Archive

Research Nut: Brazil Nuts

Does nut consumption reduce mortality and/or risk of cardiometabolic disease? An updated review based on meta-analyses.

Kim, Y., J.B. Keogh, P.M. Clifton, 2019. Does nut consumption reduce mortality and/or risk of cardiometabolic disease? An updated review based on meta-analyses. Int. J. Environ. Res. Public Health. 16, 4957; doi:10.3390/ijerph16244957.

Aim. We aimed to determine if nut consumption decreases mortality and/or the risk of cardiometabolic diseases based on updated meta-analyses of epidemiological and intervention studies. Methods. An updated electronic search was conducted in PubMed/MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and the Cochrane Library databases for original meta-analyses to investigate the effects of nut consumption on cardiometabolic disease in humans. Results. Seven new meta-analyses were included in this updated review. Findings similar to our previous review were observed, showing that nut consumption significantly decreased cardiovascular disease (CVD) mortality (-19% to -25%; n = 4), coronary heart disease (CHD) mortality (-24% to -30%; n = 3), stroke mortality (-17% to -18%; n = 3), CVD incidence (-15% to -19 %; n = 4), CHD [or coronary artery disease (CAD)] incidence (-17% to -34%; n = 8), and stroke incidence (-10% to -11%; n = 6) comparing high with low categories of nut consumption. Fasting glucose levels (0.08 to 0.15 mmol/L; n = 6), total cholesterol (TC; 0.021 to 0.30 mmol/L; n = 10), and low-density lipoprotein cholesterol (LDL-C; 0.017 to 0.26 mmol/L; n = 10) were significantly decreased with nut consumption compared with control diets. Body weight and blood pressure were not significantly affected by nut consumption. Conclusion. Nut consumption appears to exert a protective effect on cardiometabolic disease, possibly through improved concentrations of fasting glucose, total cholesterol, and LDL-C.

Food groups in dietary prevention of Type 2 diabetes.

Basiak-Rasała, A., D. Różańska, K. Zatońska, 2019. Food groups in dietary prevention of Type 2 diabetes. Rocz Panstw Zakl Hig 70(4):347-357.

According to the World Health Organization diabetes will be the seventh leading cause of death worldwide in 2030. Majority of diabetic patients suffer from type 2 diabetes (T2DM), which is mostly avoidable. The most important modifiable risk factors of type 2 diabetes are: overweight and obesity, improper diet, sedentary lifestyle and tobacco smoking. Even in prediabetic state, improving diet and physical activity can slow down or even stop progression to diabetes. In the view of health burden of diabetes it is essential to thoroughly investigate the risk factors and develop more specific preventive strategies. Recently published studies focus on food groups rather than individual products to assess the link between nutrition and risk of type 2 diabetes. Identifying food groups of possible beneficial and deleterious effect on the risk of type 2 diabetes could facilitate the dietary counselling. The aim of the overview is to summarize the possible association between consumption of food groups on the risk of type 2 diabetes on the basis of available literature. Observations from studies and meta-analyses indicate on an inverse association between consumption of fresh vegetables and fruit, whole grains, lean dairy, fish, nuts and the risk of type 2 diabetes. Food groups that seemed to increase the risk of type 2 diabetes are: red and processed meat, refined grains, sugar-sweetened beverages. It is important to note, that no individual nutrients, but diverse dietary pattern, composed of every recommended food group in adequate amounts can contribute to healthy lifestyle and T2DM prevention.

The Alternative Healthy Eating Index and physical function impairment in men.

Hagan, K.A., F. Grodstein, 2019. The Alternative Healthy Eating Index and physical function impairment in men. J Nutr Health Aging. 23(5):459-465.

