1) Yogurt has a low glycemic index (GI) of around 27 for plain varieties and 41 for sweetened varieties due to its lactose and protein content. 2) While data is limited, yogurt elicits a lower glycemic and insulin response compared to other snacks like cookies and bananas when consumed. 3) Replacing some high GI foods in meals with yogurt is an effective way to lower the overall dietary GI and potentially reduce risk of type 2 diabetes.

1. Fermented Dairy Intake in Relation
to Glycemic and Insulinemia
Thomas MS Wolever, BA, MA, MSc, PhD, DM (Oxon)
Department of Nutritional Sciences,
University of Toronto, Toronto, ON, Canada.
Keenan Research Centre of
Li Ka Shing Knowledge Institute,
St. Michael's Hospital, Toronto, ON, Canada.
Glycemic Index Laboratories, Inc.
20 Victoria St., Suite 300, Toronto, ON, Canada.
www.gilabs.com

2. Disclosures for
Thomas Wolever
AFFILIATION/FINANCIAL
INTERESTS (past 12 months)
CORPORATE
ORGANIZATION
Grants/Research Support: None
Scientific Advisory Board/Consultant:
Glycemic Index Laboratories,
Inc. (GI Labs), a CRO
Speakers Bureau: None
Stock Shareholder: No Food Companies
Other
GI Labs: my wife and I are
part owners and employees

3. Objectives
• Describe the role of glycemic index (GI) in
reducing risk for type 2 diabetes.
• Review the effect of yogurt on:
– Acute glycemic responses
– Acute insulin responses
• Show how yogurt can be used to reduce
dietary GI.

4. Association of High Yogurt Intake with
Reduced Risk for Type 2 Diabetes
<1/w
k1-4/w
k5-10/w
k>1.5/day
<1/w
k1-4/w
k5-10/w
k>1.5/day
<1/w
k1-4/w
k5-10/w
k>1.5/day
0.4
0.6
0.8
1.0
1.2
Yogurt Yogurt BMI≤25 Yogurt BMI>25
p<0.001p<0.001p<0.001
RelativeRiskofT2DM
Chen M, et al. BMC Medicine 2014;12:215.

5. Why Does Yogurt Reduce Risk for
Type 2 Diabetes?
• Good source of
– Vitamin D (D2d study)
– Calcium
– Conjugated linoleic acid
• Influence on microbiome
• Low glycemic response

6. 1 2 3 4 5 1 2 3 4 5
0.2
0.6
1.0
1.4
Glycemic Index
Glycemic Load
p<0.0001 p=0.02
Quintiles of GI or GL
RelativeRiskofT2DM
Glycemic Index / Load and Risk for
Type 2 Diabetes: 2014
SN Bhupathiraju et al. AJCN 2014;100:218.
49 52 585554
Fully adjusted models: age, race, smoking, hormone/contraceptive use, physical
activity, family history, BMI, and intakes of energy,
alcohol,
coffee, cereal fiber, PUFA, SFA and trans-fat
(and for GI, protein)

7. What is the GI of Yogurt?
www.glycemicindex.com
10≤
>10-15
>15-20
>20-25
>25-30
>30-35
>35-40
>40-45
>45-50
>50-55
>55-60
>60-65
>65-70
>70-75
0
5
10
15
Glycemic Index
Number
n Mean SD Minimum Maximum
93 34.1 13.2 11 67
High GI
(≥70)
Low GI
(≤55)

8. Carbohydrate Content of Yogurts in
GI Database5≤
>5-10
>10-15
>15-20
>20-25
>25-30
>30-35
>35-40
>40-45
>45-50
0
10
20
30
Carbohydrate g/Serving
Number
2≤
>2-4
>4-6
>6-8
>8-10
>10-12
>12-14
>14-16
>16-18
>18-20
>20-22
>22-24
0
10
20
30
Carbohydrate g/100g
Number
Plain
Yogurt
Sweetened
Yogurt
g/100g Skimmed Milk Plain Yogurt Sweetened Yogurt
Carbohydrate 5.2 6.9 14.3
Sugars 5.2 3.4 12.0
Protein 3.6 4.0 3.4
Fat 0 0 0

9. GI of Plain vs Sweetened Yogurt
Plain Yogurts
(n=43)
Sweetened Yogurts
(n=50)
p
Glycemic Index 26.6±10.9 40.5±11.4 <0.0001
Serving Size 192±29 195±31 ns
Carbohydrate (g/serving) 12.4±2.4 30.6±6.3 <0.0001
Glycaemic Load 3.4±1.7 12.6±4.5 <0.0001
Carbohydrate (g/100g) 6.5±1.2 15.6±2.3 <0.0001
GI
Plain Yogurts Sweetened Yogurts
% of CHO GI×%/100 % of CHO GI×%/100
Lactose 48 100% 48 42% 19
Sucrose 61 0% 0 58% 36
Calculated GI of CHO 48 55
10≤
>10-15
>15-20
>20-25
>25-30
>30-35
>35-40
>40-45
>45-50
>50-55
>55-60
>60-65
>65-70
>70-75
0
5
10
15
Glycemic Index
Number
High GI
(≥70)
Low GI
(≤55)
www.glycemicindex.com
+15%
+52%

