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Glycemic Indices and Glycemic Load of Some Nigerian Foods

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The concept of glycemic index (GI) lists food items by virtue of their influence on postprandial glucose. Though the glycemic index of common food items has been determined, the GI of the popularly processed and commonly consumed foods in Nigeria is not known. This study determined the GI of ten processed Nigerian foods and revealed their similarity in the release of glucose on consumption. The food items tested were made from yam tubers, cassava tubers and local cereals. These foods were served to human volunteers in several processed forms which resulted in viscous pastes. The GI results are presented and it is recommended that these processed foods should be discouraged in the regular dietary plan of people with chronic diseases such as coronary heart diseases, diabetes and cancer.
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Pakistan Journal of Nutrition 7 (5): 710-716, 2008
ISSN 1680-5194
© Asian Network for Scientific Information, 2008
710
Glycemic Indices and Glycemic Load of Some Nigerian Foods
E.S. Omoregie and A.U. Osagie
Department of Biochemistry, Faculty of Life Sciences, University of Benin, P.M.B. 1154, Benin City, Nigeria
Abstract: The concept of glycemic index (GI) lists food items by virtue of their influence on postprandial
glucose. Though the glycemic index of common food items has been determined, the GI of the popularly
processed and commonly consumed foods in Nigeria is not known. This study determined the GI of ten
processed Nigerian foods and revealed their similarity in the release of glucose on consumption. The food
items tested were made from yam tubers, cassava tubers and local cereals. These foods were served to
human volunteers in several processed forms which resulted in viscous pastes. The GI results are
presented and it is recommended that these processed foods should be discouraged in the regular dietary
plan of people with chronic diseases such as coronary heart diseases, diabetes and cancer.
Key words: Glycemic index, postprandial glucose, processed Nigerian foods, diabetes mellitus and pastes
Introduction
The concept of glycemic index (GI) was proposed by
Jenkins and colleagues to characterize the rate of
carbohydrate absorption after a meal (Jenkins et al.,
1981). GI is defined as the area under the glucose
response curve after consumption of 50g carbohydrate
from a test food divided by the area under the curve after
consumption of 50g carbohydrate from a control food,
either white bread or glucose. (Wolever et al., 1991).
Over the past three decades, the GI of over 800 foods
has been determined worldwide and more foods are
being tested on weekly basis. The latest update in 2005
has 1300 entries derived from published and
unpublished verified sources (Foster-Powell et al.,Materials and Methods
2002). However, only limited information is available on
African traditional foods. Many factors together, including
carbohydrate type, fiber, protein, fat, food form and
method of preparation, determine the GI of a particular
food (Bjorck et al., 1994, Welch et al., 1987, Wolever et
al., 1991). High GI foods elicit, calorie for calorie, higher
insulin levels and c-peptide excretion than low GI foods
(Haber et al., 1997; Jenkins et al., 1987; Wolever and
Bolognesi, 1996). The reductions in dietary GI may also
lower the risks for various conditions associated with
hyperinsulinemia, such as diabetes mellitus (Salmeron
et al., 1997) and cardiovascular disease.
There is need for more research into the GI of our locally
consumed foods in order to produce data that can
effectively enable use of GI along with other dietary
recommendations in the treatment, management and
prevention of diseases. There are many proven benefits
of using the GI in nutrition. These include: (i) decreased
risk of cardiovascular disease; (ii) better diabetes
management and (iii) more successful body weight
management. Inspired in part by a hope to learn to
predict better, the GI of variants of foods of known GI
value, several groups have studied associations
between GI and defined components in groups of foods
(Jenkins et al., 1981; Wolever, 1990; Hollenbeck and
Coulston, 1991; Nishimune et al., 1991). Apparently, GI
values reflect, mainly, how promptly and rapidly glucose
enters the blood after food ingestion. In Nigeria, the adult
population eats foods made from yam tubers (Dioscorea
spp.), plantain (Musa spp.), cassava (Manihot spp.) and
locally grown cereals. The dry powdered forms of these
plant storage organs are reconstituted in hot water to
form solid pastes which are swallowed with soup. The
effects of processing these food items into diet pastes
on the GI have not been determined.
Experimental design: Fifty healthy human beings were
offered in a single meal, one of the ten food samples.
Blood samples were collected before feeding and
during the 180 min after the meal. Blood glucose was
determined. The integrated areas under the
postprandial glucose response curves were calculated.
Subjects: Fifty subjects aged between 16 and 40 years
(23 male and 27 female) were selected from students
and staff of the University of Benin, Benin City, Nigeria.
They were clinically normal, non-smokers and non-
diabetic. The subjects were appraised verbally and they
gave their informed consent.
Preparation of experimental diets: The dry powdered
food samples were purchased from Edaiken Market in
Benin City, Nigeria. The food samples were powdered
maize, rice, millet, wheat, sorghum, yam and cassava.