Objectives: Physical function is increasingly recognized as integral to healthy aging, in particular as a core component of mobility and independent living in older adults. Thus, it is important to identify strategies for the prevention of physical function decline. Design: Longitudinal cohort study. Setting and Participants: A total of 12,658 men from the Health Professionals Follow-Up Study were followed from 2008–2012. Measurements: We examined the association between the Alternative Healthy Eating Index-2010 (AHEI), a measure of diet quality combining 11 dietary components (vegetables, fruits, nuts and legumes, red and processed meats, sugar-sweetened beverages and fruit juices, alcohol, whole grains, omega-3 fatty acids, polyunsaturated fatty acids, trans fatty acids, sodium), and impairment in physical function, as measured by the SF-36. Multivariable logistic regression models were used to estimate the odds ratios (OR) and 95% confidence intervals (CI) of impairment in physical function. Results: In the multivariable-adjusted model, each 10-point increase in total AHEI score was associated with a 10% lower odds of impairment in physical function (OR=0.90, 95% CI: 0.86,0.95), and in the categorical analysis, men with AHEI scores in the top quintile had a 26% lower odds (OR=0.74, 95% CI:0.63,0.86) compared with men in the bottom quintile. For individual AHEI components, higher intake of vegetables (p-trend=0.01), nuts and legumes (p-trend<0.01), polyunsaturated fatty acids (p-trend<0.01) and lower intake of red and processed meats (p-trend=0.03) and sugar-sweetened beverages (p-trend=0.01) were significantly associated with lower odds of physical impairment. For specific foods, higher consumption of lettuce, broccoli, blueberries, peanuts, walnuts and other nuts were associated with lower odds of impairment. Conclusions: In this large cohort of older men, better overall diet quality was significantly associated with a lower odds of impairment in physical function. Given the value of physical function to healthy aging and quality of life, this may represent a particularly compelling public health rationale for older men to improve their diet.

Consumption of Brazil nuts with high selenium levels increased inflammation biomarkers in obese women: A randomized controlled trial.

G.B.S. Duarte, B.Z. Reis, M.M. Rogero, E. Vargas-Mendez, F.B. Júnior, C. Cercato, S.M.F. Cozzolino, 2019. Consumption of Brazil nuts with high selenium levels increased inflammation biomarkers in obese women: A randomized controlled trial. Nutrition. 63-64:162-168.

Objective: Increased inflammatory response is an important factor in the pathophysiology of obesity. The mineral selenium (Se), of which one of the main food sources is the Brazil nut, has important antioxidant and anti-inflammatory functions through the action of selenoproteins. Thus, the evaluation of the influence of this micronutrient in this context is of great relevance. The aim of this study was to evaluate the effects of Brazil nut intake with high Se concentrations on inflammatory biomarkers and its relation to Se status in obese women. Methods:A randomized controlled clinical trial was carried out with 55 women recruited at Clinical Hospital in São Paulo, Brazil. Patients were randomly assigned to either the Brazil nut group (BN) or the control group (CO) and followed up for 2 mo. The BN group consumed 1 unit/d of Brazil nuts (∼ 1261 μg/Se); the CO group did not receive any intervention. At baseline and after 2 mo, analysis of biochemical parameters related to Se status, oxidative stress, and inflammatory biomarkers were performed. Results:At baseline, both groups did not present Se deficiency. In the BN group, a significant increase (P < 0.05) in all Se biomarkers and in gene expression of several proinflammatory parameters (interleukin-6, tumor necrosis factor-α, and Toll-like receptors 2 and 4) were observed after the intervention period. No changes were observed for the CO group. Conclusion:Although there were no changes in plasma inflammatory biomarkers levels, a significant increase in gene expression may be an indication of a proinflammatory stimulus in obesity, induced by the consumption of Brazil nuts with high Se levels.

Nut consumption in relation to cardiovascular disease incidence and mortality among patients with diabetes mellitus.

Liu, G., M. Guasch-Ferre, Y. Hu, Y. Li, F.B. Hu, E.B. Rimm, J.E. Manson, K. Rexrode, Q. Sun, 2019. Nut consumption in relation to cardiovascular disease incidence and mortality among patients with diabetes mellitus. Circulation Research. doi.org/10.1161/CIRCRESAHA.118.314316

