Article

Glycaemic Index and Load of Acha (Fonio) in Healthy and Diabetic Subjects

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Abstract

Acha or Fonio is a popular cereal consumed by the diabetics' subjects and it contributes substantially to the total food intake of the diabetic subjects in Nigeria. It has become very expensive as the only major acceptable carbohydrate food and therefore it is necessary to determine its glycaemic index and load of Acha among the Type II diabetic and healthy control subjects. Ten volunteer Type II diabetics and seven healthy subjects consented for the metabolic studies. Fifty grams available carbohydrate of Acha (Digitaria exilis Stapf) meal and okra (Abelmoschus esculentus L Moench) soup was used as test food while 50 grams of glucose served as the reference food. The blood glucose responses were used to calculate the area under the blood glucose curve (AUC) to determine the glycaemic index of the meal. The percentage of carbohydrate in the meal multiplied by glycaemic index was equal to glycaemic load. The glycaemic index in Type II diabetics and healthy subjects were found to be 49 and 35 respectively. The glycaemic load of Acha meal was 17.5 for control groups and 24.5 in Type II diabetic subjects. The Glycaemic index (GI) of Acha meal is low in both Type II diabetics and healthy subjects. The glycaemic load of the Acha (D exilis ) meal is just enough for control and high for the Type II diabetic subjects. The GL could explain why despite the consumption of Acha by Type II diabetic their blood glucose could not be controlled because they regularly consume it in their homes more than the portion size served in this research. Therefore, it is necessary to adjust the quantity of Acha (D. exilis) meal consumed by diabetics' subjects.

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... Fonio grains are mostly consumed in whole grain form. Different health effects of fonio grains and related products have been reported (Adams & Yakubu, 2020;Alegbejo, Ameh, Ogala, & Ibrahim, 2011;Chukwurah et al., 2016;Koreissi-Dembélé et al., 2013;N'Dri et al., 2013;Sartelet et al., 1996). The presence of polyphenols in fonio grains leads to antioxidant and free radical scavenging activities (Chukwurah et al., 2016;Glew et al., 2013;N'Dri et al., 2013). ...
... Fonio showed antidiabetic potential and glycemic control capacity (Adams & Yakubu, 2020;Alegbejo et al., 2011;Ibrahim & Saidu, 2017). Glycemic property of differently processed (cooked, dehulled, or ground) white fonio grains was measured in vivo using diabetic Wistar rats (Ibrahim & Saidu, 2017). ...
... This effect could be largely due to the dietary fiber present in the hulls. The glycemic response of white fonio was measured in humans (Nigerians) with (n = 10) or without (n = 7) type II diabetes (Alegbejo et al., 2011). The glycemic indices (GIs) of the healthy and diabetic subjects were 35 and 49, respectively. ...
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Fonio grains are a type of small‐seeded cereals native to Western Africa and are important cereal crops for food security. The two species are white fonio (Digitaria exilis) (commonly called acha) and black fonio (Digitaria iburua) (commonly called iburu). As a novel food, fonio has attracted attention from other parts of the world due to their attractive nutritional properties (e.g., in whole grain form and being gluten free) and potential food applications. The information regarding the functional properties and applications of fonio is rather scattered. This review summarizes the chemical composition, physicochemical and nutritional properties, and diverse food applications of fonio. The nutritional composition and processing properties of fonio are similar to other cereals. Fonio has potential to be complementary to major cereals for diverse food uses. There are research opportunities to better explore fonio grains for value‐added applications.
... Nationally, it is extensively cultured in the calm borders of the Plateau state including other states like Taraba, Kaduna, Niger, Jigawa and Kebbi where it is involved in the production of lettuce, cabbage, soup, yam meal, cake or other wheat products. Published works on D. exilis grains include anti-stroke activity (Taylor et al., 2006), antidiabetic role (Adams and Yakubu, 2020), physiochemical, lipid and amine, chemical component and oxygen inhibitor status (Glew et al., 2013), microstructure and nutritional component (Ballogou et al., 2013), postprandial proportion and postprandial load of D. exilis in normal and diseased models (Alegbejo et al., 2011), mutilation of salivary ptyalin from D. exilis (Egwim and Oloyede, 2008). Olagunju et al. (2018) have emphasized the 70:30 proportion augmentation of D. exilis flour with Cajanus cajan wheat which displayed the greatest repressive role opposed to salivary ptyalin and intestinal maltase and thus effective as nutritive diet in the healing of high blood sugar and as prophylaxis for related degenerative disorders. ...
