Intake of various types of lettuce, like red oak, butterhead, and cos, could help prevent increases in blood glucose and cholesterol levels, according to a study published in the journal Recent Patents on Food, Nutrition & Agriculture. According to recent research, natural dietary fiber from salad vegetables can reduce glucose and lipid absorption and breakdown rates, thus preventing increases in postprandial blood sugar and cholesterol levels.

Prevention of spikes in blood sugar right after eating a meal is an important therapeutic target. It helps optimize blood sugar control and mitigates damage to our arteries, thereby decreasing the long-term risk of severe complications like heart attacks and strokes.

For the study, fiber was prepared from each type of lettuce using an enzymatic method and then characterized. Physical properties, including solubility and water-binding, swelling, cation-exchange, and oil-binding capacities, and antihyperglycemic and antihypercholesterolemic effects of fiber, were investigated. The results showed that:

a. The hydration capacity of total dietary fiber and insoluble fiber from most sources was significantly different from cellulose.
b. Adsorption and diffusion of glucose were directly proportional to incubation time, and the diffusion rate was considerably lower in the treatments containing fiber than the cellulose control.
c. Fiber from these vegetables also inhibited amylase and alpha-glucosidase activities.
d. Moreover, fiber from all sources exhibited significantly higher sodium cholate and cholesterol-binding capacity than cellulose and retarded pancreatic cholesterol esterase activity in a concentration-dependent manner.

Therefore, the authors concluded that “natural dietary fiber from salad vegetables can reduce glucose and lipid absorption and breakdown rates, thus preventing increases in postprandial blood sugar and cholesterol levels, which can be beneficial to human health.”

Recent Patents on Food, Nutrition & Agriculture