Cranberries may enhance metabolic and liver benefits of weight loss diet: RCT

02-Jun-2020 - Last updated on 02-Jun-2020 at 15:54 GMT

Adding a cranberry supplement to a weight loss diet program may improve insulin, insulin resistance, and key liver enzyme levels in people with non-alcoholic fatty liver disease (NAFLD), says a new study.

NAFLD is the most prevalent liver abnormality in Western countries and parallels the epidemic of metabolic syndrome, obesity and diabetes. Frequently disabling and occasionally leading to cirrhosis, fatty liver disease currently costs the US health care system about $32 billion annually.

The new double-blind placebo-controlled randomized clinical trial used 288 mg per day of a cranberry extract for 12 weeks, which is equivalent to 26 g of dried cranberry.

“To the best of our knowledge, this is the first randomised clinical trial that has investigated the effect of cranberry consumption on NAFLD characteristics,” wrote the authors in the International Journal of Food Sciences and Nutrition.

“As the most common liver disease, NAFLD is usually associated with underactivity and overnutrition, visceral obesity, insulin resistance, dysglycemia, and dyslipidemia. In managing NAFLD, a dietary change is essential for decreasing body weight, improving metabolic status, and normalising biochemical parameters.

“In this study, we found that co-administering cranberry with a weight loss diet for 12 weeks improves conditions by reducing ALT, insulin, and insulin resistance (HOMA-IR) in patients with NAFLD.”

Study details

Researchers from Ahvaz Jundishapur University of Medical Sciences in Iran recruited 41 people with NAFLD to participate in their study. All participants were assigned to the same weight loss diet, but 20 were given the additional cranberry supplement, while the other 21 received placebo for 12 weeks.

Results showed that both groups experienced improvements in steatosis grade (the amount of fat in the liver) and anthropometric measurements (weight, BMI, body fat, waist circumference, hip circumference, and visceral adiposity index), with no differences between the groups for these measures.

Both groups also displayed reductions in ALT (alanine aminotransferase), a key liver enzyme, but the reductions were significantly greater in cranberry group versus placebo.

Insulin also decreased significantly in both groups, with the cranberry arm of the study again showing greater decreases, compared to placebo.

Both groups also displayed significant improvements in HOMA-IR, a measure of insulin resistance, but the cranberry group experienced significantly greater improvements compared to placebo.

Also, there was an improvement in steatosis grade and anthropometric measurements in both groups (p < .05), and there was no significant difference between the two groups in regard to these factors (p > .05). It seems that 288 mg of cranberry extract might improve managing NAFLD, which is equivalent to 26 g of dried cranberry.

“Many pharmaceutical agents have been investigated specifically for the treatment of fatty liver. However, the beneficial effects of intaking herbal extracts along with complementary medicine in NAFLD patients have received considerable attention in recent years,” wrote the researchers. “The use of this management strategy has many advantages, including minimal side effects and wide application due to worldwide availability and low treatment costs.”

Source: International Journal of Food Sciences and Nutrition
Published online ahead of print, doi: 10.1080/09637486.2020.1746957
“Combined cranberry supplementation and weight loss diet in non-alcoholic fatty liver disease: a double-blind placebo-controlled randomized clinical trial”
Authors: R. Hormoznejad, et al.