Sea buckthorn (not to be confused with common buckthorn) is a plant native to high altitude regions of China and Russia, but today it is cultivated in many other areas, including the Saskatchewan province of Canada. The fruits of the plant have a long history of use as food. It was also used in ancient Chinese medicine for treating skin problems and digestive disorders. The whole berry or its oil extract are the parts used medicinally.

Like many other berries, sea buckthorn berries are rich in vitamin C, vitamin A, and a variety of bioflavonoids and carotenoids. However, there are no well-established therapeutic uses of this herb.

The only substantial, well-designed study of sea buckthorn examined its possible efficacy for reducing the frequency and duration of the common cold. This double-blind, placebo-controlled study of 254 people failed to find any evidence of benefit.1

The study just mentioned also found, rather incidentally, that use of sea buckthorn was associated with a reduction in C-reactive protein, an emerging marker for heart disease. However, contrary to widespread advertising, this incidental observation has no immediate practical meaning. High levels of C-reactive protein are, at present, only known to be associated with higher heart disease risk; it is not at all clear that deliberately reducing C-reactive protein will reduce heart disease risk.

In fact, one of the leading theories is that high levels of C-reactive protein indicate the presence of a bacteria that is currently unidentified but that accelerates atherosclerosis. If this theory is true, it is no doubt possible to reduce the C-reactive protein levels that indicate the bacteria’s presence without reducing the levels of the bacteria itself.

In other words, reducing C-reactive protein would only hide the signs of the problem, rather than affect the problem. Furthermore, this study was designed to look at effects on the common cold, not effects on C-reactive protein. If one conducts a study and afterwards goes on a hunt for something that is different between the treatment and placebo groups, the laws of chance alone guarantee that one will find something. This is called data-dredging, and it is a common cause of false conclusions.

To determine whether sea buckthorn actually affects C-reactive protein levels (something that itself may be altogether unimportant), one needs to conduct a study designed at the outset to examine this question. Other evidence cited to indicate that sea buckthorn can prevent or treat cardiovascular disease is similarly too preliminary to justify usage for this purpose.2-8

The traditional use of sea buckthorn oil for stomach ulcershas been tested in a few studies, but all of them are far too preliminary to be relied upon at all.9-13

Other proposed uses of sea buckthorn that lack reliable supporting evidence include reducing the side effects of cancer treatment,14-22treating liver cirrhosis,23 and aiding wound healing.24-28

An often-cited study supposedly found that a sea buckthorn extract taken orally was helpful for eczema, but in fact placebo treatment proved equally or more effective.29