Effects of consuming a high‐protein diet with or without soy protein during weight loss and maintenance: a non‐inferiority, randomized clinical efficacy trial

Abstract

SummaryObjectiveThis 12‐month randomized, non‐inferiority clinical trial sought to determine the impact of consuming soy protein as part of an energy‐restricted, high‐protein diet on weight loss, body composition and cardiometabolic health.MethodsSeventy‐one adults (58 female) with overweight or obesity (body mass index: 32.9 ± 3.6 kg m−2) were randomly assigned to consume three servings of soy (S) or non‐soy (NS) protein foods per day for 12 months. All participants completed a group‐based behavioural weight loss program lasting 4 months (M4), and follow‐up assessments were completed at month 12 (M12).ResultsBody weight was reduced in both groups at M4 (S: −7.0% ± 5.2%, NS: −7.1% ± 5.7%) and M12 (S: 3.6% ± 5.1%, NS: −4.8% ± 7.3%). Body weight reductions (mean difference [90% confidence interval]) were not different between S and NS at either time point (M4: −0.16% [−1.4, 3.6], P = 0.90; M12: 1.1% [−1.4, 3.6], P = 0.44). Differences in body fat mass loss were not different between S and NS at M4 (0.29 ± 0.84 kg, P = 0.73) or M12 (0.78 ± 1.5 kg, P = 0.59). Weight loss‐induced improvements in cholesterol, triglycerides and blood pressure did not differ between S and NS.ConclusionThese results indicate that soy‐based protein foods can be effectively incorporated into an energy‐restricted, high‐protein diet for improving body weight, body composition and cardiometabolic health.

The health effects of soy: A reference guide for health professionals

“…( 84 ). These findings align with other research, which indicates there is little evidence suggesting one source of protein is more effective than another as an aid for weight management ( 85 – 89 ).…”

A Comprehensive Critical Assessment of Increased Fruit and Vegetable Intake on Weight Loss in Women

“…In 58 obese adults (82% women; mean baseline age 42 years and BMI of 33) consuming energy-restricted low fat and high protein diets including three servings/day of soy protein or non-soy protein foods in a group-based weight loss program for four months showed that soy and non-soy protein had similar effects on body weight and fat loss and maintenance (4–12 months) [ 62 ].…”

Soy Products Ameliorate Obesity-Related Anthropometric Indicators in Overweight or Obese Asian and Non-Menopausal Women: A Meta-Analysis of Randomized Controlled Trials

“…In recent years, the beneficial effect of soy products on body weight has aroused the interest in the scientists [17,18,19], whose biological effects in preventing metabolic disorders such as hyperlipidemia, cardiovascular disease and type 2 diabetes mellitus were commended [20]. Soy products herein refers to soy and a food processed from soy, and is mainly composed of soy protein, soy isoflavone and soy fiber, such as soy milk, soy shakes and so on.…”