Welcome
GLYCAEMIC INDEX – A Key Factor In Diabetes
Management
PRESENTED BY
Ms. Mayuri Madhavrao Choudhary
Diabetes Mellitus
• Diabetes – Greek – means “ to siphon ’’.• Mellitus – Latin – means “ sweet like honey ’’.
Excessive water comes out of the body of a person as if it were being siphoned from the mouth through the urinary system out of the body.
Other definitions of Diabetes
• A group of metabolic disorders in which a person has high blood sugar , either because the body does not produce insulin, or what produced is not enough, or because cells do not respond to the insulin as it is not effective.
( Wikipedia )
• A chronic metabolic disorder that prevents the body to utilize glucose completely. ( Srilakshmi,2009 )
• A disorder of carbohydrate metabolism characterized by high blood sugar level ( hyperglycemia ) and high level of sugar in urine ( glycosuria ) . ( Shubhangini Joshi,2005 )
Glucose in blood
Types of diabetes
• Type I ( IDDM ).• Type II ( NIDDM ).• Malnutrition related diabetes
mellitus.• Gestational diabetes.
Prevalence of diabetes
Year 2000 Year 2030
Source : WHO, report 2011 (http://www.who.int/diabetes/facts/world_figures/en/index)
Dietary management in diabetes
S. No. Nutrient Current consensus guidelines
1 Carbohydrates 50-60 % of total energy
2 Proteins 10-15 % of total energy
3 Fats
Total fat < 30 % of total energy
Saturated fatty acids
< 10 %
Trans fatty acids < 1 %
PUFAs 5-8 %
MUFAs 10-15 %
Source : National Consensus Dietary Guidelines For Healthy Living and prevention of obesity, diabetes and related diseases (2009)
Source : Diet and Diabetes – NIN (1993) Nutrition and Dietetics – Shubhangini Joshi (2005) Dietetics – Srilakshmi (2009)
Foods to be avoided and permitted
Foods to be avoided
Foods to be eaten in
moderation
Foods permitted
Simple sugars, syrups, sweets, dried fruits, cake, candy, alcohol and alcoholic beverages, soft drinks, sweetened juices etc.Organ meats like liver , brain , kidney etc.
Fats, cereals, pulses, meat, egg, nuts, roots, fruits etc.
Green leafy vegetables, lemon, clear soups, onion, mint, spices, salad, plain coffee or tea, skimmed and buttermilk etc.
Historical aspects of the dietary management of diabetes
Source : Human nutrition and dietitics (Garrow J.S.2000)
Just in……
In all affairs it’s a healthy thing now and then to hang a question mark on the things you have long taken for granted……
- Bertrand Russell
Glycaemic Index
Definition – The area under the curve for the increase in blood glucose after
the injection of 50 gm of carbohydrate in the food during the 2 hr post prandial period relative to the same amount of carbohydrate from a reference food (i.e.glucose) tested in the same individual under the same conditions and using the initial blood glucose concentration as a baseline.
In simple words, the glycaemic index is a way of ranking carbohydrate containing foods according to the extent to which they raise blood sugar levels after eating.
Formula – Incremental area of the test food
GI = --------------------------------------------- x 100
Incremental area of the glucose
More perfectly…..Example:Example:
Ice-creamIce-creamGI = 39GI = 39 Only 39% of ice-
cream’s carbohydrates turn into blood glucose in the first 2 hours.
The rest will convert to blood glucose over the next several hours.
Method of evaluation of Glycaemic Index
50 g of carbohydrate feeding.
Checking glucose level at regular intervals.
GI calculations by using formula.
Source: Rizkalla et al. (2002) British journal of Nutrition 88, suppl. 3,s255-s262
Glycaemic load
Definition – Glycaemic load is the factor which determines
to what extent eating a food rises the blood sugar level providing a measure of total glycaemic response to a particular food or a meal.
Formula – GL = ∑ (amount of food consumed X
carbohydrate content of food X GI )Given by – Willett et al. (2002)
Factors influencing glycaemic index value
Nature of starch (straight chain, branched chain).
Physical form of the food (liquid, solid, semisolid etc.)
Type of fiber (soluble, insoluble)
Cooking method (boiling, steaming, roasting, baking etc. )
Processing techniques (germination, soaking, fermentation etc.)
Combination of foods (rice and dal, chapati with veg etc.)
Nutrient composition of food (protein content, fat content etc.)
Effect on
because of the nature of starch …
TITLE– Glycaemic index of food: A physiological basis for carbohydrate exchange
Jenkins et al. (1981)
Objective – To determine the effect of different foods on the blood glucose level.
Methodology –
Foods and sugars for testing = 62
Reference food – glucose.
n = 5-10 healthy fasting volunteers.