These were each sieved to pass through a 100-mesh
filter and then reconstituted into solid pastes in hot water
by a trained cook to ensure consistency (Table 1). The
pastes obtained were as follows:
Omoregie and Osagie: Glycemic indices and glycemic load of some foods
711
Table 1: Processing and Preparation of the Diet Pastes (Okoh, 1998)
Agricultural Form Pre-Processing Paste Preparation
1. Cassava tuber (Manihot utilisima): Eba/Garri Tuber was homogenized in water. Dry powdered starch was
Cassava Starch The starch was allowed to settle, reconstituted in hot water with addi-
filtered out and dried at 28 C. tion of small quantity of palm oil.
o
2. Cassava tuber (Manihot utilisima): Tuber was grated and dried then Dry powder was added to boiling
fried in shallow heated pots. water to form a paste.
3. Yam tuber (Dioscorea rotundata): Fresh tuber was sliced into thin pieces. Dry powder was added to boiling water
Amala and sun-dried for 7 days. Dried slices and stirred until a solid paste was .
were milled to powder obtained
4. Maize (Zea mays): Agidi The dry grains were soaked in water Dry powder was added to boiling water
and fermented for about 3 days. and stirred until a semi-solid paste
The fermented grains were milled resulted. Paste hardened further on
and sieved to remove pericarp and cooling.
bran fractions. The starch fraction
was dried slowly.
5. Maize seeds (Zea mays): Clean, dry grains were moistened with Dry powder was added to boiling
Tuwo Masara water and milled. The hulls were rem- water and stirred until a solid paste
oved by aspiration while the endosperm resulted.
and germs were removed by passing
through a sieve leaving the maize grits.
6. Millet grains (Pennisetum The grain was pounded in a wooden Dry flour was added to boiling water
typhoides): Tuwo Gero mortar. The bran was winnowed off. and stirred until a solid paste resulted
The separated grain was then pounded
into flour.
7. Sorghum seeds (Sorghum The moist grain was pounded with a Dry flour was added to boiling water and
bicolor L. Moench): Tuwo Dawa wooden pestle in a mortar until most stirred until a solid paste was obtained.
of the pericarp was removed. The bran
fraction was removed by winnowing.
The dehulled grain was again pounded
to make flour.
8. Rice (Oryza sativa): Tuwo Shinkafa Polished rice was pounded and Dry flour was added to boiling water and
fltered through a sieve. stirred until a solid paste was obtained.
9. Wheat (Triticum aestivum): Semovita Wheat grains were cleaned, conditioned Flour was added to boiling water and stirred
and milled into flour. until thick and consistent paste cooked for
additional 1-2 minutes.
10. Wheat (Triticum aestivum): Semolina Wheat grains were cleaned, conditioned Flour was added to boiling water and stirred
and milled into flour. until thick and consistent paste was obtained.
Paste was cooked for additional 1-2 minutes.
1. Cassava: Starch Determination of blood glucose: All subjects for the
2. Cassava: Eba Garri
3. Yam: Amala
4. Maize: Agidi
5. Maize: Tuwo Masara
6. Millet: Tuwo Gero
7. Sorghum: Tuwo Dawa
8. Rice: Tuwo Shinkafa
9. Wheat: Semovita
10. Wheat: Semolina
Preliminary trials were carried out using local foods
prepared in a similar manner from plantain (elubo), yam
(pounded yam), cassava (lafun) and fermented cassava
(akpu). The processed pastes were analyzed for
proximate composition of moisture, ash, crude fat, crude
fibre and protein (AOAC, 1983). Carbohydrate was
determined by difference. 50g of available carbohydrate
for each test food sample was calculated from the
results of the proximate analysis and the measured
portion of the food was served to the subjects.
investigation fasted overnight. Their blood samples were
collected through finger prick using a hypodermic needle
or lancets. Each blood sample was placed on a test
strip which was inserted into a calibrated glucometer.
(Accu-Check/One touch) which gave direct readings after
45 seconds based on glucose oxidase assay method.
The determination of glucose level was done at intervals
i.e. 0 (fasting level), 30mins, 60mins, 120mins and
180mins.
Glycemic index calculation and statistics: Changes in
blood glucose concentration were calculated separately
for each post meal period by using the blood
concentration before meal (time 0) as a baseline.
Postprandial responses were compared for maximum
increase and incremental area under the glucose curves
for each food. The integrated area under the
postprandial glucose curve was calculated by the
trapezoidal method (Wolever et al., 1987). Area
increments under the curves for a given food were
determined for the 3 hour period after the meal. The
Omoregie and Osagie: Glycemic indices and glycemic load of some foods
712
Table 2: Proximate Analysis of Ten Processed Nigerian Foods (in Dry Weight Percent)
Food Moisture (g% Crude Crude Crude Carbohy-
Components Fresh Weight) Ash (g%) Protein (g%) Lipid (g%) Fibre (g%) drate (g%)
Starch (cassava) 75.10±0.10 1.06±0.06 2.46±0.62 1.55±0.35 2.25±1.75 92.68±0.05
Eba (cassava) 72.00±1.0 1.10±0.07 4.50±0.35 0.58±0.4 2.15±0.12 86.45±0.27
Amala (yam) 65.50±0.50 1.65±0.05 4.47±0.19 0.25±0.05 0.75±0.25 92.88±0.13
Agidi (maize) 84.80±0.24 2.90±0.10 6.82±0.27 0.35±0.05 1.75±1.2 88.18±0.12
Tuwo Masara (Maize) 74.50±0.5 1.63±0.01 9.94±1.91 0.65±0.25 1.7±0.25 86.03±0.03
Tuwo Gero (Millet) 65.00±0.05 1.58±0.01 9.51±0.23 0.45±0.05 1.03±0.03 87.43±0.06
Tuwo Dawa (Sorghum) 60.30±0.25 1.58±0.01 9.28±0.43 0.40±0.05 1.25±0.25 87.49±0.02
Tuwo Shinkafa (Rice) 73.50±1.50 1.65±0.03 9.23±0.43 0.90±0.20 1.0±0.50 87.22±0.12
Semovita (wheat) + 44.70±0.10 2.10±0.60 10.63±0.46 1.00±0.30 1.25±0.25 85.02±0.18
10% corn supplement
Semolina (wheat) 54.90±0.10 2.48±0.08 10.73±0.41 1.50±0.05 1.26±0.38 84.03±0.14
Values are expressed as mean±SEM (n = 3 determinations).
