On the 16th July I wrote about artichoke leaf extract (ALE) supplements for cholesterol lowering.  Evidence is also mounting for the usefulness of this plant supplement in the reduction of IBS symptoms (1,2).  In one study (2) 208 adults with IBS were given ALE for a two month period.  The individuals had a significant improvement whilst taking the supplement with a normalising of bowel pattern away from alternating constipation/diarrhoea toward normal.  The IBS sufferers also had a significant improvement in their total health-related quality of life scores.  The trials were small and provide preliminary evidence but it certainly seems that artichoke leaf extract is useful for an array of digestive complaints.  If you decide to try ALE supplements for the management of your IBS symptoms please follow the manufacturers dosage advice, taken in excess it may cause digestive upset.

When discussing IBS it is difficult not to mention the issue of food sensitivities or intolerances.  Some studies indicate that a large proportion of people afflicted with IBS have food sensitivities, very few have true food allergies, and that gas production and other IBS symptoms diminish when the sensitivities are discovered and the offending food(s) eliminated (3,4,5,6).  Assessing sensitivities can be quite subjective and therefore difficult to assess properly in a clinical-trial setting. 

Research suggests that some people with IBS may malabsorb the sugars lactose (found in milk), fructose (found in high concentrations in fruit juice and dried fruit) and sorbitol (found in diabetic and sugar-free products) (7).   Research shows that in a large majority of IBS patients with lactose malabsorption, a lactose-restricted diet can improve symptoms markedly both in the short term and the long term (8).  Fructose- and sorbitol-reduced diets in subjects with fructose malabsorption reduce gastrointestinal symptoms such as bloating, cramps, osmotic diarrhoea and other IBS symptoms (9).  Hence, individuals with IBS attempting to uncover food sensitivities should consider the possibility that milk, fruit juice, dried fruit and products containing sorbitol might cause worsening of their symptoms.

A note of caution – please do not attempt elimination diets without supervision from your GP or a fully qualified professional.  Many ‘food sensitivity tests’ are advertised at very high cost and, in my opinion, can often be unhelpful.  Working with a professional and keeping food diaries and symptom scores may uncover specific triggers for your personal symptoms.  Stress, emotions and psychology may also be playing a major role in your IBS symptoms so assessing how you feel could also prove helpful.  Foods may be triggering symptoms in conjunction with stressful/emotional periods but less-so at other times.

Finally I would like to briefly mention aloe vera juice.  Many individuals with digestive complaints report that their symptoms diminish greatly with the regular ingestion of an aloe vera juice drink or supplemental aloe capsules.  Most of the evidence so far is anecdotal (but that does not lessen personal experiences).  A few animal studies have started to provide weight to the evidence but very few human studies have occurred to date.  A test tube study(10) using human colon cells has shown that aloe vera did appear to work as a potent anti-inflammatory.  You may find it useful to try the juice yourself to see if it is helpful in reducing your personal symptoms.  Remember to follow the dosage guidance and try and keep note of your symptoms for about a week.  If the juice works for you then it is worth continuing with. 

That ends my posts on IBS, I do hope that the information presented over the last few days has been of help?!

(1)Walker AF et al.  2001.  Artichoke leaf extract reduces symptoms of irritable bowel syndrome in post-marketing surveillance study.  Phytotherapy Research.  15:58-61
(2)Bundy R et al.  Artichoke leaf extract reduces symptoms of irritable bowel syndrome and improves quality of life in otherwise healthy volunteers suffering from concomitant dyspepsia: a subset analysis.  J Altern Complement Med.  10:667-669
(3) King TS et al.  1998.  Abnormal colonic fermentation in irritable bowel syndrome.  Lancet.  352:1187-1189
(4) Jones AV et al.  1982.  Food intolerance: a major factor in the pathogenesis of irritable bowel syndrome.  Lancet.  ii:1115-1117
(5) Smith MA et al.  1985.  Food intolerance, atopy, and irritable bowel syndrome.  Lancet.  ii:1064
(6) Parker TJ et al.  1995.  Management of patients with food intolerance in irritable bowel syndrome: the development and use of an exclusion diet.  J Human Nutr Diet.  8:159-166
(7) Fernandez-Banares F et al.  1993.  Sugar malabsorption in functional bowel disease: clinical implications.  Am J Gastroenterol.  88:2044-2050.
(8) Bohmer CJ, Tuynman HA.  2001.  The effect of a lactose-restricted diet in patients with a positive lactose tolerance test, earlier diagnosed as irritable bowel syndrome: a 5-year follow-up study.  Eur J Gastroenterol Hepatol.  13(8):941-944
(9)Ledochowski M et al.  2000.  Fructose- and sorbitol-reduced diet improves mood and gastrointestinal disturbances in fructose malabsorbers.  Scand J Gastroenterol.  35(10):1048-52
(10)Langmead L et al.  2004.  Anti-inflammatory effects of aloe vera gel in human colorectal mucosa in vitro.  Aliment Pharmacol Ther.  19:521-527

