How Many Calories Our Foods Contain?

September 24th, 2008 | Posted in Weight loss general

We hear many times questions like: how many calories are there in a banana, or in a yogurt, or in a cup of sour cream?

The secret of counting calories lays in knowing what the foods are composed of: carbohydrates, proteins and fat. According to Sadava, David and Orians, Gordon H. Life: The Science of Biology , we can start our calculations from the following facts:

• Fat = 9.5 calories / g
• Carbohydrates = 4.2 calories / g
• Proteins = 4.1calories / g
• Alcohol = 7 calories / g

Knowing that the average human body of an average person needs about 1500 - 2000  calories (1.5 - 2 kcal) for supporting the daily routine activities, you can see for yourself how much you need to eat in order to maintain your actual weight, to lose or gain some pounds, according to your needs. So, losing weight becomes a matter of calculating the daily calories intake, and this is one of the weight loss tips that can secure a healthy slimming.

Calories and Carbohydrates

Carbohydrates, which in chemistry terms are called saccharides, are the food molecules which give us the most energy. Their molecules are very simple and they have an important role in supporting life.

A basic unit of carbohydrate is called by chemists a monosaccharide (CH₂O) such as glucose and fructose. Two combined monosaccharides are known as a disaccharide such as sucrose and lactose. Carbohydrates having between 3 and 6 monosaccharides are named oligosaccharides, while bigger formations are polysaccharides. Some examples of polysaccharides are starch, glycogen and cellulose.

Unlike proteins and fats, carbohydrates are not considered essential nutrients. The body can obtain all its energy by converting fats and proteins.Why then not give up carbs fopr good, and eat only foods based on proteins and fats?

Because fats and proteins are vital building components for tissues and cells, it is not wise to use them for producing energy for the body functions. Carbs and proteins provide the body with about 4 calories per gram while fats supply 9 calories, which is more than double. Put into in SI units, carbs supply  16.7 mega joule of energy for each kilogram. Although it seems like fats provide more calories per gram, it is better to consume carbohydrates for energy production purposes because they are abundantly available in foods like pasta, rice, bread, beans or cereals. They also require less water to be digested.

As you can see, there’s more philosophy behind healthy weight loss, rather than counting pounds, days and calories. This is why nutritionists can help and guide you through the process of getting rid of your extra pounds without suffering from major dis-balances of your body.