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Almond polyphenols: methods of analysis, contribution to food quality, and health promotion.

Bolling, B.W., 2017. Almond polyphenols: methods of analysis, contribution to food quality, and health promotion. Comprehensive Reviews In Food Science And Food Safety; doi: 10.1111/1541-4337.12260.

Almond is a nutrient-dense tree nut recognized for its favorable lipid profile, vitamin E content, and polyphenols. The objectives of this review were to determine the polyphenols reported in almond, summarize the methods of analysis, and determine the polyphenol contribution to almond quality and health-promoting activity. Approximately 130 different polyphenols have been identified in almond, although not all of these have been quantitated. The mean and 25% to 75% percentile contents reported in literature were 162 mg (67.1 to 257) proanthocyanidins (dimers or larger), 82.1 mg (72.9 to 91.5) hydrolysable tannins, 61.2 mg (13.0 to 93.8) flavonoids (non-isoflavone), 5.5mg(5.2to12) phenolic acids and aldehydes, and 0.7mg (0.5to0.9) isoflavones, stilbenes, and lignans per100g almond. Following solvent extraction of almond, hydrolysis of the residue liberates additional proanthocyanidins, phenolic acids andaldehydes, and total phenols. Blanching and skin removal consistently reduces almond polyphenol content, but blanch water and almond skins retain enough polyphenols to be used as antimicrobial and antioxidant ingredients. Roasting and pasteurization have inconsistent effects on almond polyphenols. Almond polyphenols contribute to shelf life by inhibiting lipid oxidation and providing pigmentation, flavor, astringency, and antimicrobial activity. The health-promoting activity of whole almonds has been widely investigated, but few have considered the contribution of polyphenols. Preclinical studies of polyphenol-rich almond skin or almond extracts suggest putative effects on antioxidant function, detoxification, antiviral activity, anti-inflammatory function, and topical use for inhibiting ultraviolet A damage. Therefore, almond has a diverse polyphenol profile contributing to both its food quality and health-promoting actions.

Effects of almond consumption on the post-lunch dip and long-term cognitive function in energy-restricted overweight and obese adults.

Dhillon, J., S.-Y. Tan, R.D. Mattes, 2017. Effects of almond consumption on the post-lunch dip and long-term cognitive function in energy-restricted overweight and obese adults. Br. J. Nutr. doi:10.1017/S0007114516004463.

The post-lunch dip in cognition is a well-established phenomenon of decreased alertness, memory and vigilance after lunch consumption. Lunch composition reportedly influences the post-lunch dip. Moreover, dieting is associated with cognitive function impairments. The negative effects of dieting have been reversed with nut-supplemented diets. The aims of this study were to (1) evaluate the acute effect of an almond-enriched high-fat lunch or high-carbohydrate lunch on the post-lunch decline in cognitive function, and (2) evaluate the effects of chronic almond consumption as part of an energy-restricted diet on the memory and attention domains of cognitive function. In total, eighty-six overweight and obese adults were randomised to consume either an almond-enriched diet (AED) or a nut-free control diet (NFD) over a 12-week weight loss intervention. Participants were also randomised to receive either an almond-enriched high-fat lunch (A-HFL) (>55% energy from fat, almonds contributing 70–75% energy) or a high-carbohydrate lunch (HCL) (>85% energy from carbohydrates) at the beginning and end of the weight loss intervention. Memory and attention performance indices decreased after lunch consumption (P<0·001). The A-HFL group ameliorated the decline in memory scores by 57·7% compared with the HCL group (P=0·004). Both lunch groups had similar declines in attention. Moreover, memory and attention performance indices increased after the 12-week intervention period (P<0·05) with no difference between the AED and NFD groups. In conclusion, almond consumption at a midday meal can reduce the post-lunch dip in memory. However, long-term almond consumption may not further improve cognitive function outcomes in a weight loss intervention.

Key words: Cognitive function: Post-lunch dip: Almonds: Nuts: Energy restriction

Inclusion of almonds in a cholesterol-lowering diet improves plasma HDL subspecies and cholesterol efflux to serum in normal-weight individuals with elevated LDL cholesterol.

Berryman, C.E, J.A. Fleming, P.M. Kris-Etherton, 2017. Inclusion of almonds in a cholesterol-lowering diet improves plasma HDL subspecies and cholesterol efflux to serum in normal-weight individuals with elevated LDL cholesterol. J. Nutr. 147(8). doi: 10.3945/jn.116.245126.

