Inverse association between soya food consumption and insulin resistance in Japanese adults

Abstract

Objective: The purpose of the present study was to examine the association between soya food consumption and insulin resistance using baseline data of the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study in Tokushima, Japan. Design: This cross-sectional study included 1274 subjects, aged 34-70 years at baseline, living in Tokushima Prefecture between 2008 and 2013. Fasting blood samples were collected and information on lifestyle characteristics including soya food intake and medical history were obtained using a structured selfadministered questionnaire. The homeostasis model assessment of insulin resistance (HOMA-IR) was measured and those with HOMA-IR ≥ 2·5 were defined as having insulin resistance. Multiple logistic regression models were used to analyse the association between soya product intake and the prevalence of insulin resistance. Setting: Rural communities located in Tokushima Prefecture, Japan, between 2008 and 2013. Subjects: A total of 1148 adults (565 men and 583 women), aged 34-70 years. Results: The frequency of intake of miso soup, total non-fried soya products and total soya products showed significant inverse dose-response relationships with insulin resistance, after adjustments for potential confounders. When soya product intake was calculated as soya protein and isoflavone, the odds ratios of insulin resistance decreased significantly as the estimated intake of soya protein increased. Furthermore, significant inverse dose-response relationships were observed for total non-fried soya products and total soya products, after adjustment for total vegetable or total fibre consumption. Conclusions: The present results indicate that the intake of soya products and nonfried soya products is associated with reduced insulin resistance in the Japanese population.

Animal-Protein Intake Is Associated with Insulin Resistance in Adventist Health Study 2 (AHS-2) Calibration Substudy Participants: A Cross-Sectional Analysis

“…In a recent cross-sectional analysis from the Nurses' Health Study ( n = 3690), intakes of total, processed, and unprocessed red meat were linked to increased fasting insulin and glycated hemoglobin ( 27 ). In contrast, an inverse association was reported between soy-food consumption and HOMA-IR in a Japanese cohort ( 28 ). To the best of our knowledge, this is the first cross-sectional study to examine the association between intakes of total, animal, and plant protein and the AP intake ratio with insulin resistance assessed by using the HOMA-IR.…”

Nutrient-Derived Dietary Patterns and Their Association With Metabolic Syndrome in a Japanese Population

“… 73 Soy products are also sources of soy protein 74 and isoflavones, 75 which may have a favorable effect on blood glucose, body weight, and fasting insulin. 76 , 77 …”

Inverse association between soy food consumption, especially fermented soy products intake and soy isoflavone, and arterial stiffness in Japanese men

“…Hence, we calculated the intake of soy products per meal from a four, 3-day diet records of 28 participants, in order to estimate soy protein and isoflavone consumption. Correlation coefficients between the estimated consumptions of soy protein and isoflavone from the FFQs and the diet records were 0.47 and 0.59 (Spearman’s rank correlation), respectively 17 . Additionally, the amounts of soy protein and soy isoflavone intakes as well as the total energy intake may be underestimated due to our short FFQ; however, their ranking might be satisfactory.…”

“…Next, we estimated the amount of total soy protein and total soy isoflavone intakes, as previously reported 17 . Since there were no questions on the size of each soy product consumed in the FFQ, 3-day diet records were surveyed four times in approximately 3 months’ intervals (in four seasons in Japan) within one year, in a group of 28 participants.…”