During a six-week study, overweight and obese participants eating breakfast cereals - such as Nestle's shredded wheat or Fitnesse brand - once a day lost weight after two weeks, that was sustained at six weeks.
"These results confirm that ready-to-eat cereals are an effective short-term weight loss strategy when used as a meal replacement," report the study researchers from Oxford's Brookes University.
The study, sponsored by Cereal Partners UK, the Nestle-General Mills joint venture that claims over 25 per cent of the £1.3 billion UK cereal market, also revealed that subjects who opted for a variety of cereals witnessed enhanced weight-loss over participants eating just a single cereal type.
"Interestingly, significantly greater weight loss was achieved in those subjects randomly assigned to the variety arm [in this case the brands Fitnesse, Shredded Wheat bitesize, and triple berry Shredded Wheat] of the study, compared with a single variety [only Fitnesse]," comment the scientists in a recent issue of the British Nutrition Foundation's periodical, Nutrition Bulletin.
And as a nod to satiety, while the energy and macronutrient content of the cereals were similar, the researchers point out that the dietary fibre content of shredded wheat bitesize, and triple berry shredded wheat was higher than Fitnesse brand.
Such differences in nutrient composition may have played a role in the enhanced weight loss for the 'variety' subjects: "The digestibility of the breakfast cereals and their effects on stomach emptying and satiety may be different," conclude the scientists.
The study design
Fifty-four subjects, 19 males and 35 females aged from 20 to 60 years old and with a body mass index (BMI) between 25 and 35 kg/m2, were randomly allocated to one of two groups, a single cereal group (SC) or a variety cereal group (VC).
For the first two weeks of the study, SC consumed a pre-packaged serving (45 g) of a single brand of ready-to-eat cereal - Fitnesse from Cereal Partners UK with semi-skimmed milk (125 ml) for breakfast and as a replacement meal for lunch.
The VC group freely chose from three pre-packaged serving (45 g) - all made by Cereal Partners UK - of either fitnesse, shredded wheat bitesize or triple berry shredded wheat for breakfast and lunch.
No restrictions were placed on subsequent snack or dinner consumption, and subjects were not asked to alter their eating habits throughout the rest of the day.
For the following four weeks, subjects ate the ready-to-eat cereals for breakfast each day, but ate their regular lunch, dinner and snacks. Throughout the six-week study, both groups received an "accompanying brief guidance" on healthy eating to ensure that subjects "were aware that weight loss could only occur as part of an energy-controlled diet".
"There appears to be an important role for meal replacements as an effective intervention to achieve weight loss, and an increasing body of scientific literature supports this," state the researchers.
Commenting on the mechanism, the researchers noted that the fibre content of the foods may affect feelings of satiety, while meal replacement may be effective for weight loss since it provides a meal in a portion-controlled manner.
Cheap, nutritious (being nutrient but not energy dense), readily available, familiar and palatable, say the scientists, make ready- to-eat breakfast cereals "an attractive meal replacement".
Source: Nutrition BulletinVolume 34, Issue 1, Pages 48-53"An investigation of the effectiveness of ready-to-eat breakfast cereals in weight loss: comparison between single and mixed varieties"Authors: H. J. Lightowler and C. J. K. Henry