Table 3: Available Carbohydrate in Processed Foods (ServingTable 4: Glycemic Index and Glycemic Load of the Processed
Size) Food
Serving Size Glycemic Glycemic
Samples (Processed) (g) Food Samples Index Load
Starch (Cassava) 162.15 Starch (Cassava) 98.60±2.68 49.30±3.5
Eba (Cassava) 206.50 Eba (Cassava) 82.25±0.05 41.13±3.3
Amala (Plantain) 156.25 Amala (Yam) 84.35±2.68 42.18±4.2
Agidi (Maize) 373.13 Agidi (Maize) 92.30±0.05 46.15±3.1
Tuwo Masara (Maize) 158.00 Tuwo Masara (Maize) 86.80±0.5 43.40±1.5
Tuwo Gero (Millet) 163.40 Tuwo Gero (Millet) 93.60±2.25 46.80±3.4
Tuwo Dawa (Sorghum) 144.00 Tuwo Dawa (Sorghum) 85.30±1.05 42.65±3.2
Tuwo Shinkafa (Rice) 160.90 Tuwo Shinkafa (Rice) 95.30±1.25 47.65±2.2
Semovita (Wheat) + 10% Corn supplement 106.70 Semovita (Wheat) + 95.80±0.28 47.90±2.5
Semolina (Wheat) 131.90 10% Corn supplement
relative glycemic index of each food was calculated as
percent of the mean of individual areas under the
glucose response curves. (Wolever et al., 1987) The
increase in glucose response area was analysed
statistically using one way ANOVA and Scheffe’s test
(Allison et al., 1995).
Results
The results of the proximate analysis of the test food
samples are shown in Table 2. The proximate analysis
on the processed food from wheat, sorghum, rice and
maize showed low lipid contents compared to the
analysis of the unprocessed seeds (Ekpenyong, 1973;
Okoh, 1998). The cereal flours had higher crude protein
content than the tuber flours. From previous studies yam
and cassava tubers were naturally low in fat (Osagie and
Opute, 1981; Bradbury and Holloway, 1988). Thus, all
the processed powders used in making the
experimental pastes can be regarded as having low fat
content. The two test samples made from cassava tuber
(starch) and (eba) differed significantly in crude protein
content. Semolina and semovita are wheat products and
their proximate composition was similar.
The serving size for each meal was calculated from the
carbohydrate content (Table 3). The glucose
concentration attained after consumption of the test
foods and glucose (reference food) are graphically
displayed in Fig. 1 - 10. The Glycemic Index and
Semolina (Wheat) 95.28 ± 0.04 47.64±1.5
Values are mean ± SEM (n = 3 determinations)
Glycemic Load of the food samples were calculated
(Table 4). All the test samples are high Glycemic Index
foods. Cassava starch gave the highest GI value
followed by semovita. In two hours, these foods deliver
as much glucose as the free sugar (control) to the blood
system. In the absence of adequate insulin delivery,
these foods would certainly overwhelm the sugar
metabolic system. They are thus not considered suitable
or adequate meals for type II diabetics.
Discussion
Before plant foods are consumed by man, they are
generally processed. The processing methods include
cooking, (i.e. boiling, roasting, frying, steaming, baking,
autoclaving), drying, mashing, grinding into flour and
fermentation. In this study, the test foods were basically
dried, ground into flour, sieved and then reconstituted to
paste with hot water. Thus the particle sizes were
reduced, fine and the starch was retrograded
(gelatinized) to a variable extent. These treatments might
have led to their having high glycemic indices (Ludwig,
2003; Bjorck and Elmstahl, 2005). This is similar to
reports that increased processing and starch
retrogradation can affect GI (Foster-Powell et al., 2005).
Processing the seeds removes the fiber-rich outer bran
and the vitamin and mineral rich inner germ leaving
Omoregie and Osagie: Glycemic indices and glycemic load of some foods
713
Fig. 1: Graphical representation showing the glucoseFig. 4: Graphical representation showing the glucose
response area of test food A (Agidi) andresponse area of test food D (semovita) and
reference food (Glucose D). reference food (Glucose D).
Fig. 2: Graphical representation showing the glucoseFig. 5: Graphical representation showing the glucose
response area of test food B (Amala) andresponse area of test food E (Semolina) and
reference food (Glucose D). reference food (Glucose D).
