consumption of SSB was associated with a greater VAT volume, whereas consumption of diet soda was not associated with VAT volume. 02 NUTRITIONAL EPIDEMIOLOGY: Sugar-sweetened beverage (SSB) consumption increases metabolic risk. Some obese individuals, known as the �metabolically healthy obese (MHO)� appear to be protected from developing metabolic abnormalities typically associated with obesity and may be at lower risk of chronic disease whereas some normal weight individuals display metabolic abnormalities typically seen in obese populations (i.e. �metabolically obese normal weight (MONW)� individuals). Little is known about differences in dietary intake in these two metabolic phenotypes. ARS funded researchers at JMUSDA-HNRCA at Tufts University in Boston, Massachusetts, conducted the first cross- sectional study examining SSB consumption and MHO and MONW phenotypes. Our findings suggest that MHO individuals consume less SSB than metabolically abnormal obese individuals, and that normal weight individuals are more likely to express the MONW phenotype as SSB consumption increases. 03 NUTRITIONAL EPIDEMIOLOGY: Magnesium intake is associated with less arterial calcification. Coronary artery calcification (CAC) and abdominal aortic calcification (AAC) are measures of advanced atherosclerosis that predict cardiovascular disease (CVD) morbidity and mortality independently of traditional CVD risk factors. Dietary magnesium, found in a broad range of foods including whole grains, green leafy vegetables, almonds, coffee, and dark chocolate, has been linked to many aspects of cardiovascular health and a lower risk of stroke, myocardial infarction and other CVD outcomes. This mineral may lower CVD risk through a role in preventing vascular calcification. The aim of this study by ARS funded researchers at JMUSDA-HNRCA at Tufts University in Boston, Massachusetts, was to examine whether higher magnesium intake was associated with lower CAC and AAC in participants of the Framingham Heart Study who were free of cardiovascular disease and underwent Multi-Detector Computed Tomography of the heart and abdomen (n = 2,695; age: 53 +/- 11 years). The odds of having any CAC were 58% lower in those with the highest compared to those with the lowest magnesium intake.
Impacts
(N/A)
Publications
- Wang, H., Troy, L.M., Rogers, G.T., Fox, C.S., Mckeown, N.M., Meigs, J.B., Jacques, P.F. 2014. Longitudinal association between dairy consumption and changes of body weight and waist circumference: the Framingham Heart Study. International Journal of Obesity. 38(2):299-305. DOI:10.1038/ijo.2013.78.
- Makarem, N., Scott, M., Quatromoni, P., Jacques, P., Parekh, N. 2014. Trends in dietary carbohydrate consumption from 1991 to 2008 in the Framingham Heart Study Offspring Cohort. British Journal of Nutrition. DOI:10.1017/S0007114513004443.
- Green, A.K., Jacques, P.F., Rogers, G., Fox, C.S., Meigs, J.B., Mckeown, N. M. 2014. Sugar-sweetened beverages and prevalence of the metabolically abnormal phenotype in the Framingham Heart Study. Obesity. 22(5):E157-163. DOI:10.1002/oby.20724.
- Mccullough, M.L., Peterson, J.J., Patel, R., Jacques, P.F., Shah, R., Dwyer, J.T. 2012. Flavonoid intake and cardiovascular disease mortality in a prospective cohort of US adults. American Journal of Clinical Nutrition. 95(2):454-464.
- Dwyer, J., Nahin, R.L., Barnes, P.M., Jacques, P.F., Sempos, C.T., Bailey, R., Rogers, G.T. 2013. Prevalence and predictors of children's dietary supplement use: the 2007 National Health Interview Survey. American Journal of Clinical Nutrition. 97(6):1331-1337.
- Jacques, P.F., Cassidy, A., Rogers, G., Peterson, J.J., Meigs, J.B., Dwyer, J.T. 2013. Higher dietary flavonol intake is associated with lower incidence of Type 2 Diabetes. Journal of Nutrition. 143(9):1474-1480.
- Jessri, M., Rashidkhani, B., Hajizadeh, B., Jacques, P.F. 2012. Adherence to Mediterranean-style dietary pattern and risk of esophageal squamous cell carcinoma: a case-control study in Iran. Journal of the American College of Nutrition. 31(5):338-351. DOI: 10.1080/07315724.2012.10720437.
