‘It’s natural, so it's safe,’ they say. So we scrunch our noses, close our eyes, and down the bitter juice, or the sour paste, do a little convulsive dance, and hope for the best.

What’s the worse that can happen?

After all, natural remedies are better because they don’t have side effects, right? Well...not always.

A few days ago, Dr Varun Cheruparambath, MD, DM, Cardiologist at Medical Trust Hospital, Kochi, tweeted this:

In the Twitter thread, he talks about a man in his forties who was brought in with severe abdominal pain. The ultrasound scans revealed that the otherwise healthy man had calcium oxalate crystals in his renal tube.

The cause? Drinking the juice of Bilimbi fruit, a popular home in Kerala, known to help lower high cholesterol.

So how does a popular nuska to lower cholesterol lead to acute renal failure? FIT talks to Dr Cyriac Abby Philips, a liver specialist at the Ernakulam Medical Centre to get to the bottom of it.

According to Dr Abby Philips, the renal failure was caused due to the accumulation of oxalate crystals.

Oxalic acid is a natural substance found in many foods and is usually broken down and pushed out with urine.

“Irumban puli (Averrhoa bilimbi) or the Bilimbi fruit is commonly used for traditional treatment of high blood pressure and cholesterol,” says Dr Cyriac Abby Philips.

And it so happens to be very high in oxalate content.

“Drinking the concentrated juice of Irumban puli extracts have been demonstrated to cause severe kidney injury and kidney failure. This is because of the high levels of Oxalic acid present in it,” he explains.

Dr Abby Philips points to a case study of a 38-year-old man who drank a glass of Bilimbi juice for only 4 days daily before he was hospitalized for experiencing severe abdominal discomfort, nausea, and loss of appetite.

It must be clarified, however, that the fruit itself isn’t toxic. In fact, it comes from a wild tree commonly found in backyards in south India and is often used in cooking—especially pickles. It’s perfectly healthy when consumed as a fruit and in small doses.

In spite of the number of cases of ARF from drinking Irumban Puli juice reported in Kerala, you will still find the odd text forward touting it as the miracle cure for high cholesterol floating around various Whatsapp groups. And people continue to give it a go.

One reason for this could be that people are more inclined to trust something that's already a part of their diet. Another reason could be the lack of information and even oftentimes distrust in doctors and modern medicine.

Dr Abby Philips explains this as a difference between faith-driven and evidence-driven behaviors.

Furthermore, it's especially important to be well informed of what you consume, ensure you have proper guidance, and avoid ingesting concentrated or excess amounts of any ‘superfood.’

It is important to be careful when consuming foods that contain naturally occurring oxalic acid, especially if you're prone to kidney stones.

Here are some ways to consume them safely, while ensuring you get all the nutrients you need.

• Too much of anything can be bad, so make sure you have a balanced diet and consume oxalate-rich foods in measured quantities.
• Drink plenty of water to help your body flush out the oxalates, preventing them from forming crystals.
• Limit the consumption of other oxalate-rich foods, as well as sodium and sugar, both of which may contribute to kidney stones at high levels.
• Cooking spinach and other vegetables rich in oxalic acid can drastically reduce its oxalate content.