Causes of Feet Swelling: What You Need to Know

If you’ve ever noticed your shoes digging in uncomfortably by lunchtime, you know how frustrating fluid buildup can be.

Sometimes swollen feet are temporary, but swelling can also have an underlying medical cause. If it persists, keeps coming back or appears suddenly, it’s worth getting medical advice rather than assuming it’s simply down to standing, heat or uncomfortable shoes.

This one I know from the inside, not just from research. Chronic swelling has been part of my life alongside the arthritis and joint replacements for years now, so I’ve spent a lot of time working out what genuinely helps and what’s just noise. I’m not a clinician, but I do know what it’s like to live with feet that don’t always cooperate.

What Is Oedema?

Oedema is swelling caused by a build-up of fluid in the body’s tissues. In the feet and lower legs, you may notice puffiness around the ankles or feet, skin that looks stretched or shiny, stiffness or discomfort, or dents left in the skin when you press it.

There are lots of possible causes. Sometimes it’s something fairly straightforward, such as sitting or standing in the same position for too long, but swelling can also be linked to medication, an injury or an underlying health condition. That’s why new, unexplained or persistent swelling shouldn’t simply be put down to your shoes.

Looking for a bigger picture view of foot pain? You’ll find it in our Complete Guide to Foot Pain Relief — a practical overview that covers every cause from heel to toe and how to ease it fast.

Common Causes of Feet Swelling

There are lots of possible reasons for swollen feet and ankles. Some are temporary, while others may need medical investigation.

Common causes include:

• Sitting or standing in the same position for a long time
• Eating a lot of salty food
• Being overweight
• Pregnancy
• Certain medicines, including some blood pressure medicines, antidepressants, steroids, contraceptive pills and hormone therapy
• Varicose veins
• An injury such as a sprain or strain
• An infection
• Thyroid problems
• Problems affecting the heart, kidneys or liver
• A blood clot
• Lymphoedema

If you don’t know what’s causing the swelling, particularly if it’s new or only affecting one leg, it’s worth getting medical advice rather than trying to diagnose the cause yourself.

Symptoms of Oedema in the Feet

Oedema in the feet, ankles or legs can cause:

• Swelling or puffiness
• Shiny or stretched-looking skin
• Dents left in the skin when you press it
• Discomfort or stiffness
• Changes in skin colour or dry skin

You may also notice that shoes or socks which normally fit comfortably suddenly feel much tighter.

I recognise every one of these myself. The tight-shoe-marks one especially — it’s usually my first clue that today’s a worse swelling day and I can feel it before I’ve even looked down.

Why the Right Shoes Matter

When your feet swell, shoes that fitted comfortably earlier in the day can suddenly feel tight. Footwear with enough room and some adjustability can help avoid extra pressure and rubbing when your foot size changes.

• A roomy toe box with enough width and depth
• Soft or stretchable uppers
• Adjustable fastenings such as laces or touch-fastening straps
• Comfortable cushioning
• Removable insoles if you need extra room or use orthotics

This is exactly why I’ve had to build my whole approach to footwear around adjustability rather than a single “correct” fit. My feet aren’t the same size two days running, so a shoe that only works when swelling isn’t bad doesn’t work for me at all.

👉 Read more: Best Shoes for Swollen Feet During Pregnancy

Things That May Help Ease Swelling

What helps depends partly on why your feet are swollen, but there are some simple things that may help with mild swelling:

• Raise your legs on a chair or pillows when you can
• Avoid sitting or standing in the same position for long periods
• Get some gentle exercise, such as walking
• Wear wide, comfortable shoes that don’t pinch or rub
• Avoid socks, shoes or clothing that feel too tight
• Keep the skin on your feet clean, dry and moisturised

If the swelling doesn’t improve, gets worse or you don’t know what’s causing it, speak to your GP rather than relying on self-care alone.

For me personally, elevation and compression socks make the biggest difference. Compression was recommended for my own circumstances, though, so I wouldn’t assume that what’s suitable for my swelling is automatically right for someone else’s.

When to Get Medical Help

See your GP if swelling in both feet, ankles or legs hasn’t improved after a few days of looking after it at home, is getting worse, or you already have a condition affecting your heart, kidneys or leg veins.

Get urgent advice from your GP or NHS 111 if:

• One foot, ankle or leg becomes swollen and you don’t know why
• The swelling is severe, painful or starts very suddenly
• A swollen area is red or feels hot
• You have a high temperature or feel hot, cold or shivery
• You have diabetes and your feet, ankles or legs are swollen

Call 999 if swelling is accompanied by symptoms such as shortness of breath or difficulty breathing, a tight, heavy or painful chest, coughing up blood, noticeable heart palpitations, or feeling faint, confused, sick or clammy.