- Holt, M.D., Moreau, R.A., Dermarderosian, A., Mckeown, N., Jacques, P.F. 2012. Accelerated solvent extraction of alkylresorcinols in food products containing uncooked and cooked wheat. Journal of Agricultural and Food Chemistry. 60(19):4799-4802.
- Chaganti, R., Tolstykh, I., Javaid, M.K., Neogi, T., Torner, J., Curtis, J. , Jacques, P., Felson, D., Lane, N.E., Nevitt, M.C. 2013. High plasma levels of vitamin C and E are associated with incident radiographic knee osteoarthritis. Osteoarthritis and Cartilage. 22(2):190-196.
- Williams, S.R., Yan, Q., Chen, F., Liu, X., Keene, K.L., Jacques, P.F., Chen, W., Weinstein, G., Hsu, F., Beiser, A., Wang, L., Bookman, E., Doheny, K.F., Wolf, P.A., Zilka, M., Selhub, J., Nelson, S., Gogarten, S.M. , Worrall, B.B., Seshadri, S., Sale, M.M. 2014. Genome-wide meta-analysis of homocysteine and methionine metabolism identifies five one carbon metabolism loci and a novel association of ALDH1L1 with ischemic stroke. PLoS Genetics. 10(3):e1004214.
- Nettleton, J.A., Hivert, M., Lemaitre, R.N., Mckeown, N.M., Mozaffarian, D. , Tanaka, T., Wojczynski, M.K., Hruby, A., Djousse, L., Ngwa, J.S., Follis, J., Dimitrious, M., Ganna, A., Houston, D.K., Kanoni, S., Mikkila, V., Manichaikul, A., Ntalla, I., Renstrom, F., Sonestedt, E., Van Rooji, F.J., Bandinelli, S., De Koning, L., Ericson, U., Hassanali, N., Kiefte-De Jong, J.C., Lohman, K.K., Raitakari, O., Popoutsakis, C., Sjogren, P., Stirrups, K., Ax, E., Deloukas, P., Groves, C.J., Jacques, P.F., Johansson, I., Liu, Y., Mccarthy, M.I., North, K., Viikari, J., Zillikens, M., Dupuis, J., Hofman, A., Kolovou, G., Mukamal, K., Prokopenko, I., Rolandsson, O., Seppala, L., Cupples, L., Hu, F., Kahonen, M., Uitterlinden, A.G., Borecki, I.B., Fernucci, L., Jacobs, D.R., Kritchevsky, S.B., Orho-Melander, M., Pankow, J.S., Lehtimaki, T., Witteman, J., Ingelsson, E., Siscovick, D.S., Dedoussis, G., Meigs, J.B., Franks, P.W. 2012. Meta-analysis investigating associations between healthy diet and fasting glucose and insulin levels and modification by loci associated with glucose homeostasis in data from 15 cohorts. American Journal of Epidemiology. 177(2):103-115.
- Van Meurs, J., Pare, G., Schwartz, S.M., Hazra, A., Tanaka, T., Vermuelen, S.H., Cotlarciuc, I., Yuan, X., Malarstig, A., Bandinelli, S., Bis, J.C., Blom, H., Brown, M.J., Chen, C., Chen, Y., Clarke, R.J., Deghan, A., Erdman, J., Ferrucci, L., Hamsten, A., Hofman, A., Hunter, D.J., Goel, A., Johnson, A.D., Kathiresan, S., Kampman, E., Kiel, D.P., Kiemeney, L., Chambers, J.C., Kraft, P., Lindemans, J., Mcknigh, B., Nelson, C.P., O'Donnell, C.J., Psaty, B.M., Ridker, P.M., Rivadeneira, F., Rose, L.M., Seedorf, U., Siscovick, D.S., Schunkert, H., Selhub, J., Ueland, P.M., Vollenweider, P., Waever, G., Waterworth, D., Watkins, H., Witteman, J., Den Heijer, M., Jacques, P., Uitterlinden, A.G., Kooner, J.S., Rader, D.J., Reilly, M.P., Mooser, V., Chasman, D.I., Samani, N.J., Ahmandi, K. 2013. Common genetic loci influencing plasma homocysteine concentrations and their effect on risk of coronary artery disease. American Journal of Clinical Nutrition. 98(3):668-676.
- Hruby, A., Meigs, J.B., O'Donnell, C.J., Jacques, P.F., Mckeown, N.M., Hoffmann, U. 2013. Magnesium intake is inversely associated with coronary artery calcification: the Framingham Heart Study. Journal of the American College of Cardiology. 7(1):59-69.
