Yang, J., R. Lee, Z. Schulz, A. Hsu, J. Pai, S. Yang, S.M. Henning, J. Huang, J.P. Jacobs, D. Heber, Z. Li., 2023. Mixed Nuts as Healthy Snacks: Effect on Tryptophan Metabolism and Cardiovascular Risk Factors. Nutrients. 15, 569; https://doi.org/10.3390/nu15030569.
We recently demonstrated that the consumption of mixed tree nuts (MTNs) during caloric restriction decreased cardiovascular risk factors and increased satiety. Tryptophan (Trp) metabolism has been indicated as a factor in cardiovascular disease. Here, we investigated the effect of MTNs on Trp metabolism and the link to cardiovascular risk markers. Plasma and stool were collected from 95 overweight individuals who consumed either MTNs (or pretzels) daily as part of a hypocaloric weight loss diet for 12 weeks followed by an isocaloric weight maintenance program for an additional 12 weeks. Plasma and fecal samples were evaluated for Trp metabolites by LC–MS and for gut microbiota by 16S rRNA sequencing. Trp–kynurenine metabolism was reduced only in the MTNs group during weight loss (baseline vs. week 12). Changes in Trp–serotonin (week 24) and Trp–indole (week 12) metabolism from baseline were increased in the MTNs group compared to the pretzel group. Intergroup analysis between MTN and pretzel groups does not identify significant microbial changes as indicated by alpha diversity and beta diversity. Changes in the relative abundance of genus Paludicola during intervention are statistically different between the MTNs and pretzel group with p < 0.001 (q = 0.07). Our findings suggest that consumption of MTNs affects Trp host and microbial metabolism in overweight and obese subjects.
Cong, W., K. Gu, F. Wang, H. Cai, W. Zheng, P. Bao, X.-O. Shu, 2022. Nut consumption in association with overall mortality and recurrence/disease-specific mortality among long-term breast cancer survivors. International Journal of Cancer.doi.org/10.1002/ijc.33824.
High nut consumption is associated with reduced total and certain cause-specific mortality in general populations. However, its association with cancer outcomes among long-term breast cancer survivors remains unknown. We examined the associations of nut consumption (including peanuts and tree nuts), assessed at 5-year postdiagnosis, with overall survival (OS) and disease-free survival (DFS) among 3449 long-term breast cancer survivors from the Shanghai Breast Cancer Survival Study, applying Cox regression analysis. During a median follow-up of 8.27 years post dietary assessment, there were 374 deaths, including 252 breast cancer deaths. Among 3274 survivors without previous recurrence at the dietary assessment, 209 developed breast cancer-specific events, that is, recurrence, metastasis or breast cancer mortality. At 5-year post dietary assessment (ie, 10-year postdiagnosis), regular nut consumers had higher OS (93.7% vs 89.0%) and DFS (94.1% vs 86.2%) rates. After multivariable adjustment, nut consumption was positively associated with OS (Ptrend = .022) and DFS (Ptrend = .003) following a dose-response pattern, with hazard ratios (95% confidence interval) of 0.72 (0.52-1.05) for OS and 0.48 (0.31-0.73) for DFS, for participants with greater than median nut intake compared with nonconsumers. The associations did not vary by nut type. Stratified analyses showed that the associations were more evident among participants with a higher total energy intake for OS (Pinteraction = .02) and among participants with early stage (I-II) breast cancers for DFS (Pinteraction = .04). The nut-DFS associations were not modified by estrogen receptor/progesterone receptor status or other known prognostic factors. In conclusion, nut consumption was associated with better survival, particularly DFS, among long-term breast cancer survivors.
