Glycemic and Insulinemic Response of Staple Indian Foods

Kasturi Sen Ray, Pooja Singhania and Neha PahariaUniversity Dept of Food Science and Nutrition

SNDT Women’s UniversityMumbai,

India

Quality Assessment of Selected Carbohydrate Rich Food for Normal and

Diabetic subjects

In diabetic condition, the metabolism of CHO is completely deranged.-

Dietary management focuses on maintaining the postprandial blood sugar levels close to normal.-

Life long dietary management requires careful selection of the quality and quantity of CHO.

There are food restrictions and taboos controlling the food intake in these subjects.

Many of them are misleading

Glycemic Index (GI) was traditionally used to assess Glycemic Quality of the food on Equi-carbohydrate basis. -

Area under 2 hr bl. Gluc. curve of 50 g CHO from test food Area under 2 hr bl. Gluc. Curve of 50 g glucose in water

GI =

X 100

-Amount of food - providing 50g of available CHO would vary tremendously in different food.

Therefore comparison becomes difficult and impractical.

Watermelon: A high GI of 72, a low GL of only 7.21.

Water melon have 92% water, bread has 37%.

Based on GI, watermelon is not a suitable food for people with diabetes. Bread , not even sweet in taste, have much more starch density and therefore higher glycemic impact.

We do not consume CHO in isolation, rather whole food along with co-nutrients - influencing the glycemic and insulinemic responses of food.

GI cannot reliably predict mixed meal responses.

The quantity of food consumed varies from person to person

GI is an absolute value. So people consume low GI food freely.

To overcome the limitations of GI, Glycemic index food (GIfood) has been introduced. GIfood determines the glycemic impact of

foods on Equi-quantity basis (Monro,

J.A, 2003).

AU 2 hr bl. Gluc. curve after 50 g available CHO from test food AU 2 hr bl. Gluc. curve after 50 g glucose in water

GI =

X 100

Area under 2 hr bl. Glu. response curve after 50 g test food

GI Food = X 100Area under 2 hr bl. Glu. response curve after 50 gm Std. food

GI is based on Food Science point of view

Glycemic index food is a functional classification based on Physiological impact of food

To determine the suitability of food for diabetic subject, we have selected few food items, tested for their physiological impact using GI food

method.

• Rice, • Whole wheat Chapatti • Mango

which are usually modified by the doctors and dietitians for subjects with diabetes.

Rice:

Chapatti:

.

Mango :

Classified as high GI product [GI: 60-110] Commonly restricted for a person with diabetes

Unleavened Indian flat bread made from whole wheat flour, low GI Value (GI = 45.1). Commonly advised and favorably consumed by Indians for its higher nutrient density

Strictly restricted for a person with diabetes due to its high free sugar content. Average GI of 51. An excellent source of soluble fibre, antioxidants like vitamin C and A and Beta carotene, a good source of vitamin B6 and other Phytonutirents of immense health benefits.

Materials and Method

Inclusion criterion of the subject:

The maturity onset diabetic subject [n=8,]

Age group of 45- 65yrs,Without any co-morbidity, Blood HbA1c level < 8, Comparatively stable sugar level with

hypoglycemic medicine ,

Age and BMI matched clinically healthy adults as normal group [n = 6]

Study design:

Blood was collected in fasting state and at 30, 60, 90 and 120 min post consumption of foods (Standard and test) with 100ml water, on different occasions.

Blood glucose and insulin was assessed following the double blind system.

Starch and moisture content of the food were analyzed.

The Incremental Area Under the Curve (IAUC) of Glycemic and Insulinemic response for each food sample was calculated.

•Result and discussion  

- Proximate Composition of standard and test food

Food Product

Starchwwb g %

Total sol. Sugars

(g%)

Total CHO (g %)

Protein(g %)

Fat(g %)

Moisture(g %)

W. Bread(Britannia)

33.97±0.7

3.94 41.68 8.31 1.71

±0.9

37.26±3

Boiled Rice

(Surti Kolam)

20.47±0.4

- 20.47 7.33±0.6

1.35±0.9

75.15±1

Chapatti (whole wheat)

39.34±3.5

- 39.34 10.35±1.0

2.5 ± 1.0

27.16±5

MangoVariety:

Alphanso

3.45 ±5 .2

20 23.83 1.01 - 74.09

Fas 30m 60m 90m 120m

5.0

6.0

7.0

8.0

9.0

10.0

11.0

12.0

13.0

14.0

Bread Rice Chapati Mean

+ S

E B

lood

Glu

cose

mm

ol/

L

Diabetic

Fas 30m 60m 90m 120m 5.0 6.0 7.0 8.0 9.0

10.0 11.0 12.0 13.0 14.0 15.0

Bread Rice Chapati

Mea

n +

SE

Blo

od

G

luco

se

mm

ol/

L

Average delta glycemic impact of rice and wheat chapatti

(n = 8/group)

Normal

Diabetic : Cmax for rice was achieved by 30m followed by gradual decline to baseline. Equi-quantity Chapatti and bread cmax at 60m and continue to stay elevated even at the end of 120 min.