Rationale: The evidence regarding the potential health benefits of nut consumption among individuals with type 2 diabetes is limited. Objective: To examine intake of total and specific types of nuts, including tree nuts and peanuts, in relation to subsequent risk of cardiovascular disease (CVD), including coronary heart disease (CHD) and stroke, and all-cause and cause-specific mortality among individuals with diabetes. Methods and Results: This prospective analysis included 16,217 men and women with diabetes at baseline or diagnosed during follow-up (Nurses’ Health Study: 1980-2014, Health Professionals Follow-Up Study: 1986-2014). Nut consumption was assessed using a validated food frequency questionnaire and updated every 2-4 years. During 223,682 and 254,923 person-years of follow-up, there were 3,336 incident CVD cases and 5,682 deaths. Higher total nut consumption was associated with a lower risk of CVD incidence and mortality. The multivariate-adjusted hazard ratios (95% confidence intervals) for participants who consumed 5 or more servings of total nuts per week (1 serving=28g), compared with those who consumed less than 1 serving per month, were 0.83 (0.71-0.98; P trend=0.01) for total CVD incidence, 0.80 (0.67-0.96; P trend=0.005) for CHD incidence, 0.66 (0.52-0.84; P trend<0.001) for CVD mortality, and 0.69 (0.61-0.77; P trend<0.001) for all-cause mortality. Total nut consumption was not significantly associated with risk of stroke incidence or cancer mortality. For specific types of nuts, higher tree nut consumption was associated with lower risk of total CVD, CHD incidence, and mortality due to CVD, cancer, and all causes, while peanut consumption was associated with lower all-cause mortality only (all P trend<0.001). In addition, compared with participants who did not change the consumption of total nuts from pre- to post-diabetes diagnosis, participants who increased consumption of total nuts after diabetes diagnosis had an 11% lower risk of CVD, a 15% lower CHD risk, a 25% lower CVD mortality, and a 27% lower all-cause mortality. The associations persisted in subgroup analyses stratified by sex/cohort, body mass index at diabetes diagnosis, smoking status, diabetes duration, nut consumption before diabetes diagnosis, or diet quality. Conclusions: Higher consumption of nuts, especially tree nuts, is associated with lower CVD incidence and mortality among participants with diabetes. These data provide novel evidence that supports the recommendation of incorporating nuts into healthy dietary patterns for the prevention of CVD complications and premature deaths among individuals with diabetes.

The effect of nuts on markers of glycemic control: a systematic review and meta-analysis of randomized controlled trials.

Tindall, A.M., E.A. Johnston, P.M. Kris-Etherton, K.S. Petersen, 2019. The effect of nuts on markers of glycemic control: a systematic review and meta-analysis of randomized controlled trials. Am J Clin Nutr. 109:297–314.

Background: Observational evidence suggests higher nut consumption is associated with better glycemic control; however, it is unclear if this association is causal. Objectives: We aimed to conduct a systematic review and meta-analysis of randomized controlled trials to examine the effect of tree nuts and peanuts on markers of glycemic control in adults. Methods: A systematic review and meta-analysis of randomized controlled trials was conducted. A total of 1063 potentially eligible articles were screened in duplicate. From these articles, 40 were eligible for inclusion and data from these articles were extracted in duplicate. The weighted mean difference (WMD) between the nut intervention and control arms was determined for fasting glucose, fasting insulin, glycated hemoglobin (HbA1c), and homeostasis model assessment of insulin resistance (HOMA-IR) using the DerSimonian and Laird random-effects method. For outcomes where a limited number of studies were published, a qualitative synthesis was presented. Results: A total of 40 randomized controlled trials including 2832 unique participants, with a median duration of 3 mo (range: 1–12 mo), were included. Overall consumption of tree nuts or peanuts had a favorable effect on HOMA-IR (WMD: −0.23; 95% CI: −0.40, −0.06; I2=51.7%) and fasting insulin (WMD: −0.40μIU/mL;95% CI: −0.73, −0.07μ IU/mL; I2 = 49.4%). There was no significant effect of nut consumption on fasting blood glucose (WMD: −0.52 mg/dL;95% CI: −1.43,0.38mg/dL; I2 =53.4%) o rHbA1c (WMD: 0.02%; 95% CI: −0.01%, 0.04%; I2 =51.0%). Conclusions: Consumption of peanuts or tree nuts significantly decreased HOMA-IR and fasting insulin; there was no effect of nut consumption on HbA1c or fasting glucose. The results suggest that nut consumption may improve insulin sensitivity. In the future, well-designed clinical trials are required to elucidate the mechanisms that account for these observed effects.

