Effects of energy-restricted diets with or without nuts on weight, body composition and glycaemic control in adults: a scoping review

Energy-restricted (ER) diets promote weight loss and improve body composition and glycaemic control. Nut consumption also improves these parameters. However, less is known about the combined benefit of these two strategies. This scoping review implemented a systematic search of Medline, Embase and Scopus to identify randomised controlled trials evaluating the effect of ER diets with or without nuts on body mass, body composition and glycaemic control in adults. After reviewing titles and abstracts, twenty-nine full-text articles were screened, resulting in seven studies reported in eight papers that met the inclusion criteria. Energy restriction was achieved by prescribing a set energy target or reducing intake by 1000-4200 kJ from daily energy requirements. Interventions ranged from 4 to 52 weeks in duration and contained 42-84 g/d of almonds, peanuts, pistachios or walnuts. While all studies reported that energy restriction resulted in significant weight loss, the addition of nuts to ER diets demonstrated significantly greater weight loss in only approximately half of the included studies (4/7 studies). There was limited evidence to support additional benefits from nuts for body composition measures or glycaemic control. Although improvements in weight loss and glycaemia were not consistent when nuts were included in ER diets, no study revealed an adverse effect of nut consumption on health outcomes. Future studies could explore the effect of consuming different types and amounts of nuts, combined with various levels of energy restriction on weight, body composition and glycaemic control. https://doi.org/10.1017/S0954422424000106


Association of legumes and nuts consumption with metabolic health status in Iranian overweight and obese adolescents

Limited data are available on the association of legumes and nuts consumption with health status in pediatrics. So, we assessed the relation of legumes and nuts intake with metabolic health status in Iranian adolescents. A random sample of overweight/obese adolescents aged 12 to 18 years was included in this cross-sectional study. Dietary intakes were gathered using a validated 147-item food frequency questionnaire (FFQ). We measured metabolic indices including blood pressure, lipid profile, glycemic and anthropometrics indices. Two strategies were used for classification of adolescents to metabolically healthy obese (MHO) or unhealthy obese (MUO): International Diabetes Federation (IDF) and combination of IDF with Homeostasis Model Assessment Insulin Resistance (HOMA-IR). Information on 203 overweight/obese adolescents (50.2% girls and 49.8% boys) with an average age of 13.98 (± 1.61) years and a mean weight of 73.48 (± 11.60) kg/m2 was evaluated. Based on the IDF and IDF/HOMA-IR definition, higher consumption of legumes and nuts consumption was related to a 66% and 61% decreased odds of MUO in crude model (OR = 0.34, 95%CI 0.17–0.69), (OR = 0.39, 95%CI 0.19–0.80); but in fully-adjusted model, these relations disappeared. After adjustment for potential cofounders, an inverse association was found between legumes and nuts consumption and odds of hyperglycemia (OR = 0.35, 95%CI 0.16–0.78). Moreover, although inverse significant associations were found between legumes and nuts consumption and odds of MUO in girls and overweight subjects in crude models, these associations disappeared after adjustment for all confounders. After taking potential confounders into account, no significant association was found between consumption of legumes and nuts and MUO in Iranian adolescents. The findings should be affirmed by further prospective studies. https://doi.org/10.1038/s41598-023-32961-2


Comparing the effects of consuming almonds or biscuits on body weight in habitual snackers: A one-year randomized controlled trial

Purpose: Almonds are nutrient-rich, providing a healthier alternative to many snack foods. Studies report health benefits with regular almond consumption without adverse weight gain. However, most interventions have been relatively short or have included additional dietary advice. Taking a pragmatic approach, we compared consumption of almonds versus biscuits on body weight and other health outcomes in a population of regular snackers of discretionary foods, hypothesizing the almonds will displace some of the less healthful snacks in their current diets. Methods: We randomly assigned 136 non-obese habitual discretionary snack consumers to receive almonds or biscuits daily for one-year. These isocaloric snacks provided either 10% of participants’ total energy (TE) requirements or 1030 kJ (equivalent to 42.5 g almonds), whichever was greater. Anthropometry, blood biomarkers, diet, appetite, sleep, and, physical activity, were assessed at baseline, 3, 6, and 12 months, and body composition and resting metabolic rate at baseline and 12 months. Results: The difference in changes for body weight from baseline to 12 months was not statistically significant (geometric means 67.1 kg and 69.5 kg for almonds and 66.3 kg and 66.3 kg for biscuits, P = 0.275). There were no statistically significant differences in changes for body composition or other non-dietary outcomes (all P ≥ 0.112). Absolute intakes of protein; total, polyunsaturated, and monosaturated fat; fibre; vitamin E; calcium; copper; magnesium; phosphorous; and zinc, and % TE from total monounsaturated, and polyunsaturated fat statistically significantly increased from baseline (all P ≤ 0.033), while % TE from carbohydrate and sugar statistically significantly (both P ≤ 0.014) decreased from baseline, in the almond compared to the biscuit group. Conclusions: Almonds can be incorporated into the diets of habitual snackers to improve diet quality, without evidence for changes in body weight, compared to a popular discretionary snack food. https://doi.org/10.1016/j.ajcnut.2023.05.015


Macadamia nut effects on cardiometabolic risk factors: A randomised trial

We sought to examine the effects of daily consumption of macadamia nuts on body weight and composition, plasma lipids and glycaemic parameters in a free-living environment in overweight and obese adults at elevated cardiometabolic risk. Utilising a randomised cross-over design, thirty-five adults with abdominal obesity consumed their usual diet plus macadamia nuts (~15 % of daily calories) for 8 weeks (intervention) and their usual diet without nuts for 8 weeks (control), with a 2-week washout. Body composition was determined by bioelectrical impedance; dietary intake was assessed with 24-h dietary recalls. Consumption of macadamia nuts led to increased total fat and MUFA intake while SFA intake was unaltered. With mixed model regression analysis, no significant changes in mean weight, BMI, waist circumference, percent body fat or glycaemic parameters, and non-significant reductions in plasma total cholesterol of 2⋅1 % (−4⋅3 mg/dl; 95 % CI −14⋅8, 6⋅1) and low-density lipoprotein (LDL-C) of 4 % (−4⋅7 mg/dl; 95 % CI −14⋅3, 4⋅8) were observed. Cholesterol-lowering effects were modified by adiposity: greater lipid lowering occurred in those with overweight v. obesity, and in those with less than the median percent body fat. Daily consumption of macadamia nuts does not lead to gains in weight or body fat under free-living conditions in overweight or obese adults; non-significant cholesterol lowering occurred without altering saturated fat intake of similar magnitude to cholesterol lowering seen with other nuts. https://doi.org/10.1017/jns.2023.39