Written by Ani Kowal

Last weekend I had the most delicious artichoke and broad bean salad and it spurred me into thinking about the health benefits of artichoke.  More and more people are taking a supplement of artichoke leaf extract for a variety of reasons.  Artichoke leaf extract is made from the thistle-like leaves at the base of the stem of the Globe Artichoke (botanical name Cynara scolymus) and not from the (very tasty!) artichoke heart that we use in cooking.

Quite a lot of recent research into artichoke leaf extract in the UK has come from the University of Reading and has mostly concentrated on the positive effects of the herb on the digestive system.  Studies have indicated that it may alleviate irritable bowel syndrome(1, 2) and indigestion(3,4). 

However, the latest research, published online last month, has found that artichoke leaf extract is also very effective at reducing cholesterol levels(5).  Many people are now taking statins in order to try and reduce their high cholesterol levels.  Taking steps through diet, exercise and perhaps supplements, before cholesterol levels reach a high could help to reduce the need for drugs (it is my personal opinion that prevention is always better than cure).  This piece of research is important because the study involved healthy people who had only moderately raised blood plasma cholesterol levels (not yet needing drugs) and it was found that the artichoke leaf extract was helpful in reducing their blood cholesterol concentrations.

The trial involved 75 individuals with total plasma cholesterol in the range 6.0–8.0 mmol/l and lasted 12 weeks.  The participants took 1280 mg of a standardised artichoke leaf extract (4 capsules), or a placebo each day.  Plasma total cholesterol decreased significantly in the treatment group (compared to the placebo) by an average of 4.2%.  This may seem like a modest change but it is favourable and certainly significant.

Dr Rafe Bundy, the lead study scientist, is quoted as saying “Reducing cholesterol levels can reduce the risk of developing cardiovascular disease. Our research investigated whether ALE [artichoke leaf extract] could be beneficial to otherwise healthy people who had raised levels of cholesterol but were not yet at a stage where they needed standard medical intervention. ALE may provide another option which people could try over and above a healthy diet in order to help lower plasma cholesterol.”

Artichoke leaf extract may be having an effect via antioxidant action, though the exact mechanism is not clear.  The extract contains a variety of polyphenols/flavonoids (bio-active plant chemicals) such as Caffeic Acid, Chlorogenic Acid and a group of compounds collectively called Caffeoylquiinic Acids (e.g. Cynarin), these are probably the active substances responsible for the beneficial health effects.

Artichoke leaf extract is widely available as a supplement and often supplements are standardised to contain around 15% Chlorogenic Acid and 2-5% Cynarin.  Typically around 600mg-900mg per day is recommended (check the recommended dose on the label) for improved digestion and cholesterol lowering.

(1) Walker AF et al.  2001.  Artichoke leaf extract reduces symptoms of irritable bowel syndrome in a post-marketing surveillance study.  Phytotherapy Research.  15(1):58-61.
(2)Bundy R et al.  2004.  Artichoke leaf extract reduces symptoms of irritable bowel syndrome and improves quality of life in otherwise healthy volunteers suffering from concomitant dyspepsia: a subset analysis.  J Altern Complement Med.  10(4):667-669.
(3)Marakis G et al.  2002.  Artichoke leaf extract reduces mild dyspepsia in an open study.  Phytomedicine.  9(8):694-699.
(4) Holtmann G et al.  2003.  Efficacy of artichoke leaf extract in the treatment of patients with functional dyspepsia: a six-week placebo-controlled, double-
blind, multicentre trial.  Aliment Pharmacol Ther.  18(11-12):1099-1105.
(5)Bundy R et al.  2008.  Artichoke leaf extract (Cynara scolymus) reduces plasma cholesterol in otherwise healthy hypercholesterolemic adults: a randomised double-blind placebo controlled trial. Phytomedicine [Epub ahead of print DOI: 10.1016/j.phymed.2008.03.001 doi:10.1016/j.phymed.2008.03.001]    

Written by Ani Kowal