Eating dried fruit is typically discouraged during weight loss despite evidence that it enhances feelings of fullness. But researchers in the university’s Department of Psychological Sciences sought to examine whether eating prunes as part of a weight loss diet would help or hinder weight control over a 12-week period, and whether prunes induced beneficial changes in appetite.
They found that eating prunes as part of a healthy lifestyle intervention resulted in significant weight loss and waist circumference reduction from the baseline. Not only that, but prunes were well tolerated among participants despite the high daily doses.
The research, funded by the California Prune Board, was presented at the European Congress on Obesity in Bulgaria last week and will be submitted in manuscript format for publication later this year.
For the study, 100 overweight and obese low-fiber consumers (74 women, 26 men; mean age 43 years and mean body mass index of 30kg/m²) were randomly divided into two groups. The intervention group was given prunes (140 g/day for women, 171 g/day for men), whereas the active control panel were given advice on healthy snacks. The prune-eating group experienced mean weight loss of 2.0 kg (4.4 lbs), or 2.4% and waste circumference reduction of 2.5 cm (2.3%) from the baseline. However, the people in the control group lost only 1.5 kg (3.3 lbs) in weight and 1.7 cm from their waists.
The researchers found that weight loss between the groups diverged during the last four weeks, with the prune group experiencing greater weight loss. After week eight, participants in the prune group also showed increased feelings of fullness. Despite the high daily doses (particularly for an otherwise low-fiber group), the prunes were “well tolerated,” according to the study abstract.
“These are the first data to demonstrate both weight loss and no negative side effects when consuming prunes as part of a weight management diet,” psychologist and lead study author Jo Harrold said. “Enduring effects on appetite were also observed with data showing increased fullness in the prune group after week eight. The results may relate to the chronic appetite effects of prunes and dried fruit.”
Mending prunes’ image woes
Despite their beneficial role in overall digestive health, prunes have long suffered from something of an image problem in the US market, where they’re most commonly thought of as a laxative for elderly populations.
But Rachel Cullis Dorsett, European PR manager for the California Prune Board, told FoodNavigator-USA that the results will further turn the tide on public opinion, which she said began last year with the approval of an EU health claim saying prunes contribute to normal bowel function.
“In the case of the satiety results, a program of direct dialogue with health professionals including dieticians will begin the process of setting the record straight about prunes and set the scene to address some of the commonly held negative views about prunes and sugar/weight as well as tolerance and GI side effects,” Cullis Dorsett said. “The work on changing the public perception of prunes began a year ago when in June 2013 California Prunes were awarded an EU health claim which confirms that eating 100g (10 to 12) prunes daily is beneficial to digestive health. This latest piece of research is further proof of their beneficial digestive qualities.”
Source: European Congress on Obesity
“Dried fruit (prune) consumption does not undermine active weight management or produce adverse gastrointestinal effects”
Authors: Harrold J, Hughes G, Boyland EJ, Williams NJ, McGill R, Blundell JE, Finlayson G, Higgs J, Harland J, Halford JC