Fig. 3: Graphical representation showing the glucoseFig. 6: Graphical representation showing the glucose
response area of test food C (Starch) andresponse area of test food F (Eba) and
reference food (Glucose D). reference food (Glucose D).
endosperm. This treatment caused reduction in particleincreasing the GI. Our study agrees with the finding in
size and faster gelatinization of starch, thereby Kenya where similarly processed maize flour
Omoregie and Osagie: Glycemic indices and glycemic load of some foods
714
Fig. 7: Graphical representation showing the glucoseFig. 9: Graphical representation showing the glucose
response area of test food G (Tuwo Rice) andresponse area of test food I (Tuwo maize) and
reference food (Glucose D). reference food (Glucose D).
Fig. 8: Graphical representation showing the glucoseFig. 10: Graphical representation showing the glucose
response area of test food H (Tuwo Millet) andresponse area of test food J (Tuwo rice) and
reference food (Glucose D). reference food (Glucose D).
and millet flour made into gruel had high GI (Foster-rise in blood sugar, with the result that one is lacking in
Powell et al., 2002). energy and hungry within a short time, thus the desire to
The test foods were swallowed without chewing.eat will arise. If this pattern is repeated, there is the
Chewing normally reduces the particle size of foods and likelihood of gaining weight as a result of constantly
facilitates mixture with salivary amylase, hence reducing eating. The overall effects are that the individual will gain
digestion time of carbohydrates. Despite the directweight i.e. obesity might result. It could trigger diabetes
swallowing of these test food pastes, they resulted in the in individuals that are prone to the disease, or worsen
same level of blood glucose as the reference sample,the management of the disease (Gilberston et al., 2001).
within two hours. This is in agreement with the fact thatType II diabetes which is associated with insulin
different food products with similar quality and type ofinsensitivity may also result in elevated blood sugar
carbohydrate form show different glycemic response. levels and increased insulin demand; thus
(Thorsdottir et al., 2005). Since these test foods wereoverburdening the ability of the pancreas to produce
reconstituted in hot water, the nature of starchinsulin. Reports by workers like Salmeron et al. (1997)
retrogradation or the production of resistant starch mayhave indicated a positive correlation between high GI
be similar. It is desirable that modern food processingand risk of type II diabetes. Again, the consumption of
techniques be modified so as to reduce preparationthe processed foods under reference in these studies
time while at the same time preserving slow digestionmight have serious health implications in such
properties. diseases like the heart diseases via insulin resistant
The health implications of the high GI of the processedsyndrome called metabolic syndrome X (Ludwig, 2003).
foods are that they could cause a fast and short - lived Additionally, high blood sugar levels have been
Omoregie and Osagie: Glycemic indices and glycemic load of some foods
715
associated with increased blood pressure, blood clotAOAC, 1983. Official Methods of Analysis, 13th Edn.
formation and reduced endothelial dependent blood flow
(Ludwig, 2003).
In recent years, the GI has been transformed by its
popularizers from a potentially useful tool in planning
diets for diabetic patients to a key player for the
prevention of diabetes, dyslipidemia, cardiovascular
disease and even certain cancers in the general
population. The debate concerns whether such a
transformation is justified. That is, whether it is wise and
reasonable to set as a public health policy for the entire
population the avoidance of certain foods because of
their high GI. To explore this question, one needs to
examine the supporting data, their quantity and quality,
their relation to causation and the possible presence of
confounders.
There are 2 theories about how high - GI foods increase
food intake. The first is that it is a result of the elevation
in glucose and the second, more commonly expressed
recently, is that it is the result of a high insulin response.
This high insulin response has been related to several
phenomena including increased food intake leading to
obesity (Roberts, 2000), hyperinsulinaemia leading to
insulin resistance (Frost et al., 1998), cell exhaustion
leading to type 2 diabetes (Salmeron et al., 1997),
dyslipidemia leading to coronary heart disease (CHD)
(Liu et al., 2001) and unknown factors leading to certain
kinds of cancers.
The foods tested in this study were selected to represent
the nutritional variability that adult Nigerians consume.
Many of them suffer from chronic diseases such as
coronary heart diseases, obesity and diabetes. Direct
relationship of these diseases to consumption of high
GI foods will require further enlarged and long-term
studies. There is also need for more research into the GI
of our locally consumed foods in order to produce data
that can effectively enable use of GI alongside other
dietary recommendations in the management and
prevention of diseases. In conclusion, this study could
assist food manufacturers and processors to develop a
greater range of low-GI processed foods from African
farm produce. The findings have obvious importance in
formulating rational dietary and therapeutic goals for
diabetic patients and others with clinical conditions
necessitating carbohydrate restriction.
Acknowledgement
We are grateful to our students (Atomatofa, E.U., Ibeji,
1
C.U., Awe, K., Omoregie, M.O., Akpeh, P.K. and
Uwaomah, N.) for their assistance with the organization
of the studies.
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... If this pattern is repeated, there is a likelihood of gaining weight as a result of constant eating. The overall effects are that the individual will gain weight i.e. obesity might result (Omoregie and Osagie, 2008). It could trigger diabetes in individuals that are prone to the disease, or worsen the management of the disease (Gilbertson et al., 2001).There are 2 theories about how high GI foods increase food intake (Omoregie and Osagie, 2008). ...
