In 2004, a special mixture of fats called cetylated fatty acids began to be widely marketed as a treatment for osteoarthritis. Although the claims associated with this product appear to exceed what has actually been proven, it is fair to say that cetylated fatty acids have shown definite promise in preliminary trials.



There is no dietary requirement for cetylated fatty acids.

Therapeutic Dosages

Cetylated fatty acids are used both orally and as a topical cream.

A typical oral dose of cetylated fatty acids is 1,000 to 2,000 mg daily. Cetylated fatty acid creams are applied two to four times daily to the affected area.

Therapeutic Uses

Three double-blind, placebo-controlled studies have found cetylated fatty acids helpful for osteoarthritis]]> . Two involved a topical product, and one used an oral formulation.

In one of the studies using that used a cream preparation, 40 people with osteoarthritis of the knee applied either cetylated fatty acids or placebo to the affected joint. ]]>1]]> The results over 30 days showed greater improvements in range of motion and functional ability among people using the real cream than those using the placebo cream.

In another 30-day study, also enrolling 40 people with knee arthritis, use of cetylated fatty acid cream improved postural stability, presumably due to decreased pain levels. ]]>2]]>

In addition, a 68-day, double-blind, placebo-controlled study of 64 people with knee arthritis tested an oral cetylated fatty acid supplement (the supplement also contained lesser amounts of ]]>lecithin]]> and ]]>fish oil]]> .) ]]>3]]> Participants in the treatment group experienced improvements in swelling, mobility, and pain level as compared to those in the placebo group. Inexplicably, the study report does not discuss whether or not side effects occurred.

While this is a promising body of research, it is far from definitive. Current advertising claims for cetylated fatty acids go far beyond the existing evidence. For example, a number of websites claim that cetylated fatty acids are more effective than ]]>glucosamine]]> or ]]>chondroitin]]> . However, no comparison studies have been performed upon which such a claim could be rationally based.

It's not known how cetylated fatty acids might help osteoarthritis. Proponents cite the known benefits of ]]>fish oil]]> for ]]>rheumatoid arthritis]]> , but since the fatty acids in fish oil are rather different from those in cetylated fatty acids, and the origin of rheumatoid arthritis is quite unlike that of osteoarthritis, there is little relevance to these observations. Proponents also make multiple specific claims, including that cetylated fatty acids reduce inflammation, protect cartilage from damage, lubricate cell membranes, and increase fluid in joints. However, none of these explanations have more than speculative scientific support. At present, if in fact cetylated fatty acids help osteoarthritis, we do not know how they might do so.

Cetylated fatty acid creams have also been proposed for treatment of ]]>psoriasis]]> . ]]>4]]>


Safety Issues

Cetylated fatty acids appear to have a low level of toxicity, according to safety studies conducted by the primary manufacturer. 5-7]]> However, maximum safe doses in young children, pregnant or nursing women, or people with severe liver or kidney disease have not been established.