Table 2.
A summary of dietary intervention studies relating to berry consumption in MetS subjects.
| Berry | Duration | Study Design | Participants/ MetS Classification |
Drug Therapy | Intervention | MetS Findings and Related Parameters | Reference and Country |
|---|---|---|---|---|---|---|---|
| Blueberry | Single dose | Randomized, double-blind, controlled, cross-over | 45 subjects (age: 63 ± 7 y; BMI: 31.4 ± 3.1 kg/m2) MetS classification: Harmonized |
Antihypertensive medication users (38%) or statin users (44%), or a combination | 26 g/day freeze-dried BB (equivalent to 1 cup fresh berries; 150 g) + energy-dense food (900 kcal) Highbush BB (scientific name not reported) Composition: 364 mg ACNs, 879 mg phenolics |
↓ GLC (at time 180 min) ↑↑ HDL-C =SBP, DBP Related parameters: ↓ insulin (at time 180 min), ↓ TC ↑↑ APO-A1, ↑↑ L-HDLP ↑ XL-HDLP |
Curtis et al., 2022 (UK) [32] |
| 6 months | Randomized, double-blind, placebo-controlled, parallel arms | 115 subjects (age: 63 ± 7 y; BMI: 31.2 ± 3.0 kg/m2) MetS classification: Harmonized |
Antihypertensive medication users (24%) or statin users (38%), or a combination | Group 1: 26 g/day freeze-dried BB (equivalent to 1 cup fresh berries; 150 g) Group 2: 13 g/day freeze-dried BB (equivalent to 1/2 cup fresh berries; 75 g) Highbush BB (scientific name not reported) Composition: Group 1: 879 mg phenolics, 364 mg ACNs Group 2: 439 mg phenolics, 182 mg ACNs |
↓ TG =GLC, HDL-C, SBP, DBP Related parameters: =insulin, HbA1c, TC, TC/HDL-C, LDL-C |
Curtis et al., 2019 (UK) [33] |
|
| Single dose | Controlled, crossover | 5 subjects (age: 26–61 y; BMI: 28–40 kg/m2) MetS classification: NCE-ATP III |
No use of statins, anti-diabetics or chronic use of nonsteroidal anti-inflammatory drugs | High fat/high glycemic load meal + 150 g BB BB variety and scientific name not reported Composition: N.A. |
N.A. (other markers are reported in Supplementary Table S1) |
Sobolev et al., 2019 (Italy) [34] |
|
| 6 weeks | Randomized, double-blind, placebo-controlled, parallel arms | 27 subjects (age: 56.5 ± 2.5 y; BMI: 34.7 ± 1.1 kg/m2) MetS classification: WHO |
No use of non-prescription drugs | Twice daily, a 12-oz (∼356 mL) yogurt and a skim-milk-based smoothie with 45 g per day of freeze-dried BB powder (equivalent to approximately 2 cups of fresh berries) Highbush BB Tifblue (Vaccinium ashei) and Rubel (Vaccinium corymbosum) 50/50 Composition: 773.6 mg total phenolics, 290.3 mg ACNs |
N.A. (other markers are reported in Supplementary Table S1) |
Nair et al., 2017 (USA) [5] |
|
| 6 weeks | Randomized, double-blinded, placebo-controlled, parallel arms | 23 subjects (age: 55 ± 2 y; BMI: 35.2 ± 0.8 kg/m2) MetS classification: WHO |
Antihypertensive medication users (95%) | A skim-milk-based smoothie prepared with 45 g BB powder (equivalent to 2 cups of fresh berries) Highbush BB Tifblue (Vaccinium ashei) and Rubel (Vaccinium corymbosum) 50/50 Composition: 773.6 mg total phenolics, 290.3 mg ACNs |
=GLC, TG, HDL-C, SBP, DBP Related parameters: =BW, BMI, % BF, % lean and fat mass, Insulin, TC, LDL-C |
Stull et al., 2015 (USA) [35] |
|