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Digitaria exilis grains rich in polyphenol have been speculated among some traditional practitioners of Northern Nigeria to aid in treating constipation. Hence, this study aims at assessing the anti-constipation property of polyphenol-rich extract of Digitaria exilis grains (PREDEG) in rifaximin-induced constipated rat. Thirty (30) Wistar rats of both sexes (143.84 ± 2.62 g) were assigned into 6 categories, A to F, of 5 rats each. Category A (control) received 0.4 ml of saline. Constipations were induced in categories B to F by oral administration of rifaximin (2 mg/kg in saline for 48 h) and treated respectively with saline, glycerine (reference drug at 40 mg/kg), 50, 150 and 250 mg/kg of PREDEG (extracted via standard methods). All the treatments were given orally for 6 days using oral device. Rifaximin-induced constipation significantly (p < 0.05) decreases the feed and water intake, faecal quality, bodyweight and gastrointestinal flow proportion. All these alterations were attenuated dose-dependently, when co-treated with PREDEG and highest activity recorded at 250 mg/kg compared to reference drug. The data present polyphenol-rich extract of D. exilis grains as a potent anti-constipation agent and may act probably by lowering gastrointestinal dysmotility. This validates its traditional use in the treatment of constipation mostly in the Northern part of Nigeria.
... Acha (Digitaria exilis) also known as Fonio, Findi, Funde, Pom, and Kabug is a highly nutritious cereal crop of West African origin belonging to the family Graminaea (Oyetayo and Agbaje 2012;Malomo et al. 2018) is a lesser-known cereal rich in vitamins, minerals, fiber, carbohydrate, protein, amino acids. It is important because it is high in methionine and cysteine lacking in wheat, rice, maize and other cereal crops and also have low glycemic index which could be an advantage in type II diabetic condition (Alegbejo et al. 2011;Ukeyima 2019). Fermentation of cereals has been reported to increase acidity, total free amino acids and their derivatives by proteolysis and/or by metabolic synthesis. ...
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This research investigated effect of fermentation time and cereal type on the total reducing sugar (TRS), total sugar (TSS), and total free amino acid (TFA) during the production of ogi. The result showed that TFA generally increased with increase in fermentation time (7.916-17.596 mg/g). Maize, acha and sorghum ogi had the lowest total reducing sugar (TRS) at 0 h (16.927glucose mg/g), 12 h (16.655 glucose mg/g) and 48 h (18.212 glucose mg/g) respectively and TSS was lowest in acha ogi from 12 h to 48 h (33.191-34.370 glucose mg/g). Principal component analysis and Agglomerative hierarchical clustering were used to evaluate the variability in sugar and amino acid contents and ranked the contributions of the variables. The factors were divided into four principal components with cumulative variance contribution rate of 87.47%. The result showed that acha and sorghum ogi had lower sugar content than maize ogi during fermentation. This research suggested that maize, acha and sorghum can be used in the production of cereal based ogi for weaning food at 48 h due to high free amino acid content, and also advanced the use of acha in production of ogi for diabetic patients due to its low total sugar content.
... Acha (Digitaria exilis) also known as Fonio, Findi, Funde, Pom, and Kabug is a highly nutritious cereal crop of West African origin belonging to the family Graminaea (Oyetayo and Agbaje 2012;Malomo et al. 2018) is a lesser-known cereal rich in vitamins, minerals, fiber, carbohydrate, protein, amino acids. It is important because it is high in methionine and cysteine lacking in wheat, rice, maize and other cereal crops and also have low glycemic index which could be an advantage in type II diabetic condition (Alegbejo et al. 2011;Ukeyima 2019). Fermentation of cereals has been reported to increase acidity, total free amino acids and their derivatives by proteolysis and/or by metabolic synthesis. ...
Article
Full-text available
This research investigated effect of fermentation time and cereal type on the total reducing sugar (TRS), total sugar (TSS), and total free amino acid (TFA) during the production of ogi. The result showed that TFA generally increased with increase in fermentation time (7.916 – 17.596 mg/g). Maize, acha and sorghum ogi had the lowest total reducing sugar (TRS) at 0 h (16.927glucose mg/g), 12 h (16.655 glucose mg/g) and 48 h (18.212 glucose mg/g) respectively and TSS was lowest in acha ogi from 12 h to 48 h (33.191 - 34.370 glucose mg/g). Principal component analysis and Agglomerative hierarchical clustering were used to evaluate the variability in sugar and amino acid contents and ranked the contributions of the variables. The factors were divided into four principal components with cumulative variance contribution rate of 87.47%. The result showed that acha and sorghum ogi had lower sugar content than maize ogi during fermentation. This research suggested that maize, acha and sorghum can be used in the production of cereal based ogi for weaning food at 48 h due to high free amino acid content, and also advanced the use of acha in production of ogi for diabetic patients due to its low total sugar content.
