Whey and glycemic index

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Hi All,

Whey is a recommended source of protein. How does it affect the glycemic index

of

the meals that include it? The pdf-avaiable not yet in Medline below paper

extracts, suggests " big time " .

Anders H Frid, Mikael Nilsson, Jens Juul Holst, and Inger ME Björck

Effect of whey on blood glucose and insulin responses to composite breakfast and

lunch meals in type 2 diabetic subjects

Am J Clin Nutr 2005 82: 69-75.

.... high glycemic index (GI) ... Fourteen diet-treated subjects with type 2

diabetes

were served a high-GI breakfast (white bread) and subsequent high-GI lunch

(mashed

potatoes with meatballs). The breakfast and lunch meals were supplemented with

whey

on one day; whey was exchanged for lean ham and lactose on another day. Venous

blood

samples were drawn before and during 4 h after breakfast and 3 h after lunch for

the

measurement of blood glucose, serum insulin, glucose-dependent insulinotropic

polypeptide (GIP), and glucagon-like peptide 1 (GLP-1).

Results:The insulin responses were higher after both breakfast (31%) and lunch

(57%)

when whey was included in the meal than when whey was not included. After lunch,

the

blood glucose response was significantly reduced [–21%; 120 min area under the

curve

(AUC)] after whey ingestion. Postprandial GIP responses were higher after whey

ingestion, whereas no differences were found in GLP-1 between the reference and

test

meals.

Conclusions:It can be concluded that the addition of whey to meals with rapidly

digested and absorbed carbohydrates stimulates insulin release and reduces

postprandial blood glucose excursion after a lunch meal consisting of mashed

potatoes and meatballs in type 2 diabetic subjects.

.... TABLE 1 Nutrient composition of the test meal and the reference meal1

.......................................

---- Carbohydrate Protein

----g g

......................................

Reference meal

Breakfast

Bread 44.7 11.6

Ham — 18.2

Lactose 5.3 —

Total 50.0 29.8

Lunch

Mashed potatoes 35.6 3.91

Meatballs 5.01 6.51

Ham — 18.2

Lactose 5.3 —

Total 45.9 28.6

Whey meal

Breakfast

Bread 44.7 11.6

Whey 5.3 18.2

Total 50.0 29.8

Lunch

Mashed potatoes 35.6 3.91

Meatballs 5.01 6.51

Whey 5.3 18.2

Total 45.9 28.6

.......................................

1 According to the manufacturer.

.... TABLE 2 Postprandial areas under the curve (AUCs) for blood glucose, serum

insulin glucose-dependent insulinotropic polypeptide (GIP), and glucagon-like

peptide 1 (GLP-1) after the reference and whey breakfasts, in diet-treated type

2

diabetic subjects1

.....................................

----Reference Whey Change2

.....................................

Glucose AUC (mmol · min/L) %

0–60 min 168±10.23 152±12.9 –9

0–120 min 382±32.0 370±42.8 –3

0–180 min 450±54.2 449±65.8 0

Insulin AUC (nmol · min/L)

0–60 min 7.3±1 12.3±1.74 68

0–120 min 25.5±3.7 33.5±4.34 31

0–180 min 37.5±5.7 44.3±6.14 18

GIP AUC (pmol · min/L)

0–60 min 3231±592 4605±7714 43

0–120 min 7562±1319 9802±15494 30

0–180 min 9565±1631 11464±1746 20

GLP-1 AUC (pmol · min/L)

0–60 min 1356±335 1343±136 –1

0–120 min 2520±507 2598±276 3

0–180 min 2845±563 3088±343 9

...............................................

1 n = 14.

2 Change in postprandial response as a percentage of the reference meal.

3 ±SEM (all such values).

4 Significantly different from reference, P < 0.05 (ANOVA followed by Tukey's

test).

.... TABLE 3 Postprandial areas under the curve (AUCs) for blood glucose, serum

insulin, glucose-dependent insulinotropic polypeptide (GIP), and glucagon-like

peptide 1 (GLP-1) after the reference and whey lunches, in diet-treated type 2

diabetic subjects1

...............................

----Reference Whey Change2

..............................

Glucose AUC (mmol · min/L) %

0–60 min 155±12.33 124±9.54 –20

0–120 min 353±25.6 277±26.84 –21

0–180 min 403±35.0 320±35.54 –21

Insulin AUC (nmol · min/L)

0–60 min 7.3±1.2 11.2±1.14 53

0–120 min 17.0±2.7 26.7±3.14 57

0–180 min 21.5±3.3 32.1±4.24 49

GIP AUC (pmol · min/L)

0–60 min 4323±872 5872±10414 36

0–120 min 9052±1735 12658±24424 40

0–180 min 11692±2239 15656±28894 34

GLP-1 AUC (pmol · min/L)

0–60 min 1752±230 1461±197 –17

0–120 min 3404±429 2907±425 –14

0–180 min 4162±511 3687±593 –11

.....................................

1 n = 14.

2 Change in postprandial response as a percentage of the reference meal.

3 ±SEM (all such values).

4 Significantly different from reference, P < 0.05 (ANOVA followed by Tukey's

test).

Al Pater, PhD; email: old542000@...

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