More studies reveal potential health benefits of turmeric

Turmeric is an ingredient associated with a host of health benefits. Curcumin is a naturally-occurring chemical that provides the yellow colour in turmeric. Studies have shown that it has anti-inflammatory and anti-oxidative properties, that it can inhibit the growth of bacteria and fungi, and may be able to boost the immune system. Although among people taking turmeric as a medicine, there have been a small number of reports of autoimmune hepatitis,​ and drug-induced liver injury.

The first study of its kind now claims turmeric may be as good for treating indigestion as drugs to curb excess stomach acid.

Turmeric and its naturally active compound curcumin have long been used as a medicinal remedy, including for the treatment of indigestion, in South East Asia. But it’s not clear how well it compares with conventional drugs for this indication, largely because there have been no head to head studies.

Researchers in Thailand therefore randomly assigned 206 patients aged 18-70 with a recurrent upset stomach (functional dyspepsia) of unknown cause, recruited from hospitals in Thailand between 2019 and 2021, to one of three treatment groups for a period of 28 days.

These were: turmeric (two large 250 mg capsules of curcumin 4 times a day) and one small dummy capsule (69 patients); omeprazole (one small 20 mg capsule daily and two large dummy capsules 4 times a day (68 patients); and turmeric plus omeprazole (69 patients).

Patients in all three groups had similar clinical characteristics and indigestion scores, as assessed by the Severity of Dyspepsia Assessment score or SODA, at the start of the trial.

SODA scores indicated significant reductions in symptom severity by day 28 for pain (−4.83, –5.46 and −6.22) and other symptoms (−2.22, –2.32, and −2.31) for those in the combined, curcumin alone, and omeprazole alone groups, respectively. 

These improvements were even stronger after 56 days for pain (−7.19, –8.07 and −8.85, respectively) and other symptoms (−4.09, –4.12 and −3.71, respectively). 

SODA also captures satisfaction scores: these scarcely changed over time among the curcumin users, which might possibly be related to its taste and/or smell, suggest the researchers.

No serious side effects were reported, although liver function tests indicated some level of deterioration among curcumin users carrying excess weight, note the researchers.

They acknowledge the small size of the study, as well as several other limitations, including the short intervention period and lack of long-term monitoring data. Further larger, long term studies are needed, they say.

Nevertheless, they concluded: “This multicentre randomised controlled trial provides highly reliable evidence for the treatment of functional dyspepsia,”​ adding that “the new findings from our study may justify considering curcumin in clinical practice.”​

It follows a study from earlier this year when researchers succeeded for the first time in adding a highly purified form of curcumin to yogurt in a way that ensures it remains dissolved in the dairy product and preserves it, while tasting good.

Their discovery, published in Frontiers in Nutrition​, makes it possible to create a probiotic yogurt that contains no artificial preservatives but that still has a long shelf life and properties that may enhance good health. 

First author of the study, Dr Magdalena Buniowska-Olejnik, from the Institute of Food Technology and Nutrition at the University of Rzeszow, Poland, said: “It is well known that curcumin has anti-microbial, anti-inflammatory and immune-boosting effects. However, it is insoluble in water, which is one of the main reasons why our bodies are not able to absorb sufficient amounts for it to have a biological effect. We wanted to see if it was possible to create a dairy product containing curcumin in a bioavailable form that would also appeal to the consumer.”​

References:
‘Turmeric may be as good for treating indigestion as drug to curb excess stomach acid’
DOI: 10.1136/bmjebm-2022-112231
‘Purified curcumin instead of artificial additives can be used to preserve and enhance probiotic yogurt’
DOI: 10.3389/fnut.2023.1118752