Tuesday, July 14, 2009


Most of the consumers, if not all, believe that the cane sugar or glucose powder is the main source of energy with fast absorption and assimilation. The diabetics, whether of Type I or Type II, scrupulously avoid sweet foods made from sugar as they believe it can adversely affect their blood glucose control achieved through medication. It is least realized that any carbohydrate with high glycemic index(GI) can have equally same effect on blood sugar as human digestive and metabolic system is very efficient in extracting energy yielding sugars from the food ingested.
From the nutritional perspectives, a normal adult human requiring 2000 kC of energy per day, is expected to derive 50-60% of this need from carbohydrates working out to 275-300 gm. Complex carbohydrates should preferably be the source of 50% of daily energy demand while 10% can be accounted for by simple carbohydrates like sugars. Three mono saccharides, glucose, fructose and galactose are most important in human metabolism while three disaccharides, sucrose, maltose and lactose also play important role in the energy logistics of the body. Natural foods like sugar, corn syrup, HFCS, honey, malt, maple syrup, invert syrup and milk provide these vital energy ingredients directly while processed foods requiring sweet sensation use these ingredients to impart the desired organoleptic quality. Complex carbohydrates which are poly saccharides like starch, glycogen and dietary fiber need predigestion for deriving energy through the glucose route. While glycogen is confined to animal species, starch is wide spread in plants and they can be considered as the 'bland' sugar since they contain the basic sugar glucose in a bound form but is converted in vivo into glucose in the body.
Starchy foods after cooking lend themselves to further break down on ingestion using a series of amylolytic and hydrolytic enzymes like salivary amylase, pancreatic amylase and enzymes such as sucrase, lactase etc secreted by cells of the small intestine, ultimately yielding the mono saccharides for absorption across the intestinal wall into the blood. D-glucose and D-galactose are actively absorbed in the small intestine while D-fructose absorption is not still understood well. Only glucose goes directly to the cells requiring energy whereas galactose and fructose are transported to the liver for conversion to glucose before reaching the cells. It is a relevant question whether simple sugars can deliver energy faster than starchy foods for normal adults because of the high pitched and aggressive promotion of glucose as a palliative for "instant energy" in people during their normal work schedule. We have glucose biscuits, glucose drinks, glucose bars all aimed at the vulnerable consumer who can be carried away by the dicey commercials flashed across their television, day in and day out. Where does the truth lie?
When it comes to utilization of sugar by the body there is very little difference between sweet tasting foods and starchy foods because they go through the same route before manifesting as glucose in the blood. The only difference may be the time it takes for the first dose to reach the blood from the food material, glucose having a slight edge because of the time saved, which otherwise is necessary for conversion of starchy foods into glucose. Considering that glucose also has to reach the small intestine for absorption which cannot be instant, delay for starch derived glucose to appear in the blood may not be of much significance for a normal healthy person. Glycaemic Index (GI) which is a measure of efficiency of glucose absorption from foods can predict the behavior of each food vis-a-vis its ability to deliver glucose into the blood. The GI scale constructed with 138  as maximum for pure glucose gives an idea of different foods regarding their glucose 'yielding' behavior in the body. There are foods like rice cakes with a GI of 123, white bread ( GI 101), instant rice (GI128), puffed rice (GI 123) and many others which can match pure glucose in pumping 'energy' into the body. 
Food technologists are to day in a position to design foods with low as well as high GI suiting the needs of every consumer and already scores of such foods are in the market. It is ludicrous to go for a flavored glucose powder in the name of health while more nutritionally balanced wholesome food products are available, serving the same purpose! 

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