There are relatively few products on the market that use the AREDs formula, such as VisiVite Original Formula, Viteyes AREDS formula and Ocuvite Preservision.

Many more are formulated with lutein and zeaxanthin – and indeed the makers of Viteyes have also developed an ‘AREDS with lutein' formula. Moreover, a second AREDS study is underway to ascertain the role of lutein and other dietary nutrients, such as omega-3, in AMD.

Yet the implication from the DTB report is that consumers who plump for non-AREDS formulations could not be making the best choice.

Dr. Stuart Richer, author of the Lutein Anti-oxidant Supplementation Trial (LAST), published in Optometry in April 2004, one of the studies reviewed by DTB, said: “These recommendations ignore the established science from our laboratory and others that the nutrient lutein, among other nutrients, improves the visual function of most patients with AMD, even if these patients have only early manifestations of the disease not typically detected during standard eye examinations.”

He said that physicians have traditionally underestimated the impact of the improvements brought about by lutein on contrast sensitivity, glare recovery, night vision and driving safety, as well as their effect on the sense of well being of the patient.

Although he conceded that whether or not advanced disease can be prevented with lutein remains an unresolved scientific issue (to solve it would require a large number of patients studied over many years) from his own professional experience the indications are positive:

"The majority of my AMD patients report dramatic improvements in their visual function within a few months of increasing either spinach or lutein supplementation,” he said.

Kemin Health, the maker of FloraGLO Lutein, said in a statement that it believes the science supporting lutein and eye health to be substantial: more than 130 peer reviewed studies have been published in the past 10 years highlighting the significance of lutein in eye health.

“AREDS is an important study establishing the role of nutrition in eye health… We are confident the AREDS II study will confirm the existing body of science supporting lutein and eye health,” it said.

Ciaran Hurley, managing director of Genesis Group, which recently launched a lutein and zeaxanthin supplement under the brand name Eye-XL, said that it appears the DTB investigation was based on outdated research. LAST was one of the studies which influenced his company's decision to launch Eye-LX, in 6mg and 10mg concentrations. He also cites research of Dr Johanna Seddon of Harvard University that concluded there is a supporting a role for lutein and zeaxanthin in preventing the onset of AMD.

"We are satisfied that the evidence for our decision remains overwhelming," he told NutraIngredients.com.

Indeed, the existing evidence in support of lutein is sufficient to convince some health authorities of its value. For example, the French Safety Agency (AFFSA) authorizes a health claim connecting lutein with reducing oxidative stress in the retina.