STUDY AT A GLANCE
THE STUDY:
In an eight-week randomized controlled, parallel-arm invention,
73 healthy college students (41 women, 32 men) consumed either a
snack of dry roasted almonds (56.7 g/day; 320 calories) or graham
crackers (77.5 g/day; 338 calories). Changes were assessed from
fasting serum/plasma samples at baseline and after four and eight
weeks. Acute effects were assessed during a two-hour oral glucose
tolerance test (OGTT) at eight weeks.
RESULTS:
Almond snacking resulted in a smaller decline in HDL cholesterol over
eight weeks (13.5% vs 24.5%, p<0.05), 13% lower two-hour glucose
area under the curve (AUC), 34% lower insulin resistance index (IRI)
and 82% higher Matsuda index (p<0.05) during the OGTT, when
compared with the cracker group. Both groups had similar modest
body mass gains over eight weeks. In general, both almond and
cracker snacking reduced fasting glucose and LDL cholesterol.
STUDY LIMITATIONS:
• The lack of a “no morning snack” group is a limitation that precludes
assessment of breakfast skipping physiological responses. However,
other studies have previously demonstrated the physiological effects
of breakfast skipping among various populations.
6
• Although the body mass gained in both groups was mostly fat-free
mass (0.6 kg), the limitations of bioelectrical impedance analysis in
accurately assessing body composition, particularly in individuals
with obesity, and the limitation of accelerometers in assessing
activity during strength training should be considered while
interpreting this finding.
• Researchers did not conduct the same five-time point OGTT
prior to the intervention, as done at eight weeks for a pre-post
intervention assessment. However, there were no differences in
baseline fasting insulin sensitivity between groups.
• The seven-day spring break that immediately followed the mid-
point of the intervention was a limitation. However, the lack of
remarkable differences at week four that were ultimately captured
at week eight implies that the impact of such an interruption at the
mid-point was not profound.
CONCLUSION:
Incorporating a morning snack in the dietary regimen of predominantly
breakfast-skipping, first-year college students had some beneficial
effects on glucoregulatory and cardiometabolic health. Almond
consumption has the potential to benefit postprandial glucoregulation
in this cohort. These responses may be influenced by cardiometabolic
risk factor status.
• 13% lower two-hour glucose
area under the curve (AUC).
• 34% lower insulin resistance
index (IRI).
• 82% higher Matsuda index
during oral glucose tolerance
testing, which represents a gross
estimation of insulin sensitivity.
This index almost doubled
among the almond snackers.
• Better protection of HDL
(good cholesterol) levels. Both
groups saw reductions in HDL
cholesterol, but the almond
snackers’ levels fell by 13.5%
compared to a 24.5% in graham
cracker snackers.
“This study, the first among a college
student population, shows that for
those who skip breakfast, almonds
are a good snack choice,” says
Rudy Ortiz, PhD, lead researcher of
the study. “For almonds to double
the Matsuda index over an eight-
week period is profound, especially
in a young, healthy population,
illustrating the benefit in insulin
sensitivity that almonds may provide.
And almonds’ effect on several
of the other glucoregulatory and
cardiometabolic health parameters
shows their potential as a smart
snack, particularly in this group.”
Results also showed that both groups
gained a minimal amount of body
mass over the course of the study,
but that’s not surprising. New college
students are prone to modest weight
gain.
8 9
Several studies suggest that
weight gain in college is associated
with a decrease in physical activity.
10
11 12
Despite the minimal increase in
1 7
S E P T E M B E R – O C T O B E R 2 0 1 8
