J Endocrinol Metab

Journal of Endocrinology and Metabolism, ISSN 1923-2861 print, 1923-287X online, Open Access

Article copyright, the authors; Journal compilation copyright, J Endocrinol Metab and Elmer Press Inc

Journal website http://www.jofem.org

Review

Volume 8, Number 5, October 2018, pages 83-86

Effects of Intake of Soy and Non-Soy Legume on Serum HDL-Cholesterol Levels

**Table 1.** Meta-Analyses Evaluated Effects of Intake of Soy Protein and Isoflavones on HDL-C
Authors	Assessed studies	Subjects studied	Effects on HDL-C	Effects on other lipids and glucose metabolism
CI: confidence interval; HDL-C: high-density lipoprotein-cholesterol; LDL-C: low-density-cholesterol; RCT: randomized controlled trial; TC: total cholesterol; TG: triglyceride.
Tokede et al [16]	RCTs assessing the effects of soy on the lipid profile	35 studies were included. Treatment duration ranged from 4 weeks to 1 year	There was a significant increase in serum HDL-C, 1.40 (95% CI: 0.58 - 2.23) mg/dL	Intake of soy products resulted in a significant reduction in serum LDL-C, -4.83 (95% CI: -7.34 to -2.31) mg/dL, TG, -4.92 (95% CI: -7.79 to -2.04) mg/dL, and TC, -5.33 (95% CI: -8.35 to -2.30) mg/dL
Yang et al [17]	RCTs were included in which soy products supplementation was the only intervention in subjects with type 2 diabetes	Eight studies were included according to the criteria	The intake of soy products was associated with a significant increase in HDL-C (0.05 mmol/L; 95% CI: 0.04 - 0.06)	The intake of soy products was associated with a significant reduction in TC (by 0.42 mmol/L; 95% CI: -0.70 to -0.14), TG (by 0.22 mmol/L; 95% CI: -0.38 to -0.07) and LDL-C (by 0.30 mmol/L; 95% CI: -0.60 to -0.00). There were no significant effects on fasting glucose, insulin and glycated hemoglobin
Anderson et al [18]	RCTs related to soy protein intake and serum lipoprotein changes	Analyses included 20 parallel-design studies and 23 crossover studies	In parallel studies, net serum HDL-C values were 3.2% higher (P < 0.007) with soy versus control	Soy protein intake was associated with net changes in LDL-C values of -0.23 mmol/L (95% CI: -0.28 to -0.18 mmol/L) or a 5.5% reduction in parallel studies and -0.16 mmol/L (95% CI: -0.22 to -0.11 mmol/L) or a reduction of 4.2% with crossover studies (P < 0.001 for parallel versus crossover). In parallel studies, TG values were 10.7% lower (P < 0.008) for soy versus control

Table 1. Meta-Analyses Evaluated Effects of Intake of Soy Protein and Isoflavones on HDL-C

Authors

Assessed studies

Subjects studied

Effects on HDL-C

Effects on other lipids and glucose metabolism

CI: confidence interval; HDL-C: high-density lipoprotein-cholesterol; LDL-C: low-density-cholesterol; RCT: randomized controlled trial; TC: total cholesterol; TG: triglyceride.

Tokede et al [16]

RCTs assessing the effects of soy on the lipid profile

35 studies were included. Treatment duration ranged from 4 weeks to 1 year

There was a significant increase in serum HDL-C, 1.40 (95% CI: 0.58 - 2.23) mg/dL

Intake of soy products resulted in a significant reduction in serum LDL-C, -4.83 (95% CI: -7.34 to -2.31) mg/dL, TG, -4.92 (95% CI: -7.79 to -2.04) mg/dL, and TC, -5.33 (95% CI: -8.35 to -2.30) mg/dL

Yang et al [17]

RCTs were included in which soy products supplementation was the only intervention in subjects with type 2 diabetes

Eight studies were included according to the criteria

The intake of soy products was associated with a significant increase in HDL-C (0.05 mmol/L; 95% CI: 0.04 - 0.06)

The intake of soy products was associated with a significant reduction in TC (by 0.42 mmol/L; 95% CI: -0.70 to -0.14), TG (by 0.22 mmol/L; 95% CI: -0.38 to -0.07) and LDL-C (by 0.30 mmol/L; 95% CI: -0.60 to -0.00). There were no significant effects on fasting glucose, insulin and glycated hemoglobin

Anderson et al [18]

RCTs related to soy protein intake and serum lipoprotein changes

Analyses included 20 parallel-design studies and 23 crossover studies

In parallel studies, net serum HDL-C values were 3.2% higher (P < 0.007) with soy versus control

Soy protein intake was associated with net changes in LDL-C values of -0.23 mmol/L (95% CI: -0.28 to -0.18 mmol/L) or a 5.5% reduction in parallel studies and -0.16 mmol/L (95% CI: -0.22 to -0.11 mmol/L) or a reduction of 4.2% with crossover studies (P < 0.001 for parallel versus crossover). In parallel studies, TG values were 10.7% lower (P < 0.008) for soy versus control

**Table 2.** Meta-Analysis Evaluated Effects of Intake of Non-Soy Legume on HDL-C
Authors	Assessed studies	Subjects studied	Effects on HDL-C	Effects on other lipids
CI: confidence interval; HDL-C: high-density lipoprotein-cholesterol; LDL-C: low-density-cholesterol; RCT: randomized controlled trial; TC: total cholesterol; TG: triglyceride.
Bazzano et al [19]	RCTs which were selected which compared a non-soy legume diet to control, had a minimum duration of 3 weeks, and reported blood lipid changes during intervention and control	10 RCTs	The pooled mean net change in HDL-C was 0.85 mg/dL (95% CI: -1.62 - 3.32, P = 0.05; X² for heterogeneity, P = 0.005)	Pooled mean net change in TC for those treated with a legume diet compared to control was -11.8 mg/dL (95% CI: -16.1 to -7.5); mean net change in LDL-C was -8.0 mg/dL (95% CI: -11.4 to -4.6). Pooled mean net change in TG was -18.94 mg/dL (95% CI: -38.04 - 0.17, P = 0.05; X² for heterogeneity, P < 0.001)

Table 2. Meta-Analysis Evaluated Effects of Intake of Non-Soy Legume on HDL-C

Authors

Assessed studies

Subjects studied

Effects on HDL-C

Effects on other lipids

CI: confidence interval; HDL-C: high-density lipoprotein-cholesterol; LDL-C: low-density-cholesterol; RCT: randomized controlled trial; TC: total cholesterol; TG: triglyceride.

Bazzano et al [19]

RCTs which were selected which compared a non-soy legume diet to control, had a minimum duration of 3 weeks, and reported blood lipid changes during intervention and control

10 RCTs

The pooled mean net change in HDL-C was 0.85 mg/dL (95% CI: -1.62 - 3.32, P = 0.05; X² for heterogeneity, P = 0.005)

Pooled mean net change in TC for those treated with a legume diet compared to control was -11.8 mg/dL (95% CI: -16.1 to -7.5); mean net change in LDL-C was -8.0 mg/dL (95% CI: -11.4 to -4.6). Pooled mean net change in TG was -18.94 mg/dL (95% CI: -38.04 - 0.17, P = 0.05; X² for heterogeneity, P < 0.001)