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GLA: The ‘Good’ Omega 6

Gamma linolenic acid (GLA) oils, namely evening primrose, borage and black currant oils, have a long history of use as dietary supplements, and as the body of research on GLA’s efficacy grows, demand will continue to increase. GLA is an omega 6 fatty acid, a metabolite of linoleic acid. Despite its popularity, there is very little published information on consumer perceptions of GLA. In order to understand why consumers purchase these types of oils, Life Sciences Alliance, Moraga, CA, conducted comprehensive consumer research to find out more about current consumers’ purchase behavior, drivers and decision making for GLA products. (The results, developed in 2005 during a client engagement, are now allowed to be published with their permission.)

This research combined quantitative and qualitative consumer research. The results are indicative of U.S. consumers’ perceptions and attitudes; however, as with all qualitative studies, broad generalizations are to be approached carefully.

Biological Effects of GLA

The physiological effects of GLA have been studied for several decades. Young, healthy individuals synthesize GLA from the linoleic acid (LA) in their diets. However, several sources of evidence strongly suggest that normal aging and multiple dietary and disease conditions may interfere with this bioconversion, and/or may reduce body pools of GLA metabolites, such as dihomogamma-linolenic acid (DGLA). This is why GLA is considered a conditionally essential dietary fatty acid that may provide some health benefit.

Supplementation of the diet with GLA (0.3 g – 1.5 g/day) leads to increased levels of the metabolite DGLA in membrane phospholipids. Levels of arachidonic acid (AA) may or may not increase after GLA supplementation, depending upon the dietary intake of long-chain omega 3 fatty acids, which compete with AA for membrane incorporation. DGLA and AA are precursors of several types of eicosanoids involved in inflammation. While eicosanoids derived from AA are primarily pro-inflammatory, eicosanoids derived from DGLA may have anti-inflammatory effects. Thus, GLA has been proposed to potentially mediate numerous health and disease states, including PMS, arthritis, skin health, diabetes and cardiovascular health (Horrobin, 1992).

GLA Sources

A typical western diet contains very low amounts of GLA. The most concentrated sources of GLA come not from traditional foods, but rather oils from seeds and microorganisms (Gunstone, 1992). Commercialized plant seed oil sources include borage (Borago officinalis), evening primrose (Oenothera biennis) and black currant (Ribes nigrum). Microorganisms that produce GLA include cyanobacteria (Spirulina maxima and S. platensis) and fungi (most important species are Mucor javanicus and Mortierella isabellina). None of these concentrated sources of GLA are present in a typical diet, but the oils can be consumed in dietary supplement form. Other sources of GLA in development include Echium oil (Phillips and Huang, 1996), and biotechnology-derived safflower oils and canola oils (Flider, 2005; Wainwright et al., 2003). See Table 1.

Table 1
Concentrated Sources of GLA
Current Sources GLA, Weight % of Fatty Acids
Black Currant 15-20
Borage 20-25
Evening Primrose 8-14
Mortierella 3-8
Mucor 15-18
Spirulina 18-21
Potential Future Sources GLA, Weight % of Fatty Acids
Echium Oil 10-11
GLA Canola 36-40
GLA Safflower 35

The Market for GLA Oils

The current retail market in the U.S. exceeds $100 million and is highly fragmented by end product marketer, type of oil, health benefit positioning, etc. The major sources of GLA—evening primrose oil (EPO), borage oil and black currant oil—are all primarily sold into the retail dietary supplement market in the form of refined oils in softgel capsules. While reliable data is very hard to obtain, the total global production of evening primrose oil, mostly from Chinese sources, is estimated at 1000-2000 metric tons (Lapinskas, 2000) annually at a bulk price of around $10-15 per kilogram. Borage production, largely in the U.K., with smaller quantities produced in Holland, Canada and New Zealand, is about 50% smaller in volume, but the bulk selling price is higher at $30-35 per kilogram mainly due to higher GLA concentration. The ingredient market ranges between $25-$65 million annually. The broad range of volume estimates is more than five years old, however, anecdotal information suggests that demand has increased in the intervening period. The value of the ingredient sales simply provides an estimate of the “macro” size of the market.

There are numerous brands of EPO and borage oil capsules on the market. While some brands carry both types of oils, others sell only one or the other. A nonscientific sample of products from California pharmacies found EPO products ranging in price from $6.49 to $22.99 for 50-60 softgels. Prices for borage oil were more consistent, in the $15-$20 range for 60-100 softgels.

A review of the current products’ labeling indicates there is no consensus regarding adequate or recommended doses of GLA, which range from approximately 90 mg to 1000 mg per day. Further, GLA oil products bear a wide variety of different structure function (S/F) claims. See Table 2 below.

Table 2
Examples of Dosing Recommendations & Structure/Function (S/F) Claims
Brand & Oil GLA Per Softgel Serving Size & Recommended Frequency Recommended GLA Daily Dose
Health State Mentioned in S/F Claim
Nature’s Bounty 90 mg 1 softgel (1-3 times daily) 90-270 mg Prostaglandin Precursor
Barleans (EPO) 130 mg 2 capsules (once daily) 260 ml PMS, Menopause
Health from the Sun 300 mg 1 softgel (once daily) 300 mg Healthy Skin, Flexible Joints
(Borage Oil)
Natrol 500 mg 1 softgel (1-2 times daily) 500-1000 mg Cardiovascular Health
(Borage Oil)

GLA Consumer Research & Results

To find out more about consumer purchase behavior as it relates to GLA oil products, Life Sciences Alliance conducted a multi-phase, consumer market research program to address this need.

