Can sleep and stress really affect my weight?

Of all the factors that influence weight, sleep is one of the most consistently underestimated. Sleep directly affects two key hormones involved in appetite: leptin, which helps signal fullness, and ghrelin, which signals hunger.

When sleep is short or poor quality, leptin tends to fall and ghrelin tends to rise. In other words, you feel hungrier and less satisfied, even if you're eating exactly the same. That isn't a willpower problem. It's a measurable change in your body that makes healthy eating harder.

Stress affects much more than our mood. Ongoing stress influences hormones, sleep, cravings and the energy we have to plan and prepare food. When life feels overwhelming, healthy eating is often the first thing to slip. Learning to manage stress isn't a luxury; it's part of managing weight.

It's not only hormones. When we're tired, the parts of the brain involved in planning and self-control work less effectively, while we become more drawn to high-energy, rewarding foods. Add in less energy to cook, less motivation to be active, and more time awake to eat, and it's easy to see how poor sleep can quietly undermine even the best intentions.

Improving sleep is one of the most underrated steps you can take, and the programme includes practical, achievable strategies to help.

You might find Week 11 especially useful if you:

• Regularly get less sleep than you need, or wake feeling unrefreshed
• Notice you snack more after a poor night's sleep
• Feel under constant pressure at work or at home
• Spend most of your day sitting
• Feel that exercise "isn't for you"

Improving your sleep doesn't have to mean a complete overhaul of your evenings. Often, a few small adjustments to your routine, your bedroom environment, or your habits during the day can make a noticeable difference to how well you sleep, and how hungry you feel the next day.

In Week 11, you'll learn practical, evidence-based strategies to help you sleep better, along with ways to notice the link between your sleep and your eating patterns.

Physical activity is good for health at every size, whether or not it changes the number on the scales. But exercise is only part of the picture. The everyday movement we do without thinking about it, walking to the shops, doing housework, taking the stairs, can make a surprising difference to the energy we use each day.

Equally, many of us spend long hours sitting, at desks, in cars and on sofas. Understanding how this affects your health, and finding easy ways to break it up, can be just as valuable as a workout.

Many people feel put off physical activity because of past experiences, worries about being judged, or a belief that exercise has to be intense to be worthwhile. In fact, regular movement brings significant benefits for heart health, mood, sleep, blood sugar and joint health, whatever your weight, and whether or not it changes the number on the scales.

The programme focuses on finding forms of movement that work for your body and your life, rather than pushing you towards anything that feels unrealistic.

Sleep, stress, activity and eating are closely linked. Poor sleep increases stress, stress affects eating, eating affects energy, and energy affects activity. The encouraging part is that this works in the other direction too: improving one area often makes the others easier. This course helps you see the bigger picture, and choose where to start.

Stress management advice often sounds great in theory but feels impossible in practice. Long bubble baths and weekend retreats aren't realistic for most people juggling work, family and everything else.

The course focuses on simple stress management techniques that can be used in a few minutes, at home, at work, or on the go. They're designed to help you feel calmer and more in control, and to reduce the likelihood that stress will lead you towards food.

Many of us spend most of our waking hours sitting down: at a desk, in the car, on the sofa in the evening. Long periods of sitting have been linked with poorer health, even in people who exercise regularly, and UK guidelines recommend breaking up long periods of inactivity where possible.

The good news is that small, regular changes can make a difference. Standing up during phone calls, taking short walking breaks, or rethinking how you spend your evenings can all help.

The final session of Week 11 looks at practical ways to reduce sitting time that fit around work and family life, without needing any special equipment or extra time in your day.

Much of the energy we use each day doesn't come from exercise at all, but from everyday movement: standing, walking, fidgeting, gardening, cleaning and carrying the shopping. This is sometimes called non-exercise activity, and it can vary hugely between people and between days.

The encouraging part is that small increases in everyday movement can add up to a meaningful difference over time, without needing to set aside time for formal exercise. You'll learn how to make the most of it in Week 11.

Lifestyle Factors Affecting Weight is one of 12 weekly courses in the Raiys Weight Management Programme. Each course is broken down into short sessions of around five minutes, one for each day of the week, so you can fit them around work, family and everything else. Each session ends with a short reflection, something to think about, and a simple action, something to try that day.

You can work through the programme in order, building each week on the last, or, if lifestyle factors affecting weight is the area you most want to work on, you can go straight to it. Either way, the sessions are designed to be used alongside the BeChange app, which helps you put what you learn into practice in everyday life.

In Week 11 of the programme, you'll learn:

• How sleep affects appetite and weight
• Practical strategies to improve your sleep
• How stress and cortisol affect your body and eating
• Stress management techniques you can use every day
• How physical activity supports health at any size
• The power of everyday movement, and how to reduce sitting time

Do I need to join a gym?

Not at all. The course focuses on activity that fits your life, including everyday movement that doesn't feel like exercise.

What if my sleep problems are medical?

If you have ongoing sleep problems, such as loud snoring or feeling exhausted despite sleeping, please speak to your GP.

How much activity should I do?

The course covers the current UK recommendations and helps you build up gradually from wherever you're starting.

Why does stress make me want to eat?

Stress affects hormones, energy and mood, and it often leaves us looking for quick comfort. It can also make it harder to plan and prepare food. Week 11 explains these links in more detail and offers practical ways to manage stress so that it has less influence over what you eat.

I'm already very busy. Can I fit this in?

Yes. The lifestyle changes in this course are designed to be small and realistic, so they fit around existing commitments rather than adding to them. Even a few minutes here and there can make a difference over time.

The Raiys Weight Management Programme is a 12-week, clinician-led digital programme designed to be used alongside the BeChange app. Each week focuses on one course, broken into short five-minute daily sessions, each with a reflection and a simple action to take into your day. It's built on current NICE and SIGN guidance and on proven behaviour-change approaches, and it's written to support you, never to judge you.

This article is for general information only and is not a substitute for personal medical advice. If you have a health condition, take regular medication, are pregnant, or have concerns about your weight or eating, please speak to your GP or healthcare professional before making significant changes. If you have had, or are preparing for, weight loss surgery, please follow the advice of your specialist team.

Dr Laura Coia is a GP Partner in NHS Scotland with over 25 years of clinical experience, and Co-founder and Medical Director of Raiys Digital Health.

Dr Izzy Howat is a Consultant Endocrinologist and NHS Weight Management Specialist, and Weight Management Lead at Raiys Digital Health. She is the author of the Raiys Weight Management Programme.

• National Institute for Health and Care Excellence (NICE) (2025). Overweight and obesity management (NG246). London: NICE. (Replaces CG189.)
• Scottish Intercollegiate Guidelines Network (SIGN) (2010). Management of obesity (SIGN 115). Edinburgh: SIGN. (Some recommendations may since have been superseded; read alongside NICE NG246.)
• UK Chief Medical Officers (2019). UK Chief Medical Officers' Physical Activity Guidelines.
• NHS. How to get to sleep; and sleep guidance. nhs.uk
• Spiegel K, Tasali E, Penev P, Van Cauter E. (2004). Sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Annals of Internal Medicine, 141(11), 846–850.
• Taheri S, Lin L, Austin D, Young T, Mignot E. (2004). Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index. PLoS Medicine, 1(3), e62.
• Cognitive behavioural therapy (CBT) evidence base for weight-related thinking patterns, consistent with NICE's approach to individual behaviour change (PH49).
• British Obesity & Metabolic Surgery Society (BOMSS). Clinical guidance for patients undergoing bariatric surgery. Relevant only to readers who have had, or are preparing for, weight loss surgery; this programme is a non-surgical behavioural programme.