... The overall effects are that the individual will gain weight i.e. obesity might result (Omoregie and Osagie, 2008). It could trigger diabetes in individuals that are prone to the disease, or worsen the management of the disease (Gilbertson et al., 2001).There are 2 theories about how high GI foods increase food intake (Omoregie and Osagie, 2008). Firstly, it is a result of the elevation in glucose and secondly, it is the result of a high insulin response. ...
... Firstly, it is a result of the elevation in glucose and secondly, it is the result of a high insulin response. High insulin response has been related to several phenomena like increased food intake leading to obesity (Roberts et al., 2000), hyperinsulinaemia leading to insulin resistance (Frost et al., 1998), cell exhaustion leading to Type 2 diabetes (Salmeronet al., 1997) and unknown factors leading to certain cancers (Omoregie and Osagie, 2008). ...
Article
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Since foods like rice show wide variations in glycaemic index (GI) values, the objective of this work was to determine the GI of five (5) varieties of rice grown in Ebonyi State and compare with the GI of an imported brand of rice. Nineteen healthy subjects were fed 6 varieties of rice (Ikwo R8, Izzi Mass, Ikwo 306, Abakaliki brown rice, Ikwo Odime ala di and a commercially available imported brand) and a reference food (glucose), each containing 50g of available carbohydrates. Blood glucose was measured at 0, 15, 30, 45, 60, 90, 120 min after consumption following a fasting state. The GI was calculated using a standard equation. The GI values ranged from 40.01 to 94.17. Abakaliki brown rice and Ikwo 306 were classified as low GI rice, Izzi R8 was classified as medium GI rice while Izzi Mass, Ikwo Odime ala di and the commercially available imported brand were classified as high GI rice. The results obtained in this study suggest that type 2 diabetics should preferably consume Abakaliki brown rice, Ikwo 306 and Izzi R8 rice varieties which have low and medium GI values respectively.
... Glycemic Load (GL) is a property of the quantity of total carbohydrate in a food and it accounts for the amount of carbohydrate in a food and how each gram of carbohydrate in the food raises blood glucose levels. The GL is classied as follows: low (< 10), intermediate (11)(12)(13)(14)(15)(16)(17)(18)(19) and high (> 20), and is a metric used as a basis for weight loss, or diabetes control (5). Available evidence has shown that reductions in daily glycemic load may reduce the risk of noncommunicable diseases particularly type 2 diabetes, cancers and coronary heart disease (1). ...
... These differences may be due to variations in locations, growing conditions, differences in sugar composition, time of harvesting, duration and methods of storage of the fruits (11,18). Though jollof rice and wheat our dough are both cereal-based foods, the variation in the glycemic indices could be as a result of cooking methods and the presence of other ingredients in jollof rice (19). The high glycemic index in wheat may be attributed to the processing methods such as g r i n d i n g i n t o a p o w d e r e d f o r m ( 2 0 ) . ...
... Nevertheless, wheat our dough had a lower glycemic index compared with jollof rice, which may be due to the higher protein and lower carbohydrate contents in wheat our. The high glycemic index (97.37%) of wheat in this study is similar to 95.80% and 95.28% reported for wheat semovita and wheat semolina in an earlier study (19). A study in Botswana study also reported a higher glycemic index for wheat-based foods as 103.1% (21). ...
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Background: Information on glycemic index of staple foods are required to develop appropriate nutrition education materials to promote informed food choices. Objective: This study was designed to determine the glycemic index of four Nigerian staple foods, namely pineapple, banana, jollof rice and wheat flour dough. Method: The study was descriptive cross-sectional in design. Ten apparently healthy postgraduate 2 students (4 males and 6 females, 25.8±2.0 years; BMI: 22.68±2.69 kg/m ; fasting blood sugar: 92.1±3.38 mg/dl) randomly consumed 50 g available carbohydrate portions of test foods and glucose over a five-day period. Blood samples were collected in the fasting state and half-hourly over a 2-h period post-ingestion of test and reference foods to determine plasma glucose concentrations, incremental area under the glucose curve, glycemic index and glycemic load. Results: A 50 g available carbohydrate is equivalent to 176 g of banana, 199 g of jollof rice, 229 g of wheat dough and 322 g of pineapple. The Incremental Area Under the Curve for jollof rice, wheat dough and pineapple showed no significant difference when compared with glucose, while of banana was significant at P<0.05 when compared with glucose. The glycemic index was 94.88%, 97.37%, 98.9% and 99.3% and the corresponding glycemic load was 47.43%, 48.69%, 50.47% and 50.67%, for pineapple, wheat flour, jollof rice and banana, respectively.
... Glycemic Load (GL) is a property of the quantity of total carbohydrate in a food and it accounts for the amount of carbohydrate in a food and how each gram of carbohydrate in the food raises blood glucose levels. The GL is classied as follows: low (< 10), intermediate (11)(12)(13)(14)(15)(16)(17)(18)(19) and high (> 20), and is a metric used as a basis for weight loss, or diabetes control (5). Available evidence has shown that reductions in daily glycemic load may reduce the risk of noncommunicable diseases particularly type 2 diabetes, cancers and coronary heart disease (1). ...