... These three meals used in this work were reported as low glycaemic index meals by Alegbejo et al. (2009aAlegbejo et al. ( , 2009bAlegbejo et al. ( and 2011 and also all the meals had high glycaemic load. It has been shown that when lowglycaemic carbohydrates are incorporated into an energy-deficient diet, there is a greater fall in insulin resistance than can be accounted for by weight loss alone (Slabber et al., 1994). ...
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Dünya toplumları, tahıl mahsullerine bağımlı olmaya ve tahıl kökenli gıdalardan beslenmeye devam etmektedir. Küresel bazda yaygın olarak yetiştirilip tüketilen mısır, buğday ve pirinç gibi tahıl ürünlerinin yanında nadir tahıllar olarak adlandırılan bazı türler de, yoksul toplumların gıda temininde önemli bir rol oynamaktadır. Fonio tahılı tek yıllık bir bitki olup Poaceae familyasına aittir. Batı Afrika kökenli küçük tohumlu bir tahıl olan fonio bölge halkı için hayati bir besin kaynağıdır. Beyaz fonio acha (Digitaria exilis) ve siyah fonio iburu (Digitaria iburua) olmak üzere iki fonio çeşidi yaygın biçimde kullanılmaktadır. Bir tahıl olarak yakın zamanda tanınan fonio, araştırmacıların ilgisini çeken büyük bir potansiyel ve önemli besinsel özellikler sunmaktadır. Bu tahılın besin bileşimi ve işleme özellikleri diğer tahıllarınkine benzerdir. Ayrıca fonio tahılı, çeşitli gıda formülasyonlarında kullanıldığında buğday ve pirinç gibi başlıca tahılların sunduğu özellikleri tamamlama kapasitesine sahiptir. Gıda endüstrisinde sağlıklı gıda anlayışına uygun yeni tip ürünler ve fonksiyonel nitelikte gıdalar, son dönem araştırmalarında önemli bir yere sahiptir. Bu nedenle, fonio gibi unutulmuş veya yeterince tanınmamış tahılların, bu bağlamda önemli bir potansiyeli vardır. Bu çalışma, fonio tahılının kimyasal, fizikokimyasal ve besinsel özelliklerinin bir özetini sunarken, farklı gıda ürünlerinde uygulanmasına ilişkin araştırmalardan elde edilen veri ve bulguları içermektedir.
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Background and aims: The global prevalence of diabetes mellitus is on the increase, and Africa, particularly Nigeria is not left out. The management of the disease using a diabetes drug is often a hard choice to make for many. Information on the right food is inevitably important, as eating some type of food and avoiding or limiting some could help manage diabetes. Therefore, this study investigated glycemic indices of commonly consumed staples in Nigeria. Methods: Databases like PubMed, ScienceDirect, Google scholars, African journal online and Nigerian journal online was used to search for relevant information. Keywords like: nutritional management, diabetes in Nigeria, quality of life, prevalence, glycemic index, foods and diabetes, macronutrients and diabetes, were used separately or combined to obtain the relevant information. Results: Findings from literature search revealed that the glycemic indices of many staples such as Rice dough (Tuwo shinkafa), maize dough (tuwo masara), millet dough (tuwo gero), yam/cassava flour (amala), pounded fermented cassava (fufu, akpu), garri (eba), african salad (abacha), pounded yam (ema, iyan), rice (shinkafa, isesi), beans (wake, ewa, Agwa), and plantain (Ojoko, Ogbagba, Ogede) that are consumed in different parts of Nigeria are high (75.0%-97.0%). However, available information revealed that less commonly consumed foods like, Maize pudding (igbangwu), dried beef floss (dambu), Fonio (acha), bean pudding (moi-moi) and Tom Brownvita (Turnbrown) exhibit lower glycemic indices (14.1%-52.9%). Conclusions: This study revealed the few among several local foods in Nigeria that are low in glycemic indices that could be useful in the management of Type-2 diabetes. However, these foods may require further certification by appropriate authorities and agencies to enable persons with diabetes, particularly in Nigeria make informed choices on the right food to consume.