10. Amount of Protein and Fat
Consumed for GI Testing Yogurt
Portion Size for GI Testing
Plain Yogurt Sweetened Yogurt
Weight (g) 769 321
Carbohydrate 50 50
Protein 29 12
Fat ? 0 - 62 0 - 20
Protein /g CHO 0.58 0.24
Fat /g CHO 0 – 1.2 0 - 0.44
g/100g Skimmed Milk Plain Yogurt Sweetened Yogurt
Carbohydrate 5.2 6.9 14.3
Sugars 5.2 3.4 12.0
Protein 3.6 4.0 3.4
Fat 0 0 0

11. Dose-Response Effect of Fat and
Protein on Glycemic Response
(n=20) 50g Glucose plus:
Corn Oil
Soy Pro
0g 5g 10g 30g
0g 0:0 0:5 0:10 0:30
5g 5:0 5:5 5:10 5:30
10g 10:0 10:5 10:10 10:30
30g 30:0 30:5 30:10 30:30
(n=25) 50g Glucose plus:
Canola Oil
Whey Pro
0g 5g 30g
0g 0:0 0:5 0:30
5g 5:0 5:5 5:30
30g 30:0 30:5 30:30
(n=12) 25g
Glucose +
Whey Protein
0g
4.5g
9g
18g
Moghaddam et al.
J Nutr 2006;136:2506
Lan-Pidhainy & Wolever
AJCN 2010;91:98.
Gunnerud et al.
EJCN 2013;67:749.

12. 0.0 0.2 0.4 0.6 0.8
0
20
40
60
80
100
Moghaddam 2006
Lan-Pidhainy 2010
Fat Intake (g/gCHO)
AUC(Mean±SEM)
(%ofControl)
Small Effect of Fat on Glycemic
Response
Slope -14% per 1g fat/gCHO
GI of Milk
Whole Skimmed
0
10
20
30
40
50
GlycemicIndex
Whole Skim
Mean GI 31.1 34.7
Fat g/gCHO 0.78 0
% reduction 10%
34.7×0.9 = 31.2

13. Effect of Protein Amount and Source
on Glycemic Response
Soy protein:
slope -65% per 1g pro/gCHO
Whey:
slope -76% per 1g pro/gCHO
0.0 0.2 0.4 0.6 0.8
0
20
40
60
80
100
Gunnerud 2013
Moghaddam 2006
Lan-Pidhainy 2010
Protein Intake (g/gCHO)
AUC(Mean±SEM)
(%ofControl)
Plain Sweetened
0
20
40
60
Observed GI±95% CI
Calculated CHO GI
Protein Adjusted
Plain
Yogurt
Sweetened
Yogurt
Protein/g CHO 29/50 = 0.58 12/50 = 0.24
% reduction due
to dairy protein
44% 18% 0.0 0.2 0.4 0.6 0.8
0
10
20
30
40
50
Protein (g/gCHO)
GlycemicIndex

14. Lactic Acid:
Little or no effect on Glycemic Response
0 60 120 180
0
1
2
Bread
Bread & Lactic Acid
(0.28 mmol/g CHO)
Time (min)
∆BloodGlucose(mmol/L)
0 60 120 180
0
1
2
Bread
Bread & Lactic Acid
(0.26 mmol/g CHO)
Time (min)∆BloodGlucose(mmol/L)
HGM Liljeberg et al.
J Nutr 1995;125:1503
HGM Liljeberg & Björck
Am J Clin Nutr 1996;64:886

15. Insulinemic Impact of Dairy Foods
0 40 80 120
0
40
80
120
Glycaemic Index
InsulinaemicIndex
Milk
Yogurt
Lactose
Fermented Milk
148 140
Non-Dairy Dairy
II
GI
Mean±SD 0.97±0.21 3.58±2.0*
(Range) (0.6-1.6) (0.9-6.5)
Pro
CHO
Mean±SD 0.078±0.056 0.66±0.17*
(Range) (0.00-0.19) (0.33-0.81)
Brand-Miller et al.
Brit J Nutr 1995;73:613.
● Non-dairy Foods

16. 0.0 0.2 0.4 0.6 0.8
0
50
100
150
Gunnerud 2013
Lan-Pidhainy 2010
Protein Intake (g/gCHO)
AUC(Mean±SEM)
(%ofControl)Whey Protein and Insulin Response:
Size and Mechanism of Effect
Lan-Pidhainy & Wolever
AJCN 2010;91:98.
Slope = +91% per
1g protein/g CHO
0.0 0.2 0.4 0.6 0.8
0
100
200
300
Protein Intake (g/gCHO)
100×RIR:RGR
Slope = +294% per
1g protein/g CHO