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Progress 10/01/12 to 09/30/13
Outputs
Progress Report Objectives (from AD-416): 1. Using an epidemiologic approach, investigate the role of whole grains, selected nutrients, other bioactive food components, and healthy dietary patterns in preventing the development of age-related conditions such as type 2 diabetes mellitus, cardiovascular disease, cancer, musculoskeletal disorders and age-related eye disease. 2. Determine the validity of biomarkers for whole grain intake, their use in assessing relationships between whole grain intake and disease risk, and the relationship between these biomarkers and insulin resistance phenotypes. 3. Using an epidemiologic approach, examine determinants of adherence to the recommended dietary patterns in the Dietary Guidelines for Americans (DGA) and the relation between adherence to these patterns and prevention of age-related weight gain, abdominal obesity, and related metabolic disorders such as inflammation, endothelial dysfunction and insulin resistance. 4. Using an epidemiologic approach, investigate safe upper limits for the dietary intake of folic acid. 5. Using an epidemiologic approach, determine relationships between dietary intake and nutrient status and the prevention of age-related cognitive decline in humans. 6. Using an epidemiologic approach, investigate the role of nutritional factors in limiting the cormorbidities such as CVD and premature mortality in individuals with chronic kidney disease (CKD). Approach (from AD-416): Many age-related conditions, such as cardiovascular disease, diabetes, dementia, cancer, musculoskeletal disorders and age-related eye disease, appear to have strong nutritional components. Improved nutrition through public health recommendations and interventions could have a tremendous impact on the economic and societal costs associated with these disabilities, but development of recommendations and interventions requires a greater understanding of the presumptive role that nutrition plays in delaying the onset of disease and disability. Epidemiologic methods applied to community-based investigations of aging populations provide a valuable tool to help meet this need. We will use these methods to address project objectives. Our research on nutrition and risk of obesity and chronic disease (Objective 1) included projects related to weight, cardiovascular disease, diabetes, and age-related cognitive and musculoskeletal changes. As part of our research on the relation between diet and weight, we demonstrated that individuals who consumed greater than or equal to 3 servings/day of total dairy had smaller gains in weight than those consuming <1 serving/day and individuals who consumed less than or equal to 3 servings/week of yogurt had smaller gains in weight and waist circumference than those consuming <1 serving/week over 13 years of follow-up. Preliminary findings from two other studies showed that greater whole grain consumption was associated with a smaller annualized gain in waist circumference (abdominal fat) over 14 years of follow-up and sugar-sweetened beverage consumption is associated with greater accumulations over time of abdominal visceral fat tissue, an important risk factor for cardiovascular and other metabolic diseases. As part of our research on the relation between diet and cardiovascular disease, we observed that five flavonoid classes � anthocyanidins, flavan-3-ols, flavones, flavonols, and proanthocyanidins � were each individually associated with lower risk of fatal cardiovascular disease over 7 years of follow-up in 38,180 men and 60,289 women from the Cancer Prevention Study II Nutrition Cohort. We also had preliminary findings from three studies relating nutrition and cardiovascular disease risk showing that higher yogurt consumption was associated with low incidence of hypertension, that higher magnesium intake is associated with less coronary artery calcification (a relatively novel and strong determinant of cardiovascular disease), and that the inverse relationship between statin use and cholesterol was enhanced among those consuming greater amounts of whole grains. As part of our research on the relation between diet and diabetes/metabolic risk, we demonstrated that each 2.5-fold increase in long-term flavonol and flavan-3-ol intakes were associated, respectively, with a 26% and 11% lower incidence of type 2 diabetes over a 12 year follow-up period. We also examined how diet might affect the relation between genetic markers and metabolic risk in two large meta- analyses. In one study we demonstrated that the relation between a healthy diet pattern and fasting glucose and insulin levels was modified by loci associated with glucose homeostasis and in a second meta-analysis higher magnesium intake was associated with lower fasting glucose and insulin, with no evidence of interaction with select genetic loci. As part of our research on age-related cognitive changes, we have preliminary findings suggesting that folate status well above the replete range may worsen the effect of low vitamin B-12 status on memory and generally hasten cognitive decline. As part of our research on age- related musculoskeletal change, we demonstrated that high-protein intake was associated with a modest increase in the appendicular skeletal muscle mass index in non-obese, physically inactive subjects. Our progress on characterizing the role of nutrition in