Fluid retention, oedema, means fluid collects in the tissue instead of being returned to the blood and lymph. The most common forms are swollen feet and ankles in the evening, a puffy face in the morning and tight rings in hot weather, usually caused by sitting, standing, heat, salty food, hormonal swings or a long flight. It passes with movement, legs up, less salt and light lymphatic massage. But swelling can also be a sign of disease in the heart, kidneys, liver, veins or lymphatic system, or a side effect of medication, and then it must be investigated. Here are the causes, the warning signs that mean you should seek care, and the self-care that works when the swelling is harmless.
Why does fluid collect?
Every day fluid leaks out of the small blood vessels into the tissue and is returned by veins and lymph vessels. The balance is disturbed when the pressure in the veins rises (standing or sitting for long, pregnancy, varicose veins), when the protein level of the blood falls (liver and kidney disease, malnutrition), when the vessel walls become leaky (heat, inflammation, allergy) or when the lymph cannot keep up (sluggish flow or damaged lymph vessels). Salt binds water, and hormones before menstruation and in menopause make the body hold more fluid. More on the role of the lymph in The lymphatic system – how it works.
Common causes
| Cause | Recognised by | What helps |
|---|---|---|
| Sitting, standing work, flights | Both feet and ankles swollen in the evening, gone in the morning | Movement breaks, calf raises, legs up, support stockings when travelling |
| Heat | Swollen hands and feet on hot days | Cooling, water, movement in water |
| Salt and alcohol | Puffy face and fingers the day after | Less salt, more water, potassium from vegetables |
| Hormones (menstruation, pregnancy, menopause) | Recurring swelling in the cycle, swollen feet late in pregnancy | Movement, legs up, light lymphatic massage; in pregnancy see the pregnancy guide |
| Varicose veins and venous insufficiency | Heavy, aching legs, visible veins, swelling that increases during the day | Compression stockings through healthcare, movement; do not cup over varicose veins |
| Medication | Swelling that started when you changed medication (e.g. some blood pressure drugs, cortisone, anti-inflammatories, hormones) | Talk to your doctor, do not change on your own |
| Heart, kidney or liver disease | Swelling in both legs that does not go away, breathlessness, rapid weight gain, swollen abdomen | Healthcare, investigation |
| Lymphoedema | Usually one side, including foot/hand, persists in the morning | Lymphoedema therapist, see Lymphoedema |
When should you seek care?
Same day or urgently: swelling in one leg that came on suddenly, especially with pain, warmth or redness (suspected blood clot or infection); swelling together with breathlessness, chest pain or difficulty lying flat; swelling of the face and hands during pregnancy, especially with headache or visual disturbances; swelling of the lips, tongue or throat (allergic reaction).
Within days to weeks via your GP: swelling that does not go away by morning, that increases week by week, that is on one side only, that began with a new medication, or that is accompanied by fatigue, rapid weight gain, less urine or yellowish skin.
Self-care when the swelling is harmless
- Move your calves. Ten calf raises every hour at the desk, a walk every day. The calf muscle pumps both blood and lymph upwards.
- Legs up. 15–20 minutes with your feet above heart level in the evening.
- Cut the salt and drink water. Less salt makes the body release fluid; drinking less does not help, rather the opposite.
- Compression when needed. Support stockings on long flights, for standing work and in late pregnancy.
- Light lymphatic massage. Stroke, or glide an oiled silicone cup with very light pressure, from the feet towards the backs of the knees and from the knees towards the groin, 5–10 minutes. The technique is in Lymphatic massage at home, the background in What is lymphatic massage? Curam Dynamic Cup for legs, Dynamic Mini Cup for ankles and arms.
- Cooling and movement in water on hot days; the water pressure works as mild compression.
Diuretic teas, "detox" and sweat belts do not remove oedema in any lasting way. Diuretic medicines should only be used on a doctor's prescription.
A swollen face in the morning
A puffy face and under-eye bags in the morning are almost always harmless fluid after a night lying down, made worse by salt, alcohol, allergies or crying. Five minutes of lymphatic massage from the centre of the face towards the ears and down towards the collarbones removes most of it. See Lymphatic massage for the face. Facial swelling that does not go away, or that comes with breathing difficulties, must be assessed by healthcare.
Sources
- 1177 Vårdguiden (Swedish): search "svullna ben", "ödem" and "blodpropp i benet" for symptoms and when to seek care.
- Curam's guides on lymph and swelling: Swollen legs and feet, Lymphoedema.
Frequently asked questions about fluid retention
Why do my feet swell in the evening?
Because fluid collects in the lowest parts of the body when you have sat or stood for long and the calf muscle has not pumped enough. If it is gone by morning it is almost always harmless.
How do I get rid of fluid in the body quickly?
Movement, legs up, less salt, water and light lymphatic massage take effect within hours. There are no harmless shortcuts; diuretics should only be used on a doctor's prescription.
Does lymphatic massage help fluid retention?
Yes, for ordinary, passing swelling. Light pressure in the direction of lymph flow moves fluid towards the lymph nodes, and the effect is often noticeable the same day. Swelling caused by disease requires treatment of the cause.
Is swelling in one leg dangerous?
One-sided swelling that came on suddenly can be a blood clot and must be assessed the same day, especially with pain, warmth or redness. Slowly increasing one-sided swelling can be lymphoedema and should be investigated.
Can cupping make swelling worse?
Dynamic cupping with light pressure towards the heart helps with harmless swelling. Strong suction, static cups on swollen areas, cupping over varicose veins or on a limb with lymphoedema can make it worse. When not to cup: When to avoid cupping.
Written by Curam. Last updated 17 October 2026. This is general information and does not replace medical care. Lymphoedema and unexplained swelling must always be assessed and treated through healthcare (GP, lymphoedema therapist). Curam sells massage cups for self-care, not medical treatment.