... These differences may be due to variations in locations, growing conditions, differences in sugar composition, time of harvesting, duration and methods of storage of the fruits (11,18). Though jollof rice and wheat our dough are both cereal-based foods, the variation in the glycemic indices could be as a result of cooking methods and the presence of other ingredients in jollof rice (19). The high glycemic index in wheat may be attributed to the processing methods such as g r i n d i n g i n t o a p o w d e r e d f o r m ( 2 0 ) . ...
... Nevertheless, wheat our dough had a lower glycemic index compared with jollof rice, which may be due to the higher protein and lower carbohydrate contents in wheat our. The high glycemic index (97.37%) of wheat in this study is similar to 95.80% and 95.28% reported for wheat semovita and wheat semolina in an earlier study (19). A study in Botswana study also reported a higher glycemic index for wheat-based foods as 103.1% (21). ...
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Background: Information on glycemic index of staple foods are required to develop appropriate nutrition education materials to promote informed food choices. Objective: This study was designed to determine the glycemic index of four Nigerian staple foods, namely pineapple, banana, jollof rice and wheat flour dough. Method: The study was descriptive cross-sectional in design. Ten apparently healthy postgraduate 2 students (4 males and 6 females, 25.8±2.0 years; BMI: 22.68±2.69 kg/m ; fasting blood sugar: 92.1±3.38 mg/dl) randomly consumed 50 g available carbohydrate portions of test foods and glucose over a five-day period. Blood samples were collected in the fasting state and half-hourly over a 2-h period post-ingestion of test and reference foods to determine plasma glucose concentrations, incremental area under the glucose curve, glycemic index and glycemic load. Results: A 50 g available carbohydrate is equivalent to 176 g of banana, 199 g of jollof rice, 229 g of wheat dough and 322 g of pineapple. The Incremental Area Under the Curve for jollof rice, wheat dough and pineapple showed no significant difference when compared with glucose, while of banana was significant at P<0.05 when compared with glucose. The glycemic index was 94.88%, 97.37%, 98.9% and 99.3% and the corresponding glycemic load was 47.43%, 48.69%, 50.47% and 50.67%, for pineapple, wheat flour, jollof rice and banana, respectively.
... The GL is defined as: GI 9 carbohydrate (g) content per portion/100. As an example, Table 2 shows the relative contribution of commonly eaten foods (mostly starchy carbohydrates) in Nigeria to plasma glucose level [29]. Interestingly, GI values for different preparations of cassava (Manihot esculenta) range from 84 to 99 [29,30], with the lowest GI noted in eba and the highest in starch (also called Usi in the local language of Southern Nigeria). ...
... As an example, Table 2 shows the relative contribution of commonly eaten foods (mostly starchy carbohydrates) in Nigeria to plasma glucose level [29]. Interestingly, GI values for different preparations of cassava (Manihot esculenta) range from 84 to 99 [29,30], with the lowest GI noted in eba and the highest in starch (also called Usi in the local language of Southern Nigeria). Although both are derived from the same source (cassava), eba/gari is less processed than starch. ...
... Although both are derived from the same source (cassava), eba/gari is less processed than starch. The findings from this study underscore the importance of matching the insulin regimen to the meal plan [29]. In the African context, even though the foods may be minimally processed, the usual portions consumed per sitting tend to be enormous. ...
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The prevalence of diabetes in sub-Saharan Africa (SSA) is growing rapidly, and a steadily increasing number of adults are estimated to be living with type 2 diabetes mellitus (T2DM). Insulin therapy is the treatment of choice in patients who present with severe hyperglycaemia and in most of those who do not achieve target goals on oral hypoglycaemic agents. Initiating treatment with the appropriate type of insulin based on the meal patterns and lifestyle of the individual patient is a strategy that is more likely than others to improve glycaemic control and adherence. African cuisine typically has a high carbohydrate load. Given these predominantly carbohydrate-rich food habits, it is essential to modify this dietary pattern whilst at the same time ensuring that insulin therapy is initiated, titrated and maintained in a timely manner, as needed to suit the patient’s habits. To date, there are no published clinical guidelines to guide practitioners and patients on tailoring insulin to match the high carbohydrate content in African cuisine. To address this gap, we have reviewed current insulin therapy practices and propose a patient-centric guide to insulin therapy based on African cuisine. A literature search was conducted for studies published in English up to November 2019 that focused on the choice of insulin and its dosing in relation to African foods. All articles extracted were reviewed by an expert group. The recommendation of the expert group was that basal-bolus and premix insulin regimens are best suited to manage post-meal glycaemia in African cuisine. The timing and constituents of the meal, portion sizes, glycaemic load and glycaemic index of meals should be considered when choosing the type of insulin and insulin regimen. Assessment of individual preferences and comorbidities should be prioritised and form an integral part of diabetes management.
... Type 2 diabetes occurs either as a result of insufficient production of insulin or insulin resistance; insulin is the hormone produced by the pancreas, which regulates blood glucose levels by promoting the absorption of glucose from the blood into the liver, fat and skeletal muscle cells [22]. Cassava flour usually in form of ''garri" (the fried form of blended and processed cassava) is the most commonly consumed meal (starchy swallow used for soups) in Nigeria but its frequent consumption is usually discouraged in certain health conditions due to its high carbohydrate content of about 86% [23] and high glycemic index of 82 [24]. The glycemic index is a scale that ranks a carbohydrate-containing food by how much it raises blood sugar levels after it is consumed [25]. ...
