Eczema can be an incredibly frustrating and challenging skin condition. There's no cure. The treatments have potential side effects. And eczema is a complex condition, with different potential triggers in different people. It's no wonder, then, that many of my patients ask about dietary supplements. What have research studies determined about the effectiveness of supplements for the treatment of eczema? I co-authored a review article on this subject, written for a medical journal.
[If you're interested in the full article, link here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5006549/]
After reviewing the research in this area, I came to the conclusion that supplements fall into four main categories when it comes to their effectiveness.
Group 1: Shows promise. These may be worth trying.
Group 2: Not recommended overall, but further research is suggested in specific subgroups of patients.
Group 3: Limited research available.
Group 4: Research performed to date is either low quality or has not shown promise. At this time, not recommended.
SHOWS PROMISE
1. Probiotics and prebiotics taken together may be helpful.
Probiotics are live bacteria that are similar to those found naturally in the human body and which may be beneficial to health. They may be found in supplements or in certain foods that contain live, active cultures.
Prebiotics are foods or supplements that contain certain non-digestible ingredients that help to encourage the growth of good bacteria in our guts. Prebiotics are found in human milk, and certain prebiotics, such as dietary fiber and inulin, are found in some vegetables.
Probiotic foods that contain live, active cultures of good bacteria may be helpful for some persons with eczema
The combination of prebiotics and probiotics, called synbiotics, may be helpful in treating some patients with eczema. The most promising effects appear to be seen with a combination of different strains of bacteria and when used for at least 8 weeks in adults and children over the age of one.
While these are promising findings, more research is definitely needed. What needs to be studied further? To start with, we just don't know the optimal dose of the probiotic. We don't even know which strain or combination of bacterial strains would be most effective. Different research studies have used different doses and types of probiotics, in combination with different types of prebiotics.
Therefore, at this time, I can't recommend a particular over-the-counter supplement. To start with, though, this research certainly supports the use of foods that are naturally probiotic. This means foods that contain live, active cultures of good bacteria, such as certain types of yogurt, kefir, miso, sauerkraut, kimchi, pickles, and others. For more prebiotics, start with increasing your intake of high fiber vegetables.
NOT RECOMMENDED OVERALL, BUT FURTHER RESEARCH IS RECOMMENDED IN CERTAIN SUBGROUPS
2. Researchers have studied the use of vitamin D in the treatment of eczema. While most studies have not shown a benefit, some studies have.
There's one possible reason for these conflicting results. While most patients likely won't be helped, it's possible that certain types of patients may benefit. Further research in these subgroups is recommended.
Vitamin D has not been shown to be helpful in most patients with eczema, but further research is recommended for certain groups of eczema patients
In some of the studies, interesting results were seen in some patients with very low levels of vitamin D, those with food allergies, and those with frequent bacterial skin infections. Further research is recommended for these types of patients.
3. Evening primrose oil and borage seed oil are over-the-counter supplements that have been studied as a treatment for eczema. Both are high in an essential fatty acid.
A number of studies have now looked at these for the treatment of eczema. The results have been disappointing.
No significant differences overall were seen in the skin of eczema patients treated with these supplements as compared to the skin of patients treated with a placebo (placebos contain no active ingredients at all).
Is it possible that these would help patients with very mild eczema who don't undergo any treatment with medicated creams? We don't know. The studies done so far are in patients who were also being treated with prescription medicated creams. Therefore, we don't know if these supplements would be helpful for eczema patients who don't use any prescription medicated creams.
NOT MUCH RESEARCH AVAILABLE, BUT SINCE SOME PRELIMINARY STUDIES HAVE SHOWN PROMISE, FURTHER RESEARCH SHOULD BE DONE.
4. There's been very little research done on fish oil supplements in the treatment of eczema. There were some encouraging preliminary results, though, and therefore I'm looking out for the results of larger studies.
THE RESEARCH DONE SO FAR HAS EITHER BEEN LOW QUALITY, OR HAS NOT SHOWN PROMISE
At this time, we do not recommend Chinese herbal medicine for the treatment of eczema
5. Chinese herbal medicine (CHM) must be approached with caution. At this time, I do not recommend CHM. Some patients assume that CHM is based on herbs and therefore should be safer. However, CHM is not one specific supplement or medication. In fact, researchers have noted that some CHM may actually contain animal or mineral substances.
In one review article, researchers looked at multiple studies of CHM. They could not find evidence that CHM taken by mouth or applied to the skin was helpful for patients with eczema.
This review stated that some of the research studies were of low quality, or possibly biased, and therefore hard to evaluate. They also noted that it's difficult to study CHM, because the doses and formulations of the treatments aren't standardized and can vary quite a bit from patient to patient. It's possible that future studies may have different conclusions, but at this time I do not recommend CHM.
Dr. Rajani Katta is the author of Glow: The Dermatologist's Guide to a Whole Foods Younger Skin Diet. To receive future updates on preventive dermatology and the role of diet, sign up here.