Why Do My Feet Swell In The Heat?

Posted 2 Oct

Love the idea of a vacation somewhere warm and beautiful, but hate the reality of your feet swelling after walking, standing or sitting? Swollen feet and ankles can quickly dampen any holiday, leave you struggling to find shoes that fit, and diminish your comfort and experience when travelling.

Knowing what causes and contributes to why your feet and ankles swell in the heat goes a long way to preventing it. Here’s everything you need to know about heat oedema, known as heat-related foot and leg swelling.

What causes foot swelling in hot weather? Is it your blood vessels?

It’s the heat from your environment that leads to a fluid buildup. Heat can cause blood vessels to expand (dilate), which is actually your body’s natural cooling device, helping you regulate your temperature so you don’t overheat. When blood vessels expand, they allow more blood flow close to the skin, helping heat escape from the body. Unfortunately, this expansion can also leak fluid into the surrounding tissues, causing your feet, ankles, and sometimes even your legs (usually the lower legs) to swell.

Long periods of sitting or standing, like catching flights or after a day of sightseeing or hot baths, can worsen the swelling. Gravity pulls fluid downwards, and in hot weather, your body’s usual mechanisms for moving fluid back up to the heart can slow down. And just like that? Your swelling starts or worsens.

Is there anything you can do to prevent swelling during your trip?

Yes! Even if you’re going to be surrounded by non-stop hot weather and humidity, there are several things you can do to help prevent foot and leg swelling or reduce its severity. Here are our simplest favourites:

• Drink more water: oh, we know, doesn’t drinking more water mean more water intake and swelling? Actually, it’s the opposite. Drinking water helps your body balance fluids and avoid retaining excess fluids, reducing the likelihood of swelling.
  
• Move your body often: where possible, when you’re on long flights or car rides, take short breaks to walk around and stretch. It seems almost too simple, but it really does make a big difference (trust us, many of our podiatrists are prone to swelling). Try on-the-spot calf raises if you can only stand in one spot, or rolling your ankles in a circular pattern if you’re confined to being seated - they’ll both still help to boost circulation and keep blood moving, and hence swelling minimised.
  
• Compression socks (stockings) - get them, wear them, love them. Seriously - compression socks are excellent for helping prevent fluid from pooling in your lower legs, supporting blood vessels and reducing swelling. Get the medical grade compression socks and have them fitted so you know you’ve got the right compression level (we can help). These are also amazing for pregnancy, after surgery, and everything in between.
  
• Try your best to stay in shaded or air-conditioned areas when possible, or use cooling pads or a fan to reduce heat around your feet and ankles. This isn’t always possible, but if you’re struggling with leg swelling and you have the choice of sitting outside in the heat for a meal or inside with the aircon, sacrifice the view and choose the air conditioning.
  
• Limit eating too much salt and chips: salty foods encourage your body to retain water. More water means more swelling. So try to avoid excessive salt, especially before and during flights.
  

Who is most at risk of swollen feet and ankles in the heat?

Wondering why your feet are swollen on holiday in warm weather but your friends' feet aren’t? There are certain factors that make some people more susceptible to foot swelling in the hot weather:

• Your age. Yeah - unfortunately, as we grow older, problems with our circulation (blood flow) tend to be more prevalent. This is especially true when we think of the feet, which are the furthest point away from our heart (that pumps the blood). 
  
• Health conditions: these include heart disease, kidney disease, liver disease, lymphatic issues, venous insufficiency, deep vein thrombosis, arthritis, infections, hormonal changes and obesity. 
  
• Medications: some medications, like blood pressure medications and anti-inflammatory drugs, tend to increase the chance of swelling.
  
• Foot or leg injuries: had a previous injury, or are you still dealing with one now? You may find that your feet tend to swell more than others, or the swelling is more pronounced in the hotter weather.
  
• Being pregnant. Pregnancy is notorious for foot and leg swelling related to everything from hormonal changes to the growing weight on your lower legs, veins and vessels. Add heat into the mix? And your risk grows even further.
  

What are the symptoms of swollen feet?

