How long does it take to lose weight & when do you start to notice?

Weight loss doesn’t follow a fixed timeline! Some people notice changes within weeks, while others take longer.

How quickly you lose weight and when you start to see or feel results depends on biology, habits, health, and consistency.

Here, we’ll walk you through realistic weight loss timelines and the early signs that your treatment is starting to work. We’ll also explain why the scales can sometimes be misleading and how to track meaningful progress beyond weight alone.

Key points

• Weight loss timelines vary widely and are influenced by things like metabolism, lifestyle habits, health conditions, and consistency.
• Early progress often happens internally, including improved energy or appetite control, before clear changes can be seen on the scales or in the mirror.
• Tracking non-scale wins, like how clothes fit or improved general health, can help you stay motivated even when weight loss feels slow.

How long does it take to lose weight?

Safe, sustainable weight loss is gradual, typically building over months rather than weeks, and depends on factors like calorie intake, activity levels, and individual metabolism.

The NHS describes sustainable weight loss as around 0.5 to 1 lb (0.25 to 0.5 kg) per week for many adults. Some early weight changes may happen more quickly, often reflecting short-term fluid shifts rather than true fat loss.

What affects the time it takes to lose weight

How quickly you lose weight is influenced by a combination of biological, behavioural, and health-related factors. These factors determine how the body uses energy and responds to changes in eating patterns, activity levels, and daily routines.

Basal metabolic rate (BMR)

Your BMR is the number of calories your body needs to maintain basic functions at rest. It affects how many calories you need to consume daily and varies between individuals based on factors such as age, sex, body composition, and genetics.

Calorie deficit level

The size of a calorie deficit influences how quickly weight loss occurs. Very aggressive deficits may lead to faster short-term loss but can increase fatigue, muscle loss, and difficulty sustaining progress. Moderate deficits support steadier, more sustainable weight loss.

Exercise frequency and intensity

Physical activity supports weight loss by increasing energy use and preserving muscle mass. It’s important to remember that consistency is more important than intensity when it comes to exercise; regular movement and a balance of cardio and strength training will help contribute to long-term weight loss.

Age

Metabolic rate can change with age due to shifts in muscle mass and hormone levels. As a result, weight loss may happen more slowly over time, so having realistic expectations and developing sustainable habits is important.

Sleep and stress levels

Sleep and stress affect hormones that regulate appetite and fat storage. Poor sleep or ongoing stress can increase hunger, reduce energy levels, and make weight loss more difficult despite consistent efforts.

Medical conditions

Some medical conditions and medications can affect metabolism, appetite, or energy levels. Hormonal conditions or long-term treatments may influence the speed of weight loss, which is why personalised, medically supported care can be helpful for some people.

How long does it usually take to notice weight loss results?

Many people start to notice weight loss within a few weeks, but this varies.

The scales may not reflect fat loss straight away. In the early stages, the body can be changing even if your weight doesn’t change much. Some people notice changes in how they feel, such as higher energy or improved fitness levels, before they see visible changes.

What are the different ways you can measure weight loss

Weight loss can be measured in several ways, and using multiple methods gives you a clearer picture of progress. Scale weight is only one marker of weight loss and does not always reflect changes in body composition or health.

Body weight changes

Tracking body weight over time can help identify trends, but daily weight fluctuations are normal. Changes in hydration, digestion, and hormones can cause short-term shifts that do not reflect true fat loss, so weekly averages are often more meaningful than daily measurements.

Dress and clothes size changes

Changes in how clothes fit are a common early sign of fat loss. Looser waistbands or improved comfort can indicate reductions in body fat even when the number on the scales has not changed significantly.

Changes in physical appearance

Visible changes in body shape often happen gradually. Weight loss may first show in areas such as the face, waist, or hips, but this differs between individuals based on genetics and fat distribution.

Energy levels

Improved energy levels are a common early result of healthier eating and increased physical activity. Feeling less fatigued or more capable during daily tasks can be a meaningful sign that positive changes are taking place.

