Carbohydrates and Its Role in Obesity

What is the Role of Carbohydrates?

Obesity is a global epidemic with majority of the world's population in developed countries being over weight or obese!

According to the World Health Organization (WHO), obesity is rising globally with over 1 billion overweight adults out of which 300 million people are clinically obese. Obesity in itself is a disease that is responsible for many conditions ranging from hypertension and stroke to type 2 diabetes and cancer. It not only causes serious chronic illnesses, that reduce the quality of life, but also increases the risk of premature deaths. Diet and nutrition are the most significant factors responsible for an increased incidence in the number of overweight or obese people.

Although genetic, metabolic, social, cultural as well as environmental factors are associated with obesity, the major cause of obesity and increased weight is the consumption of energy dense and high calorie foods such as fats and sugars, in addition to decreased physical activity. This causes an energy imbalance or an excess of energy, which is stored in the body as fat.

Studies show that the quality of carbohydrates, rather than the quantity, determines whether a person gains weight and becomes obese. So, if you have a tendency to gain weight, you should refrain from eating white bread, pasta, chips, processed foods, cakes and cookies. This is because the high glycemic index in those foods causes a sudden increase in blood sugar. This increased blood sugar, if not utilized by the body, builds up as fat.

Similarly, processed carbohydrates or high calorie sugars predispose to the development of diabetes and cardiac diseases, besides causing obesity. David Ludwig, Director of the obesity program at Children's Hospital Boston says that the "yo-yo effect" that the high glycemic index carbohydrates have on the blood sugar stimulates fat production and inflammation, increases overall caloric intake and lowers insulin sensitivity.

A fiber-rich diet is important in the control and management of obesity. Fiber is a mixture of cellulose, lignin and polysaccharides called pentoses. It is the part of plant food which is indigestible and does not provide any calories. Fiber helps in the management of obesity as it provides bulk to food which makes you feel fuller while reducing the calories consumed. High fiber not only helps you to lose weight but prevents heart diseases as it reduces the absorption of lipids, proteins and simple carbohydrates which are recognized as risk factors. Certain pentoses present in fiber bind with cholesterol, thus reducing its absorption from the intestine. Daily intake of 10-12 grams of fiber is recommended. Fiber rich foods include wheat bran, whole wheat four, peas, carrots and most of the leafy green vegetables.

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