Background: Almonds may increase circulating HDL cholesterol when substituted for a high-carbohydrate snack in an isocaloric diet, yet little is known about the effects on HDL biology and function. Objective: The objective was to determine whether incorporating 43 g almonds/d in a cholesterol-lowering diet would improve HDL subspecies and function, which were secondary study outcomes. Methods: In a randomized, 2-period, crossover, controlled-feeding study, a diet with 43 g almonds/d (percentage of total energy: 51% carbohydrate, 16% protein, and 32% total and 8% saturated fat) was compared with a similar diet with an isocaloric muffin substitution (58% carbohydrate, 15% protein, and 26% total and 8% saturated fat) in men and women with elevated LDL cholesterol. Plasma HDL subspecies and cholesterol efflux from J774 macrophages to human serum were measured at baseline and after each diet period. Diet effects were examined in all participants (n = 48) and in normal weight (body mass index: <25; n = 14) and overweight or obese (≥25; n = 34) participants by using linear mixed models. Results: The almond diet, compared with the control diet, increased α-1 HDL [mean ± SEM: 26.7 ± 1.5 compared with 24.3 ± 1.3 mg apolipoprotein A-I (apoA-I)/dL; P = 0.001]. In normal-weight participants, the almond diet, relative to the control diet, increased a-1 HDL (33.7 6 3.2 compared with 28.4 ± 2.6 mg apoA-I/dL), the α-1 to pre–β-1 ratio [geometric mean (95%CI): 4.3 (3.3, 5.7) compared with 3.1 (2.4,4.0)], and non–ATP-binding cassette transporter A1 cholesterol efflux (8.3% ± 0.4% compared with 7.8% ± 0.3%) and decreased pre–β-2 (3.8 ± 0.4 compared with 4.6 ± 0.4 mg apoA-I/dL) and α-3 (23.5 ± 0.9 compared with 26.9 ± 1.1 mg apoA-I/dL) HDL (P < 0.05). No diet effects were observed in the overweight or obese group. Conclusions: Substituting almonds for a carbohydrate-rich snack within a lower-saturated-fat diet may be a simple strategy to maintain a favorable circulating HDL subpopulation distribution and improve cholesterol efflux in normal-weight individuals with elevated LDL cholesterol.

The effect of almonds on vitamin E status and cardiovascular risk factors in Korean adults: a randomized clinical trial.

Jung, H., C.Y.O. Chen, J.B. Blumberg, H.K. Kwak, 2017. The effect of almonds on vitamin E status and cardiovascular risk factors in Korean adults: a randomized clinical trial. Eur. J. Nutr. doi:10.1007/s00394-0171480-5.

Purpose: Almonds have shown to beneficially modify some cardiovascular risk factors in clinical trials conducted in diverse ethnic populations but this relationship has never been tested in Koreans. Thus, we tested the impact of almonds consumed as a snack within the context of a typical Korean diet on cardiovascular risk factors. Methods: We conducted a randomized, crossover trial in a free-living setting with a 2-week run-in period, two 4-week intervention phases, and a 2-week washout period between interventions. Eighty-four overweight/obese participants (11 M/73 F; 52.4 ± 0.6 year; 25.4 ± 0.22 kg/m2) consumed either 56 g of almonds or isocaloric cookies daily for 4 weeks. Results: Mean % daily energy intake at baseline was 64.8, 21.3, and 14.9% from carbohydrate, fat, and protein, respectively. The addition of 56 g of almonds daily decreased carbohydrate energy to 55.0%, increased fat to 32.0%, and maintained protein at 14.7%. Consuming the almonds increased intake of MUFA by 192.3%, PUFA by 84.5%, vitamin E by 102.7%, and dietary fiber by 11.8% and decreased % energy from carbohydrate by 14.1%. Total caloric intake was increased by the almonds, but body weight, waist circumference, and body composition were not affected. Almonds in overweight and obese Korean adults decreased TC, LDL-C, and non-HDL-C by 5.5, 4.6, and 6.4%, respectively, compared to the cookie control (P ≤ 0.05). Almonds increased plasma α-tocopherol by 8.5% (P ≤ 0.05) from the baseline and tended to increase its value as compared to cookies (P = 0.055). Neither the almonds nor cookies altered plasma protein carbonyls, MDA or oxLDL. Of serum inflammatory markers, IL-10 was decreased by almond intake (P ≤ 0.05), and ICAM1, IL-1β, and IL-6 tended to be lower with almonds, compared to the cookies. Conclusions: Almonds at 56 g/day consumed as a snack favorably modified the Korean diet by increasing MUFA, PUFA, vitamin E, and dietary fiber intake and decreasing % energy intake from carbohydrate. Almonds also enhanced plasma α-tocopherol status and serum TC and LDL-C in overweight and obese Koreans. Thus, including almonds in typical Korean diets as a snack can help healthy overweight/obese individuals improve nutritional status and reduce their risk for CVD.