TABLE 4.
Main findings of the 13 included human studies examining the metabolizable energy or lipid bioaccessibility of tree nuts and peanuts in adults aged 18 y or older
| Reference; country | Fecal excretion | Mean fat and/or energy digestibility (%) or microscopy images | Metabolizable energy (ME) content (mean) |
|---|---|---|---|
| Baer, Gebauer, and Novotny (2012); USA [30] |
CONTROL Fat: 2.0 (SE: 0.8) g/d Energy: 546.8 (SE: 55.6) kJ/d INTERVENTION 42 g/d dose: Fat: 6.7 (SE: 0.8) g/d (P < 0.05 vs. control) Energy: 759.4 (SE: 55.6) kJ/d (P < 0.05 vs. control) 84 g/d dose: Fat: 8.7 (SE: 0.8) g/d (P < 0.05 vs. control) Energy: 923.4 (SE: 55.6) kJ/d (P < 0.05 vs. control and 42 g/d dose) |
CONTROL Fat: 97.3 (SE: 0.7) % Energy: 89.5(SE: 0.4) % INTERVENTION 42 g/d dose: Fat: 92.4 (SE: 0.7) % Energy: 87.4 (SE: 0.4) % (both P < 0.05 vs. control) 84 g/d dose: Fat: 91.5 (SE: 0.7) % Energy: 86.8 (SE: 0.4) % (both P < 0.05 vs. control) |
22.6 kJ/g |
| Baer, Gebauer, and Novotny (2016); USA [31] |
CONTROL Fat: 2.2 (SE: 0.6) g/d Energy: 140 (SE: 8.9) kcal/d (= 586 kJ/d) INTERVENTION Fat: 10.2 (SE: 0.6) g/d Energy: 217 (SE: 8.9) kcal/d (= 908 kJ/d) (both P < 0.05 vs. control) |
CONTROL Fat: 97.0 (SE: 0.6) % Energy: 90.4 (SE: 0.3) % INTERVENTION Fat: 89.0 (SE: 0.6) % Energy: 87.8 (SE: 0.3) % (both P < 0.05 vs. control) |
5.22 (SE: 0.16) kcal/g (= 21.84 kJ/g) |
| Baer and Novotny (2018); USA [32] |
CONTROL Fat: 1.7 (SE: 0.3) g/d Energy: 129.6 (SE: 8.1) kcal/d (= 542 kJ/d) INTERVENTION Fat: 3.6 (SE: 0.3) g/d Energy: 186.3 (SE: 8.1) kcal/d (= 779 kJ/d) (both P < 0.05 vs. control) |
CONTROL Fat: 97.8 (SE: 0.3) % Energy: 94.9 (SE: 0.2) % INTERVENTION Fat: 96.1 (SE: 0.3) % Energy: 92.9 (SE: 0.2) % (both P < 0.05 vs. control) |
137 (SE: 3.4) kcal per 28 g serving (= 573 kJ/28 g) 4.89 kcal/g 2 (= 20.46 kJ/g) |
| Cassady et al. (2009); USA [33] |
INTERVENTION Fat: 10 chews: 4 1g 25 chews: 3 1g (P < 0.05 vs. 10 chews) 40 chews: 29 g (P < 0.05 vs. 10 chews) Energy: 10 chews: 3,901 kJ 25 chews: 3,295 kJ (P > 0.05 vs. 10 chews) 40 chews: 3,103 kJ (P > 0.05 vs. 10 chews) |
Not reported | Not reported |
| Ellis et al. (2004); UK & Canada [34] |
Chewing study: Not reported Digestibility study: CONTROL 2.8 (SE: 1.5) g lipid INTERVENTION 21.4 (SE: 14.4) g lipid (P < 0.05 vs. control) |
Chewing study: Microscopy images show ruptured cells at the at the fractured surface and the free lipid released from cells. Cell walls and oil bodies are still intact in cellular layers underlying the fractured surface (no lipid release). Visible oil droplets on the fractured surface of almond particles. Visible intracellular lipid droplets released from the fractured cell layer. Digestibility study: Microscopy images show intact almond tissue containing intracellular lipids, with some cell walls ruptured, releasing lipid and bacteria located inside cells. Bacterial fermentation eroding cell walls of fractured cells. Bacteria growing on cell wall surface. Fecal bacteria have digested the cell walls and gained access to inside cell. |
Not reported |
| Gebauer et al. (2016); USA [35] Mandalari et al. (2018); USA [49] |
Not reported |
CONTROL Fecal matter contained recognizable remains of plant tissue (comprising food remains, micro-organisms, mucin). No free lipid drops were observed. INTERVENTION Natural: recognizable multicellular particles of almond tissue; few free lipid drops, lipids are confined within cell walls Roasted: recognizable multicellular particles; numerous free lipid drops as well as coalesced lipid present within cells Chopped: appearance of chopped roasted almond tissue; multicellular particles containing coalesced lipid and an abundance of free lipid Butter: smaller multicellular particles of almond tissue; very few lipid drops |
