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Glycemic Indices and Glycemic Load of Some Nigerian Foods

May 2008
Pakistan Journal of Nutrition 7(5)

DOI:10.3923/pjn.2008.710.716

Authors:

University of Benin

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.

: Processing and Preparation of the Diet Pastes (Okoh, 1998)

…

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Pakistan Journal of Nutrition 7 (5): 710-716, 2008

ISSN 1680-5194

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.

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,

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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Full-text available

Oct 2021

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 Indices Of Pineapple, Banana, Jollof Rice and Wheat Flour Dough

Article

Full-text available

Oct 2021

African Cuisine-Centered Insulin Therapy: Expert Opinion on the Management of Hyperglycaemia in Adult Patients with Type 2 Diabetes Mellitus

Article

Full-text available

Nov 2020

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.

Comparative evaluation of the nutrient and anti-nutrient contents of edible flours consumed in Nigeria

Article

Full-text available

Feb 2021
AJFAND

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.

Effect of cassava on proximate composition, insulin index, glycemic profile, load, and index in healthy individuals: a cross-sectional study

Article

Full-text available

Jan 2021

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

Selected Nigerian Local Diet Effects on Blood Glucose Response of Undergraduates of Imo State University, Owerri

Article

Jan 2020

The effect of sorghum consumption on markers of chronic disease: A systematic review

Article

Jul 2021
CRIT REV FOOD SCI

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.

Anthropometric Assessment of Nutritional Status of Children with Congenital Heart Disease in the Niger Delta Region of Nigeria

Article

Full-text available

Sep 2020

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

Consumption Frequency and Proximate Composition of Some Carbohydrate Foods Most Consumed in Abidjan (Côte d’Ivoire)

Article

Jan 2020

The Effect of Flexible Low Glycemic Index Dietary Advice Versus Measured Carbohydrate Exchange Diets on Glycemic Control in Children With Type 1 Diabetes

Article

Full-text available

Jul 2001
DIABETES CARE

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.

The effect of starch-protein interaction in wheat on the glycemic response and rate of in vitro digestion

Article

Full-text available

Jun 1987

To determine the effect on blood glucose of removal of protein from wheat products, healthy volunteers took test meals of white bread made from either regular or gluten-free flour. After bread made from gluten-free flour, the blood-glucose rise was significantly greater. This corresponded with a significantly more rapid rate of digestion in vitro and reduced starch malabsorption in vivo as judged by breath-H2 measurements. Addition of gluten to the gluten-free bread mix did not reverse these effects. Factors associated with unprocessed wheat flour, such as the natural starch-protein interaction, may therefore be important in wheat products in reducing both their rate of absorption and glycemic response. They may have implications in the dietary management both of diabetes and of diseases where small intestinal absorptive capacity is impaired.

The Chemical Composition of Tropical Root Crops

Article

Jan 1988

J.H. Bradbury

The chemical composition of tropical root crops

Article

Jan 1988

J.H. Bradbury

Total lipid and fatty acid composition of tropical tubers

Article

Jan 1981

Depletion and disruption of dietary fibre. Effects on satiety, plasma-glucose, and serum-insulin

Article

Nov 1977

Ten normal subjects ingested test meals based on apples, each containing 60 g available carbohydrate. Fibre-free juice could be consumed eleven times faster than intact apples and four times faster than fibre-disrupted purée. Satiety was assessed numerically. With the rate of ingestion equalised, juice was significantly less satisfying than purée, and purée than apples. Plasma-glucose rose to similar levels after all three meals. However, there was a striking rebound fall after juice, and to a lesser extent after purée, which was not seen after apples. Serum-insulin rose to higher levels after juice and purée than after apples. The removal of fibre from food, and also its physical disruption, can result in faster and easier ingestion, decreased satiety, and disturbed glucose homoeostasis which is probably due to inappropriate insulin release. These effects favour overnutrition and, if often repeated, might lead to diabetes mellitus.

Glycemic response and fiber content of some foods

Article

Sep 1991

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.

The glycemic index: Methodology and clinical implications

Article

Dec 1991

There is controversy regarding the clinical utility of classifying foods according to their glycemic responses by using the glycemic index (GI). Part of the controversy is due to methodologic variables that can markedly affect the interpretation of glycemic responses and the GI values obtained. Recent studies support the clinical utility of the GI. Within limits determined by the expected GI difference and by the day-to-day variation of glycemic responses, the GI predicts the ranking of the glycemic potential of different meals in individual subjects. In long-term trials, low-GI diets result in modest improvements in overall blood glucose control in patients with insulin-dependent and non-insulin-dependent diabetes. Of perhaps greater therapeutic importance is the ability of low-GI diets to reduce insulin secretion and lower blood lipid concentrations in patients with hypertriglyceridemia.

Effects of Dietary Carbohydrate and Fat Intake on Glucose and Lipoprotein Metabolism in Individuals With Diabetes Mellitus

Article

Oct 1991
DIABETES CARE

The dietary treatment of individuals with diabetes remains a controversial issue. The major emphasis in recent years has been on the reduction of total fat and saturated fat and replacement with complex carbohydrate. The rationale for this approach is based on the premise that such diets will reduce the risk of coronary artery disease (CAD) by reducing total and low-density lipoprotein cholesterol concentrations. In this article, we review the available data and conclude that there is little evidence to support the notion that low-fat high-carbohydrate diets per se lead to any reduction in the risk for CAD in individuals with diabetes. The only data indicating that low-fat high-carbohydrate diets lead to beneficial effects on carbohydrate and lipoprotein metabolism are confounded either by the lack of suitable experimental control, by the fact that diets also differed in the type of dietary fat and amount of dietary cholesterol, or were enormously enriched in dietary fiber. When these factors are taken into consideration, there appears to be little evidence in support of the view that substituting carbohydrate for fat in the diets of individuals with diabetes results in any measurable beneficial effect. Indeed, it could be argued that the most characteristic defects in carbohydrate and lipoprotein metabolism are exacerbated in response to low-fat high-carbohydrate diets. Alternatively, the data presented herein strongly suggest that diets containing conventional quantities of fat, in which saturated fat is replaced by unsaturated fat and dietary cholesterol reduced, would result in the desired reductions to total and low-density lipoprotein cholesterol concentrations without the adverse effects of increased postprandial glucose and insulin concentrations, increased fasting and postprandial total and very-low-density lipoprotein triglyceride concentrations, and decreased fasting high-density lipoprotein cholesterol concentrations.

Relationship between dietary fiber content and composition in foods and the glycemic index

Article

Feb 1990

Thomas Wolever

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.