Diuretics are substances that increase the amount of urine you produce and help your body get rid of excess water.
This excess water is called water retention. It can leave you feeling “puffy” and cause swollen legs, ankles, hands and feet.
Various factors can cause water retention, including some serious underlying health conditions like kidney disease and heart failure.
However, lots of people experience mild water retention due to things like hormonal changes, their menstrual cycle or simply being inactive for long periods of time, such as during a long flight.
If you have water retention due to a health condition or experience sudden and severe water retention, you should seek medical advice from your doctor immediately.
However, for cases of mild water retention that aren’t caused by an underlying health condition, there may be some foods and supplements that can help.
Here are the top 8 natural diuretics and a look at the evidence behind each one.
Coffee is a very popular drink that has been linked to some impressive health benefits.
High doses of caffeine between 250–300 mg (the equivalent of about two to three cups of coffee) are known to have a diuretic effect (2).
This means that drinking a few cups of coffee could cause an increase in urine production.
However, a standard serving of coffee, or about one cup, is unlikely to contain enough caffeine to have this effect.
Summary: Drinking one to two cups of coffee may act as a diuretic and help you lose some water weight in the short term. However, you can build a tolerance to coffee’s diuretic properties and not experience any effects.
It’s been suggested as a potential diuretic due to the high potassium content of the dandelion plant (6).
Eating potassium-rich foods signals your kidneys to pass out more sodium and water (7).
This may be a good thing, as most modern diets are very high in sodium and low in potassium, which can cause fluid retention (8).
In theory, the high potassium content of dandelion means that this supplement could help you shed excess water caused by a high sodium intake.
However, the actual potassium content of dandelion may vary, thus so may its effects (6).
Animal studies investigating the diuretic effects of dandelion have found mixed results (4).
There are only a few studies on its effects in people. However, one small human study found that taking a dandelion supplement increased the amount of urine produced in the five hours after taking the supplement (9).
Overall, little is known about the diuretic effects of dandelion in people, so more studies are needed (4).
Summary: Dandelion extract is a popular herbal supplement thought to be a diuretic due to its high potassium content. One small human study found that it had diuretic effects, but more research is needed.
Horsetail is an herbal remedy made from the field horsetail plant, or Equisetum arvense.
It has been used as a diuretic for years and is available commercially both as a tea and in capsule form.
Despite its conventional use, very few studies have examined it (10).
One small study in 36 men found that horsetail was as effective as the diuretic medication hydrochlorothiazide (11).
Although horsetail is generally considered safe, it’s not recommended for long-term use. It also shouldn’t be taken by people who have a pre-existing health condition like kidney disease or diabetes (12).
More studies are needed to confirm its diuretic effects (10).
Keep in mind that herbal remedies can also contain varying amounts of their active ingredient, so their effects can vary.
Summary: Horsetail is an herbal remedy that has been conventionally used as a diuretic for mild water retention. One small study found it to be as effective as the diuretic medication hydrochlorothiazide.
Parsley has long been used as a diuretic in folk medicine. Traditionally, it was brewed as a tea and taken several times a day to reduce water retention (10).
Studies in rats have shown that it can increase urine flow and exert a mild diuretic effect (13).
However, no human studies have examined how effective parsley is as a diuretic.
As a result, it’s currently unknown if it has the same effect in people, and if so, what doses are most effective.
Summary: Parsley has traditionally been used as a diuretic and may have a mild diuretic effect. However, there are no human studies, so its effects remain unclear.
Hibiscus is a family of plants known for producing beautiful and brightly colored flowers.
One part of this plant, known as the calyces, has commonly been used to make a medicinal tea called “roselle” or “sour tea.”
Although there is limited evidence, sour tea is said to have a number of health benefits, including lowering blood pressure in people with hypertension (14).
It’s also promoted as a diuretic and an effective remedy for mild fluid retention.
One study in Thailand gave 18 people 3 grams of hibiscus in sour tea daily for 15 days. However, they found that this had no effect on urine output (14).
Summary: Hibiscus may have a mild diuretic effect. However, it has not yet been proven effective in a human study.
Caraway is a feathery plant also known as meridian fennel or Persian cumin.
It’s often used as a spice in cooking, especially in foods like bread, cakes and desserts.
Ancient therapies that use plants as medicine, such as Ayurveda in India, use caraway for a variety of medicinal purposes, including digestive disorders, headaches and morning sickness (18).
In Moroccan medicine, caraway is also used as a diuretic.
One study in rats found that giving caraway extract in liquid form significantly increased urine output over 24 hours (19).
However, this is the only study on the diuretic effects of caraway, so much more research is needed before proving its diuretic effects, especially in humans.
Summary: Caraway has been shown to increase the urine output of rats over 24 hours. However, there are no human studies, so more research is needed.
Both black and green tea contain caffeine and can act as diuretics.
In rats, black tea has been shown to have a mild diuretic effect. This has been attributed to its caffeine content (20).
However, as is the case with coffee, you can develop a tolerance to the caffeine in tea.
This means that the diuretic effect is only likely to occur in people who do not regularly drink tea (3).
Summary: The caffeine content of green and black tea has a mild diuretic effect. However, this effect wears off as people build a tolerance to it. It’s therefore unlikely to act as a diuretic in those who regularly drink these teas.
Nigella sativa, also known as “black cumin,” is a spice promoted for its medicinal properties, including its diuretic effect (21).
This effect may partly be explained by its diuretic effects (25).
However, no human studies have been carried out. Therefore, it’s unclear whether Nigella sativa has a diuretic effect in people or animals who don’t have high blood pressure.
Additionally, the doses used in the studies were much higher than the amounts you would get by adding this herb to your food (25).
Summary: Animal studies have shown that Nigella sativa may be an effective diuretic for animals with high blood pressure. Its effects in people and animals with normal blood pressure are unknown.
Other strategies may also help you reduce fluid retention.
- Exercise: Physical activity can help get rid of extra fluid by increasing blood flow to your tissues and making you sweat (26, 27).
- Increase your magnesium intake: Magnesium is an electrolyte that helps regulate fluid balance. Magnesium supplements have been shown to help reduce fluid retention in women with premenstrual syndrome (28).
- Eat potassium-rich foods: Eating potassium-rich foods can increase urine production and decrease sodium levels, reducing fluid retention (29).
- Stay hydrated: Some people think that dehydration can increase your risk of water retention (32).
- Consume less salt: A high-salt diet can promote fluid retention (30, 31).
Summary: Exercising, consuming less salt and eating more potassium-rich foods may help reduce fluid retention. Women with premenstrual syndrome may also benefit from taking a magnesium supplement.
Including some of these foods and drinks in your diet may help with mild fluid retention.
However, many of them lack solid evidence for their effects, so they may be a bit hit-or-miss.
That said, combining some of them with other healthy changes, such as eating healthy, exercising and drinking enough water, may help get rid of that puffy feeling.