Xia, J.Y., J.H. Yu, D.F. Xu, C. Yang, H. Xia, G.J. Sun, 2021. The effects of peanuts and tree nuts on lipid profile in Type 2 diabetic patients: A systematic review and meta-analysis of randomized, controlled-feeding clinical studies. Front. Nutr. https://doi.org/10.3389/fnut.2021.765571
Background: Type 2 diabetes mellitus was found to be associated with metabolic disorders, particularly abnormal glucose and lipid metabolism. Dietary food choices may have profound effects on blood lipids. The primary objective of this study was to examine the effects of peanuts and tree nuts intake on lipid profile in patients with type 2 diabetes. Methods: According to preferred reporting items for systematic reviews and meta-analysis guidelines, we performed a systematic search of randomized controlled clinical trials and systematic reviews published in PubMed, Web of Science, Embase, Scopus, and Cochrane library, from inception through June 2021. Studies in populations with type 2 diabetes, which compare nuts or peanuts to a controlled-diet group were included. We used the mean difference with 95% CIs to present estimates for continuous outcomes from individual studies. In addition, we used the GRADEpro tool to evaluate the overall quality of evidence. Results: Sixteen studies involving 1,041 participants were eligible for this review. The results showed that peanuts and tree nuts supplementation did not induce significant changes in low-density lipoprotein-cholesterol (LDL-C) (mean difference = −0.11; 95%CI: −0.25 – 0.03, p = 0.117) and high-density lipoprotein-cholesterol (HDL-C) (mean difference = 0.01; 95%CI: −0.01 – 0.04, p = 0.400) in patients with type 2 diabetics. In addition, we found that peanuts and tree nuts intake may cause a significantly reduction in total cholesterol (TC) (mean difference = −0.14; 95%CI: −0.26 – −0.02, p = 0.024) and triglyceride (TG) (mean difference = −0.10; 95%CI: −0.17 – −0.02, p = 0.010). In the subgroup analysis, a significantly greater reduction in TC was observed in studies which duration was <12 weeks (mean difference = −0.22; 95%CI: −0.37 – −0.08, p = 0.002). The quality of the body of evidence was “moderate” for TC and TG, the quality of evidence for LDL-C and HDL-C were “low.” Conclusion: Our findings suggest that consuming peanuts and tree nuts might be beneficial to lower TC concentration and TG concentration in type 2 diabetics subjects. Furthermore, peanuts and tree nuts supplementation could be considered as a part of a healthy lifestyle in the management of blood lipids in patients with type 2 diabetes. Given some limits observed in the current studies, more well-designed trials are still needed.
Fatahi, S., E. Daneshzad. K. Lotfi, L. Azadbakht, 2021. The effects of almond consumption on inflammatory biomarkers in adults: A systematic review and meta-analysis of randomized clinical trials. Adv. Nutr. doi:10.1093/advances/nmab158.
Conflicting findings have been reported regarding the effects of almond consumption on inflammatory markers. This study aimed to summarize the current literature to determine whether almond can affect inflammatory markers. A systematic search was carried out in PubMed, Scopus, and ISI Web of Science up to March 2021. Randomized clinical trials (RCTs) that compared almond with no almond consumption were included. The outcomes of interest were changes in circulating C-reactive protein (CRP), Interleukin-6 (IL-6), Tumor Necrosis Factor Alpha (TNF-α), Intercellular Adhesion Molecule-1 (ICAM-1) and Vascular Cell Adhesion Molecule-1 (VCAM-1) concentrations. The random-effects model was used to find the mean differences. Totally, 18 trials with 847 participants were eligible for the current analysis. Participant age ranged from 26.3 to 69.6 y. Combining 16 studies, almond consumption significantly reduced serum levels of CRP (WMD: -0.25 mg/L; 95% CI: -0.43, -0.06; I2 = 0.0% P-heterogeneity = 0.633). However, the beneficial effect of almond intake only occurred at doses <60 g/d. Pooling 11 effect sizes, almond interventions significantly decreased circulating IL-6 concentrations (WMD: -0.11 pg/mL; 95% CI: -0.21, -0.01; I2 = 19.9% P-heterogeneity = 0.254). In subgroup analyses, effects on CRP and IL-6 were not significant in unhealthy participants or those with obesity. In addition, almond consumption had no significant effect on TNF-α (WMD: -0.05 pg/mL; 95% CI: -0.11, 0.01; I2 = 0.0% P-heterogeneity = 0.893; n = 6), ICAM-1 (WMD: 6.39 ng/mL; 95% CI: -9.44, 22.22; I2 = 66.6% P-heterogeneity = 0.006; n = 7) or VCAM-1 (WMD: -8.31 ng/mL; 95% CI: -35.32, 18.71; I2 = 58.8% P-heterogeneity = 0.033; n = 6). In conclusion, almond consumption beneficially affects CRP and IL-6 concentrations in adults. However, it has no beneficial effect on TNF-α, ICAM-1, or VCAM-1. More trials are needed to determine the effects of almond on inflammation.
