The Glycemic Index offers an interesting, and scientificallyvalid, way of assessing the types of carbohydrates we eat. Itmeasures and rates the way these carbohydrates enter thebloodstream. And in doing so offers a way of approaching a mealso that it may be both nutritionally valid, and keep hungerpangs at bay. This of course is one way of preventingovereating. And its a great way for parents to try and curbtheir children's desire to eat unhealthy food between meals.
The Glycemic Index rates carbohydrates as having either a high,low or medium glycemic index. And the idea is to eat more foodsthat have either a low or medium glycemic index, and less with ahigh one. Low glycemic index foods enter the bloodstream moreslowly, and so don't raise blood sugar levels like high glycemicindex foods.
So, what is a carbohydrate? All sugars, or foods that are brokendown into sugar, are carbohydrates. This includes regular sugar,glucose (often used in sports drinks), fructose, (in fruit),lactose, (found in milk and similar products like yoghurt),maltose, (found in malt which is often used to flavor cereals),all types of starches, from potatoes to noodles and pasta, andlegumes, such as lentils and peas (though these also containsome protein).
Fruit is considered to have a low GI (not fruit juice though).Interestingly though, recent research has found what theybelieve is a link between fructose and obesity. However, thetype of fructose studied was in corn syrup, which is a refinedand concentrated form of fructose. It also doesn't have thebeneficial fiber, antioxidants and other phytochemicals thatfruit does. This was also preliminary research done in an animalmodel, so it may not be valid for humans. Researchers from theUniversity of Florida found that fructose may make peoplebelieve they are hungrier than they should be. And when theseresearchers interrupted the way fructose was metabolized, therats they were working with did not put on weight, even thoughthey still ate fructose.
This is not the first research that has suggested fructose maybe linked to a propensity to put on weight, more so than othertypes of food. A study at the University of Cincinnati foundthat eating fructose (high fructose corn syrup), led to greaterfat storage. They say that the body processes fructosedifferently to other types of sugars, though again, it is notclear if this is mitigated by perhaps the lower concentration offructose in fruit as compared to the corn syrup used in thestudy.
The research from the University of Florida found that therewere higher levels of uric acid in the bloodstream after eatingor drinking fructose. This spike in uric acid affects insulin,by blocking it. Insulin regulates the way our cells store anduse fat. If uric acid levels are elevated a lot, then symptomsof metabolic syndrome can develop. These symptoms include highblood pressure, high cholesterol levels, as well as gaining alot of weight. What is of possible concern to people is thatfructose is used in a lot of soda drinks, so if you drink a lotof soda it is going to be quite easy to frequently spike uricacid levels in the blood. Metabolic syndrome is also a precursorof type 2 diabetes.
Signs of metabolic syndrome include fat on the abdomen, suchthat the waist appears as big as the hips or larger. There tendto be lower amounts of the good type of cholesterol in theblood, and high levels of triglycerides which make the blood'sticky'. Metabolic syndrome is associated with the way the bodyresponds to insulin, so that there are higher levels of glucosein the blood. All of these things can be tested by doctors.
References: 1.http://www.nutraingredients.com/news/ng.asp?n=64395&m=1NIED08&c=qgtqmovbyiaxdub
2. Australian Healthy Food, November 2005
3. Nature and Health, Oct/Nov 2005
About the author:Despite some claims the Zone Diet is a 'revised' version of theAtkins Diet, nothing could be further from the truth. Read this article for information on thezone diet and why I don't recommend Dr Atkins Diet, though it does have some goodpoints.
