Sustained pectin ingestion delays gastric emptying

Area of Science:

• Gastroenterology
• Human Nutrition
• Dietary Fiber Research

Background:

• Dietary fiber plays a crucial role in regulating gastrointestinal functions.
• Different types of fiber may exert distinct physiological effects.
• Understanding fiber's impact on gastric emptying is vital for digestive health.

Purpose of the Study:

• To investigate the effects of sustained ingestion of apple pectin versus alpha-cellulose on gastric emptying.
• To assess the impact on glucose tolerance, hormone responses, and nutrient absorption.
• To determine if pectin or cellulose supplementation alters key physiological parameters.

Main Methods:

• Healthy volunteers consumed low-fiber diets, followed by isocaloric diets supplemented with either apple pectin or alpha-cellulose for four weeks.
• Gastric emptying was measured using a radiolabeled meal (99mtechnetium sulfur-colloid).
• Plasma glucose, calcium, phosphorus, and various hormones (insulin, glucagon, gastrin, etc.) were quantified.

Main Results:

• Apple pectin supplementation significantly prolonged gastric emptying half-time (p < 0.005), with effects reversing post-supplementation.
• Alpha-cellulose supplementation did not significantly alter gastric emptying rates.
• Neither fiber type affected plasma glucose, calcium, phosphorus, or hormonal responses to a meal.
• Pectin ingestion did not impair jejunal absorption of glucose or lysine.

Conclusions:

• Sustained apple pectin ingestion slows gastric emptying in healthy individuals.
• The mechanism by which pectin affects gastric emptying remains unknown.
• Alpha-cellulose does not appear to have a similar effect on gastric emptying rate.