How is smoking and weight loss related

Smoking, or nicotine, causes increased dopamine and serotonin release. Both neurotransmitters act as appetite suppressants (especially for sweets), so that on the one hand smokers tend to consume fewer calories than non-smokers. On the other hand, nicotine also increases the basal metabolic rate, i.e. smokers burn 4-16% more calories than non-smokers. Smokers, for example, have an average body weight of 3 - 5% lower than that of non-smokers.

But there are also, and increasingly, overweight smokers. Overweight smokers make fewer attempts to quit and have more relapses. They also tend to gain more weight when they quit smoking. Heavy smokers have an unfavorable fat distribution, namely increased visceral fat, or the so-called "apple shape".

COPD patients are often undernourished and malnourished, up to so-called "pulmonary cachexia". In their case, weight gain is even desirable.

Quitting smoking and gaining weight

The majority of people who quit smoking gain weight, averaging 4 to 5 kg (4.7 kg). However, the range of weight gain is wide:

• 16% decrease
• 37% gain weight less than 5 kg
• 34% gain 5-10 kg
• 13% gain weight more than 10 kg

Weight gain occurs after the acute phase of smoking cessation, i.e. after 2-4 weeks.

The ex-smoker would have to gain over 50 kilos to create a health risk comparable to cigarette smoking.

The reasons are, on the one hand, that the need for calories decreases after quitting smoking (see above), on the other hand, increased appetite is one of the nicotine withdrawal symptoms. Most of the weight gain (69%) can be explained by an increased calorie intake.

Gender specific weight gain

Women smoke more than men to control their weight and are more likely to say they would not tolerate weight gain after quitting smoking. This is probably one of the reasons why women try to quit smoking less often. On average, women gain more weight than men.

There are several ways to counteract weight gain:

  • reduce calorie intake;
  • burn more calories, i.e. increased exercise and sport;
  • Using medication to quit smoking: Medications containing nicotine (especially chewing gum 4 mg and lozenge and sublingual tablets (microtab) 2 mg) seem to be effective in delaying weight gain after quitting smoking if they are used in sufficiently high doses. Bupropion (Zyban®) also delays weight gain after quitting smoking. After stopping these medications, however, ex-smokers gain on average the same weight that they would have gained without medication.
  • Nutritional advice, coaching, behavior therapy.

The potential for weight gain should not be a reason to continue smoking, as the risks of smoking far outweigh the risks of being slightly overweight. The fear of gaining weight is often worse than actually gaining weight.

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