By Dr Sean Carey
Around 10,000 Indian, Bangladeshi, Nepalese and Pakistani restaurants and takeaways in the UK routinely serve up curry to a significant proportion of the country’s 62 million population. Curry is probably the nation’s most popular food. According to one recent estimate the sector is worth around £3.6 billion annually and employs some 80,000 people.
No surprises, then, that British newspaper editors are interested in publishing “curry” stories. In the last week alone, two reports about the likely role that curcumin, the bioactive substance which gives turmeric its yellow colouring, plays in human health have made the headlines.
The first story came from a study carried out at the Shobhaben Pratapbhai Patel School of Pharmacy and Technology Management in Mumbai. Researchers combined curcumin with piperine, an extract of black pepper, and the flavonoid quercetin, which is found in a wide variety of fruit and vegetables as well as black and green tea. The combination of the three substances called CPQ had a dramatic effect on blood glucose, body weight, cholesterol and triglycerides in “low-dose streptozotocin-induced diabetic rats.”
Co-author of the study, pharmacist Dr Ginpreet Kaur, who has a long-standing interest in metabolic syndrome — one of the most significant health problems among populations in advanced and developing economies — stated that CPQ “significantly decreases glucose transport, causing a decrease in its uptake. It is probably due to the presence of flavonoids in the combination which get attached to glucose transporters.” In the published paper, the authors soberly conclude that more work is required on CPQ “with the aim to elucidate the molecular and cellular mechanism involved with the usage of these nutraceuticals for the prevention of metabolic syndrome.”
The popular press in the UK, however, felt under no obligation to go along with the conventionally restrained language of the scientists in India. Under the headline “Fight the menace of obesity and diabetes… with turmeric” the Daily Mail suggested “if you wish to get rid of those extra kilos or are desperate to control your diabetes and cholesterol, then head straight to your kitchen spice cabinet.” It was only towards the end of the article on the “miracle in the kitchen” that a note of caution was sounded: “Medicinal properties of curcumin cannot be fully utilised due to its limited bioavailability in the body. To be effective as medicine, one would have to consume several spoonfuls of turmeric in one dose.”
Turmeric, a member of the ginger family, is cultivated widely throughout the tropics. It grows to around 90 centimetres (3 feet) in height. Most of the world’s supply of the herb originates in India, where in addition to its culinary and medicinal uses, it is also employed in Hindu wedding ceremonies and other religious rituals.
Both turmeric and curcumin are classified by the U.S. Food and Drug Administration (FDA) as ‘generally recognized as safe’ (GRAS). They are widely available as over-the-counter supplements in pharmacies and health food shops worldwide. For those wishing to try it, the good news is that very few adverse effects have been reported for either turmeric or curcumin in clinical trials. Attempts to restrict the use of turmeric and curcumin through the issue of patents by Western biotechnology companies – “bio piracy” in other words – led in 2011 to the setting up a Traditional Knowledge Digital Library (TKDL) by the Indian Government in order to “prevent misappropriation of traditional knowledge belonging to India at International Patent Offices.”
The second news story concerned the potential role of curcumin alongside chemotherapy for treating bowel cancer. Around 40,000 people in the U.K. are diagnosed with the disease each year. Thirteen years ago, researchers in the Oncology Department of the University of Leicester noted that only two of 500 patients diagnosed with colon cancer were of South Asian heritage, even though 20 per cent of the city’s population came from this group. Why the discrepancy? The scientists hypothesized that turmeric may be playing a causal role given its anti-inflammatory properties and popularity in traditional Indian (Ayurveda) and traditional Chinese medicine (TCM) for treating a wide variety of ailments, including arthritis, allergies, bronchitis, liver disorders, intestinal worms, and colic.
A team of researchers headed by Professor Will Steward at the University of Leicester’s Experimental Cancer Medicine Centre (ECMC) has received a grant of £1.1 million from Cancer Research UK and the National Institute for Health Research to build on what they and other researchers around the world have discovered in the meantime.
The first project the team will carry out at Leicester Royal Infirmary and Leicester General Hospital will determine whether curcumin can be used safely alongside conventional chemotherapy in the treatment of advanced bowel cancer. Previous studies have demonstrated that curcumin can enhance the ability of chemotherapy to kill bowel cancer cells in the laboratory. Forty patients are being recruited for the two-year trial, which will compare the effects of giving curcumin pills to three quarters of the patients a week before beginning conventional chemotherapy treatment.
Professor Steward commented: “Once bowel cancer has spread, it is very difficult to treat. The prospect that curcumin might increase the sensitivity of cancer cells to chemotherapy is exciting because it could mean giving lower doses, so patients have fewer side effects and can keep having the treatment longer. This research is at a very early stage, but investigating the potential of plant chemicals to treat cancer is an intriguing area that we hope could provide clues to developing new drugs in the future.”
The British media have widely reported on the Leicester research. Although the tabloid language was evidently designed to grab attention of readers –for example, the Daily Express began a piece with the line “powerful ‘curry pills’ could be the key to beating bowel cancer” – it was clear that at least on this occasion journalists were careful not to over hype the story, probably out of fear of creating unrealistic expectations about treating the disease among desperately ill patients.
One thing is certain. At a time of severe spending cuts imposed as part of the UK Government’s austerity drive, any news stories about how the consumption of specific foods may lead to positive outcomes, will be welcomed by the Department of Health. Such stories may educate “hard-to-reach” groups and bypass the need for expensive nationwide advertising campaigns.
A version of this article has also appeared at anthopologyworks.com
Dr Sean Carey is research fellow in the School of Social Sciences, University of Roehampton
* Published in print edition on 11 May 2012