Swollen feet and ankles usually respond well to a few simple strategies you can start today: elevating your legs, moving more, cutting back on salt, and wearing compression socks. The swelling happens when fluid shifts out of your blood vessels and pools in the tissue around your ankles and feet, pulled there by gravity throughout the day. Most of the time it’s not dangerous, but certain patterns of swelling deserve medical attention.
Why Fluid Pools in Your Feet
Your body is constantly moving fluid between your bloodstream and surrounding tissues. When pressure inside small blood vessels rises, or when those vessels become leakier than normal, more fluid seeps out than your body can drain back. Gravity does the rest, pulling that extra fluid downward into your feet and ankles, especially if you’ve been sitting or standing for hours.
Once fluid starts accumulating, your kidneys respond by holding onto more sodium and water to replace what left the bloodstream. This creates a cycle: the more fluid leaks out, the more your body retains to compensate, and the puffier your lower legs become. Anything that disrupts this balance (a high-salt meal, a long flight, hormonal shifts during menstruation or pregnancy, or a medication like a blood pressure drug or anti-inflammatory) can trigger noticeable swelling.
Elevate Your Legs Above Your Heart
Elevation is the fastest way to move trapped fluid back toward your core. The key detail most people miss is height: your feet need to be above the level of your heart, not just propped on an ottoman. Lie on a couch or bed and stack pillows under your calves and ankles until your feet are clearly higher than your chest. Aim for about 15 minutes per session, three to four times a day. Even two sessions can make a visible difference by evening.
If you work at a desk, a footrest that angles your legs upward helps slow the rate of fluid accumulation during the day, though it won’t replace full elevation sessions at home.
Simple Exercises That Push Fluid Out
Your calf muscles act as a pump for blood returning to your heart. Every time they contract, they squeeze the veins in your lower legs and push fluid upward. When you sit still for long stretches, that pump shuts off and fluid stagnates. Even small, deliberate movements can restart it.
Three exercises work well and can be done sitting in a chair or lying in bed:
- Heel and toe raises: With feet flat on the floor, pull your toes up toward your shins while keeping your heels down. Then reverse it: point your toes toward the floor and lift your heels. Repeat 10 times.
- Ankle circles: Rotate one ankle clockwise 10 times, then counterclockwise 10 times. Switch to the other ankle.
- Walking: Even a five-minute walk every hour engages your calf pump far more than any seated exercise.
Doing these exercises twice a day, and adding short walks throughout the day, is one of the most effective habits you can build for chronic swelling.
How Compression Socks Help
Compression stockings apply graduated pressure to your lower legs, tightest at the ankle and looser toward the knee. This steady squeeze keeps fluid from settling into the tissue in the first place and supports those calf-muscle pumps as you move.
Compression levels are measured in millimeters of mercury (mmHg), and the right level depends on how much swelling you’re dealing with:
- 15 to 20 mmHg (mild): Good for occasional puffiness, long flights, or standing all day at work. Available without a prescription at most pharmacies.
- 20 to 30 mmHg (moderate): The most commonly prescribed level for recurring lower-leg swelling. This is the range most people with persistent ankle edema end up using daily.
- 30 to 40 mmHg (firm): Used for more significant swelling or chronic venous problems. Usually fitted by a specialist.
Put compression socks on first thing in the morning, before you stand up and fluid has a chance to pool. They’re far less effective if you wait until your ankles are already swollen.
Reduce Your Sodium Intake
Sodium tells your kidneys to hold onto water. The more salt you eat, the more fluid your body retains, and gravity sends that extra fluid straight to your ankles. The American Heart Association recommends no more than 2,300 milligrams of sodium per day, with an ideal target of 1,500 milligrams for most adults. To put that in perspective, a single fast-food sandwich can contain over 1,000 milligrams.
The biggest sources of hidden sodium aren’t the salt shaker on your table. They’re processed and packaged foods: canned soups, deli meats, frozen meals, bread, condiments, and restaurant dishes. Reading nutrition labels and cooking more meals at home are the two changes that make the largest dent. Many people notice a meaningful reduction in foot swelling within a few days of cutting back.
Potassium, Magnesium, and Fluid Balance
Electrolytes like potassium and magnesium play a direct role in regulating how much fluid your body holds onto. Potassium works as a counterbalance to sodium: it helps your kidneys release excess sodium and the water that follows it. Magnesium supports nerve and muscle function, including the muscles in your blood vessel walls that help regulate fluid movement.
You don’t necessarily need supplements. Potassium-rich foods include bananas, potatoes, spinach, avocados, and beans. Good sources of magnesium include nuts, seeds, dark leafy greens, and whole grains. A diet that leans on whole foods over processed ones naturally shifts your electrolyte balance in a direction that reduces fluid retention.
Other Strategies Worth Trying
Soaking your feet in cool water can temporarily constrict blood vessels and reduce the rate of fluid leaking into tissues. Some people find Epsom salt baths helpful, likely because the magnesium in the salt absorbs through the skin in small amounts, though the cooling effect probably matters more than the mineral content.
If you’re overweight, the extra body mass puts more pressure on the veins returning blood from your legs. Even modest weight loss can meaningfully reduce chronic ankle swelling by taking pressure off those vessels. Staying well hydrated also helps, counterintuitive as that sounds. When you’re dehydrated, your kidneys respond by retaining more sodium and water, which worsens swelling rather than improving it.
When Swelling Signals Something Serious
Swelling in both ankles after a long day on your feet is common and usually harmless. But certain patterns are red flags. Swelling in only one leg, especially if it comes on suddenly and is accompanied by pain, warmth, or redness, can indicate a blood clot in a deep vein. This requires prompt medical evaluation.
The most common cause of chronic swelling in both ankles is weakened valves in the leg veins, a condition called venous insufficiency. It’s not an emergency, but it tends to worsen over time without management. New swelling that doesn’t have an obvious explanation (like a salty meal or a long flight) is also worth discussing with a doctor, since fluid retention can sometimes point to kidney, liver, heart, or thyroid problems.
Call 911 if swollen legs are accompanied by chest pain, difficulty breathing, shortness of breath when lying down, dizziness or fainting, or coughing up blood. These combinations can signal a blood clot that has traveled to the lungs or a serious heart condition.