| 8 weeks | Randomized, single-blind, controlled, parallel arms | 48 subjects (age: 50.0 ± 3.0 y; BMI: 37.8 ± 2.3 kg/m2) MetS classification: NCE-ATP III |
Antihypertensive medication users (20%) and multivitamin users | 480 mL/day BB drink (50 g freeze-dried BB corresponding to 350 g fresh berries) Highbush BB Tifblue (Vaccinium ashei) and Rubel (Vaccinium corymbosum) 50/50 Composition: 1624 mg phenolics, 742 mg ACNs |
↓ SBP, DBP =WC, GLC, TG, HDL-C; Related parameters: =BW, BMI, HbA1C, HOMA-IR, TC, LDL-C |
Basu et al., 2010 (USA) [36] |
|
| Bilberry | 8 weeks | Randomized, controlled, parallel arms | 27 subjects (age: 53 ± 6 y; BMI: 31.4 ± 4.7 kg/m2) MetS classification: NCE-ATP III |
No information | 200 g of bilberry purée + 40 g dried bilberries (equivalent to 400 g fresh berries) Vaccinium myrtillus Composition: 1381 mg ACNs, 36.4 mg flavonol |
=WC, TG, HDL-C, SBP, DBP Related parameters: =BW, %BF, TC, LDL-C, Apo-A1, Apo-B, markers of cholesterol synthesis |
Kolehmainen et al., 2012 (Finland) [37] |
| Cranberry | 4 weeks | Controlled, parallel arms | 56 subjects (median age: 50 y; median BMI: 31 kg/m2) MetS classification: NCE-ATP III |
Anti-hypertensive medication users | 700 mL/day reduced-energy cranberry juice Vaccinium macrocarpon Composition: N.A. |
=WC Related parameters: =BMI |
Simao et al., 2013 (Brazil) [38] |
| 4 weeks | Double-blind, placebo-controlled, crossover | 13 subjects § (age: 42 ± 11 y, BMI: 29.3 ± 2.8 kg/m2) MetS classification: NCE-ATP III |
No medications known to affect lipid and insulin metabolism or blood pressure |
500 mL/day of low-calorie cranberry juice (27% juice) Vaccinium macrocarpon Composition: 400 mg total polyphenols, 20.8 mg ACNs |
=SBP, DBP | Ruel et al., 2013 (Canada) [39] |
|
| 8 weeks | Randomized, double-blind, placebo-controlled, parallel arms | 31 subjects (age: 52.0 ± 8.0 y; BMI: 40.0 ± 7.7 kg/m2) MetS classification: NCE-ATP III |
Antihypertensive medication users (20%) and multivitamin users (25%) | 480 mL/day cranberry juice Vaccinium macrocarpon Composition: 229.0 mg total phenolics, 12.4 mg total ACNs, 119 mg proanthocyanidins |
=GLC, TG, HDL-C, SBP, DBP Related parameters: =TC, LDL-C, VLDL-C |
Basu et al., 2011 (USA) [40] |
|
| Raspberry | 12 weeks | Randomized, double-blind, placebo-controlled, parallel arms | 51 subjects (age: 59 ± 10 y, BMI: 25 ± 4 kg/m2) MetS classification: Harmonized |
Aspirin, beta blocker, ACE inhibitor, calcium blocker, diuretics, statin users | 750 mg/day dried unripe black raspberry powder Rubus occidentalis Composition: Reported for the fresh product but not for the powder |
=SBP, DBP | Jeong et al., 2016 (Korea) [41] |
| 12 weeks | Controlled, parallel arms | 77 subjects (age: 60.0 ± 9.4 y; BMI: 25.7 ± 4.2 kg/m2) MetS classification: Harmonized |
Aspirin, beta blocker, ACE inhibitor, statin, users | 750 mg/day of black raspberry powder in capsules Rubus occidentalis Composition: N.A. |
N.A. Related parameters: ↓ TC, TC/HDL-C ratio =Apo-A1, Apo-B, Apo-B/Apo-A1 ratio |
Jeong et al., 2014 (Korea) [42] |
|
| Chokeberry | 4 weeks | Non-randomized, non-controlled | 143 subjects (age: 50–60 y; BMI: 29.7–34.4 kg/m2) MetS classification: AHA/NHLBI |
Statin users | 30 mL/day Standardized chokeberry extract Aronia melanocarpa Composition: 431 mg polyphenols, 120 mg ACNs |