Calculation of GI.
Table 1 : Glycaemic index of different foodsGrains, Cereal products
GI Dried legumes GI Dairy products GI
Bread (white) 69 Kidney beans 29 Ice-cream 36
Bread (whole meal) 72 Soya beans 15 Milk (skim) 32
Millet 71 Chick peas 36 Milk (whole) 34
Rice (brown) 66 Lentils 29 Miscellaneous GI
Rice (white) 72 Fruits GI Honey 87
Sponge cake 46 Apples 39 Peanuts 13
Breakfast cereals GI Banana 62 Potato crisps 51
All bran 51 Oranges 40 Tomato soup 38
Cornflakes 80 Orange juice 46 Sausages 28
Root Vegetables GI Raisins 64 Fish fingers 38
Beetroot 64 Sugars GI
carrots 92 Fructose 20
Potato 75 Maltose 105
Sweet potato 48 Sucrose 59
Glucose 100
Cont..Results – •No significant relationship between glycaemic index and dietary fiber.
•Low GI of legumes than cereals.
•Fat and protein showed a significant negative correlation with glycaemic index .
•A comparison of glucose, potato, bread, rice, and corn showed that the nature of starch itself may be the factor affecting GI
Conclusion
After this study, they concluded that the classification of foods according to their effects on blood glucose is useful due to the differences in response which exist.
The ability to prescribe a varied diet of low glycaemic index foods for diabetics is especially appropriate at a time when more emphasis is being placed on “ tight’’ blood glucose control in order to avoid long term complications.
TITLE – The glycaemic index of potatoes: the effect of variety, cooking method and maturity
Soh and Brand-Miller (1999)
Objective – To determine the impact of variety,
cooking method and maturity on the glycaemic index of potatoes.
Methodology –
• n = 10
• 8 potato meals (three varieties, four cooking methods, two states of maturity)
• Reference food - white bread.
• Period -10 weeks.
• Capillary blood samples were taken.
• Calculation of GI by using the formula.
Results
No significant difference was found among the three varieties of potato tested (P=0.38) or among the four different cooking methods (P=0.55).
GI was shown to be significantly lowered when a potato was eaten with the skin (69) rather than without the skin (98). Increasing maturity or ripeness of a food also tends to increase GI, and waxy small new potatoes were found to have lower GI values (79 and 80) than floury large old white potatoes (96; not significantly different). This may be because, as the potatoes mature , the extent of amylopectin branching in the starch increases, rendering it more digestible, and thus increasing the GI.
Conclusion
Potatoes, regardless of variety, cooking method and maturity, have exceptionally high GI values. New potatoes have relatively lower GI values which is attributed to differences in starch structure.
Effect on
because of the composition of food…
TITLE – Designing of low glycaemic chapati of dicoccum wheat for the effective management of diabetes
Mundra et al. (2010)
Objectives –1.To analyze the glycaemic index of chapati of dicoccum wheat developed with incorporation of few suitable hypoglycaemic ingredients.
1.To analyze sensory characteristics of the product to judge the suitability for the diabetics.
Methodology –
Dicoccum wheat – Milled to flour Methi seed powder – Overnight soaking followed by drying Whole bengal gram – Soaking→ germinating→ cooking→ drying →flour Bengal gram dal power –Roasting followed by cooking → drying → flour Spice mix – Cumin seeds, fennel seeds, omun seeds (roasting and crusting to a course powder)
Standardization – 4 percent of methi seed powder, 20 percent of cooked bengalgram flour, 4 percent of spice mix.
For glycaemic index – n = 9 healthy Age group – 40-50 years. Reference food – White bread Food for comparison – chapati prepared of only dicocuum flour. Calculation of GI.
The glycaemic index of the designed chapati
Dicoccum wheat products have been found beneficial for the management of diabetes. Enrichment of functional food ingredients like methi seed powder and pulse has brought the enriched chapati under low glycaemic index food successfully.
Effect on
because of the particle size…
TITLE –
Glycaemic responses to cereal-based Indian food preparations in patients with non-insulin-dependent diabetes mellitus and normal subjects
Asna and Shashikala (2000)
Objective –1. To evaluate glycaemic responses to six cereal
based preparations commonly consumed in south India.
Methodology –
Test foods – six conventional cereal based preparations i.e. chapathi, dosai, idali, pongal, poori and upittu with suitable accompaniments.
In vitro study carried out in the laboratory with specific procedure
For in vivo study - No. of subjects
Age group (yrs)
NIDDM 57 42-59
NORMAL HEALTHY
59 22-40
All the selected subjects remained on their usual diets, but fasted overnight before the study.
Reference food - Glucose
Total 6 groups (n= 8-10) received 50 g carbohydrate portions of one of the six foods on seperste mornings.