risk of age-related disease is crucial in identifying potential interventions aimed at maintaining health as we age. As part of our work of identifying biomarkers for whole grain consumption (Objective 2), we conducted a whole wheat feeding trial and as part of the preliminary analyses from that trial we observed a dose-response relationship between whole wheat intake and baseline urinary alkylresorcinol metabolites, suggesting that urinary alkylresorcinol metabolites may be useful biomarkers of whole wheat intake. We also demonstrated that higher circulating alkylresorcinol levels were related to lower BMI in older adults. The availability of biomarkers, like alkylresorcinols, will ultimately help us to better characterize consumption of whole grains by Americans, and consequently, help us to better understand the benefits of whole grains on healthy aging. As part of the whole wheat feeding trial, we also conducted a pilot study to see if whole wheat consumption, which is rich in prebiotics (dietary fibers that are believed to enhance the growth of beneficial gut bacteria) can modify the types and proportions of gut bacteria. We are currently analyzing these data. There is growing evidence that the types of gut bacteria may influence aspects of health from inflammatory bowel disease to weight gain (Objective 1). As part of our work of examining the benefits of adherence to the Dietary Guidelines for Americans and other health eating patterns (Objective 3), we demonstrated that that yogurt consumers had a better overall diet quality than non-consumers, and even after adjustment for overall diet quality, yogurt consumers, compared to non-consumers, were substantially less likely to have low or inadequate intakes of potassium, vitamins B2 and B12, calcium, magnesium, and zinc. We also revised our Dietary Guidelines for Americans Adherence Index (DGAI) to conform to the 2010 DGA recommendations and used it to demonstrate in preliminary analyses that Americans� diets are more consistent with the DGA recommendations now than there were 10 to 15 years in the past. In a second preliminary analyses we correlated an inflammation score based on the sum of 11 ranked inflammatory biomarkers and the DGAI score to demonstrate that individual who had the highest adherence to the DGA recommendation had about a 9% lower inflammation score than individuals with the lowest adherence to the recommendations suggesting that greater adherence to the 2010 DGA may decrease chronic disease prevalence due to reduced risk of inflammation. As part of our work of examining the safety of high folic acid intakes, we demonstrated that cognitive decline was significantly faster in persons with low plasma vitamin B-12 levels and having a high plasma folate concentration associated with folic acid intake or using folic acid supplements enhanced this decline in cognitive function. In preliminary analyses we demonstrated that high folate status above the replete range predicted decline in a variety of cognitive domains including verbal and visual recall and executive function. The association with visual recall was enhanced among individuals with low vitamin B12 status. Our work in this area of research will help us identify the upper safe levels of folic acid intake. As part of our research on B vitamins and cognitive function (Objective 5), we are completing analyses and drafting manuscripts that explore the potential effects of B vitamin supplements on age-related cognitive changes using data from a randomized trial of B vitamin supplementation and cognitive function. Our accomplishments related to this objective will help us understand the role of nutrition in preventing age-related cognitive decline. Accomplishments 01 Dairy consumption slows age-related gains in weight and waist circumference. The possibility that consuming dairy products may influence body weight has been considered in a number of randomized controlled trials (RCTs) and prospective observational studies. Collectively they have not fully accounted for weight maintenance or prevention of weight gain, or have largely failed to account for the changes in dairy intake during follow-up, the higher overall diet quality of dairy consumers, and possible differential effects of dairy food type (e.g., high vs. low fat, fermented vs. not fermented). To overcome deficiencies of earlier studies, ARS funded researchers at JMUSDA-HNRCA at Tufts University at Boston, Massachusetts used data from a cohort with several repeated measurements on dietary intake, overall diet quality, body weight and waist circumference (WC) to examine the association between consumption of different types of dairy products and long-term changes in weight and WC among American adults over an average follow-up period of 13-years. Participants who consumed 3 or more servings per day of total dairy had 50% smaller rate of weight gain per year than those consuming <1 serving per day. Participants who consumed 3 or more servings per week of yogurt also gained 50% less weight and 20% less waist circumference per year than those consuming <1 serving per week. Skim/low-fat milk, cheese, total high-fat or total low-fat dairy intake were not associated with long- term change in weight or WC. These results provide evidence for the need to include specific dietary guidance for food product categories in the fight against obesity. 