Plant-based, low-fat diet may reduce risk of insulin resistance
A dietary pattern rich in fresh and dried fruits, nuts and seeds, vegetable oils, and low-fat dairy products appears to lower the incidence rate of insulin resistance, according to an Iran study.
“These findings confirmed the protective effect of a plant-based, low-fat dietary pattern against the development of insulin resistance as a main risk factor of type 2 diabetes (T2D) and metabolic disorders,” researchers said.
A total of 802 adults (mean age 39 years; 54.5 percent women) were analysed within the framework of Tehran Lipid and Glucose Study. Extracted were three major dietary patterns (Western, traditional and healthy), which explained 25.3 percent of total variance in food intake.
The healthy dietary pattern, with higher amounts of vegetable oils, fresh and dried fruits, low-fat dairy, as well as nuts and seeds, was associated with a 51-percent lower risk of insulin resistance (odds ratio [OR], 0.49; 95 percent CI, 0.30 to 0.81), and 81 percent in the second and third tertile, respectively (OR, 0.19; 0.10 to 0.36; p=0.001 for trend). [Asia Pac J Clin Nutr 2017;26:531-538]
Logistic regression model showed a 45-percent reduced risk of insulin resistance for every 1-unit increase in healthy dietary pattern score.
“An overview of previous studies revealed relatively similar findings regarding dietary patterns, T2D and metabolic syndrome,” researchers said. “However, limited data are specifically available for insulin resistance indices.”
In one study, prudent dietary pattern score (characterized by higher consumption of vegetables, fruit, fish, poultry and whole grains) correlated with a slightly lower risk of T2D (relative risk [RR], 0.84; 0.70 to 1.00), while the Western pattern score (characterized by higher load of red meat and processed meats, french fries, high-fat dairy products, refined grains, sweets and desserts) increased risk of T2D (RR, 1.59; 1.32 to 1.93). [Ann Intern Med 2002;136:201-9]
A prospective investigation on the link between T2D risk in women and major dietary patterns also showed an elevated risk for diabetes (OR, 1.49; 1.26 to 1.76) in women who had higher scores in the Western pattern. [Arch Intern Med 2004;164:2235-40]
Another study revealed that higher scores in Mediterranean dietary pattern correlated with lower levels of serum glucose and insulin at baseline. A 6-year follow-up showed no significant association between the Mediterranean dietary pattern and the incidence of T2D. [Br J Nutr 2013;109:1490-7]
Adherence to the dietary approaches to stop hypertension (DASH), a diet rich in fruits, vegetables, fibre and low-fat dairy products, also resulted in improved insulin sensitivity. [Curr Hypertens Rep 2011;13:67-73]
“Favourable effects of healthy dietary patterns such as the Mediterranean pattern, DASH diet and the Nordic diet on metabolic disorders have been mainly attributed to higher content of fruits, vegetables, whole grains, dairy and dairy components, calcium, vitamin D, and whey protein, as well as monounsaturated fatty acids, and omega-3 fatty acids,” researchers said. [Nutr Res 2014;34:559-68]
In this longitudinal study, researchers measured fasting serum insulin and glucose at baseline and after a 3-year follow-up. They assessed the usual dietary intakes using a validated 168-item semiquantitative food frequency questionnaire and obtained major dietary patterns using principal component analysis. Logistic regression models were used to estimate the occurrence of insulin resistance across tertiles of dietary patterns, adjusting for potential confounding variables.