The first phase included a telephone survey of 1000 randomly chosen U.S. households. The survey was conducted by a prominent market research agency and utilized questions with category scale responses. The sample was balanced to be representative of the continental U.S. based on region, population density, household income, household size and household type. The results were weighted, using the Current Population Survey from the U.S. Census Bureau to give appropriate representation on various demographic factors, including gender, age, income and region.

Based on incidence data from the telephone survey and the 2000 U.S. Census data, we estimate that approximately six million adults purchase GLA oil products. Two-thirds buy EPO, while the remainder primarily purchases borage oil.

Consumers of GLA oil products are predominantly female by a ratio of 2:1, 70% of which use EPO. Males are evenly split, using both borage and evening primrose oils. GLA oil products are used at a similar incidence across most major demographic criteria (region, household income, marital status). Adults of all ages use GLA oil products—the data contained no strong age-related skew.

Consumers are purchasing their GLA products in multiple locations. Almost half buy at mass merchandise stores like as Wal-Mart or Target. Forty-two percent purchase at health food stores. One-third of consumers purchase GLA products at drug stores or pharmacies. Approximately 25% are making purchases online, via mail order or at a grocery store.

Focus Group Research & Results

We used the information from the telephone survey to plan a series of four focus groups in San Francisco, CA, and suburban Chicago, IL. The person who functioned as focus group moderator had experience in the nutrition/dietary supplement industry. Participants were prescreened to match the demographics determined from the telephone survey. The purpose of the focus group was to elicit individual comments and promote group discussion of respondents’ current usage patterns, knowledge of GLA products, health benefits, label claims and purchase drivers. Respondents brought in the products they use, but we also supplied each group with numerous examples of products to facilitate comparisons of recommended dosing, label claims and brands. We also probed how they obtain information and whom they consider influencers. Finally, we presented a series of product concept pairs for respondents to choose between to elicit dialogue on what factors are important regarding intake, dosage, cost and names.

Among the GLA oil respondents, physicians are not viewed as adequate sources of information about dietary supplements, leading consumers to seek information elsewhere. Opinions of popular health gurus obtained from newsletters or websites, as well as friends and family are more respected. Males (77%) are more likely than females (44%) to consult the Internet for information about dietary supplements. Typically consumers visit and consult more than one Internet site for supplement recommendations.

In spite of trying to educate themselves, the focus group respondents were not adequately informed. More than 50% did not know that GLA is the active ingredient in borage and evening primrose oils. There was wide divergence of knowledge about dosing and response to supplementation. Some believe that the benefit “washes out” with water. Even more startling, some believed that the benefit is immediate. Several respondents said that they take more on a “bad day” which should have no impact beyond a placebo effect. Finally, some respondents were satisfied with low GLA dose products, while others looked for the highest dose products available.

While many of the respondents consumed a multitude of dietary supplements, they expressed many distrustful comments regarding the industry in general. They also distrust labeling claims, which many view as exaggerated.

Despite their distrust of the industry, we observed a willingness to be influenced. When presented with information on GLA as the active ingredient in EPO and borage oils, for example, consumers readily chose between different product concepts based on GLA content, usually preferring those with higher GLA levels, particularly if these represented a better value (more GLA per dollar spent). However, some respondents were wary of products with high levels of GLA, believing that they may have undesired side effects.

The respondents in these studies also claimed to highly value “naturalness,” but at the same time remained interested in products with an attractive brand name and label with competitive price. Naturalness seemed to be a secondary factor in their purchase decisions. The primary purchase driver is number of capsules recommended for effective dosage per day, with 1 pill per day being the overwhelming consumer preference. Also with most consumers, price and a trustworthy brand name are key factors to consider.

Consumers were also asked why they use GLA products. Most listed more than one reason. In order of prevalence, those reasons included:

83% Improve general health
52% Reduce inflammation
44% Reduce joint or other body pain
44% Improve the appearance of skin
28% Reduce eczema, dermatitis or itchy skin
28% Reduce effects of PMS
12% Reduce diabetic neuropathy
4% Other: e.g. heart health, cancer prevention, yeast infection, menopause symptoms

On the Horizon

Higher concentrations of GLA in an enriched oil might enable consumer intake of beneficial doses in as few softgels as possible, one softgel daily being the ideal. Production efficiencies might also reduce the cost per effective dose, benefiting both manufacturers and consumers.

Consumers definitely need additional, factual information about GLA, as well as recommended GLA dosing levels for specific health states in order to make fact-based decisions about GLA product offerings. To the extent allowable by law, the industry should make a concerted effort to provide this information. Since many GLA consumers use the Internet, consumer-friendly information should be made available online to help them through this education process. This presents an opportunity to position GLA per se as a healthy fatty acid, rather than focusing on the similarities and differences between EPO and borage oil.

About the authors: Dr. Julianne Lindemann, principal of Life Sciences Alliance, Moraga, CA, can be reached at 925-377-0790; E-mail: [email protected] Alexander Merolli, principal and co-founder of Life Sciences Alliance Pleasanton, CA, is also a member of Stratecon International Consultants. He can be reached at 925-462-7428; E-mail: [email protected]

References furnished upon request.
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