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Healthy foods/diets are essential for maintaining good health and preventing diseases. Recently, there has been increase in the incidence of non-communicable diseases (NCDs) worldwide and this has brought about a lot of research on the effect of various foods on the nutritional status of people. Also, this has led to the development of healthier alternatives to manage such health conditions. The aim of this study was to comparatively evaluate the nutrient and anti-nutrient content of four commonly-consumed flours. Processed wheat, oat and unripe plantain flours were purchased from the market while fonio was purchased as whole grain before it was cleaned and milled into fine flour. Samples were stored at room temperature in properly-labelled, airtight sample glass bottles for analyses. Proximate composition was determined using standard methods of the Association of Analytical Chemists (AOAC). Micronutrients were estimated by Atomic Absorption Spectrophotometry, while anti-nutrients were determined using standard spectrophotometric methods. Inferential and descriptive statistics was used to analyze the data at a significance level of P<0.05. The proximate parameters varied significantly (P<0.05) among the flours. Carbohydrate varied from 76.38 + 0.59% (oat flour) to 87.65 + 0.36% (unripe plantain flour). Protein was least (8.75 + 0.25%) in unripe plantain flour and highest (16.08 + 0.26%) in wheat flour. Oat flour had significantly (P<0.05) higher content of beta-carotene (8.67 + 0.03mcg/100g), while wheat flour had significantly (P<0.05) higher content of calcium (45.36 + 0.29mg/100g). For the anti-nutrients, oat flour had the least content of hydrogen cyanide and oxalate, while wheat flour had the highest content of both. Generally, oat flour showed significantly (p<0.05) lower levels of the 6 anti-nutrients analyzed. From the results of this study, oat flour shows some food properties which may be beneficial for people who seek to reduce starch and caloric intake. Fonio flour could be a healthier alternative to most starchy meals, as a result of its good micronutrient content and preferred nutritional value. Consumption of these cereal flours as alternatives to some indigenous starchy meals should be encouraged for both adults and children.
... High glycaemic diet has been associated with increased metabolic disease risk.More so, foods with a high glycaemic index are known to accelerate beta-cell burnout especially in people with insulin deficiency or resistance through glucose toxicity.The glycaemic load of all the cassava meal studied was found to be significantly increased.The cassava dough, flakes, and cassava chips' glycaemic load were 46.62, 47.96 and 45.97, respectively. Similarly, Omoregie and Osagie;[14] in their study established that glycaemic load of cassava dough and flakes were 49.30 and 41.1, respectively. This implies that cassava food products have the potential of markedly elevating blood glucose because of its high glycaemic load which may inadvertently increase the demand for insulin on the pancreas which may lead to premature beta cell exhaustion especially in those that have some degree of insulin resistance.The insulin index of cassava dough, flakes garri and cassava chips were 55.83, 69.36 and 97.02, respectively. ...
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Background: The major challenge in Africa is the growing prevalence of metabolic syndrome which has been attributed to changing lifestyles in developing countries. The impact of the commonly available staple starchy food; eaten in this environment may also be a factor contributing to growing concerns of metabolic syndrome. Hence, the need to assess the affordable staple starchy foods. Cassava is the most consumed staple starchy food in our environment; therefore, our study evaluated its impact on glycaemic and insulin response in consumers.Aim: To determine Insulin Index (II), glycaemic profile (GP), glycaemic load (GL) and Glycaemic Index (GI), incremental glucose peak value (IGPV), and glycaemic profile index (GPI) of cassava food meals.Methods: Participants ingested three cassava processed products (cassava dough [fufu], chips [Abacha], and flakes [garri] (the equivalent of 50g glucose) and 50 g of reference meal (glucose solution). Fasting and post-prandial samples were taken for blood glucose and insulin however sample for glucose was taken at intervals of 30 mins to a maximum of 180mins and 120 mins for insulin, respectively.Result: The GI for cassava dough, flakes and chips were 93.26; 95.92 and 91.94, respectively. Their glycaemic load was 46.62; 47.96 and 45.97, respectively. The glycaemic profile index was 37.34; 41.41 and 46.19, respectively. In addition, the insulin index was 55.83; 69.36 and 97.02. The proximate analysis showed protein, moisture, fibre, fat, ash, and carbohydrate content as follows the cassava (%) (crude form) 1.075%; 72.00%; 0.80%; 0.58%; 0.35%; 25.07%, Chips 1.44%; 59.13%; 0.73%; 1.71%; 36.83%, flakes 1.82%; 67.36%; 0.15%; 0.91%; 0.25%; 39.64% and dough 1.56%; 67.51%; 0.21%; 0.52%; 0.20%; 30.22% respectively.Conclusion: II, GP, GL, and GI of cassava dough (fufu), cassava flakes(garri)and cassava chips (Abacha) were found to be high. Unregulated dietary intake in adults may lead to metabolic diseases.Keywords: Glycaemic index, Glycaemic load, Glycaemic profile, Cassava, Makurdi
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Sorghum requires fewer inputs for sustainable cultivation in harsh climates and has the potential to be utilized in modern food product innovations. Moreover, consumption of sorghum may elicit favorable health effects similar to other commonly consumed cereals, like wheat. Animal and human research exploring health effects of sorghum consumption indicates potential beneficial effects on blood glucose and lipid regulation, oxidative stress modulation, appetite regulation and weight management. However, a recent appraisal of the strength of evidence has not been conducted. Therefore, this study aims to evaluate the effects of sorghum consumption on metabolic indicators of chronic disease, including blood lipid and blood glucose levels, markers of oxidative stress, and factors associated with weight management. Using CINAHL, Cochrane Library, PubMed and MEDLINE databases, a systematic review of intervention studies published up to May 2020 was conducted and 16 interventional studies met the criteria for inclusion. Evidence for favorable effects of sorghum consumption on indicators of chronic disease, including blood glucose responses, markers of oxidative stress, satiety measures and weight management was demonstrated. Evidence from this systematic review may assist to promote sorghum's potential health benefits globally, including in food markets where it is underutilized, stimulating more sorghum-based food innovations in the future.
