Striking a balance

To keep in shape, in every sense of the word, we need to strike a correct balance between intake of food and expenditure of metabolic, physical and intellectual energy. In order to achieve this there are a couple of things we need to know.

Intake

Carbohydrates are the main source of energy in what we eat. Nutritionists recommend that they should account for at least half of our food intake. However, surveys show that this is simply not happening. We consume too great a proportion of lipids and proteins.

And that does nothing for our shape. Studies have proved that the fewer carbohydrates adults consume, the higher their body mass index. In other words, they are more likely to become overweight or obese. So carbohydrates should play a greater role in our diet.

All carbohydrates, including sugar, have the same calorific value: 4 kcal per gram compared with 7 kcal for alcohol and 9 kcal for lipids.
4 kcal is also the calorific “weight” of a gram of protein.

Expenditure

There is one form of energy expenditure that we barely think about: basal metabolism. This is the amount of energy needed to maintain breathing, heartbeats and blood circulation, in other words the normal functioning of the resting body. This alone takes up around 70% of our energy, i.e. 1400 kcal per day. If we add digestion, which accounts for a further 10%, we can see that with no effort at all we use up a lot of energy!

Actual physical activity, walking, running, or even shopping accounts for the remaining 20%. The following chart shows the energy used in various activities.

Calorie burning chart

- One hour sitting 100 kcal
- One hour standing 140 kcal
- One hour doing housework 150-250 kcal
- One hour slow walking (4.8 km/h) 300
- fast walking (5.6 km/h) 360
- cycling (12 km/h) 300
- playing golf 300
- gardening 300
- jogging 600- 750