Nishi, S.K., E. Viguiliouk, S. Blanco Mejia, C.W.C. Kendall, R.P. Bazinet, A.J. Hanley, E.M. Comelli, J. Salas Salvado, D.J.A. Jenkins, J.L. Sievenpiper, 2021. Are fatty nuts a weighty concern? A systematic review and meta-analysis and dose–response meta-regression of prospective cohorts and randomized controlled trials. Obes Rev. doi: 10.1111/obr.13330.
Nuts are recommended for cardiovascular health, yet concerns remain that nuts may contribute to weight gain due to their high energy density. A systematic review and meta-analysis of prospective cohorts and randomized controlled trials (RCTs) was conducted to update the evidence, provide a dose-response analysis, and assess differences in nut type, comparator and more in subgroup analyses. MEDLINE, EMBASE, and Cochrane were searched, along with manual searches. Data from eligible studies were pooled using meta-analysis methods. Interstudy heterogeneity was assessed (Cochran Q statistic) and quantified (I2 statistic). Certainty of the evidence was assessed by Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Six prospective cohort studies (7 unique cohorts, n = 569,910) and 86 RCTs (114 comparisons, n = 5873) met eligibility criteria. Nuts were associated with lower incidence of overweight/obesity (RR 0.93 [95% CI 0.88 to 0.98] P < 0.001, “moderate” certainty of evidence) in prospective cohorts. RCTs presented no adverse effect of nuts on body weight (MD 0.09 kg, [95% CI -0.09 to 0.27 kg] P < 0.001, “high” certainty of evidence). Meta-regression showed that higher nut intake was associated with reductions in body weight and body fat. Current evidence demonstrates the concern that nut consumption contributes to increased adiposity appears unwarranted.
Wang, J., S. Wang, S.M. Henning, T. Qin, Y. Pan, J. Yang, J. Huang, C.-H. Tseng, D. Heber, Z. Li, 2021. Mixed tree nut snacks compared to refined carbohydrate snacks resulted in weight loss and increased satiety during both weight loss and weight maintenance: A 24-week randomized controlled trial. Nutrients. 13(5), 1512; doi.org/10.3390/nu13051512
Mixed tree nuts (MTNs) are an excellent source of protein and healthy fat contributing to satiety. However, their relatively high caloric content might not be beneficial in a weight loss diet. The present study was designed to test whether including MTNs in a weight loss and maintenance program interferes with weight management compared to a refined carbohydrate pretzel snack (PS). We performed a randomized, controlled, two-arm study in 95 overweight individuals consuming 1.5 oz of MTNs or PS daily as part of a hypocaloric weight loss diet (−500 kcal) over 12 weeks followed by an isocaloric weight maintenance program for 12 weeks. Participants in both groups experienced significant weight loss (12 weeks: −1.6 and −1.9 and 24 weeks: −1.5 and −1.4 kg) compared to baseline in the MTN and PS groups, respectively. However, there was no difference in weight loss and other outcome parameters between the MTN and PS groups. The MTN group showed a significant increase in satiety at 24 weeks. Both groups had a decrease in diastolic blood pressure at 12 weeks. Participants in the MTN group showed significant decreases in heart rate at 4, 12, and 24 weeks. Plasma oleic acid was significantly increased at 12 and 24 weeks in the MTN group but only at 12 weeks in the PS group. Plasma MCP-1 was decreased significantly in the MTN group at 4 weeks. In summary, participants in both groups lost weight, but only the MTN intervention increased satiety at 24 weeks, enhanced retention, decreased heart rate, and increased serum oleic acid at 24 weeks.