These symptoms can indicate a serious problem that needs immediate medical attention.

Questions on Feet Swelling (Oedema)

Q: Is swelling in the feet always a sign of a medical problem?
A: No. Feet and ankles can swell for relatively simple reasons such as sitting or standing in the same position for a long time. However, persistent, worsening or unexplained swelling should be checked by a healthcare professional.

Q: Why do my feet swell more later in the day?
A: Swelling can become more noticeable after you’ve spent a long time sitting or standing. If it keeps happening, is getting worse or you don’t know what’s causing it, speak to your GP.

Q: Can eating too much salt contribute to swollen feet?
A: It can. Eating too much salty food is one possible cause of oedema. If swelling is persistent or unexplained, though, don’t assume salt is the cause — speak to your GP.

Q: Can swollen feet be related to shoes?
A: Shoes don’t necessarily cause the swelling, but footwear that becomes too tight as your feet swell can add pressure, rubbing and discomfort. A roomier shoe with adjustable fastenings can be much more comfortable when your foot size changes during the day.

Q: Are swollen feet common in pregnancy?
A: Swelling of the feet and ankles is common during pregnancy, particularly later in pregnancy. Sudden or rapidly increasing swelling can sometimes need urgent assessment, especially if you have other symptoms, so don’t assume every change is normal pregnancy swelling.

Q: What’s the difference between oedema and lymphoedema?
A: Oedema is a general term for swelling caused by fluid building up in the tissues. Lymphoedema is swelling caused by a problem with the lymphatic system. If you have persistent swelling and don’t know what’s causing it, it’s worth getting medical advice rather than trying to distinguish between the two yourself.

Q: Can exercise reduce swollen feet?
A: Gentle exercise such as walking can help with some mild swelling by keeping you moving and avoiding long periods in one position. What is appropriate depends on the cause of the swelling, so unexplained or significant swelling should be checked rather than simply exercised away.

Q: Does hot weather make feet swell more?
A: Yes, some people notice more swelling in hot weather. If the swelling is new, severe, only affects one side or doesn’t settle, don’t assume that heat is the only cause.

Q: Can swollen feet be a side effect of medication?
A: Yes. Some medicines can cause swelling as a side effect, including certain blood pressure medicines, antidepressants, steroids and hormone treatments. If you think a medicine may be causing your swelling, speak to your GP or pharmacist rather than stopping it yourself.

Q: Do compression socks really work?
A: Compression socks can help with some causes of leg and foot swelling, but they aren’t suitable for everyone and the correct type and fit matter. If you have unexplained swelling or aren’t sure whether compression is suitable for you, get medical advice first.

Q: Can heart problems cause swollen feet?
A: Yes. Some heart conditions, including heart failure, can cause swelling in the feet, ankles and legs. But swollen feet have many possible causes, so swelling alone doesn’t tell you that you have a heart problem.

Q: Do swollen feet mean kidney disease?
A: Not necessarily. Kidney problems are one possible cause of swelling, but there are many others. Persistent or unexplained swelling should be assessed rather than using it to diagnose the cause yourself.

Q: Do swollen feet always need treatment?
A: Not always. Mild swelling caused by something such as sitting or standing for a long time may settle on its own. Swelling that persists, gets worse, appears suddenly or has no obvious cause should be medically assessed.

Q: Why do my feet swell more on flights?
A: Sitting still for a long journey can contribute to swelling in the feet and ankles. Moving around when you can can help, but sudden or unexplained one-sided swelling, particularly with pain, should be assessed urgently.

📌 Summary
Swollen feet and ankles can have many causes, from sitting or standing for long periods to medication or an underlying health condition. Comfortable, adjustable footwear can make swollen feet easier to accommodate, but it doesn’t treat the cause of oedema. If swelling is persistent, worsening, unexplained or comes with any of the warning signs above, get medical advice.

Medical disclaimer: This article is for general information and isn’t a substitute for medical advice. If you have new, unexplained or persistent swelling in your feet or legs, speak to your GP. Seek urgent medical help for the warning signs described above.

About Sue Holland
Sue writes WiderFittingShoes.com from first-hand experience of finding footwear for wide and difficult-to-fit feet. After two hip replacements, two ankle replacements and years of dealing with arthritis, swelling and feet that don’t always behave the same from one day to the next, she shares the practical things she’s learned about shoe fit, width and comfort.