Swelling is generally easy to notice, but the severity can vary. Here are the common signs:

• Puffiness in the feet and ankles or lower legs
  
• A tight or heaving feeling in your feet
  
• Stiffness when trying to move the toes or ankles
  
• Pain after standing or sitting
  
• Indentation when you press on the skin, also known as pitting oedema (this one can be more serious)
  

Note: if you notice your swelling growing worse and worse, or it’s accompanied by other symptoms like shortness of breath, chest pain, pain or extreme redness, please be seen by a doctor ASAP.

What can you do to prepare for a trip?

A little preparation can go a long way in preventing and managing foot swelling on your holiday:

• Learn the simple exercises - toe stretches, ankle rolls, calf raises. So you feel comfortable with what to do if you find yourself sitting or waiting for prolonged periods
  
• Have a travel-friendly water bottle with you (and for every member of your family or travel group) that can easily clip to your bag
  
• Get into the habit of actively looking for places to stop, rest, and stretch if you’re driving, or identify comfortable resting spots on your travel itinerary.
  
• Buy your compression socks (and have them professionally fitted) before you go.
  

What should you pack to help if you're prone to your feet swelling in the heat?

If there are a few extra items (beyond compression socks) that may help if your feet tend to swell, it could be: 

• Shoes made of light, breathable materials that encourage airflow
  
• Socks that wick moisture away from your feet
  
• Cooling gel packs for when you need them to cool down and help reduce swelling
  
• Anti-inflammatory gel or pain relievers if your swelling tends to leave you feeling sore and uncomfortable 
  
• Open shoes that you can switch into if your foot swelling means you can’t fit your regular shoes comfortably
  

When should you seek medical advice if your feet swell on holiday?

Most cases of heat-related foot swelling resolve with rest, raising your feet (like on the couch, ideally above the level of your heart) with cold water and some air conditioning. We’d recommend taking the next step to seek medical help if:

• Your swelling is becoming severe, persistent, or worsening
  
• Your swelling is notably painful or is limiting your ability to walk
  
• You start having additional symptoms like difficulty breathing, chest pain, fever, or extreme redness.
  
• The swelling occurs unevenly in one leg and not the other, which could indicate a more serious condition, such as deep vein thrombosis (DVT).
  
• You're struggling to find ways to boost circulation, an experienced health professional is a valuable resource to find realistic ways to help improve poor circulation regardless of whether you're on holiday or at home.
  

FAQs

Why do my feet swell even when I drink plenty of water?

Drinking lots of water and staying hydrated is non-negotiable, but prolonged sitting or standing, hot weather, and poor circulation and issues can all still lead to swelling, even for the most well-hydrated person.

Try combining hydration with movement and compression socks to improve blood circulation to maximise your chances of swelling (or preventing it from developing).

Can certain foods help my swollen feet?

Eating potassium-rich foods like bananas, leafy greens, and avocados can help balance fluids and reduce swelling. As we mentioned earlier, avoid high-sodium foods, which can lead to fluid retention.

How long should I elevate my feet to help my swollen feet?

Aim for at least 15-20 minutes, ideally with your feet raised above heart level. Doing this a few times throughout the day can significantly reduce puffiness. It’s even better if you have your compression socks on and sit in a relaxed environment (but not essential).

Should I be worried if only one foot is swollen?

Swelling in just one foot can sometimes indicate a deeper issue, such as an injury, infection, or blood clot. If your feet swell in the heat or swelling is persistent or accompanied by pain or redness, please seek medical advice.

Does wearing thongs contribute to swollen ankles and feet?

Flip-flops provide minimal support, which can strain your feet and potentially worsen swelling. Supportive sandals or lightweight shoes with arch support are better options for preventing swollen feet.

Can using cooling foot spray help?

Yes, having cooling foot spray on hand can help give you some relief from the discomfort of swollen feet and ankles and stop foot swelling.

Why should I avoid overly hot baths?

You should avoid hot baths because they have the same effect as hot weather - they cause heat oedema as your body temperatures rise promoting fluid buildup and swelling. Keep your bath at your body temperature (or cooler). We love cold water baths.