Postprandial glycemic responses to a high-protein dairy snack and energy-enriched berry snacks in older adults

Abstract

Background & aims We have previously shown that regular consumption of high-protein dairy- and energy-enriched berry-based products consumed as snacks improved nutritional status, functional status, and quality of life among vulnerable older people. These products contain protein, sugar and other components which may have acute effects on glycemic control. The aim of the present study was to determine the effects of these snack products on postprandial glycemic responses in older adults.

Methods In a randomized, single-blinded crossover design, 25 subjects aged 71.4 ± 4.6 years consumed either a high-protein dairy drink or one of the two energy-enriched berry purées, as well as corresponding reference products, as mid-morning snacks, each containing 25 g of available carbohydrates. Baseline and postprandial blood samples for measurements of glucose, insulin, and non-esterified fatty acids (NEFA) were collected at regular intervals up to 3 h.

Results In comparison with a protein-free reference, consumption of the dairy product resulted in a remarkably high insulin response, a fall in glucose concentration and suppression of late postprandial NEFA rebound. In comparison with a low-berry reference, both berry products led to significantly lower glucose, insulin and NEFA responses.

Conclusions The high-protein dairy product which induces short-term hyperinsulinemia, accompanied with reduced glycemia, may help to improve muscle protein and energy metabolism. The energy-enriched berry products maintain balanced postprandial glycemia. These are beneficial effects in older adults who may suffer from impaired muscle performance or glycemic control.