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Certain foods pack on the pounds
that one consumes — are strongly linked
to weight gain.”
Mozaffarian and his colleagues com-
bined data from three long-term surveys
of middle-aged health professionals in
the United States that were conducted
from 1986 to 2006. The weight, diet and
lifestyle information collected in those
surveys, which included more than
22,000 men and nearly 100,000 women,
enabled the researchers to calculate an
effect for specific foods.
By Nathan Seppa
If there was ever any suggestion that
french fries are good for you, it’s now
dispelled in stark detail. An analysis of
data from three lengthy surveys that
assigns actual pounds of weight gain to
foods finds that fries, sodas and several
other guilty pleasures are among the
most potent waist expanders.
On the bright side, researchers attribute weight loss to eating yogurt, fruits,
nuts and vegetables. The report appears
in the June 23 New England Journal of
Medicine.
Food fright If you are what you eat, then the term “couch potato” is remarkably apt. A study of
more than 120,000 people gauged the effect of adding different foods to the diet. Adding potatoes
and potato products boosted weight; adding fruits, vegetables and nuts to the diet shed pounds.
Effect of adding one serving per day of these foods to a person’s diet
3. 5
“Conventional wisdom often recommends ‘everything in moderation’ with
a focus only on total calories consumed,
rather than the quality of what is consumed,” says study coauthor Dariush
Mozaffarian, a cardiologist at Harvard
Medical School and Brigham and Women’s Hospital in Boston. “Our results
demonstrate that the quality of the
diet — the types of foods and beverages
Weight change per 4 years (pounds)
3.0
2. 5
2.0
1. 5
1.0
0.5
0.0
-0.5
Fruits
Whole
grains
Potato
chips
French
fries
Nuts
- 1.0
SOURCE: D. MOZAFFARIAN ET AL/NEJM 2011
Food types
Vegetables
Sugar-
sweetened
sodas
Unprocessed
red meats
Brain separates
working memory
Hemispheres independent
in mental version of RAM
By Laura Sanders
Like side-by-side computer RAM cards,
the left and the right hemispheres of
the brain store information separately,
a new study in monkeys finds. The
results help explain why people can
remember only a handful of objects at
one time and suggest that it may be possible to maximize mental performance
by delivering information in equal doses
to both sides of the brain, researchers
report in the July 5 Proceedings of the
National Academy of Sciences.
On average, people can hold about
four things in their working memory at
once, such as the location of four cards
in a game of Concentration. Scientists
still don’t completely understand how
the brain reaches this limit.
“Why can’t you think about 100 things
simultaneously, or 50 things simulta-
neously? Why only four?” says study
coauthor Earl Miller of MIT. “If we
understand something about that, we’ll
understand something very deep about
how the brain represents information
and how thoughts are made conscious.”
Miller and his colleagues tested two
monkeys (which also have a four-item
working memory capacity) in a simple
task. First, the monkeys saw two to five
colored squares flash on a computer
screen for less than a second. The
screen went blank, and then the squares
reappeared — but one was a different
color. The monkeys were rewarded for
spotting the change.