Blood pressure levels

Weight loss can be associated with improvements in blood pressure over time. These changes may occur before visible weight loss and are an important indicator of improved cardiovascular health.

How to track your weight loss

Tracking weight loss works best when you use more than one method. Weight alone does not tell the whole story, so combining what you see on the scales with other changes in your body and lifestyle can help you understand progress and stay motivated over time.

Using multiple tracking tools also helps reduce frustration during periods where weight loss slows or fluctuates, as healthy changes may still be happening.

Take photos

Progress photos can help you spot physical changes that are easy to miss day-to-day. Taking photos every 2 to 4 weeks, in similar lighting and clothing, makes it easier to compare changes in body shape over time.

Photos are particularly useful when scale weight stays the same, but your body composition is changing.

Journaling

Journaling allows you to record eating habits, activity levels, sleep, mood, and challenges alongside weight changes. This can help identify patterns, triggers, and behaviours that support or hinder progress.

Writing things down can also improve awareness and motivation, even when results feel slow.

Track other achievements besides weight loss

Non-scale achievements reflect progress that the scales cannot show. These may include improved fitness, greater consistency with healthy habits, better confidence, or improved wellbeing.

Recognising these changes can help maintain motivation and reinforce long-term behaviour change, especially during weight plateaus.

One thing I always remind my patients is that the scales only tell part of the story. If you're sleeping better, feeling more energised, or noticing your clothes fit differently, those are real signs of progress. Weight loss isn't always a straight line, and that's completely normal — what matters most is that you're building healthier habits you can stick with long-term.

Ayesha Bashir, myBMI weight loss expert

Frequently asked questions

How long does it take to lose weight?

Most people lose weight gradually over weeks and months rather than days. Sustainable weight loss depends on consistency, calorie balance, activity levels, and individual biology, so timelines vary.

Why am I not losing weight even though I am trying?

Weight loss can stall even when effort feels high due to factors such as hidden calories, reduced metabolism, stress, poor sleep, or medical conditions.

Is faster weight loss better?

Faster weight loss is not always better, and it can be harder to maintain. Rapid loss may increase fatigue, muscle loss, and the risk of regaining the weight lost.

How much weight loss is realistic per week?

For many adults, a realistic and sustainable rate of weight loss is around 0.25 to 0.5 kg (0.5 to 1 lb) per week, though this can vary.

Can medication change how quickly I lose weight?

Yes. Some medications, including weight-loss treatments, can affect appetite, metabolism, or how the body uses energy, which may change the rate of weight loss.

Why does weight loss slow down over time?

Weight loss often slows as the body adapts to a lower weight and reduced calorie intake. Changes in metabolism and energy needs mean progress may become less noticeable. This is normal and does not mean weight loss has failed or stopped permanently.

Sources

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• Metabolic Consequences of Weight Reduction. (2023) National Library of Medicine [accessed 29 January 2026]
• Tips to help you lose weight. (2023) NHS [accessed 26 January 2026]
• Weight Fluctuations. (2020) NHS [accessed 26 January 2026]
• Drugs That Affect Body Weight, Body Fat Distribution, and Metabolism. (2019) National Library of Medicine [accessed 26 January 2026]
• Metabolic changes in aging humans: current evidence and therapeutic strategies. (2022) National Library of Medicine [accessed 26 January 2026]
• Sleep Deprivation: Effects on Weight Loss and Weight Loss Maintenance. (2022) National Library of Medicine [accessed 26 January 2026]
• Effect of weight loss on blood pressure changes in overweight patients: A systematic review and meta‐analysis. (2023) National Library of Medicine [accessed 26 January 2026]
• Metabolic Consequences of Weight Reduction. (2023) National Library of Medicine [accessed 26 January 2026]
• Risks Associated With Excessive Weight Loss. (2024) National Library of Medicine [accessed 26 January 2026]