Park, S.K., C.-M. Oh, J.G. Kang, H.S. Seok, J.Y. Jung, 2021. The association between left ventricular hypertrophy and consumption of nuts, including peanuts, pine nuts, and almonds. Nutr Metab Cardiovasc Dis. 31(1):76-84.
Background and aims: Studies have reported that nut consumption is potentially beneficial in preventing cardiovascular disease. However, data are insufficient regarding the association between nut consumption and left ventricular hypertrophy (LVH). Methods and results: In the Kangbuk Samsung Health Study, the participants were 34,617 men and 12,257 women who completed a food-frequency questionnaire for nut consumption and received echocardiography. Nut consumption was evaluated only for peanuts, pine nuts, and almonds defining 15g as one serving/servings dose. Multivariable adjusted odds ratio (OR) and 95% confidence interval (CI) for LVH were evaluated according to the consumption frequency of one serving dose of nut. The frequency of nut consumption was categorized into five groups (<1/month, 1/month-1/week, 1-2/week, 2-4/week, and ≥4/week). The subgroup analysis was conducted by dividing the participants into the following two groups: the nonhypertensive/nondiabetic group and hypertensive or diabetic group. In women, nut consumption ≥2/week had the lower multivariable adjusted OR and 95% CI for LVH (2-4/week: 0.46 [0.26-0.81] and ≥4/week: 0.48 [0.25-0.92]) when compared with nut consumption <1/month. This association was identically observed in the subgroup analysis for women without hypertension and diabetes mellitus (DM) and women with hypertension or DM. However, men did not show the significant association. Conclusion: In women, nut consumption ≥2/week was associated with the decreased probability of LVH. Further research studies should investigate whether the beneficial effect of nut consumption on LV structure results in better cardiovascular prognosis.
Rybak, I., A.E. Carrington, S. Dhaliwal, A. Hasan, H. Wu, W. Burney, J. Maloh, R.K. Sivamani, 2021. Prospective randomized controlled trial on the effects of almonds on facial wrinkles and pigmentation. Nutrients. 13,785. doi.org/10.3390/nu13030785
Background: Almonds have long been studied as a rich source of fatty acids, phytochemical polyphenols and antioxidants such as vitamin E. A recent study compared almond supplementations to a calorie-matched intervention for 16 weeks, yielding statistically significant improvement in wrinkle severity in postmenopausal women with Fitzpatrick skin types I and II that received almonds. This study furthers that assessment with a larger population and duration of 24 weeks to assess the influence of almond consumption on wrinkle severity, skin pigmentation and other skin biophysical profiles. Objective: To investigate the effects of almond consumption on photoaging such as wrinkles and pigment intensity as well as facial biophysical parameters such as sebum production, skin hydration and water loss. Design and interventions: A prospective, randomized controlled study assessed postmenopausal women with Fitzpatrick skin types I or II who consumed 20% of their daily energy consumption in either almonds or a calorie-matched snack for 24 weeks. A facial photograph and image analysis system was used to obtain standardized high-resolution photographs and information on wrinkle width and severity at 0, 8, 16 and 24 weeks. Measurements of transepidermal water loss (TEWL), skin pigmentation, skin hydration and sebum production were also completed at each visit. Results: The average wrinkle severity was significantly decreased in the almond intervention group at week 16 and week 24 compared to baseline by 15% and 16%, respectively. Facial pigment intensity was decreased 20% in the almond group at week 16 and this was maintained by week 24. There were no significant differences in skin hydration or TEWL in the almond group compared to the control, although sebum excretion was increased in the control group. Conclusion: The daily consumption of almonds may improve several aspects of photoaging such as facial wrinkles and pigment intensity in postmenopausal women. In conclusion, the daily consumption of almonds may contribute to the improvement of facial wrinkles and reduction of skin pigmentation among postmenopausal women with Fitzpatrick skin types I and II.
