Dietary Intake
Table 2 presents dietary data by timepoint. We observed a statistically
significant difference in median calorie intake across all three
timepoints for the entire cohort (P = 0.013); however, by end of
month six, values returned to baseline (P = 0.250). For
macronutrients, carbohydrate intake decreased or stabilized by 6-months
(P = 0.035, P = 0.064, respectively). Additionally, we
observed a corresponding significant increase in protein from study
entry to end of month six (P = 0.027) likely owing to the
underlying tenets of the low-glycemic diet. Despite increases in calorie
intake, we observed a significant reduction in the intake of sugar, a
nutrient strongly associated with weight gain, across all three
timepoints at the end of induction (P = 0.0051) and 6-months
(P = 0.003). We also observed a non-significant increase in
fiber. No difference in median GI was observed throughout the
intervention (P = 0.920); however, a notable change in
energy-adjusted GL was observed (P = 0.030) and there was a trend
towards a sustained reduction in energy-adjusted GL from study entry to
end of month six (P = 0.053).
Several aspects of diet quality improved over the study period
(Supplementary Table #S1). Total vegetable intake increased and
remained elevated at the end of month six compared to intakes at study
entry (P = 0.033). Intake of added sugars decreased by 54.5%
from study entry to end of month six (P = 0.021) and an increased
intake of starchy vegetables excluding white potatoes (P = 0.033)
was observed. Other notable changes in diet quality across the
intervention included increases in total protein foods, total grains,
and oils (P = 0.006, P = 0.004, and P = 0.009,
respectively), though differences were not sustained by the end of month
six (P = 0.130, P = 0.140, and P = 0.280,
respectively).