If your shoes feel tighter every summer, or your socks are leaving deep marks by the end of the day, you’re not imagining it. Swollen ankles and legs in hot weather are extremely common, especially for people over 60. Most of the time it’s simply how your body responds to heat — but it can occasionally be a sign of something that needs medical attention. Here are the three main reasons this happens, what actually helps, and the warning signs worth knowing. (Based on the insights of Dr. Suneel Dhand)
Key Takeaways
- Heat causes ankle and leg swelling through expanding blood vessels and reduced calf muscle pumping, especially with prolonged sitting.
- Moving at least once an hour and elevating your legs above heart level for short periods can meaningfully reduce swelling.
- Certain medical conditions and medications, including some blood pressure drugs, can also contribute to ankle swelling.
- Heat-related swelling is typically symmetrical (both legs), painless, and improves overnight.
- Swelling that’s painful, red, warm, one-sided, or paired with chest pain or shortness of breath needs prompt medical attention.
Reason #1: Your Blood Vessels Expand
Just like most things expand as they warm up, the veins in your legs widen in hot weather, which allows more fluid to leak into the surrounding tissue. Gravity makes this worse, since your feet and ankles are the lowest point of your body — which is why swelling tends to build throughout the day and is usually less noticeable first thing in the morning.
What helps: elevating your feet above heart level for short periods, even just 20 minutes at a time, can make a real difference when this is the underlying cause.
Reason #2: Your Calf Muscles Aren’t Pumping Enough
Your calf muscles work almost like a second heart — every step helps pump blood back up toward your heart. When you’re sitting for extended periods, whether it’s because it’s too hot to be active, you’re traveling, or just relaxing indoors, blood and fluid can start to pool around your ankles.
What helps: moving at least once an hour, even for just a few minutes. Walking, standing, rotating your ankles, or marching in place all help keep that pumping action going — even for people who find walking difficult, seated leg movements can help.
Reason #3: Underlying Medical Conditions
Sometimes it isn’t just the heat. Conditions such as heart failure, kidney disease, liver disease, poor circulation, and peripheral vascular disease can all exacerbate ankle swelling. Certain medications can contribute too — blood pressure medications like amlodipine (brand name Norvasc) are a commonly cited example. It’s worth not automatically assuming every swollen ankle is simply due to summer heat.
A Note on Electrolytes
Sweating more in hot weather means losing sodium along with other electrolytes like potassium and magnesium, which doesn’t help the situation. For most people with normally functioning kidneys, maintaining adequate salt intake in hot weather is actually important rather than something to restrict aggressively. That said, this is genuinely different for people with certain health conditions — anyone with kidney disease, heart failure, or a condition affecting sodium levels should follow their doctor’s specific guidance rather than general advice.
When Swelling Is Just the Heat vs. When to Worry
Heat-related swelling typically affects both legs and ankles equally, tends to improve overnight, isn’t particularly painful, and doesn’t usually come with redness.
Seek medical attention promptly if any of the following apply: one leg is significantly more swollen than the other, the area is painful, red, or warm to the touch, or the swelling is accompanied by chest pain, shortness of breath, or heart palpitations. These can be signs of something like a blood clot, particularly if you’ve been relatively stationary, and warrant urgent evaluation — often with an ultrasound or CT scan at an urgent care facility or emergency room.
Practical Tips for Reducing Heat-Related Swelling
- Avoid being too stationary — keep moving throughout the day
- Stay well hydrated, aiming for several glasses of water daily, up to 10–15 on very hot or high-sweat days
- Maintain electrolyte intake alongside your water intake
- Avoid standing in one place for prolonged periods
- Elevate your legs above heart level for brief periods when possible
- Wear loose-fitting clothing, and avoid socks or pants that are too tight
- Ask your doctor about compression stockings, which many people find helpful
Frequently Asked Questions
Is ankle swelling in summer always harmless?
Usually, but not always. Heat-related swelling typically affects both legs equally, isn’t painful, and improves overnight. Swelling that’s one-sided, painful, red, or warm to the touch is different and should be checked promptly, since it can signal something like a blood clot.
Why does swelling get worse throughout the day?
Gravity plays a role — since your feet and ankles are the lowest point of your body, fluid tends to accumulate there over the course of the day, which is why swelling is usually more noticeable in the evening than in the morning.
Should I cut back on salt if my ankles are swelling?
Not necessarily, for most people with normally functioning kidneys — sweating causes sodium loss too. However, anyone with kidney disease, heart failure, or a condition affecting sodium levels should follow their doctor’s specific guidance rather than general advice.
What’s the fastest way to reduce swelling if it’s just the heat?
Elevating your legs above heart level for around 20 minutes, along with moving regularly throughout the day to keep your calf muscles active, are the two most effective simple steps.
Quick Start Checklist
- ☐ Move at least once every hour, even indoors
- ☐ Elevate your legs above heart level for 20 minutes when possible
- ☐ Stay hydrated with water and electrolytes, especially on hot days
- ☐ Wear loose-fitting clothing and avoid tight socks or pants
- ☐ Ask your doctor about compression stockings
- ☐ Seek medical attention if swelling is one-sided, painful, red, warm, or paired with chest pain or shortness of breath
Source: Dr. Suneel Dhand
Disclaimer: This article is for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. If you experience swelling with pain, redness, warmth, or that affects one leg significantly more than the other, or swelling accompanied by chest pain, shortness of breath, or palpitations, seek medical attention promptly.