The Effect of a High Protein Diet Versus a Low Fat Diet on Body Weight After Smoking Cessation

The Effect of a High Protein Diet Versus a Low Fat Diet on Body Weight and Composition, Total Energy Expenditure, Metabolic Risk Factors and Eating Behavior After Smoking Cessation

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01069458

Enrollment

122

Registered

2010-02-17

Start date

2010-01-31

Completion date

2013-08-31

Last updated

2017-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Obesity, Overweight, Smoking

Keywords

Dietary intervention, Smoking cessation, Body weight

Brief summary

The purpose of this study is to determine whether subjects following a high protein diet will gain less in weight after smoking cessation compared to subjects following a low fat diet due to the effects of protein on metabolic rate and hunger.

Detailed description

Sustained smoking cessation is one of the most effective therapies to avoid premature morbidity and mortality. However, weight gain associated with nicotine withdrawal may attenuate some of the beneficial health effects and is cited as a major obstacle to quit smoking. The mechanism for the weight gain is not elucidated but reduced resting metabolic rate, reduced total energy expenditure, increased caloric intake and changes in fat metabolism may be involved. Elucidating effective strategies to prevent or reduce post-cessation weight gain may improve health outcomes of smoking cessation.

Interventions

OTHERThe high protein diet group and the low fat diet group

The High Protein Diet Group was advised to have 25 energy percent from protein, 55 energy percent from fat, 20 energy percent from carbohydrate in the diet and the Low Fat Diet Group was advised to have 30 energy percent from fat, 20 energy percent from protein, 50 energy percent from carbohydrate in the diet.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

20 Years to 65 Years

Healthy volunteers

Yes

Inclusion criteria

* Smoking 10 cigarettes per day, BMI 25-40

Exclusion criteria

* Recent change in weight, contra-indications to use varenicline, a medication to assist smoking cessation

Design outcomes

Primary

Measure	Time frame
Body weight and waist circumference	4 weeks, 3 months and 6 months after smoking cessation

Secondary

Measure	Time frame
Resting metabolic rate, total energy expenditure, body composition, components of metabolic syndrome, eating behavior	4 weeks

Countries

Norway

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 11, 2026