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Proteins from Digitaria exilis (acha) and durum wheat were characterised by gel filtration (GF), sodium dodecyl sulphate polyacrylamide-gel electrophoresis (SDS-PAGE), and acid-PAGE. The proteins of acha show compositional and solubility differences from those of durum studied under the same conditions. From the acid-PAGE results, 1M urea extracted the gliadins of wheat. However, a urea concentration of up to 6M was necessary to solubilise acha proteins corresponding to alpha-gliadins. The proportion of glutelins and residue proteins in acha was higher than all other Osborne fractions. The amino-acid composition for acha-protein fractions showed significantly greater amounts of hydrophobic and sulphur amino acids than those in durum. The enhanced solubility of acha proteins in urea or propanol (in the presence of a reducing agent) suggests that hydrophobic as well as covalent disulphide interactions are responsible for the relative insolubility of acha proteins in conventional solvents. SDS-PAGE analysis of wholemeal acha flour revealed that a major component with molecular weight 25.2 kDa, which was absent in durum wheat, forms a basic structural component of acha storage proteins. GF and SDS-PAGE of the four soluble-protein factions for acha proteins (albumin, globulin, prolamin, and glutelin) showed that similar-molecular-weight components (obtained by GF) were relatively heterogeneous by SDS-PAGE.
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To access publisher full text version of this article. Please click on the hyperlink in Additional Links field The glycaemic index (GI) concept is based on the difference in blood glucose response after ingestion of the same amount of carbohydrates from different foods, and possible implications of these differences for health, performance and well-being. GI is defined as the incremental blood glucose area (0-2 h) following ingestion of 50 g of available carbohydrates in the test product as a percentage of the corresponding area following an equivalent amount of carbohydrate from a reference product. A high GI is generally accompanied by a high insulin response. The glycaemic load (GL) is the GI x the amount (g) of carbohydrate in the food/100. Many factors affect the GI of foods, and GI values in published tables are indicative only, and cannot be applied directly to individual foods. Properly determined GI values for individual foods have been used successfully to predict the glycaemic response of a meal, while table values have not. An internationally recognised method for GI determination is available, and work is in progress to improve inter- and intra-laboratory performance. Some epidemiological studies and intervention studies indicate that low GI diets may favourably influence the risk of chronic diseases such as diabetes and coronary heart disease, although further well-controlled studies are needed for more definite conclusions. Low GI diets have been demonstrated to improve the blood glucose control, LDL-cholesterol and a risk factor for thrombosis in intervention studies with diabetes patients, but the effect in free-living conditions remains to be shown. The impact of GI in weight reduction and maintenance as well as exercise performance also needs further investigation. The GI concept should be applied only to foods providing at least 15 g and preferably 20 g of available carbohydrates per normal serving, and comparisons should be kept within the same food group. For healthy people, the significance of GI is still unclear and general labelling is therefore not recommended. If introduced, labelling should be product-specific and considered on a case-by-case basis
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The insulin resistance syndrome has recently been implicated in the etiology of coronary heart disease, with a possible metabolic defect at the level of the adipocyte. We report the effects of a low- versus high-glycemic-index (LGI and HGI, respectively) diet on insulin and glucose response as assessed by oral glucose tolerance test (OGTT) and insulin-stimulated glucose uptake in isolated adipocytes in a group of 32 patients with advanced coronary heart disease. The area under the insulin curve following OGTT was significantly reduced after 4 weeks in the LGI group (P < .03), but not in the HGI group. Insulin-stimulated glucose uptake in isolated adipocytes harvested from a presternal fat biopsy was significantly greater following the LGI diet (P < .05). This study demonstrates that simple short-term dietary measures can improve insulin sensitivity in patients with coronary heart disease.
Article
The glycemic index (GI) is a classification of foods based on their blood glucose-raising potential. The American Diabetes Association (ADA) has questioned the clinical utility of the GI and recommends that priority should be given to the amount rather than the source of carbohydrate. Some have interpreted this to mean that all carbohydrates have a nearly equal impact on blood sugar, and some feel that the GI is now a dead issue. Nevertheless, the reasons for questioning the clinical utility of the GI are unfounded because of the following: 1) they are based on studies of single test meals, which provide insufficient evidence on which to base dietary recommendations; 2) they are based on a faulty interpretation of the studies actually cited as evidence; 3) they take no account of better designed studies showing that the GI does apply in mixed meals; and 4) they take no account of studies showing that a low-GI diet improves overall blood glucose control in persons with diabetes. The GI is a valid and potentially useful concept, but is also deceptively complex. There are a number of unresolved problems and unanswered questions, and the appropriate place for the GI in patient education is not known. However, progress cannot be made without balance and objectivity.
