With one in four Australian adults experiencing problems with incontinence, some people look to supplements for relief.

With ingredients such as pumpkin seed oil and soybean extract, a range of products promise relief from frequent bathroom trips.

But do they really work? Let’s sift through the claims and see what the science says about their efficacy.

What is incontinence?

Incontinence is the involuntary loss of bladder or bowel control, leading to the unintentional leakage of urine or faeces. It can range from occasional minor leaks to a complete inability to control urination and defecation.

This condition can significantly impact daily activities and quality of life, and affects women more often than it affects men.

Some people don’t experience bladder leakage but can sometimes feel an urgent need to go to the bathroom. This is known as overactive bladder syndrome, and occurs when the muscles around the bladder tighten on their own, which greatly reduces its capacity. The result is the person feels the need to go to the bathroom much more frequently.

There are many potential causes of incontinence and overactive bladders, including menopause, pregnancy and child birth, urinary tract infections, pelvic floor disorders, and an enlarged prostate. Conditions such as diabetes, neurological disorders and certain medications (such as diuretics, sleeping pills, antidepressants and blood-pressure drugs) can also contribute.

While pelvic muscle rehabilitation and behavioural techniques for bladder retraining can be helpful, some people are interested in pharmaceutical solutions.

What’s in these products?

A number of supplements are available in Australia that include ingredients used in traditional medicine for urinary incontinence and overactive bladders. The three most common ingredients are:

• Cucurbita pepo (pumpkin seed extract)
• glycine max (soybean extract)
• an extract from the bark of the Crateva magna or nurvala (Varuna) tree.

How are they supposed to work?

Pumpkin seeds are rich in plant sterols that are thought to reduce the testosterone-related enlargement of the prostate, as well as having broader anti-inflammatory effects. The seed extracts can also contain oleic acid, which may help increase bladder capacity by relaxing the muscles around the organ.

Soybean extracts are rich in isoflavones, especially daidzen and genistein. Like olieic acid, these are thought to act on the muscles around the bladder. Because isoflavones are similar in structure to the female hormone oestrogen, soy extracts may be most beneficial for postmenopausal women who have overactive bladders.

Crateva extract is rich in lupeol- and sterol-based chemicals which have strong anti-inflammatory effects. This has benefits not just for enlarged prostates but possibly also for reducing urinary tract infections.

Do they actually work?

It’s important to note that the government has only approved these types of supplements as “listed medicines”. This means the ingredients have only been assessed for safety. The companies behind the products have not had to provide evidence they actually work.

A 2014 clinical trial examined a combined pumpkin seed and soybean extract called cucurflavone on people with overactive bladders. The 120 participants received either a placebo or a daily 1,000mg dose of the herbal mixture over a period of 12 weeks.

By the end of study, those in the cucurflavone group went to the bathroom around three fewer times per day, compared with people in the control group, who only went to the bathroom on average one fewer time each day.

In a different trial, researchers examined a combination of Crateva bark extract with herbal extracts of horsetail and Japanese evergreen spicebush, called Urox.

For the 150 participants, the Urox formulation helped participants go to the bathroom less frequently when compared with placebo treatment.

After eight weeks of treatment, participants in the placebo group were going to the bathroom to urinate 11 times per day. Those in the Urox group were only going around to 7.5 times per day. And those who took Urox also needed to go to the bathroom one fewer time during the night.

Finally, another study also examined a Creteva, horsetail and Japanese spicebush combination, but this time in children. They were given either a 420mg dose of the supplement or a placebo, and then monitored for how many times they wet the bed.

After two months of taking the supplement, slightly more than 40% of the 24 kids in the supplement group wet the bed less often.

While these results may look promising, there are considerable limitations to the studies which means the data may not be reliable. For example, the trials didn’t include enough participants to have reliable data. To conclusively provide efficacy, final-stage clinical trials require data for between 300 and 3,000 patients.

From the studies, it is also not clear whether some participants were also taking other medicines as well as the supplement. This is important, as medications can interfere with how the supplements work, potentially making them less or more effective.

What if you want to take them?

If you have incontinence or an overactive bladder, you should always discuss this with your doctor, as it may due to a serious or treatable underlying condition.

Otherwise, your GP may give you strategies or exercises to improve your bladder control, prescribe medications or devices, or refer you to a specialist.

If you do decide to take a supplement, discuss this with your doctor and local pharmacist so they can check that any product you choose will not interfere with any other medications you may be taking.

Nial Wheate, Professor of Pharmaceutical Chemistry, Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.