Research shows that the amount and the type of carbohydrate in food affects blood glucose levels. This is of utmost importance for diabetics. Not all digestible carbohydrates raise the blood sugar to the same extent and can be classified on the basis of their effect on blood sugar
Studies have shown that eating healthier carbohydrate-rich foods can help ward off a host of chronic conditions. This article deals with what happens to carbohydrates once they are in the body and their effect on blood sugar levels.
When foods containing carbohydrates are eaten, the digestive system breaks down the digestible ones, namely, starch and sugars into glucose which then enters the blood. As the blood sugar levels rise, the beta cells in the pancreas secrete the hormone insulin which signals the cells to absorb the blood sugar for energy or storage causing the blood sugar levels to drop. As the blood sugar levels drop, the alpha cells in the pancreas start making glucagon, a hormone that causes the liver to start breaking the glycogen stores into glucose thereby raising blood sugar levels to normal. This interplay of insulin and glucagon ensures that cells throughout the body especially in the nervous system and brain have a steady supply of glucose and energy for their normal functioning.
In people with diabetes, this cycle does not work properly. In individuals with Type 1 diabetes, insufficient insulin is produced and the cells cannot utilise the blood sugar properly hence there is a tendency for the blood sugar levels to be high. In individuals who develop Type 2 diabetes, initially their cells do not respond to insulin’s signal to utilise the blood sugar. This condition is known as insulin resistance and causes the blood sugar and insulin levels to stay high long after eating. Overtime, insulin resistance causes the beta cells to wear out leading to insufficient insulin production. Insulin resistance is not just a blood sugar problem. It has also been linked to the metabolic syndrome which is a group of conditions – high blood pressure, high blood sugar levels, high levels of triglycerides, low levels of HDL (good) cholesterol, and abdominal obesity. On its own and as part of the metabolic syndrome, insulin resistance can lead to Type 2 diabetes, heart disease, and possibly some cancers. Heredity, sedentary lifestyles, obesity and diets rich in processed carbohydrates can each promote insulin resistance but a combination of all these factors is worse.
Research shows that the amount and the type of carbohydrate in food affects blood glucose levels. This is of utmost importance for diabetics. Not all digestible carbohydrates raise the blood sugar to the same extent and can be classified on the basis of their effect on blood sugar. This is measured in terms of Glycemic Index (GI).
The glycemic index or GI is a ranking of carbohydrates on a scale from 0 to 100 according to the extent to which they raise blood sugar levels after eating in comparison to a reference food either glucose or white bread. GI is not related to whether the carbohydrate is simple or complex. Foods with low GI keep one feeling full for a longer time, improve weight loss and help control Type 2 diabetes. Research studies have shown that diets rich in high GI foods cause rapid increase in blood sugar levels and insulin requirements and have been linked to an increased risk for obesity, diabetes, heart disease. The preliminary results of other research studies have shown that diets with high GI are linked to age-related macular degeneration (AMD), infertility and colorectal cancers.
To be continued…
(Writer is a consultant nutritionist with 19 years of experience, practicing at Panaji and can be contacted on firstname.lastname@example.org)