Article
Diet influences the prevalence of coronary heart disease (CHD). Insulin sensitivity and concentrations of HDL cholesterol, two metabolic predictors of CHD, are also influenced by diet. Dietary carbohydrates with a high glycaemic index cause a high postprandial glucose and insulin response, and are associated with decreased insulin sensitivity and an increased risk of CHD. This study examined whether the glycaemic index of dietary carbohydrates is a determinant of serum HDL-cholesterol concentrations. Dietary, anthropometric, and biochemical data from the 1986-87 Survey of British Adults (n=2200) were reanalysed by a multiple regression model, which examined the relation between serum total cholesterol, HDL-cholesterol, and calculated LDL-cholesterol concentrations and various dietary characteristics, including the type of carbohydrate, the glycaemic index, and fat intake. Among the 1420 participants with complete data, there was a significant negative relation between serum HDL-cholesterol concentration and the glycaemic index of the diet for both men (regression coefficient -0.00724 [95% CI -0.0101 to -0.00434], p=0.02) and women (-0.01326 [-0.0162 to -0.0102], p<0.0001). No other significant relation was found with total cholesterol or LDL-cholesterol concentration or with any other dietary carbohydrate or fat constituent. In a cross-sectional study of middle-aged adults, the glycaemic index of the diet was the only dietary variable significantly related to serum HDL-cholesterol concentration. Thus, the glycaemic index of the diet is a stronger predictor than dietary fat intake of serum HDL-cholesterol concentration.
Article
Dietary glycemic index, an indicator of the ability of the carbohydrate to raise blood glucose levels, and glycemic load, the product of glycemic index and carbohydrate intake, have been positively related to risk of coronary heart disease. However, the relationships between glycemic index and glycemic load and high-density lipoprotein cholesterol (HDL-C) concentration in the US population are unknown. Using data from 13 907 participants aged 20 years and older in the Third National Health and Nutrition Examination Survey (1988-1994), we examined the relationships between glycemic index and glycemic load, which were determined from a food frequency questionnaire and HDL-C concentration. The age-adjusted mean HDL-C concentrations for increasing quintiles of glycemic index distribution were 1.38, 1.32, 1.30, 1.26, and 1.27 mmol/L (P<.001 for trend). (To convert millimoles per liter to milligrams per deciliter, divide by 0.0259.) After additional adjustment for sex, ethnicity, education, smoking status, body mass index, alcohol intake, physical activity, energy fraction from carbohydrates and fat, and total energy intake, the mean HDL-C concentrations for ascending quintiles of glycemic index were 1.36, 1.31, 1.30, 1.27, and 1.28 mmol/L (P<.001 for trend). Adjusting for the same covariates and considering glycemic index as a continuous variable, we found a change in HDL-C concentration of -0.06 mmol/L per 15-unit increase in glycemic index (P<.001). The multiple R(2) for the model was 0.23. Similarly, the multivariate-adjusted mean HDL-C concentrations for ascending quintiles of glycemic load distribution were 1.35, 1.31, 1.31, 1.30, and 1.26 mmol/L (P<.001 for linear trend). The inverse relationships between glycemic index and glycemic load and HDL-C persisted across all subgroups of participants categorized by sex or body mass index. These findings from a nationally representative sample of US adults suggest that high dietary glycemic index and high glycemic load are associated with a lower concentration of plasma HDL-C.
Article
The use of diets with low glycemic index (GI) in the management of diabetes is controversial, with contrasting recommendations around the world. We performed a meta-analysis of randomized controlled trials to determine whether low-GI diets, compared with conventional or high-GI diets, improved overall glycemic control in individuals with diabetes, as assessed by reduced HbA(1c) or fructosamine levels. Literature searches identified 14 studies, comprising 356 subjects, that met strict inclusion criteria. All were randomized crossover or parallel experimental design of 12 days' to 12 months' duration (mean 10 weeks) with modification of at least two meals per day. Only 10 studies documented differences in postprandial glycemia on the two types of diet. Low-GI diets reduced HbA(1c) by 0.43% points (CI 0.72-0.13) over and above that produced by high-GI diets. Taking both HbA(1c) and fructosamine data together and adjusting for baseline differences, glycated proteins were reduced 7.4% (8.8-6.0) more on the low-GI diet than on the high-GI diet. This result was stable and changed little if the data were unadjusted for baseline levels or excluded studies of short duration. Systematically taking out each study from the meta-analysis did not change the CIs. Choosing low-GI foods in place of conventional or high-GI foods has a small but clinically useful effect on medium-term glycemic control in patients with diabetes. The incremental benefit is similar to that offered by pharmacological agents that also target postprandial hyperglycemia.