If you’ve ever noticed your shoes digging in uncomfortably by lunchtime, you know how frustrating fluid buildup can be.

Sometimes swollen feet are temporary, but swelling can also have an underlying medical cause. If it persists, keeps coming back or appears suddenly, it’s worth getting medical advice rather than assuming it’s simply down to standing, heat or uncomfortable shoes.

This one I know from the inside, not just from research. Chronic swelling has been part of my life alongside the arthritis and joint replacements for years now, so I’ve spent a lot of time working out what genuinely helps and what’s just noise. I’m not a clinician, but I do know what it’s like to live with feet that don’t always cooperate.

What Is Oedema?

Oedema is swelling caused by a build-up of fluid in the body’s tissues. In the feet and lower legs, you may notice puffiness around the ankles or feet, skin that looks stretched or shiny, stiffness or discomfort, or dents left in the skin when you press it.

There are lots of possible causes. Sometimes it’s something fairly straightforward, such as sitting or standing in the same position for too long, but swelling can also be linked to medication, an injury or an underlying health condition. That’s why new, unexplained or persistent swelling shouldn’t simply be put down to your shoes.

Looking for a bigger picture view of foot pain? You’ll find it in our Complete Guide to Foot Pain Relief — a practical overview that covers every cause from heel to toe and how to ease it fast.

Common Causes of Feet Swelling

There are lots of possible reasons for swollen feet and ankles. Some are temporary, while others may need medical investigation.

Common causes include:

• Sitting or standing in the same position for a long time
• Eating a lot of salty food
• Being overweight
• Pregnancy
• Certain medicines, including some blood pressure medicines, antidepressants, steroids, contraceptive pills and hormone therapy
• Varicose veins
• An injury such as a sprain or strain
• An infection
• Thyroid problems
• Problems affecting the heart, kidneys or liver
• A blood clot
• Lymphoedema

If you don’t know what’s causing the swelling, particularly if it’s new or only affecting one leg, it’s worth getting medical advice rather than trying to diagnose the cause yourself.

Symptoms of Oedema in the Feet

Oedema in the feet, ankles or legs can cause:

• Swelling or puffiness
• Shiny or stretched-looking skin
• Dents left in the skin when you press it
• Discomfort or stiffness
• Changes in skin colour or dry skin

You may also notice that shoes or socks which normally fit comfortably suddenly feel much tighter.

I recognise every one of these myself. The tight-shoe-marks one especially — it’s usually my first clue that today’s a worse swelling day and I can feel it before I’ve even looked down.

Why the Right Shoes Matter

When your feet swell, shoes that fitted comfortably earlier in the day can suddenly feel tight. Footwear with enough room and some adjustability can help avoid extra pressure and rubbing when your foot size changes.

• A roomy toe box with enough width and depth
• Soft or stretchable uppers
• Adjustable fastenings such as laces or touch-fastening straps
• Comfortable cushioning
• Removable insoles if you need extra room or use orthotics

This is exactly why I’ve had to build my whole approach to footwear around adjustability rather than a single “correct” fit. My feet aren’t the same size two days running, so a shoe that only works when swelling isn’t bad doesn’t work for me at all.

👉 Read more: Best Shoes for Swollen Feet During Pregnancy

Things That May Help Ease Swelling

What helps depends partly on why your feet are swollen, but there are some simple things that may help with mild swelling:

• Raise your legs on a chair or pillows when you can
• Avoid sitting or standing in the same position for long periods
• Get some gentle exercise, such as walking
• Wear wide, comfortable shoes that don’t pinch or rub
• Avoid socks, shoes or clothing that feel too tight
• Keep the skin on your feet clean, dry and moisturised

If the swelling doesn’t improve, gets worse or you don’t know what’s causing it, speak to your GP rather than relying on self-care alone.

For me personally, elevation and compression socks make the biggest difference. Compression was recommended for my own circumstances, though, so I wouldn’t assume that what’s suitable for my swelling is automatically right for someone else’s.

When to Get Medical Help

See your GP if swelling in both feet, ankles or legs hasn’t improved after a few days of looking after it at home, is getting worse, or you already have a condition affecting your heart, kidneys or leg veins.

Get urgent advice from your GP or NHS 111 if:

• One foot, ankle or leg becomes swollen and you don’t know why
• The swelling is severe, painful or starts very suddenly
• A swollen area is red or feels hot
• You have a high temperature or feel hot, cold or shivery
• You have diabetes and your feet, ankles or legs are swollen

Call 999 if swelling is accompanied by symptoms such as shortness of breath or difficulty breathing, a tight, heavy or painful chest, coughing up blood, noticeable heart palpitations, or feeling faint, confused, sick or clammy.