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Worldwide, congenital heart disease is a significant cause of morbidity and mortality in children being accountable for about one-third of all congenital defects. Malnutrition is known to be prevalent in this group of children owing to a multiplicity of factors. In this environment, because of the underlying burden of malnutrition, children with congenital heart disease may be more predisposed to malnutrition than in other climes. This study aimed to assess the nutritional status of children with congenital heart disease using anthropometric indices and to compare them with healthy age and sexmatched controls to elucidate possible factors influencing their nutritional status. Anthropometric indices of children with congenital heart disease and healthy age and sex-matched controls were taken. WHO and CDC charts were used to assess their nutritional status and subsequently, both groups were compared statistically. Two hundred and thirty children were recruited into the study, 115 each to the study and control groups, respectively. Underweight, stunting and wasting were present in 45.3%, 46.1% and 33% of the children with congenital heart disease compared to 5.2%, 7.8% and 3.5% respectively in the control group and these differences were statistically significant p<0.001. The presence of multiple lesions and ventricular septal defects were significant predictors of malnutrition in children with congenital heart disease. Malnutrition is significantly more common in children with congenital heart disease when compared to normal controls. Keywords: Congenital, heart, disease, malnutrition, children
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Objective: To determine the long-term effect of low glycemic index dietary advice on metabolic control and quality of life in children with type 1 diabetes. Research design and methods: Children with type 1 diabetes (n = 104) were recruited to a prospective, stratified, randomized, parallel study to examine the effects of a measured carbohydrate exchange (CHOx) diet versus a more flexible low-glycemic index (GI) dietary regimen on HbA(1c) levels, incidence of hypo- and hyperglycemia, insulin dose, dietary intake, and measures of quality of life over 12 months. Results: At 12 months, children in the low-GI group had significantly better HbA(1c) levels than those in the CHOx group (8.05 +/- 0.95 vs. 8.61 +/- 1.37%, P = 0.05). Rates of excessive hyperglycemia (>15 episodes per month) were significantly lower in the low-GI group (35 vs. 66%, P = 0.006). There were no differences in insulin dose, hypoglycemic episodes, or dietary composition. The low-GI dietary regimen was associated with better quality of life for both children and parents. Conclusions: Flexible dietary instruction based on the food pyramid with an emphasis of low-GI foods improves HbA(1c) levels without increasing the risk of hypoglycemia and enhances the quality of life in children with diabetes.
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The proposed mechanisms for the action of dietary fiber (DF) on the glycemic response suggest a nonlinear relationship between glycemic index (GI) and DF content. This relationship was analyzed by using the newly reported total DF (TDF) values, assuming a nonlinear regression curve. The empirical equation obtained was Y = 19.9X-0.322. Similar regression curves were also obtained for soluble DF (SDF) and insoluble DF (IDF). The two regression curves indicated that the correlation coefficient between observed GI and GI calculated from the IDF regression curve (-0.781) was virtually identical to that for SDF (-0.780), but a given content (eg, 5% vs available carbohydrate) of SDF gave a lower GI (39) than did IDF (48). This stronger dependency of GI on SDF suggests a major function of SDF in the TDF hypoglycemic effect. From the regression curve of GI vs TDF, we propose a supplemental GI to predict the glycemic response to foods with no published GI.
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The dietary fiber content and composition of 25 foods were related to their glycemic index (GI) to see whether the individual components of dietary fiber, specifically soluble fiber, would provide a better predictive capability of the glycemic response than their total dietary fiber content. Total dietary fiber was significantly related to GI (r = 0.461, p less than 0.05). Soluble fiber was not significantly related to GI (r = 0.308), and uronic acids in insoluble fiber were most closely related to GI (r = 0.584, p less than 0.01). Multiple-regression analysis showed that more variation of GI was explained by uronic acids in insoluble fiber (34%) than by total dietary fiber alone (21%, p = 0.05). The combination of pentoses, hexoses, and uronic acids in soluble and insoluble fiber explained only 50% of GI variability. In determining the potential metabolic effects of diet, physiologic assessment of foods is a useful supplement to chemical analysis of their dietary fiber content and composition.