Defatted rice intake shown to improve blood pressure and HbA1c levels – 12-week RCT

Defatted rice brand is a byproduct of rice bran oil production. It is rich in non-starch polysaccharides, protein, and antioxidants and used commonly as animal feed.

The trial was conducted by researchers from Chulalongkorn University and findings published in BMC Nutrition. ​

Study design​

Sixty-one overweight or obese individuals with a total cholesterol level of more than 200mg/dL were randomised to take either defatted rice brand or placebo twice per day.

Each day before breakfast and dinner, the intervention group took a sachet containing 15g of defatted rice brand, while the placebo group took a sachet containing 5g of maltodextrin.

Every 30g of defatted rice brand provided 90kcal, 17.78g carbohydrates, 5.55g protein, 7.78g fiber, and zero fat, while every 10g of maltodextrin provided 40kcal and 9.5g carbohydrates. 

The defatted rice brand was provided by Thai Ruam Jai Vegetable Co. Ltd.

Three weeks into the intervention, the participants’ blood pressure, anthropometric parameters, dietary records, blood samples were taken.

Results ​

Both systolic and diastolic blood pressure were significantly reduced in the intervention group by the end of the trial.

For instance, their systolic blood pressure was reduced by 4.27 per cent from 126.20 ± 13.63 to 120.60 ± 13.72 mmHg, while their diastolic blood pressure dropped 4.50 per cent from 80.87 ± 7.38 to 77.17 ± 9.83 mmHg.

No significant changes in blood pressure was seen in the placebo group.

On the other hand, glycated haemoglobin level in the intervention group also decreased significantly by 3.59 per cent from 5.89 ± 0.76 per cent to 5.66 ± 0.62 per cent.

The effect of defatted rice brand was observed as early as week six, the researchers pointed out. 

“There are various possible mechanisms for this improvement, including enhanced secretion of glucose-dependent insulinotropic polypeptide (GIP), reduced appetite and food intake, and inhibition of GLUT 4 transporters. ​

“In addition, it was well established that insoluble fiber may increase fecal bulk and decrease intestinal transit time, thus resulting in decreased absorption of glucose and other simple carbohydrates and an 8 per cent improvement in insulin sensitivity,” ​the researchers explained.

However, the study did not show any significant differences in body weight and other parameters between the two groups, including total cholesterol, triglycerides, and low-density lipoprotein cholesterol levels.

Source: BMC Nutrition​

Effect of defatted rice bran supplementation on metabolic parameters and inflammatory status in overweight/obese adults with hypercholesterolemia: a randomized, placebo-controlled intervention​

DOI: 10.1186/s40795-022-00586-9​

Authors: Weeraya Saphyakhajorn et al​