Li, J.N., S.M. Henning, G. Thames, O. Bari, P.T. Tran, C.-H. Tseng, D. Heber, J. Kim, Z. Li, 2021. Almond consumption increased UVB resistance in healthy Asian women. J Cosmet Dermatol. 00:1–6.
Background: Almonds are a rich source of phenolic and polyphenolic compounds, which have antioxidant activity. In vitro and in vivo studies have demonstrated that topical application of almond oil and almond skin extract reduces UVB-induced photoaging. Ultraviolet-B (UVB) protection by oral almond consumption has not been previously studied in humans. Objectives: To investigate whether oral almond consumption can increase resistance to UVB radiation and reduce skin aging in healthy Asian women. Methods: Thirty-nine female participants (18-45 years) with Fitzpatrick skin type II-IV were randomly assigned to consume either 1.5 oz of almonds or 1.8 oz of pretzels daily for 12 weeks. Minimal erythema dose (MED) was determined using a standardized protocol, which determined the minimal radiation needed to induce erythema on the inner arm following UVB exposure. Facial skin texture was evaluated by two dermatologists using the Clinician’s Erythema Assessment scale and Allergan Roughness scale. Facial melanin index, hydration, sebum, and erythema were determined using a cutometer. Results: The MED was increased in the subjects consuming almonds compared to the control group consuming pretzels. There were no differences noted between the groups consuming almonds versus pretzels in Allergan roughness, melanin, hydration, or sebum on facial skin. Conclusions: Our findings suggest that daily oral almond consumption may lead to enhanced protection from UV photodamage by increasing the MED.
Rakic, J.M., J. Tanprasertsuk, T.M. Scott, H.M. Rasmussen, E.S. Mohn, C.-Y.O. Chen, E.J. Johnson, 2021. Effects of daily almond consumption for six months on cognitive measures in healthy middle-aged to older adults: a randomized control trial. Nutr Neurosci. 1-11. doi: 10.1080/1028415X.2020.1868805.
Background: Age-related cognitive decline is a major public health issue. Almonds are rich in nutrients that benefit cognitive function. Objective: To investigate the impact of almonds on cognition in elderly adults. Design: In a six-month, single-blinded, randomized-controlled trial, the effects of an almond intervention on cognition in healthy, middle-aged/older adults (50-75 years) was tested. Subjects were assigned to one of three groups: 1.5 oz/d almond (n = 19), 3 oz/d almond (n = 24), or 3.5 oz/d snack (control, matched for macronutrients in 3.0 oz almonds, (n = 17). Serum analyses for tocopherols, oxidative status and inflammation, and cognition were assessed at baseline (M0), three (M3), and six (M6) months. Results: At M6, serum alpha-tocopherol concentrations increased by 8% from M0 (p < 0.05) in the 3 oz almond group but did not increase in the other groups. Serum markers of inflammation and oxidative stress were not significantly different throughout the study among the groups. There was no difference in change over time in cognitive tests among the groups. However, there was a significant improvement in visuospatial working memory (p = 0.023), visual memory and learning (p = 0.017), and spatial planning and working memory (p < 0.001) in subjects receiving 3 oz/d almonds at M6, while the snack group showed no improvement. Conclusions: Almonds did not significantly improve cognitive function in cognitively intact middle-aged/older adults over six months. However, a significant improvement at M6 in cognitive measures was observed with 3 oz/d almonds. While these results are encouraging, a study of longer duration in subjects at risk for age-related cognitive decline is warranted.