Nut and peanut butter consumption and the risk of lung cancer and its subtypes: A prospective cohort study.

Nieuwenhuis, I., P.A. van den Brandt, 2019. Nut and peanut butter consumption and the risk of lung cancer and its subtypes: A prospective cohort study. Lung Cancer. 128:57-66.
Objectives: Nut consumption has been associated with reduced cancer-related mortality, but evidence for a relation between nut intake and lung cancer risk is limited. We investigated the association between total nut, tree nut, peanut, and peanut butter intake and the risk of lung cancer and its subtypes in the Netherlands Cohort Study. Materials and Methods: In 1986, dietary and lifestyle habits of 120,852 participants, aged 55–69 years, were measured with a questionnaire. After 20.3 years of follow-up, 3720 subcohort members and 2861 lung cancer cases were included in multivariable case-cohort analyses. Results: Total nut intake was not significantly associated with total lung cancer risk in men or women. For small cell carcinoma, a significant inverse association with total nut intake was observed in men after controlling for detailed smoking habits (HR (95%CI) for 10+ g/day vs. non-consumers: 0.62 (0.43-0.89), p-trend: 0.024). Inverse relations with small cell carcinoma were also found for tree nut and peanut intake in men in continuous analyses (HR (95%CI) per 5g/day increment: 0.70 (0.53-0.93) and 0.93 (0.88-0.98), respectively). For the other lung cancer subtypes, no significant associations were seen in men. Nut intake was not related to the risk of lung cancer subtypes in women, and no associations were found for peanut butter in both sexes. Conclusion: Increased nut intake might contribute to the prevention of small cell carcinoma in men. No significant associations were found in men for the other subtypes or total lung cancer, in women, or for peanut butter intake.

Nut Consumption and Survival in Patients With Stage III Colon Cancer: Results From CALGB 89803 (Alliance).

Fadelu, T., S. Zhang, D. Niedzwiecki, X. Ye, L.B. Saltz, R.J. Mayer, R.B. Mowat, R. Whittom, A. Hantel, A.B. Benson, D.M. Atienza, M. Messino, H.L. Kindler, A. Venook, S. Ogino, K. Ng, K. Wu, W. Willett, E. Giovannucci, J. Meyerhardt, Y. Bao, C.S. Fuchs, 2018. Nut Consumption and Survival in Patients With Stage III Colon Cancer: Results From CALGB 89803 (Alliance). J Clin Oncol. 36(11):1112-1120.

Purpose: Observational studies have reported increased colon cancer recurrence and mortality in patients with states of hyperinsulinemia, including type 2 diabetes, obesity, sedentary lifestyle, and high glycemic load diet. Nut intake has been associated with a lower risk of type 2 diabetes, metabolic syndrome, and insulin resistance. However, the effect of nut intake on colon cancer recurrence and survival is not known. Patients and Methods: We conducted a prospective, observational study of 826 eligible patients with stage III colon cancer who reported dietary intake on food frequency questionnaires while enrolled onto a randomized adjuvant chemotherapy trial. Using Cox proportional hazards regression, we assessed associations of nut intake with cancer recurrence and mortality. Results: After a median follow-up of 6.5 years, compared with patients who abstained from nuts, individuals who consumed two or more servings of nuts per week experienced an adjusted hazard ratio (HR) for disease-free survival of 0.58 (95% CI, 0.37 to 0.92; Ptrend = .03) and an HR for overall survival of 0.43 (95% CI, 0.25 to 0.74; Ptrend = .01). In subgroup analysis, the apparent benefit was confined to tree nut intake (HR for disease-free survival, 0.54; 95% CI, 0.34 to 0.85; Ptrend = .04; and HR for overall survival, 0.47; 95% CI, 0.27 to 0.82; Ptrend = .04). The association of total nut intake with improved outcomes was maintained across other known or suspected risk factors for cancer recurrence and mortality. Conclusion: Diets with a higher consumption of nuts may be associated with a significantly reduced incidence of cancer recurrence and death in patients with stage III colon cancer.

Effect of nut consumption on semen quality and functionality in healthy men consuming a Western-style diet: a randomized controlled trial.