17. Conclusions 1: Glycemic and
insulinemic impact of yogurt
• Yogurt has a low GI:
– Lactose is its available CHO.
• GI of plain/artificially sweetened < sweetened
– Due to higher content of protein per CHO
• Relative to other CHO foods, dairy foods elicit a
disproportionately high insulin response:
– Explained by high protein content
– Not due to increased insulin secretion
– Very few data on insulinemic impact of yogurt (from 1995)
• Low-fat fruit yogurt sweetened with sugar: GI=33, II=28
• Low-fat yogurt aspartame sweetened: GI=14, II=63
• Would this be a problem?

18. Meals with and without dairy
Protein Fat Carb
Bread, butter, orange
juice and beef 31 20 42
Bread, margarine, milk,
yogurt and cheese 31 21 42
Turner et al. Am J Clin Nutr 2016;103:71.
Reported
(netAUC)
My Estimate (incAUC)
Glucose Insulin Glucose Insulin I:G
Beef 0.88 160 68 472 6.98
Dairy 2.33 167 71 496 6.94
0 60 120 180
-0.5
0.0
0.5
1.0
1.5
2.0 Dairy
Meat
Time (min)
∆BloodGlucose(mmol/L)

19. Serving 90g 79g 2 cookies
Kcal 60 70 71
Fat 0 0 2
Avail Carb 12 16 12
Protein 3 1 1
GI 33 53 69
II 57 53 69
2/3
Estimated Glycemic & Insulinemic
Impact of Yogurt vs Other Snacks
??
II/GI increases 294% per gPro/gCHO

20. RGR = 1.64×GI×(1-e-0.0191g
) RIR = II×g/50
Data from: Lee & Wolever EJCN 1998;52:924.

21. 2/3
Estimated Glycemic & Insulinemic
Impact of Yogurt vs Other Snacks
Glucose Insulin
0
5
10
15
20
25
Yogurt Banana Cookies
Relativeto50gGlucose

22. Yogurt to Reduce Diet GI
Sample Menu Yogurt Substituted
Breakfast
Cornflakes and 1%milk Granola and Fruit Yogurt
Toast, Jam, Orange Juice Toast, Butter, Orange Juice
Lunch
PB and Jam Sandwich, Banana PB and Jam Sandwich, Banana
Afternoon snack
Cheese & crackers Vanilla Yogurt and Apple
Dinner
Chicken, Rice and Vegetables Chicken, Rice and Vegetables
Apple Pie and Ice Cream Plain Yogurt and Blueberries
Kcal Protein Fat CHO GI
Sample Menu 1840 74 47 265 64
Yogurt Substituted 1740 75 37 270 56
30-35% risk reduction for T2DM

23. Summary
• Yogurt associated with reduced risk for T2DM
• Low diet GI associated with reduced risk for T2DM
• Yogurt has a low GI
– Due to its lactose and protein content
• Plain/artificially sweetened: 27 (SD=11)
• Sweetened: 41 (SD=11)
• Few data on insulinemic impact of yogurt
– Even assuming a disproportionately high insulin
response, yogurt, whether consumed alone or as a part
of mixed meals, likely elicits similar or lower insulin
response than other meals/snacks
• Yogurt can replace other foods as a healthy way to
reduce diet GI and reduce risk for T2DM.

24. Thank you!

25. DC Greenwood et al. Diabetes Care 2013;36:4166.©2013 by American Diabetes Association
Glycemic Index / Load and Risk for
Type 2 Diabetes: 2013
1.08 (1.02,
1.15)
1.08 (1.02, 1.15)
1.03 (1.00,
1.05)
1.03 (1.00, 1.05)
0.97 (0.90,
1.06)
0.97 (0.90, 1.06)
High
GI
Low
GI

26. Meals with and without dairy
Protein Fat Carb GI
Cereal, milk & fruit 10 3 50 65 S1
Cereal, milk & fruit 11 3 42 35 S2
Bread & vegetable
omelette 18 10 20 66 S3
Bread & vegetable
omelette 17 10 16 40 S4
Cereal, sugar,
milk, banana & OJ 7 2 47 55 S5
Muffin, peanut
butter 5 15 27 56 S6
Wolever et al.
Am J Clin Nutr 2006;83:1306.
0 40 80 120
0
4
8
12
16
20 Dairy
Non-Dairy
Glucose AUC (mmol×min/L)
InsulinAUC(nmol×min/L)
Mean±SD I:G ratio
Dairy: 0.13±0.021
Non-dairy: 0.12±0.014