02 High folic acid increases cognitive decline in vitamin B12 deficient individuals. Questions remain about the safety of high folic acid intakes. Accumulating evidence suggests that high folic acid intake interacts with vitamin B12 deficiency in a manner that masks the most common symptoms of vitamin B12 deficiency while precipitating the development of neuropathy associated with B12 deficiency. This may be a special concern among older adults in whom vitamin B-12 deficiency is highly prevalent due to the diminished ability to detach vitamin B-12 from food protein because of age-related achlorhydria. ARS funded researchers at JMUSDA-HNRCA at Tufts University at Boston, Massachusetts demonstrated that cognitive decline was significantly faster in persons with low plasma vitamin B-12 levels and that having a high plasma folate concentration associated with folic acid intake or using folic acid supplements enhanced this decline in cognitive function. Results of this study will help inform recommendations for vitamin B12 and folic acid intakes, particularly for safe upper limits for folic acid intake. 03 Higher flavonol intakes as associated with a lower type 2 diabetes incidence. There is growing evidence based on in vitro and animal research that flavonoids, a class of polyphenols, can improve glucose homeostasis, and enhance insulin secretion and sensitivity. There are relatively few clinical studies that examined the effect of flavonoid interventions in humans on glucose homeostasis and insulin resistance, but a recent systematic review of cocoa trials (cocoa being a good source of the flavonoid flavan-3-ol) showed that cocoa interventions improved insulin resistance. These findings would suggest that flavonoids might reduce the risk of developing type 2 diabetes (T2D). The purpose of the present study was to examine the hypothesis that higher intakes of three flavonoid classes previously shown to relate to glucose homeostasis and insulin resistance, specifically the flavonols, flavan-3-ols and anthocyanins, are associated with a lower incidence of T2D. ARS funded researchers at JMUSDA-HNRCA at Tufts University at Boston, Massachusetts observed that a 2.5-fold increase in flavonol and flavan-3-ol intakes were associated with a 26% and 11% lower incidence of T2D, respectively. Our observations support previous experimental evidence of a possible beneficial relationship between increased flavonol intake and risk of T2D, a largely preventable condition with serious health consequences, including a greater risk of heart disease, stroke, peripheral neuropathy, renal disease, and vision loss.
Impacts
(N/A)
Publications
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Progress 10/01/09 to 09/30/10
Outputs
Progress Report Objectives (from AD-416) 1. Using an epidemiologic approach, investigate the role of whole grains, selected nutrients, other bioactive food components, and healthy dietary patterns in preventing age-related development of metabolic risk factors for type 2 diabetes mellitus, cardiovascular disease, cancer and musculoskeletal disorders. 2. Determine the validity of biomarkers for whole grain intake, their use in assessing relationships between whole grains intake and disease risk, and the relationship between these biomarkers and insulin resistance phenotypes. 3. Using an epidemiologic approach, examine determinants of adherence to the recommended dietary patterns in the Dietary Guidelines for Americans (DGA) and the relation between adherence to these patterns and prevention of age-related weight gain, abdominal obesity, and related metabolic disorders such as inflammation, endothelial dysfunction and insulin resistance. 4. Using an epidemiologic approach, investigate safe upper limits for the dietary intake of folic acid. 5. Using an epidemiologic approach, determine relationships between B- vitamin status, homocysteine levels, genetic mutations and the prevention of age-related cognitive decline in humans. 6. Using an epidemiologic approach, examine the relationships between vitamin D and fatty acid intakes and age-related eye diseases, including cataract and maculopathy. Approach (from AD-416) Many age-related conditions, such as cardiovascular disease, diabetes, dementia, cancer, musculoskeletal disorders and age-related eye disease, appear to have strong nutritional components. Improved nutrition through public health recommendations and interventions could have a tremendous impact on the economic and societal costs associated with these disabilities, but development of recommendations and interventions requires a greater understanding of the presumptive role that nutrition plays in delaying the onset of disease and disability. Epidemiologic methods applied to community-based investigations of aging populations provide a valuable tool to help meet this need. We will use these methods to address project objectives. Our research on nutrition and risk of obesity and chronic disease (Objective 1) included projects related to obesity, insulin resistance, metabolic syndrome, diabetes, and cardiovascular disease. As part of our research on weight gain and obesity, we showed that whole-grain and cereal fiber intakes were inversely related to percent total body and trunk fat mass and that better adherence to a Mediterranean diet was associated with a lower incidence of abdominal obesity. As part of our research on diet and metabolic risk, we observed that higher vitamin D status was associated with a lower risk of insulin resistance and