Does adding fiber to a baked good improve the blood sugar response and satiety? Original paper

In this randomized crossover study in adults with no known health conditions, eating a baked good enriched with soluble fiber, compared with the same food without added fiber, resulted in lower postprandial glucose levels and a lower desire to eat.

Whether adding fiber to a baked good influences the postprandial (postmeal) metabolic response or appetite.

The primary outcome was the change in postprandial glucose levels. The secondary outcomes were postprandial insulin levels and the desire to eat, hunger, fullness, and satiety.

10 adults (average age of 36; 6 men, 4 women) with no known health conditions and an average BMI of 23.

In this randomized crossover study, the participants consumed panettone (a sweet bread) either enriched with fiber or not enriched with fiber. The fiber-enriched panettone contained mostly resistant starch and arabinoxylans (a type of soluble fiber extracted from brewer’s spent grain, which is the outer layer of barley kernels).

The meal tests were separated by a washout period of at least 3 days. The participants were instructed to eat a registered dietitian–prescribed standardized diet for 24 hours before each meal test.

Postprandial glucose and insulin levels were assessed before the meal test and for up to 120 minutes after. Appetite was measured before the meal test and up to 240 minutes after, using a visual analog scale. Although not a defined outcome, gastrointestinal symptoms were also assessed with numerical rating scales in the 24 hours following each meal test.

Glucose levels were lower after consuming the fiber-enriched panettone at:

• 90 minutes: 75 mg per deciliter (enriched; mg/dL) vs. 90 mg/dL (unenriched)
• 120 minutes: 72 mg/dL (enriched) vs. 81 mg/dL (unenriched)

Additionally, the overall glucose and insulin levels (i.e., the area under the curve) were lower after consuming the fiber-enriched panettone.

With respect to appetite, after consuming the fiber-enriched panettone, satiety was higher at 240 minutes and the desire to eat was lower at 180 minutes, 240 minutes, and overall than after eating the unenriched panettone.

There were no adverse gastrointestinal symptoms reported.

Because this was a pilot study with a small sample size, the results should be considered exploratory.