Normal: Bl. Glucose for all the product came down below baseline within 120m.

Fas 30m 60m 90m 120m -

2

4

6

8

10

12

14

16

18

20

Bread Rice Chapati

Mean

+ S

E S

eru

m

Insu

lin

mU

/L

Diabetic

Fas 30m 60m 90m 120m -

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

Bread Rice Chapati

Mean

+ S

E S

eru

m I

nsu

lin

m

U/L

Normal

Relative Insulinemic Impact of rice and Wheat chapatti

• Foods which trigger lower insulin secretion will be beneficial in diabetic condition . The insulin response to rice is lowest

followed by chapatti and bread.

Dose Response

The quantity of food consumed per meal varies from person to person ,affecting the blood glucose and insulin levels.

When the quantity changes, the GI Value does not change although it may result hyperglycemic effect.

GIfood Value is dose sensitive as well.

Average IAUC of Rice and Chapatti individuals

Rice 50g Rice 100g Chapatti 50g Chapatti 100g

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

3743

6838

5330

8916

7301244 1273 1692

Glycemic IAUC Insulin IAUC

Rice 50g Rice 100g Chapatti 50g

Chapatti 100g

0

1000

2000

3000

4000

5000

6000

7000

8000

1965

3990

2690

4230

2200

5647

2772

7563

Glycemic IAUCInsulin IAUC

NormalDiabetic

o Diabetic: When dose is increased, insulin is not increasing proportionately and therefore blood glucose is increasing more.

o Normal: The glycemic response to wheat chapatti is only 6% higher than rice, however, the insulin response for the same is 34% higher than rice.

o It indicate the higher insulinemic impact of wheat starch in comparison with rice starch.

GIfood is expressed in terms of Glycemic Bread Equivalent

[GBE]

GBE is “weight of bread that would induce the same glycemic response as a given amount of test food”.

Glycemic Bread Equivalent works like currency

Common serving sizes Food 50g/HH

measure

50g/GBE HH measure /

Serving

Amount (g)

/ Serving

GBE

/serving

Bread 3 ¼ slices 50 2 slices 31 31

Wheat

Chapatti

1½ medium 44 2 medium 60 73

Rice 1/4 cup 11 1 cup 130 26

(Sen Ray & Singhania (2015)

High moisture containing foods e.g. boiled rice (1 cup) can be safely consumed in their regular serving size without posing risk of postprandial hyperglycemia.

whereas, the normal serving size of Chapatti (2 medium) may produce prolonged hyperglycemia even greater than that induced by same amounts of bread

GBE of rice is 20means that 100g rice produces same glycemic responses as 20g bread

Even within a particular food group (cereals) Glycemic and insulin response varies a lot in both diabetic and normal individuals.

 

Fas 30m 60m 90m 120m

5.0

6.0

7.0

8.0

9.0

10.0

11.0

12.0

13.0

14.0

Bread Mango

Me

an

+ S

E B

loo

d G

luco

se

m

mo

l/L

Dia-betic

Fas 30m 60m 90m 120m 5.0

6.0

7.0

8.0

9.0

10.0

11.0

12.0

13.0

14.0

15.0

Bread Mango

Me

an

+ S

E B

loo

d

Glu

co

se

mm

ol/

L

Normal

Mango exerts a lower glycemic response than white bread in terms of both Cmax as well as AUC in diabetic and normal individuals .

The IAUC of mango was seen to be 3 times lower than standard food bread, in both the groups and this difference is significant.

Glycemic Impact of Mango

Mango FruitsSugars naturally present in food have a lower

glycemic impact than refined starchy carbohydrate foods, e.g. Bread [Wolever and Brand Miller, 1995].

Fruits mainly contain simple sugars such as sucrose, glucose and fructose

In fruits, the starch present in form of resistant starch RS1 or RS2 as intact encapsulated and not available to the digestive enzymes.

RS3 is found in only cooked food items and absent in fresh fruits.

Conclusion Wheat products – Wheat Chapatti and

bread, not sweet in taste, having higher glycemic impact and high demand for insulin, may not be a preferred choice for Diabetic person.

Rice , commonly restricted in diabetic individuals due to its high glycemic index- is a better option as a carbohydrate source for diabetic person.

The lower insulinemic impact of rice may help in reducing the stress on the pancreas, particularly beneficial in management of diabetes and people with insulin resistance.

GBE can be used to predict response to common serving / any measures consumed.

Having same unit in gm, can be included in the Food Exchange table

Thank you