Natural: 4.42 (SE: 0.24) kcal/g (P < 0.05 vs. all other forms) (= 18.49 kJ/g) Roasted: 4.86 (SE: 0.24) kcal/g (P < 0.05 vs. whole natural, almond butter, P > 0.05 vs. chopped) (= 20.33 kJ/g) Chopped: 5.04 (SE: 0.20) kcal/g (P < 0.05 vs. whole natural, almond butter, P > 0.05 vs. roasted) (= 21.09 kJ/g) Butter: 6.53 (SE: 0.19) kcal/g (P < 0.05 vs. all other forms) (= 27.32 kJ/g) Measured ME for natural, whole roasted, and chopped roasted P < 0.05 vs Atwater factors; almond butter P > 0.05 vs. Atwater factors |
| Grassby et al. (2017); UK [47] |
INTERVENTION AF muffins 0-10 h: 1.7 g fat 1 0-24 h: 2.7 g fat 1 AP muffins 0-10 h: 20.9 g fat 1 0-24 h: 29.6 g fat 1 |
INTERVENTION Lipid digested: AF muffins 0-10 h: 96.5% 1 0-24 h: 94.4% 1 AP muffins 0-10 h: 56.5% 1 0-24 h: 38.3% 1 |
Not reported |
| Hollis and Mattes (2007); USA [36] | Not reported | Digestibility coefficient of the diet: CONTROL 96% INTERVENTION 95% (P < 0.05 vs. control) (accounts for ∼84 kJ/d of almond) |
Not reported |
| Levine & Silvis (1980); USA [37] | % Dietary fat excreted per day: INTERVENTION High-fiber diet: Peanuts: 17.8 (SE: 5.3) % Peanut butter: 7.0 (SE: 1.4) % (P < 0.05 vs. peanuts) Peanut oil: 4.5 (SE: 1.4) % (P < 0.05 vs. peanuts and peanut butter) Low-fiber diet: Peanuts: 16.8 (SE: 11.7) % Peanut butter: 4.2 (SE: 1.7) % (P < 0.05 vs. low-fiber peanuts and high-fiber peanut butter) Peanut oil: 1.8 (SE: 0.4) % (P < 0.05 vs. low-fiber peanuts and peanut butter, and high-fiber peanut oil) |
Not reported | Not reported |
| Mandalari et al. (2008); UK [48] | Not reported | After 3.5 h: the nutrients of the cells in the first cellular layer (fractured cells) have been digested. The cell walls and intracellular nutrients are still intact in the underlying cells. After 12 h: release of nutrients underneath the fractured surface (∼3-5 layers), and losses of intracellular contents from intact cells underneath the fractured surface. |
Not reported |
| Nishi et al. (2021); Canada [38] |
CONTROL Fat: 5.9 (SE: 0.9) g/d Energy: 155.4 (SE: 16.1) kcal/d (= 650 kJ/d) INTERVENTION Half-dose: Fat: 10.2 (SE: 0.7) g/d (P < 0.05 vs. control) Energy: 177.7 (SE: 9.6) kcal/d (P > 0.05 vs. control) (= 743 kJ/d) Full-dose: Fat: 12.9 (SE: 1.0) g/d (p<0.05 vs control) Energy: 207.5 (SE: 14.5) kcal/d (P < 0.05 vs. control) (= 868 kJ/d) |
CONTROL Fat: 89.5 (SE: 2.0) % Energy: 92.3 (SE: 0.8) % INTERVENTION Half-dose: Fat: 84.0 (SE: 1.3) % (P < 0.05 vs. control) Energy: 91.0 (SE: 0.5) % (P < 0.05 vs. control) Full-dose: Fat: 83.2 (SE: 1.2) % (P < 0.05 vs. control) Energy: 90.1 (SE: 0.6) % (P < 0.05 vs. control) |
Not reported |
| Novotny, Gebauer, and Baer (2012); USA [39] |
CONTROL Fat: 1.7 (SE: 0.8) g/d Energy: 132.2 (SE: 13.4) kcal/d (= 553 kJ/d) INTERVENTION 42 g/d: Fat: 6.3 (SE: 0.8) g/d (P < 0.05 vs. control) Energy: 217.7 (SE: 13.4) kcal/d (P < 0.05 vs. control) (= 911 kJ/d) 84 g/d: Fat: 10.8 (SE: 0.8) g/d (P < 0.05 vs. control) Energy: 282.3 (SE: 13.4) kcal/d (P < 0.05 vs. control) (= 1,181 kJ/d) |
CONTROL Fat: 97.8 (SE: 0.8) % Energy: 90.5 (SE: 0.5) % INTERVENTION 42g/d: Fat: 93.1 (SE: 0.8) % (P < 0.05 vs. control) Energy: 87.5 (SE: 0.5) % (P < 0.05 vs. control) 84g/d: Fat: 89.9 (SE: 0.8) % (P < 0.05 vs. control) Energy: 85.5 (SE: 0.5) % (P < 0.05 vs. control) |
4.6 (SE: 0.8) kcal/g (= 19.25 kJ/g) |
| Traoret et al. (2008); USA, Ghana, Brazil [40] |
CONTROL Fat: WP: 187.3 (SE: 21.8) kJ/d PB: 220.1 (SE: 35.6) kJ/d PO: 166.3 (SE: 14.4) kJ/d PF: 214.9 (SE: 31.1) kJ/d Energy: WP: 646.5 (SE: 55.2) kJ/d PB: 623.4 (SE: 58.4) kJ/d PO: 626.6 (SE: 36.0) kJ/d PF: 663.6 (63.6) kJ/d INTERVENTION Fat: WP: 271.2 (SE: 22.7) kJ/d PB: 213.8 (SE: 31.3) kJ/d PO: 191.4 (SE: 24.1) kJ/d PF: 189.9 (SE: 25.1) kJ/d Energy: WP: 800.2 (SE: 63.5) kJ/d PB: 703.0 (SE: 74.6) kJ/d PO: 704.7 (SE: 78.0) kJ/d PF: 668.9 (SE: 60.3) kJ/d NS between groups |
Not reported | Not reported |
Abbreviations: AF, almond flour; AP, almond particles; ME, metabolizable energy; NS, PB, peanut butter; PF, peanut flour; PO, peanut oil; not significant; SE, standard error.
1
significance not reported
2
calculated by CJN