diabetes and better adherence to a Mediterranean diet was associated with a lower incidence of metabolic syndrome and insulin resistance. As part of our research on diet and cardiovascular disease, we showed that a high glycemic index diet unfavorably affects triglycerides and HDL cholesterol, and that vitamin B6 status was inversely related to inflammation, an important cardiovascular disease risk factor. We completed the update of our food frequency flavonoid database for our project on flavonoid intake and cardiovascular disease risk and completed most of the statistical analyses for our project on plant-based diets, diet quality and cardiovascular disease risk. As part of our work of identifying biomarkers whole grain consumption (Objective 2), we measured blood alkylresorcinol levels. Alkylresorcinols are unique chemicals found in whole wheat and rye and are believed to be a potentially useful objective and quantitative marker of whole wheat consumption. These biomarkers will ultimately help determine consumption of whole grains by Americans. As part of our research on the Dietary Guidelines for Americans (DGA) (Objective 3), we showed that that better adherence to 2005 DGA is associated with a reduced progression of coronary artery atherosclerosis in women. This demonstrates that adherence the 2005 DGA is associated with a reduce risk of disease progression. As part of our research on safe upper limits of folic acid (Objective 4), we showed that unmetabolized folic acid, the synthetic form of the vitamin folate found in vitamin supplements and fortified foods, was detected in 50% of older Americans with folic acid intakes above 585 micrograms/day. We also showed that among older Americans with inadequate vitamin B12 status, the presence of circulating unmetabolized folic acid was related to lower scores on cognitive tests. This accomplishment helps us to better understand the basis for folic acid recommendations. As part of our research on B vitamins and cognitive function (Objective 5), we have completed recruitment and initiated baseline laboratory analyses. This accomplishment will help us understand the role of nutrition in age- related cognitive decline. For publications related to this project, see parent project #1950-51530- 009-00D. Accomplishments 01 Whole-Grain Intake and Cereal Fiber Are Associated with Lower Abdominal Adiposity. Foods high in dietary fiber may play an important role in regulating body weight. Few observational studies have examined the relationship between dietary fiber from different sources and body fat. ARS-funded researchers from Tufts University in Boston, MA examined the relation between grain intake (whole and refined), and measures of body fat. They observed that higher whole-grain and cereal fiber intakes were associated with a lower body mass index (a higher body mass index is a marker of overweight), percent total body fat, and percent trunk fat mas (trunk fat is a surrogate measure for abdominal fat mass, which is more strongly associated with risk of metabolic disorders than other fat depo . This research suggests that higher intakes of cereal fiber, particular from whole-grain sources, may be one means of limiting body fat mass, particularly in the abdominal region. 02 Plasma 25-Hydroxyvitamin D Is Associated with Insulin Resistance in Nondiabetic Adults. Insulin resistance is the main defect that characterizes the development of type 2 diabetes, but there is little information on the relationship between vitamin D status and insulin resistance. To advance our understanding of the role of vitamin D statu in the development of insulin resistance, ARS-funded researchers from Tufts University in Boston, MA examined the association between insulin resistance and plasma vitamin D levels. They observed that individuals with higher plasma vitamin D concentrations had less insulin resistance. These results suggest that maintaining optimal vitamin D status might be important for the prevention of type 2 diabetes. 03 Mediterranean-Style Dietary Pattern is Associated with a Reduced Risk of Metabolic Syndrome Traits and Incidence. There is evidence of the benef of the Mediterranean-style dietary pattern on disease risk in Mediterranean countries, but the health benefits of consuming a Mediterranean-style dietary pattern based on foods available in the American diet has not been demonstrated. Therefore, ARS-funded researche from Tufts University in Boston, MA examined the relation between consumption of a Mediterranean-style dietary pattern and insulin resistance, metabolic syndrome and its component risk factors (larger waist circumference, elevated blood glucose and triglyceride levels, and hypertension, and low HDL-cholesterol) in a population-based sample of adult Americans. They observed that individuals whose diets had greater conformity to the Mediterranean-style dietary pattern had smaller increases in waist circumference, blood glucose and triglyceride levels, and greater increases in HDL-cholesterol; were less likely to develop insulin resistance; and had a lower incidence of metabolic syndrome. These findings suggest that consumption of a diet consistent with the principles of the Mediterranean-style diet may be protective against developing metabolic syndrome, a potent risk factor for both diabetes an cardiovascular disease risk, in an American population.
Impacts
(N/A)
Publications
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