Table 6.
Clinical trials investigating the health-promoting properties of almonds.
| Reference | Trial Type | Subjects | Number of Study Participants | Almond Intervention | Duration Intervention | Main Results |
|---|---|---|---|---|---|---|
| Lipidemic control | ||||||
| [57] | R, CO | Normolipemic subjects | 22 | Replacement of 50% of usual daily intake of dietary fat with whole almonds or almond oil | 6 weeks | Significantly reduced serum levels of triglycerides, TC and LDL-c and increased HDL-c |
| [58] | R, CO, C | Subjects with mild hypercholesterolemia | 20 | 20 g almonds daily | 6 weeks | Significantly reduced serum levels of TC, LDL-c and non-HDL-c |
| [59] | R, C | Healthy adults | 85 | 56 g almonds daily | 20 weeks | Significantly reduced TC, LDL-c, non-HDL-c, triglycerides, FM and WHR |
| [60] | R, OL, C | Subjects with hyperlipidemia | 97 | 10 mL almond oil twice daily | 4 weeks | Significantly reduce serum levels of TC and LDL-c |
| Glycemic control | ||||||
| [61] | R, C | Healthy subjects | 15 | Test meal with 60 g almonds | - | Significantly reduced postprandial glycaemia, insulinemia and increased the concentration of serum protein thiol, indicating less oxidative protein damage |
| [62] | R, CO, C | Healthy subjects/T2DM patients | 13/7 | Test meal with 28 g almonds | - | Significantly reduced postprandial glycaemia in the T2DM group |
| T2DM patients | 13 | 1 serving (28 g) of almonds five days a week | 12 weeks | Significantly reduced HbA1c in the T2DM group | ||
| [63] | R, C, PG | Young healthy adults | 73 | 56.7 g almonds daily | 8 weeks | A smaller decline in HDL-c; lower 2-h glucose AUC, IRI and higher Matsuda index during the OGTT, compared to control. Reduced fasting glucose and LDL-c |
| [65] | R, CO, C | T2DM patients with mild hyperlipidemia | 20 | Diet with almonds (20% of energy intake) | 4 weeks | Significantly decreased levels of TC, LDL-c, LDL/HDL ratio, ApoB, ApoB/ApoA1 ratio, non-esterified fatty acid, fasting insulin, fasting glucose and HOMA-IR |
| Obesity | ||||||
| [70] | R, C, PG | Overweight /obese subjects (BMI: 25‒40 kg/m2) | 86 | Hypocaloric, almond-enriched diet (15% energy from almond) | 12 weeks | Greater reduction in truncal, visceral and total fat, diastolic blood pressure |
| [71] | R, CO | Obese adults | 123 | Hypocaloric, almond-enriched diet (28 g daily) | 18 months | Less bodyweight reduction and no significant changes in body composition |
| Cardiovascular risk | ||||||
| [64] | Non-C | Patients with T2DM | 50 | Diet with raw almond (20% of energy intake) | 24 weeks | Significantly improved WC, waist-to-height ratio, TC, triglycerides, LDL-c, HbA1c, hs-CRP |
| [72] | R, CO, C | Subjects with elevated LDL-c | 48 | A cholesterol-lowering diet with 1.5 oz. almond/day | 6 weeks | Significantly reduced non-HDL-c and LDL-c levels accompanied by reduced abdominal and leg fat |
| [73] | R, CO, C | Patients with CAD | 45 | Diet with 85 g almonds daily | 6 weeks | Unchanged vascular outcomes (vascular function, peripheral arterial tonometry, pulse wave velocity), serum parameters (lipid, CRP, TNFα, E-selectin) and blood pressure. Reduced VCAM1 and increased urinary NO. |
| [74] | Non-C | Healthy men mild hyperlipidemia | 30 | 60 g of almonds daily | 4 weeks | Significantly decreased LDL-c, TC and ApoB100 levels |
| [75] | R, CO, C | Hyperlipidemic subjects | 27 | Isoenergetic supplements: full-dose almonds (73 g daily), half-dose almonds+half-dose muffins | 4 weeks | Significantly reduced levels of LDL-c, LDL-c/HDL-c ratio, lipoprotein A and ox-LDL |
| [76] | R, CO, C | Hyperlipidemic subjects | 27 | Isoenergetic supplements: full-dose almonds (73 g daily), half-dose almonds+half-dose muffins | 4 weeks | Increased content of OA and MUFA in TAG and NEFA fractions, which are inversely associated with both Framingham 10-year CHD risk score and CHD lipid risk |
| [77] | R, PG | Adults with prediabetes | 65 | ADA diet containing 20% of energy from almonds | 16 weeks | Significantly reduced levels of insulin, HOMA-IR, HOMA-β, LDL-c |
| Inflammation | ||||||
| [78] | R, CO, C | Healthy adults | 25 | Low-almond diet (10% isoenergetic replacement with almond) and high-almond diet (20% isoenergetic replacement with almonds) | 4 weeks | Significantly reduced levels of E-selectin in high-almond diet and significantly reduced levels of CRP in both diets |
| Oxidative stress | ||||||
| [79] | R, C | Healthy subjects, regular smokers | 30 | 86 g and 164 g almonds daily | 4 weeks | Significantly reduced levels of 8-OH-dG, MDA and single-strand DNA breaks. No significant effects on SOD and GSH-Px. |
| [80] | R, CO, C | Healthy subjects, regular smokers | 60 | 84 g almonds daily | 4 weeks | Significantly increased levels of SOD and GSH-Px and reduced levels of 8-OH-dG, MDA and DNA strand breaks |
| Serum uric acid | ||||||
| [81] | R, C | CAD patients | 150 | 10 g almonds | 12 weeks | Significant reduced uric acid serum levels |
Abbreviations: 8-OH-dG, 8-hydroxy2′-deoxyguanosine; ADA, American Diabetes Association; ApoB100, apolipoprotein B100; AUC, area under the curve; BMI, body mass index; C, controlled; CAD, coronary artery disease; CO, crossover; CRP, C-reactive protein; FM, fat mass; GSH-Px, glutathione peroxidase; HbA1c, glycosylated hemoglobin; HDL-c, high-density lipoprotein cholesterol; HOMA-IR, homeostatic model analysis for insulin resistance; HOMA-β, homeostatic model analysis for beta-cell function; hs-CRP, high-sensitivity C-reactive protein; IRI, insulin resistance index; LDL-c, low-density lipoprotein cholesterol; MDA, malondialdehyde; MUFA, monounsaturated fatty acid; NEFA, non-esterified fatty acid; NO, nitric oxide; non-C; non-controlled; OA, oleic acid; OGTT, oral glucose tolerance test; OL, open-label; oxLDL, oxidized LDL; PG, parallel-group; R, randomized; SOD, superoxide dismutase; T2DM, type 2 diabetes mellitus; TAG, triacylglycerides; TC, total cholesterol; TC, total cholesterol; TNFα, tumor necrosis factor-α; VCAM1, vascular cell adhesion molecule-1; WC, waist circumference; WHR, waist-to-hip ratio.