Carbs for Breakfast
A new study provides evidence favoring foods with low-glycemic
indexes (GI) such as whole-grain breakfast cereals including
oatmeal, bran cereal, and muesli. It shows that carbs with low
GI's can keep us feeling full and that these foods may have an
important role in weight loss and obesity management.
Diet Study
In the study, children who ate a low-glycemic index meal in the
morning consumed significantly fewer calories at lunch than kids
on a high-GI breakfast. The study is the first to observe such an
effect in a group of normal and overweight children, the
researchers say.
Glycemic Index
The key is the glycemic index - a measure of the effect of foods
on blood sugars. Studies have shown that whole grains and other
foods with low GI's can help keep blood sugar levels stable and
help eaters maintain a feeling of fullness.
Low GI Carbs Reduce Hunger
Carbs with low GI's restrain hunger. In this way, It helps people
lose weight - they simply eat less, writes Janet M. Warren, PhD, a
nutrition and food science writer with Oxford Brookes University
in England. Her study is published in this month's Pediatrics
(11/2003).
Glycemic Index Diet Breakfast Study
Warren and her colleagues tried three types of breakfasts on a
group of students attending a middle school in Oxford. They
monitored how satisfied the children felt after breakfast and how
much each child ate at lunch. Her study involved 37 boys and
girls; 30% of the children were overweight.
The children were divided into five groups. Every week, each group
randomly received one of three test breakfasts for three
consecutive days, in addition to fruit juice.
Breakfast 1
Whole-grain breakfast cereal such as All-Bran, muesli, porridge,
or whole-grain bread (a low-glycemic index breakfast).
Breakfast 2
Whole-grain breakfast cereal or bread, plus sugar for additional
taste (a modified low-glycemic index breakfast).
Breakfast 3
Refined-wheat cereals like Corn Flakes, Coco-Pops, Rice Krispies,
or white bread (a high-glycemic index breakfast).
After breakfast, each child was asked whether they felt full - and
if they liked the way the breakfast tasted. They were instructed
not to eat or drink anything until lunchtime, except water and a
small serving of fruit - an apple, grapes, or an orange.
Effect of Glycemic Index Breakfasts on Lunch Eating Habits
Lunch was a buffet-style meal, and children were allowed free
range to a variety of foods. Unknown to the kids, a researcher
kept track of how much food each child took and how much each ate.
All the children reported being full after breakfast, but they
liked the sugary breakfast cereal best, followed by the low
glycemic index whole-grain-plus-sugar breakfast. The low glycemic
index whole-grain breakfast came up last in likeability.
However, hunger ratings before lunch - and amount eaten at lunch -
were a different matter. The kids who ate the high-glycemic index
breakfast, were hungrier and ate far more than the other groups.
This was true whether the child was overweight or not, boy or
girl.
Result of Diet Study
Bottom line: simple carbohydrates - whether in the form of sugar
or foods made with refined flour- can raise appetite and undermine
the best intended weight loss efforts.
Warren and her colleagues are now conducting further research to
understand the effects of a low-GI breakfast beyond lunchtime. We
don't know what happens for the rest of the day, she says.
It would be premature to recommend eliminating high-GI foods from
the breakfast plate, she says. But the study does highlight the
potential of a low-GI diet amid a growing epidemic of childhood
obesity. |