Salas-Huetos, A., R. Moraleda, S. Giardina, E. Anton, J. Blanco, J. Salas-Salvadó, M. Bulló, 2018. Effect of nut consumption on semen quality and functionality in healthy men consuming a Western-style diet: a randomized controlled trial. Am J Clin Nutr. 108:953–962.

Background: Human semen quality has declined in industrialized countries. Pollution, smoking, and the consumption of a Western style diet are all hypothesized as potential causes. Objective: We evaluated the effect of chronic consumption of nuts on changes in conventional semen parameters and the potential mechanisms implicated. Design: The FERTINUTS study was a 14-wk randomized, controlled, parallel trial. A total of 119 healthy men, aged 18–35 y, were allocated to 1 of 2 intervention groups: one group was fed the usual Western-style diet enriched with 60 g of a mixture of nuts/d (nut group), and the other was fed the usual Western-style diet avoiding nuts (control group). Semen and blood samples were collected at baseline and at the end of the intervention. Dietary information was recorded throughout the trial. Changes in conventional semen parameters (pH, volume, sperm count and concentration, motility, and morphology) were determined as primary outcomes. The effect of nut consumption on sperm DNA fragmentation (SDF), reactive oxygen species (ROS) production, chromosome anomalies (X, Y, and 18), total DNA methylation, and microRNA expression were measured in sperm samples as potential causes of the changes in the seminogram. Results: Compared with the control group, improvements in total sperm count (P = 0.002) and vitality (P = 0.003), total motility (P = 0.006), progressive motility (P = 0.036), and morphology of sperm (P = 0.008) were observed in the nut group. Participants in the nut group showed an increase in the consumption of total fat, monounsaturated fatty acids, polyunsaturated fatty acids, magnesium, vitamin E, α-linolenic acid, total omega-3 (n–3) and ω-3: ω-6 ratio intake during the intervention. Participants in the nut group showed a significant reduction in SDF (P < 0.001) and in the expression of hsa-miR-34b-3p (P = 0.036). No significant changes in ROS, sperm chromosome anomalies, or DNA methylation were observed between groups. Conclusions: The inclusion of nuts in a Western-style diet significantly improves the total sperm count and the vitality, motility, and morphology of the sperm. These findings could be partly explained by a reduction in the sperm DNA fragmentation. This trial was registered at ISRCTN as ISRCTN12857940.

Effect of nut consumption on vascular endothelial function: A systematic review and meta-analysis of randomized controlled trials.

Xiao, Y., W. Huang, C. Peng, J. Zhang, C. Wong, J.H. Kim, E.-K. Yeoh, 2017. Effect of nut consumption on vascular endothelial function: A systematic review and meta-analysis of randomized controlled trials. Clinical Nutrition. http://dx.doi.org/10.1016/j.clnu.2017.04.011

Objective: Nut consumption has consistently been found to be associated with a reduced risk of cardiovascular diseases (CVD) and mortality in prospective studies. However, its effect on endothelial function, a prognostic marker of CVD, is still controversial in clinical trials. This meta-analysis of randomized controlled trials (RCTs) aimed to quantitatively assess the effect of nuts on vascular endothelial function. Methods: Major electronic databases were searched for published RCTs that reported the effect of nuts on flow mediated dilation (FMD) as a measurement of endothelial function in the adult population (age eighteen years or over). We calculated the pooled estimates of weighted mean differences (WMDs) and their 95% confidence intervals (CIs) by using random-effects models. Results: A total of nine papers (10 trials) involving 374 participants were included. The pooled estimates found that nut consumption significantly improved FMD (WMD: 0.41%; 95% CI: 0.18%, 0.63%; P = 0.001). Moderate and marginally significant heterogeneity was observed among the studies (I2 = 39.5%, P = 0.094). Subgroup analyses indicated that walnuts significantly improved FMD (WMD: 0.39%; 95% CI: 0.16%, 0.63%; P = 0.001). In addition, nut consumption had a significant effect on FMD in the trials with study duration <18 weeks, nut dose <67 g/d, or subjects with baseline FMD ≥8.6%. Conclusions: Nut consumption significantly improved endothelial function. However, the beneficial effect was limited to walnuts. More studies examining the effect of other nuts on endothelial function are needed in the future.