Berries help to lose bellies
Eating fruit and vegetables that contain high levels of flavonoids could help maintain a healthy weight – according to research from the University of East Anglia (UK) and Harvard University (US).
The study, published today in the BMJ, reveals that apples, pears, berries and peppers were found to have the greatest effect in reducing weight gain.
Researchers from the departments of nutrition at the Harvard TH Chan School of Public Health and UEA’s Norwich Medical School examined the association between the dietary intake of all flavonoids and weight change in a large study of 124,086 men and women based across the US with data collected over 24 years.
Prof Aedin Cassidy, from UEA’s Norwich Medical School, said:
“Dietary flavonoids are natural compounds found in fruits and vegetables. This is the first large study to examine the associations between consumption of all flavonoids and weight gain in middle-aged and older adults.
Most adults gain weight as they age and even small increases in weight can have a substantial impact on risk of high blood pressure, developing heart disease, cancer or diabetes - so strategies to help individuals maintain a healthy weight in middle age are needed.
We found that an increased consumption of most flavonoids were associated with weight maintenance, and even a modest weight loss. The results were found to be consistent across men and women, and different ages.
However losing even small amounts of weight, or preventing weight gain, can improve health and these modest effects were seen with a small, readily achievable increase in intake of many of these fruits.
Just a single portion of some of these fruits per day would have an important impact on health at a population level."
The greatest association was found for anthocyanins – which are found in blueberries, strawberries, cherries, blackberries, grapes, radishes and blackcurrant. We also found that flavonoid polymers – found in tea and apples – were particularly beneficial, along with flavonols – found in tea and onions.
The research team tracked participants who were part of three large prospective cohort studies: the Health Professionals Follow Up Study, Nurses Health Study, and Nurses Health Study II.
Participants self-reported changes in their weight through a questionnaire every two years, between 1986 and 2011. In addition, they self-reported their diet, lifestyle habits, and any recently diagnosed diseases every four years.
The study adjusted for a range of dietary and lifestyle factors that may have influenced the results, such as smoking status and physical activity.
The results show the amount of weight loss associated with very small intakes – called ‘standard deviations’ – including 10mg of anthocyanins and 138mg of polymers.
They found that consuming just a small amount (a standard deviation) of flavonoids correlated with maintaining a healthy weight, and even losing a little – but only around 0.1KG.
However many fruits provide more than one standard deviation increase – for example a single serving per day of blueberries contains up to 121 mg of anthocyanins and tea contains a range of flavonoids (including flavonols, flavan-3-ols and their polymers).
The research team hope that choosing flavonoid-rich fruits and vegetables could help people shed up to one or two pounds.