Luteolin Supplements for Autism May Have Unwanted Consequences
Flavonoids are a category of nutritional substances found in over 6,000 different forms. Primarily, the provide plants with their many brilliant colors but also have a great deal of nutritional value for humans. Most function in the body as antioxidants, protecting against the damage done by oxygen-containing molecules. They are also anti-inflammatory and may contain antibiotic activity.
Although there is not yet a “daily recommended value” for flavonoids, it is important to get a variety of these nutrients in daily to protect against deficiency (symptoms include excessive bruising, nose bleeds, swelling after injury, and frequent infections.) They may also be the key for protecting the body against certain diseases.
One particular flavonoid called luteolin has been studied as a potential treatment for autism due to its antioxidant, anti-inflammatory, and neuroprotective properties. A 2012 study published in the International Journal of Immunopathology Pharmacology found that children treated with a luteolin-based formulation had 75% improved GI and allergy symptoms, 50% improved eye contact and attention, 25% improved social interaction, and 10% resumed speech.
But as we all know, it takes more than one study to ensure that the results are accurate.
A separate study, conducted at the University of Colorado Cancer Center, explored the effects of luteolin on cell models of breast and endometrial cancer. In one experiment, the luteolin supplement blocked the increase of progesterone that promotes breast cancer. However, in the endometrial cancer cell model, the luteolin acted like an estrogen to directly stimulate cancer cell growth.
"Even outside these specific findings with cancer, what we're saying is that flavonoids are active and not always in good or even predictable ways," says Steven K. Nordeen, PhD, investigator at the CU Cancer Center and professor emeritus in the Department of Pathology at the CU School of Medicine.
He points out that "nutraceuticals" -- which include flavonoid and other active-ingredient supplements -- aren't FDA-regulated to the same degree as medicines. This allows manufacturers to market supplements without fully testing the products for efficacy or potential side effects.
"I'm not saying that flavonoids in a normal, plant-rich diet are bad," Dr. Nordeen says, "but caution is warranted when consuming additional flavonoids via supplements. Because flavonoid supplements are widely used, we need to do the research necessary to understand their effects, both desirable and undesirable, in consumers using these products. We shouldn't be taking this stuff blindly because, just like prescription medicines, there can be unanticipated consequences."
Steven K. Nordeen, Betty J. Bona, David N. Jones, James R. Lambert, Twila A. Jackson. Endocrine Disrupting Activities of the Flavonoid Nutraceuticals Luteolin and Quercetin.Hormones and Cancer, 2013; DOI: 10.10
Theoharides TC, Asadi S, Panaqiotiodou S. A case series of a luteolin formulation (NeuroProtek®) in children with autism spectrum disorders. Int J Immunopathol Pharmacol. 2012 Apr-Jun;25(2):317-23.