↓ WC, GLC, TG, SBP, DBP =HDL-C Related parameters: ↓ BW, TC, LDL-C =BMI |
Tasic et al., 2021 (Poland) [43] |
| 8 weeks | Non-randomized, non-controlled | 38 subjects (age: 42–65 y; BMI: 31.1 ± 3.3 kg/m2) MetS classification: AHA/NHLBI |
No hypolipemic, hypotensive, anticoagulant, antiplatelet, or profibrinolytic drugs |
300 mg/day chokeberry extract Aronia melanocarpa Composition: 60 mg total polyphenols, 20 mg ACNs |
↓ TG =WC, HDL-C Related parameters: ↓ TC, LDL-C =BMI |
Sikora et al., 2012 (Poland) [44] |
|
| 8 weeks | Non-randomized, non-controlled | 25 subjects (age: 42–65 y and BMI: 31.1 ± 3.2 kg/m2) MetS classification: AHA/NHLBI |
No medication users | 300 mg/day chokeberry extract Aronia melanocarpa Composition: 3-O-cyanidin-galactoside (64.5%), 3-O-cyanidin-arabinoside (28.9%), 3-O-cyanidin-xyloside (4.2%), and 3-O-cyanidin- glucoside (2.4%) |
↓↓↓ TG, SBP ↓↓ DBP ↑↑↑ GLC, HDL-C =WC Related parameters ↓↓↓ TC, LDL-C =BMI |
Broncel et al., 2010 (Poland) [45] |
|
| Strawberry | 8 weeks | Randomized, controlled, parallel arms | 27 subjects (age: 47.0 ± 3.0 y; BMI: 37.5 ± 2.15 kg/m2) MetS classification: NCE-ATP III |
Control group: (24%; antihypertensive medications users) Strawberry group: (0%) |
Four cups daily strawberry drink with 25 g/cup of freeze-dried strawberry powder Strawberry: scientific name not reported Composition: 2 g total phenolics, 154 mg total ACNs |
=WC, GLC, TG, SBP, DBP Related parameters: ↓ small LDL-C particles =BW, lipoprotein particle concentrations and size |
Basu et al., 2010 (USA) [46] |
| Berry mix | 12 weeks | Randomized, controlled, parallel arms | 20 subjects (age: 53.0 ± 6.5 year; BMI: 31.8 ± 4.4 kg/m2) MetS classification: NCE-ATP III |
No information | 300 g/day of fresh berries comprising 100 g of strawberry purée, 100 g of frozen raspberries, and 100 g of frozen cloudberries Berries’ scientific name not reported Composition: 789 mg ellagitannins, 70.7 mg ACNs, 4.1 mg flavonols |
=WC, HDL-C, SBP, DBP Related parameters: =BMI, TC, LDL-C |
Puupponen-Pimiä et al., 2013 (Finland) [47] |
§ subjects with MetS. Legend: The arrow ↑ or ↓ denotes significant increase or decrease, respectively. 1 arrow: significantly different at p < 0.05; 2 arrows: significantly different at p < 0.01; 3 arrows: significantly different at p < 0.001; =: no effect; ACNs: anthocyanins; AHA/NHLBI: American Heart Association/National Heart, Lung, and Blood Institute; APO-A1: apolipoprotein A1; APO-B: apolipoprotein B; BB: blueberry; BF: body fat; BMI: body mass index; BW: body weight; DBP: diastolic blood pressure; GLC: glucose; HbA1c, glycated hemoglobin; HDL-C: high-density lipoprotein-cholesterol; HOMA-IR: Insulin resistance index; N.A.: not available; NCE-ATP III: National Cholesterol Education Program—Adult Treatment Panel III; LDL-C: low-density lipoprotein-cholesterol; L-HDLP: large high-density lipoprotein cholesterol particle number; SBP: systolic blood pressure; TC: total cholesterol; TG: triglycerides; XL-HDLP: extra-large high-density lipoprotein cholesterol particle number; VLDL-C: very low-density lipoprotein; WC: waist circumference. WHO: World Health Organization.