Brief Answer:
Edema

Detailed Answer:

Swollen ankles and feet (referred to medically as oedema) can be caused by a number of reasons from too much salt in your diet, prolonged sitting or standing (such as a lengthy car journey or flights). This type of oedema is typically mild and temporary; however it can be uncomfortable and painful at times.also during the summer months, especially during heat waves or when someone is exposed to more heat than usual, such as when holidaying aboard, heat oedema is common and can cause ankles, feet and even legs to swell more than usual. this typically occurs due to vasodialation of veins when you are too hot..
you can decrease the oedema and swelling by the following measures

first you should elevate your feet as much as possible. it is recommended to raise your legs/feet higher than your heart, 3-4 times a day for 30 minutes each – depending on the severity of the swelling. When you go to bed you can also put a pillow under your ankles to help drain the excess fluid.

second you should avoid heat as much as possible
and avoid sitting in direct sunlight. Find shaded areas to sit in or seek out air conditioned rooms where possible .Avoid excessively hot baths, hot showers and saunas as these can worsen swelling.

also you should stay active by gentle exercise such as walking

it is also important that you drink plenty of water and limit salt intake in your diet.
Try to aim for at least 8-10 glasses of plain water a day and try to use a low-sodium alternative or reduced salt varieties of foods which are usually high in salt, such as soups, sauces, crisps and smoked meats. Try to avoid eating highly processed foods as these often have a high salt content. also add more fresh fruit and vegetables that have diuretic effect into your diet such as beetroot, leafy greens such as lettuce and spinach, pumpkin, green beans, asparagus, onion, lemons and pineapple.

if these measures did not help then you should consider using Support tights or compression socks can help prevent swelling and use Magnesium which is an important mineral for blood circulation so it’s no XXXXXXX that a deficiency in the amount of magnesium in the body can often lead to swelling. A dose of 200mg taken twice a day can make a difference.. I hope I answered your question.

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