Nut intake and adiposity: meta-analysis of clinical trials

Unitat de Suport a la Recerca Tarragona-Reus, Institut Universitari d'Investigació en Atenció Primària Jordi Gol, Tarragona, Spain.
American Journal of Clinical Nutrition (Impact Factor: 6.5). 04/2013; 97(6). DOI: 10.3945/ajcn.111.031484
Source: PubMed

ABSTRACT BACKGROUND: Epidemiologic studies have shown an inverse association between the frequency of nut consumption and body mass index (BMI) and risk of obesity. However, clinical trials that evaluated nut consumption on adiposity have been scarce and inconclusive. OBJECTIVE: We performed a systematic review and meta-analysis of published, randomized nut-feeding trials to estimate the effect of nut consumption on adiposity measures. DESIGN: MEDLINE and the Cochrane Central Register of Controlled Trials databases were searched for relevant clinical trials of nut intake that provided outcomes of body weight, BMI (in kg/m(2)), or waist-circumference measures and were published before December 2012. There were no language restrictions. Two investigators independently selected and reviewed eligible studies. The weighted mean difference (WMD) between nut or control diets was estimated by using a random-effects meta-analysis with 95% CIs. RESULTS: Thirty-one clinical trials met our inclusion criteria. Pooled results indicated a nonsignificant effect on body weight (WMD: -0.64 kg; 95% CI: -2.32, 1.05 kg; I(2) = 99%), BMI (WMD: -0.30; 95% CI: -0.92, 0.32; I(2) = 98%), or waist circumference (WMD: -1.10 cm; 95% CI: -3.34, 1.14 cm; I(2) = 96%) of diets including nuts compared with control diets. These findings were remarkably robust in the sensitivity analysis. No publication bias was shown. CONCLUSION: Compared with control diets, diets enriched with nuts did not increase body weight, body mass index, or waist circumference in controlled clinical trials.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Evidence consistently shows that almond consumption beneficially affects lipids and lipoproteins. Almonds, however, have not been evaluated in a controlled-feeding setting using a diet design with only a single, calorie-matched food substitution to assess their specific effects on cardiometabolic risk factors. In a randomized, 2-period (6 week/period), crossover, controlled-feeding study of 48 individuals with elevated LDL-C (149±3 mg/dL), a cholesterol-lowering diet with almonds (1.5 oz. of almonds/day) was compared to an identical diet with an isocaloric muffin substitution (no almonds/day). Differences in the nutrient profiles of the control (58% CHO, 15% PRO, 26% total fat) and almond (51% CHO, 16% PRO, 32% total fat) diets were due to nutrients inherent to each snack; diets did not differ in saturated fat or cholesterol. The almond diet, compared with the control diet, decreased non-HDL-C (-6.9±2.4 mg/dL; P=0.01) and LDL-C (-5.3±1.9 mg/dL; P=0.01); furthermore, the control diet decreased HDL-C (-1.7±0.6 mg/dL; P<0.01). Almond consumption also reduced abdominal fat (-0.07±0.03 kg; P=0.02) and leg fat (-0.12±0.05 kg; P=0.02), despite no differences in total body weight. Almonds reduced non-HDL-C, LDL-C, and central adiposity, important risk factors for cardiometabolic dysfunction, while maintaining HDL-C concentrations. Therefore, daily consumption of almonds (1.5 oz.), substituted for a high-carbohydrate snack, may be a simple dietary strategy to prevent the onset of cardiometabolic diseases in healthy individuals.; Unique Identifier: NCT01101230. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
    Journal of the American Heart Association 12/2015; 4(1). DOI:10.1161/JAHA.114.000993
  • [Show abstract] [Hide abstract]
    ABSTRACT: Regular nut consumption is associated with reduced CVD risk. Insight into nut consumption patterns provides important information to help design strategies to encourage intake. The present study aimed to describe nut consumption in terms of the percentage of consumers, mean grams eaten among the population and nut consumers, and to identify the predictors of nut consumption. Data from the 24 h dietary recalls of the 2008/09 New Zealand Adult Nutrition Survey (n 4721) were used to measure nut consumption. On the recall day, the percentages of consumers of whole nuts, nut butters and nuts from hidden sources were 6·9 % (n 240), 7·2 % (n 346) and 19·2 % (n 732), respectively (28·9 % (n 1167) combined (total)). The mean grams consumed by the population were relatively low for whole nuts (2·8 g/d), nut butters (0·9 g/d), nuts from hidden sources (1·5 g/d) and total nuts (5·2 g/d). Among consumers, the mean daily grams of whole nuts, nut butters, nuts from hidden sources and total nuts eaten were 40·3, 12·9, 7·8 and 17·9 g/d, respectively. Those aged 15-18 years had the lowest whole nut consumption, but had the highest nut butter consumption. The consumption of total nuts was positively associated with education and socio-economic status, while whole nut consumption was inversely associated with BMI. In conclusion, the low percentage of nut consumers is of concern and new strategies to increase nut consumption are required. Future public health initiatives should be mindful of these patterns and predictors. In particular, different forms of nuts may appeal to different age and socio-economic groups.
    British Journal Of Nutrition 10/2014; 112(12):1-13. DOI:10.1017/S0007114514003158 · 3.34 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Snack foods can contribute a high proportion of energy intake to the diet. Peanuts are a snack food rich in unsaturated fatty acids, protein and fibre which have demonstrated satiety effects and may reduce total energy intake, despite their high energy density. This study examined the effects of consuming Hi-oleic (oleic acid ~75% of total fatty acids) peanuts and regular peanuts (oleic acid ~ 50% and higher in polyunsaturated fatty acids) compared with a high carbohydrate snack (potato crisps) on satiety and subsequent energy intake. Using a triple crossover study design, 24 participants (61±1 years) consumed iso-energetic amounts (56-84g) of Hi-oleic or regular peanuts or (60-90g) potato crisps after an overnight fast. Hunger and satiety were assessed at baseline, 30, 60, 120 and 180 minutes following snack consumption using visual analogue scales, after which a cold buffet meal was freely consumed and energy intake measured. The same snack was consumed on 3 subsequent days with energy intake assessed from dietary records. This protocol was repeated weekly with each snack food. Total energy intake was lower following consumption of Hi-oleic and regular peanuts compared with crisps, both acutely during the buffet meal (-21%; p < .001 and -17%; p < .01) and over the 4 days (-11%; p < .001 and -9%; p < .01). Despite these reductions in energy intake, no differences in perceived satiety were observed. The findings suggest peanuts may be a preferred snack food to include in the diet for maintaining a healthy weight.
    Appetite 07/2014; 82. DOI:10.1016/j.appet.2014.07.015 · 2.52 Impact Factor


Available from
Sep 30, 2014