Whole grains not only help dieters feel full for longer but could also help people cut down on calories, a new study has revealed.
Those committing to a diet with whole grains, instead of eating refined grains, lost 100 more calories per day.
The research published in the American Journal of Clinical Nutrition found the calorie loss was caused by a reduction in calories retained during digestion, combined with an increase in metabolic rate.
Dietitian Julie Gilbert welcomed the research reinforcing the well-understood benefits of whole grains products including rye bread, brown rice, oatmeal and quinoa.
“There’s been a long-held view that we should cut carbohydrates out of our diet to lose weight, but maybe we do need it in our diets,” Ms Gilbert told The New Daily.
“A lot of people don’t tend to understand that portion sizes are what’s most important. A 70-gram piece of bread, for example, has the same number of kilojoules as half a cup of grains such as rice.
“If you eat too much, you’re still going to gain weight, regardless of whether it’s a whole grain or refined grain product because the calories are the same.
“I’d recommend eating whole grain products like brown rice, basmati, wholemeal pasta and multi-grain. You will feel full after eating less, so it reduces the risk of over-eating.”
While previous studies have shown the benefits of whole grains in providing the impression of “feeling full” for longer from eating less, their impact on weight regulation was yet to be supported.
Ms Gilbert said wider-scale research was still required to review how people may best include whole grains in their daily diet if they were to be used as a weight-loss tool.
“100 calories – the amount lost – is the equivalent to a slice of bread, which is not a lot of weight loss at the end of the day,” she said.
Whole grains and ‘good’ bacteria
Nutritionist Dr Rosemary Stanton said the weight loss benefit findings may be relevant when exploring the role of ‘good’ bacteria in the large intestine, often referred to as the ‘gut micro-biome’.
“Different kinds of dietary fibre promote the growth of these different types of good bacteria,” Dr Stanton said.
“From this study and other work, it appears that we need to eat ‘whole foods’ rather than ‘parts of foods’ to get the full benefit. With many foods containing recombined whole grains, there may be something in ‘intact whole grains’ that goes beyond the benefits of the dietary fibre content.
“We’ve just seen this with studies on turmeric where what was assumed to be the active ingredient doesn’t seem to have any benefits when separated from the food. Also, omega three fatty acids don’t have the same benefits when removed from fish.
“I suspect that with whole grains as well, we may need to consume the whole thing to gain the benefits.”
What makes refined grains different from whole grain
Grains are a major food group that include wheat, rice, oats and barley products.
Whole grains maintain the outer nutritious layer of grains and can be found in products such as whole-wheat flour, oatmeal and brown rice. Refined grains have been processed and broken down into a finer texture, primarily to increase ‘shelf life’.
“This study helps to quantify how whole grains and fibre work to benefit weight management and lends credibility to previously reported associations between increased whole grains and fibre consumption, lower body weight and better health,” lead author Phil J Karl from the Friedman School of Nutrition Science and Policy at Tufts University said.
The Grains and Legume Council in Australia recommends people should aim for a target of 48 grams of whole grains each day.
Originally published at The New Daily.