How much weight could I lose in a month if I stop eating bread, pasta, and rice, reduce sugar, weight train, and do 10,000 steps a day, while taking 125mcg of levothyroxine (thyroid hormone replacement) after a full thyroidectomy?

Weight Loss Expectations with Your Proposed Plan

With your current parameters (27F, 164cm, 95kg, BMI 35.3) and proposed lifestyle changes, you can realistically expect to lose approximately 2-4 kg (4.4-8.8 lbs) in the first month, with the understanding that your thyroid replacement status should not significantly impair weight loss if your TSH is adequately controlled. 1

Understanding Your Baseline Energy Needs

Your estimated total daily energy expenditure is approximately 2,200-2,400 calories per day given your age, height, weight, and planned activity level (10,000 steps plus weight training). 2

• Target caloric intake for women: 1,200-1,500 kcal/day creates the necessary 500-750 kcal/day deficit for effective weight loss 1
• Expected rate: A 500 kcal daily deficit typically produces approximately 0.45 kg (1 lb) per week, while a 750 kcal deficit produces closer to 0.7 kg (1.5 lbs) per week 2

Impact of Your Specific Dietary Changes

Eliminating bread, pasta, rice, and reducing sugar will likely create a substantial caloric deficit, but the key is ensuring you're actually achieving 1,200-1,500 kcal/day total intake:

• Carbohydrate restriction alone doesn't guarantee weight loss unless it creates the necessary energy deficit 1
• Your approach is sound because these foods are typically calorie-dense, and their elimination naturally reduces total intake 1
• Critical caveat: You must replace these foods with nutrient-dense options (vegetables, lean proteins, legumes, whole grains in moderation) rather than simply eating less, to avoid nutritional deficiencies 1

Physical Activity Contribution

Your planned activity (weight training + 10,000 steps daily) is excellent for weight loss and maintenance:

• Physical activity alone typically produces only 1-3 kg weight loss, but is additive to dietary restriction 3
• 10,000 steps daily plus weight training likely provides 150-200 minutes/week of moderate-intensity activity, which aligns with guideline recommendations 1
• Resistance training 2-3 times per week is crucial for preserving lean muscle mass during weight loss, preventing the metabolic slowdown that often accompanies caloric restriction 4

Thyroid Replacement Considerations

Your 125mcg levothyroxine dose after total thyroidectomy should not be a barrier to weight loss if properly managed:

• Adequate thyroid replacement means you should have similar metabolic capacity as someone with a functioning thyroid 5, 6
• Important: Ensure your TSH is in the target range (typically 0.45-4.5 mIU/L, though some patients feel better with mildly suppressed TSH around 0.8-2.0 mIU/L) 5, 6
• Weight-based dosing consideration: At 95kg, some patients require dose adjustments during significant weight loss; your dose may need reduction as you lose weight 5
• Common pitfall: If you feel fatigued or have difficulty losing weight despite adherence, check your TSH levels as your current dose may be inadequate or excessive 6

Realistic First Month Expectations

Week 1-2: Expect 1.5-3 kg loss (much of this is water weight from glycogen depletion due to carbohydrate restriction) 1

Week 3-4: Expect 0.5-1 kg per week (true fat loss) 2

Total first month: 2-4 kg (4.4-8.8 lbs) is realistic and healthy 1

Critical Success Factors

Self-monitoring is essential for success:

• Track food intake daily (apps or food diary) 1, 4
• Weigh yourself weekly (same day, same time, same conditions) 1
• Monitor physical activity to ensure you're meeting your 10,000 step goal 1

Common pitfalls to avoid:

• Underestimating caloric intake is extremely common; people typically underestimate by 30-50% 7
• Overestimating activity expenditure is equally common 7
• Liquid calories (juices, alcohol, sweetened beverages) can sabotage your deficit—eliminate these entirely 1
• Inadequate protein intake (aim for at least 1.0 g/kg body weight = 95g daily) helps preserve muscle mass and increases satiety 1

Beyond the First Month

Months 2-6: With continued adherence, comprehensive lifestyle interventions typically produce 5-10% total body weight loss (4.75-9.5 kg for you) by 6 months 1

Metabolic adaptation warning: Your body will adapt to weight loss by reducing energy expenditure and increasing hunger hormones, making continued loss progressively harder 7

Maintenance phase: After achieving initial weight loss, increase physical activity to 200-300 minutes/week to prevent regain 1, 4

When to Seek Additional Support

Consider intensifying your approach if you achieve less than 2 kg loss in the first month despite adherence:

• Consult with a registered dietitian for structured meal planning 1
• Verify your thyroid function is optimized 5
• Consider whether medications or other medical conditions are interfering 4