Why do we put on weight?

As a rule, weight loss is caused by an imbalance between your calorie intake and the calories your body uses up. It's quite simple: if you eat what you don't burn, you put on weight! The causes of weight gain aren't always to be found in your diet, though. There are other factors that come into play:









Factors that predispose us to weight gain:

• Family history:  A tendency to gain weight is hereditary. A child has a 15% risk of being obese if neither parent is overweight, a 40% risk if one parent is overweight, and an 80% risk if both parents are overweight.  
• Endorcine disorders: Certain hormonal problems (an overactive thyroid, hypercortisolism or Crushing's Syndrome) can have an effect on weight gain. These conditions require medical care and special treatment.  
• A sedentary lifestyle: Inactivity contributes to weight gain. The less exercise you get, the more energy you burn, and the harder it is to maintain a stable weight.  
• Bad eating habits: Eating too much unhealthy food obviously makes you fat. There are so many errors in this category, and most of the time a combination of these is to blame: eating too much calorific, rich, fatty and sugary food, cooking your food in too much fat, overeating, not knowing when you're full or hungry, and unstructured eating (skipping meals, eating on the hoof too quickly, snacking, eating too much or too little at the wrong time of day, poor knowledge of a balanced diet, etc etc).
• Some types of medication: Certain drugs (anti-depressives, female hormones and cortisone) are proven to make you gain weight, while others stop you from losing weight.

Factors that trigger weight gain

• Events and stages in a woman's life: Hormonal change, puberty, pregnancy and the menopause all contribute to weight gain in women.  
• Changes in lifestyle: Stopping or changing jobs, retirement, moving, the death of a loved one, moving in with a partner, having kids...all of these can influence your mood, lifestyle and eating patterns, and lead to (sometimes significant) weight gain.  
• Giving up smoking: Quitting reduces the amount of calories you burn at rest, increases your appetite, makes you want to eat sugary foods to compensate for the lack of nicotine and to give you something to do with your hands. It's got to be done, but stopping often means piling on a few pounds (sometimes a lot).   
• Giving up exercise: Going from an active to a sedentary lifestyle causes loss of muscle mass, slowing down of the metabolism and reduction of calorie burning, which can be disastrous if you don't adjust your diet accordingly.  
• Stress and overwork: There's nothing like eating calorific food to make up for fatigue and anxiety: through various hormone mechanisms, they give you a feeling of wellbeing. And we all know too much sugary, fatty food leads to weight gain.   
• Alternating day and night working hours: It's hard to eat a healthy, regular diet when you don't keep the same hours as other people. One study of nurses, for example, concluded that night nurses are twice as likely to gain 5 kilos after 10 years in the job than day nurses.

Factors that make it worse
Alternating periods of excess and strict dieting is otherwise known as the yo-yo effect. The more diets you impose on your body, the more resistant it becomes to restrictions, and the more efficient your body becomes at storing fat every time you binge. Every time you start eating normally again after a period of guilt-imposed starvation, you put on more weight and actually end up heavier than before. It's not worth it!