These symptoms can indicate a serious problem that needs immediate medical attention.

Questions on Feet Swelling (Oedema)

Q: Is swelling in the feet always a sign of a medical problem?
A: No. Feet and ankles can swell for relatively simple reasons such as sitting or standing in the same position for a long time. However, persistent, worsening or unexplained swelling should be checked by a healthcare professional.

Q: Why do my feet swell more later in the day?
A: Swelling can become more noticeable after you’ve spent a long time sitting or standing. If it keeps happening, is getting worse or you don’t know what’s causing it, speak to your GP.

Q: Can eating too much salt contribute to swollen feet?
A: It can. Eating too much salty food is one possible cause of oedema. If swelling is persistent or unexplained, though, don’t assume salt is the cause — speak to your GP.

Q: Can swollen feet be related to shoes?
A: Shoes don’t necessarily cause the swelling, but footwear that becomes too tight as your feet swell can add pressure, rubbing and discomfort. A roomier shoe with adjustable fastenings can be much more comfortable when your foot size changes during the day.

Q: Are swollen feet common in pregnancy?
A: Swelling of the feet and ankles is common during pregnancy, particularly later in pregnancy. Sudden or rapidly increasing swelling can sometimes need urgent assessment, especially if you have other symptoms, so don’t assume every change is normal pregnancy swelling.

Q: What’s the difference between oedema and lymphoedema?
A: Oedema is a general term for swelling caused by fluid building up in the tissues. Lymphoedema is swelling caused by a problem with the lymphatic system. If you have persistent swelling and don’t know what’s causing it, it’s worth getting medical advice rather than trying to distinguish between the two yourself.

Q: Can exercise reduce swollen feet?
A: Gentle exercise such as walking can help with some mild swelling by keeping you moving and avoiding long periods in one position. What is appropriate depends on the cause of the swelling, so unexplained or significant swelling should be checked rather than simply exercised away.

Q: Does hot weather make feet swell more?
A: Yes, some people notice more swelling in hot weather. If the swelling is new, severe, only affects one side or doesn’t settle, don’t assume that heat is the only cause.

Q: Can swollen feet be a side effect of medication?
A: Yes. Some medicines can cause swelling as a side effect, including certain blood pressure medicines, antidepressants, steroids and hormone treatments. If you think a medicine may be causing your swelling, speak to your GP or pharmacist rather than stopping it yourself.

Q: Do compression socks really work?
A: Compression socks can help with some causes of leg and foot swelling, but they aren’t suitable for everyone and the correct type and fit matter. If you have unexplained swelling or aren’t sure whether compression is suitable for you, get medical advice first.

Q: Can heart problems cause swollen feet?
A: Yes. Some heart conditions, including heart failure, can cause swelling in the feet, ankles and legs. But swollen feet have many possible causes, so swelling alone doesn’t tell you that you have a heart problem.

Q: Do swollen feet mean kidney disease?
A: Not necessarily. Kidney problems are one possible cause of swelling, but there are many others. Persistent or unexplained swelling should be assessed rather than using it to diagnose the cause yourself.

Q: Do swollen feet always need treatment?
A: Not always. Mild swelling caused by something such as sitting or standing for a long time may settle on its own. Swelling that persists, gets worse, appears suddenly or has no obvious cause should be medically assessed.

Q: Why do my feet swell more on flights?
A: Sitting still for a long journey can contribute to swelling in the feet and ankles. Moving around when you can can help, but sudden or unexplained one-sided swelling, particularly with pain, should be assessed urgently.

📌 Summary
Swollen feet and ankles can have many causes, from sitting or standing for long periods to medication or an underlying health condition. Comfortable, adjustable footwear can make swollen feet easier to accommodate, but it doesn’t treat the cause of oedema. If swelling is persistent, worsening, unexplained or comes with any of the warning signs above, get medical advice.

Medical disclaimer: This article is for general information and isn’t a substitute for medical advice. If you have new, unexplained or persistent swelling in your feet or legs, speak to your GP. Seek urgent medical help for the warning signs described above.

About Sue Holland
Sue writes WiderFittingShoes.com from first-hand experience of finding footwear for wide and difficult-to-fit feet. After two hip replacements, two ankle replacements and years of dealing with arthritis, swelling and feet that don’t always behave the same from one day to the next, she shares the practical things she’s learned about shoe fit, width and comfort.

Sources and Further Reading

NHS – Oedema