Table : Mean blood glucose concentration after 30 min in normal and diabetic subjects
Food Mean blood glucose concentration (mmol/l){after 30 min}
NIDDM subjects Normal subjects
Chapati 11.3 + 0.7 5.4 + 0.7
Dosai 13.7 + 1.5 6.6 + 0.5
Idali 10.6 + 2 4.9 + 0.8
Pongal 13.3 + 1 6.2 + 1
Poori 8.3 + 1.1 5.4 + 0.5
Upittu 12 + 0.8 4.9 + 0.6
It is possible to identify food preparations in the habitual Indian diet having attributes of desired glycaemic effect, i.e. delayed peak rise, low glucose response curves.
The finer particle size of dosai and the higher degree of gelatinization attained in pongal probably contributed to increased digestion and absorption of glucose from these foods.
The glycaemic index concept is useful in classifying foods; however the importance of choice of carbohydrate and cooking method should be specified and appropriate dietary guidelines have to be formulated for diabetics.
Conclusion
Cross references for factors
affecting
Cross references Consumption of different carbohydrate foods is found to
elicit different glycaemic response in normal and diabetic subjects (Crapo et al. 1977; Jenkins et al. 1981,1983)
The cooking method and cooking time also determine the extent of starch gelatinization and affect the glycaemic response (Collings et al. 1981).
The slow – release nature of traditional foods is attributed to the presence of pulses contributing the viscous type fiber (Jenkins et al. 1982,1983)
Processing treatments are also known to alter the starch – fiber relationship , increase the accessibility of starch and thus abolish the effect on glycaemia ( Jenkins et al. 1982; Trianedes & O’Dea, 1986)
Cont.... The immediate glycaemic response to a food may be a
predictor of its effect in the long term (Jenkins et al. 1978)
Dietary fiber inhibits starch digestibility by increasing the viscosity of intestinal content and thereby slowing the absorption of carbohydrates from food (Dilwari et al., 1981 and Wolver 1990).
Milling, beating, shearing and refining of foods also affect cell and granule integrity. These processes also decrease particle size and promote absorption of water and breakdown by enzymes. The GI value of such food increases (Foster-Powell and Miller,1995)
Benefits of the
Benefits of GI
• Low GI diet help,1. In dietary management of diabetes. 2. People for weight management.3.To reduce the risk of heart diseases.4. To reduce hunger and enhance satiety.
Low in the weight management.
TITLE –
The effect of altered glycaemic index breakfasts on subsequent food intake and satiety in children aged 9-12 years.
By – Warren et al. 2003
Objective –
1. To study the effect of consuming breakfasts of varying GI on appetite and food intake.
Methodology
n = 38 Subject acted as their own control. 3 diets 3 groups, 3 days each diet (1. Low GI, 2. Low GI with sucrose
added and 3. High GI)
Results
Lunch energy intake was significantly lower after the low GI and the low GI with added sucrose breakfasts compared with after the high GI breakfast or habitual breakfast eaten at home.
No significant difference in satiation (i.e. feelings of fullness ) post breakfast , but satiety rating pre lunch were lower (i.e. hunger was greater) on two of the three experimental days after the high GI breakfast compared with other test breakfasts.
Conclusion Low GI diets may reduce food
intake and have a role to play in weight control and obesity management .
TITLE –
The effect of low and high GI meals on appetite, satiety and energy intake after 6 d low or high GI diet.
By – Norouzy et al. (2003)
Objective –
1. To determine the effect of consuming one low or high GI meal on appetite, energy and micronutrient intake.
Methodology
n = 11 Cross over study. Period of the study – 6 days. VAS (Visual Analogue Scales) was
completed after every 30 min.
Results
Appetite Satiety Fullness feeling
Prospective consumption
LOW GI 1788 2631 2518 2076
HIGH GI 2263 2180 2337 2451
Value in the table are median values for sumed VAS score
Table : median Summed VAS scores
Results Table : Mean nutrient intake
Energy (kcal)
CHO (g)
Fat (g)
Protein (g)
Fibre (g)
LOW GI
2930 324 106 177 46
HIGH GI
3268 338 110 178 47
Significantly lower energy intake during the low GI compared with the high GI period.No significant differences in individual micronutrient intake.
Conclusion Consumption of low GI foods
reduces appetite and increases satiety. This led to a reduction in energy intake but did not ulter the balance between the micronutrients.
The reduction in intake in potentially useful as part of a weight management programme.
Overall conclusion
Glycaemic index is a key factor in diabetes management.
Before prescribing the diet for a diabetic person one should consider the factors affecting the GI value.
Your questions and suggestions are welcomed !
Thank you all for your valuable presence in a Conversation on
……….Glycaemic Index !