Changes in body weight in response to pecan-enriched diets with and without substitution instructions: a randomised, controlled trial

Abstract

Substantial evidence suggests that regular tree nut consumption does not lead to changes in body weight (BW). However, these studies used a variety of dietary substitution instructions which may confound the interpretation of prior BW outcomes. The purpose of the present study was to examine the impact of daily pecan consumption, with or without isocaloric substitution instructions, on BW and composition. This was an 8-week randomised, controlled trial with three treatments: a nut-free control group (n 32) and two pecan groups. ADD (n 30) consumed pecans (68 g/d) as part of a free-living diet, and SUB (n 31) substituted the pecans (68 g/d) for isocaloric foods from their habitual diet. BW and total body fat percentage (BF) were measured, and theoretical changes in these outcomes if pecans were consumed without compensation were determined. BW increased in all groups across the intervention, and there was a trend (P = 0⋅09) for an increase in ADD (1⋅1 ± 0⋅2 kg) and SUB (0⋅9 ± 0⋅3 kg) compared to control (0⋅3 ± 0⋅2 kg). In addition, there was increased BF in SUB (1⋅0 ± 0⋅3 %; P = 0⋅005) but not ADD (0⋅1 ± 0⋅2 %) or control (−0⋅2 ± 0⋅3 %) There was a large difference in the actual v. theoretical change in BW regardless of pecan treatment (actual: 1⋅1 ± 0⋅2 and 0⋅9 ± 0⋅3 v. theoretical: 3⋅3 ± 0⋅0 and 3⋅2 ± 0⋅0 kg in ADD and SUB, respectively; P < 0⋅001). Furthermore, there was a difference in actual v. theoretical change in BF in ADD (0⋅1 ± 0⋅2 v. 1⋅2 ± 0⋅1 %; P = 0⋅002) but not SUB or control. In conclusion, daily pecan consumption for 8 weeks did not result in significant weight gain, regardless of dietary substitution instructions.

Association of Tree Nut Consumption with Cardiovascular Disease and Cardiometabolic Risk Factors and Health Outcomes in US Adults: NHANES 2011–2018

“…A recommended nut consumption for cardiovascular prevention is 1.5 ounces per day (∼42.5 g) [ [47] , [48] , [49] ]. A concern about tree nuts is that they are high in energy and total fat, [ 50 ] yet clinical trials have demonstrated that not all energy present in tree nuts is bioavailable [ [51] , [52] , [53] , [54] , [55] ]. Moreover, a systematic review and meta-analysis of prospective cohorts and randomized controlled trials demonstrate that nut consumption does not lead to increased weight or measures of adiposity [ 56 ].…”

A Slight Adjustment of the Nutri-Score Nutrient Profiling System Could Help to Better Reflect the European Dietary Guidelines Regarding Nuts

“…Several reasons for the absence of weight gain ensuing nut consumption have been considered. First, eating nuts increases satiety due to their high fat and fibre contents, with the suppression of hunger and promotion of fullness [1,9,45]. Second, nut ingestion entails impaired energy absorption efficiency in the gastrointestinal tract due to a reduced bioaccessibility of fat encased in nut cell walls, plus an increased binding of fatty acids in the gut by nut fibre, with attending increases in fecal fat losses [1,9].…”