Research Mounts on Benefits of Omega-3s

Two recent studies from the Archives of Neurology suggest that omega-3 fatty acids may be helpful for people suffering from cognitive decline. The studies, while not definitive, add more support to the theory that the omega-3s docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are important elements of cognitive health and well-being.

DHA AND EPA

About half of the dry-weight portion of the brain consists of lipids, and a little more than a third of that content consists of polyunsaturated fatty acids like DHA and EPA, explains David Cai, PhD, senior scientist at Cognis Nutrition and Health (La Grange, IL), which recently acquired omega-3 manufacturer Napro Pharma AS (Brattvaag, Norway).

“Along with the omega-6 fatty acid arachidonic acid, DHA is a major constituent of neuronal membranes, making up about 20% of the brain’s dry weight,” Cai says. “Synapses contain a high concentration of DHA, which appears to play a role in synaptic signal transduction. DHA is also important for normal cognitive development. In addition, the antiinflammatory compounds that DHA is a precursor for may function in the brain to protect against ischemic damage.”

Polyunsaturated fatty acids generally play important roles in the structural and functional maintenance of neuronal membranes, neurotransmission, and eicosanoid biosynthesis, Cai adds. Other important activities omega-3s are involved with include modulating ion channels, receptors, and ATPases, and maintaining membrane fluidity and flexibility.

Omega-3 deficiencies or imbalances may be related to a variety of cognitive and mental health conditions. Research in animals and humans has prompted several theories about the relationship between omega-3s and disease. “One mechanism linking fatty acids and cognitive function or dementia may be atherosclerosis and thrombotic events,” Cai says. “Inflammation is another mechanism that may explain the role that omega-3 fatty acids play in dementia. Research has also shown these fatty acids to be important in human infant visual development.”

ARCHIVES OF NEUROLOGY

The first study, conducted by researchers from Karolinska Institutet (Stockholm) and Uppsala University (Uppsala, Sweden), appeared in the October 2006 issue of Archives of Neurology. In the study, the researchers examined the effects of omega-3 supplements on the rate of cognitive decline in people with Alzheimer’s disease who were being treated with acetylcholine esterase (ACE) inhibitors. For six months, 85 patients received a placebo and 89 patients received EPAX (Lysaker, Norway) 1050 TG supplements containing 1.7 g of DHA and 0.6 g of EPA. During an additional six-month period, both groups received the omega-3 supplements. The researchers tested the cognitive abilities of the patients at the beginning of the study and after six and 12 months.

Expansion Predicted for Asian Omega-3 Market

Rising consumer demand pushed revenue for the Asia Pacific omega-3 market to $279.6 million in 2005, according to Frost & Sullivan (London). The research firm predicts that sales could reach $596.6 million by 2012.

“Wider media coverage of omega-3 highlighting its numerous health benefits, together with supporting scientific evidence, is increasing overall consumer awareness of the ingredient,” according to Vignesh Raja, a research analyst at Frost & Sullivan. “Mainstream media such as television, radio, print, and the Internet have repeatedly underlined the importance of including omega-3 in diets.”

Frost & Sullivan warns, however, that an uncertain regulatory environment in the region could put a damper on sales. Only Australia, New Zealand, and Japan have recommended daily intakes for EPA and DHA. Consumer awareness of omega-3s is higher in those three countries. One sign that demand in the region is on the rise is Ocean Nutrition Canada’s (Dartmouth, ON, Canada) recent announcement that it has hired new personnel to lead its Asian expansion. The company also plans to open an office in Shanghai this year.

“Australians and New Zealanders are among the healthiest people in the world, and the entire region has a very high awareness of omega-3 health benefits,” says Ian Lucas, executive vice president of global sales and marketing at Ocean Nutrition Canada. “The Asian markets, in particular, are very conscious of the specific brain health benefit of DHA, one of the omega-3 fatty acids that is essential to brain development in children.”

While there was no difference in the rate of decline between the two groups after six months, the researchers did notice that in a subgroup of 32 patients who had very mild cognitive impairment at the beginning of the study, those who took the omega-3 supplements showed less decline than those who took the placebo. Moreover, in the entire placebo group, decline decreased during the second six months after everyone began taking the omega-3s.

Yvonne Freud-Levi, MD, a psychiatrist at the Karolinska Institutet and the study’s lead author, called the results “positive and rather unsuspected,” noting that the omega-3s seemed to complement the effects of ACE inhibitors, which do not inhibit memory decline. “We are now starting to realize the importance of DHA in the brain as being not only a structural component of brain cells, but moreover, a natural compound guarding the aging brain cells from degradation by neurotoxic mechanisms,” Freud-Levi said.

But Jan Palmblad, MD, chief of the Karolinska Institutet’s hematology division and another study author, cautioned against using the study’s findings as a basis for making general recommendations about DHA as a treatment for Alzheimer’s disease. “Studies in larger cohorts with mild cognitive impairment, including those at risk for Alzheimer’s disease, are needed to further explore the possibility that omega-3 fatty acids might be beneficial in halting initial progression of the disease,” he said.

The second study did not look at the effects of omega-3 supplements, but, rather, the relationship between levels of DHA in the blood and dementia. In that study, which appeared in the November 2006 issue of Archives of Neurology, Ernst Schaefer, MD, and colleagues from USDA’s Human Nutrition Research Center on Aging at Tufts University (Boston) tracked 899 elderly participants of the Framingham Heart Study for an average of nine years. The volunteers, who did not have dementia at the beginning of the study, gave blood samples and received mental evaluations. In addition, a subgroup of 488 volunteers filled out a questionnaire about their diet.

New Omega-3 Trade Association to Champion High Quality Standards

Promoting consumer education, regulatory approvals, and higher quality standards is at the top of the agenda of the new Global Organization for EPA and DHA (GOED), according to Baldur Hjaltson, a member of GOED’s board of directors.

Education is a key component of GOED’s strategy. “Consumers are not always aware whether omega-3 fatty acids are coming from marine oils or from flaxseed oil,” Hjaltson says. “The health benefits are quite different, and it is important to educate the consumer.”

Hjaltson adds that increasing market and regulatory approvals around the world for omega-3 products is another goal for the new group. “It is important that more health claims will be allowed for EPA and DHA marine oils,” Hjaltson says. “This is best done by working together in an organization such as GOED. Also, it’s important for government agencies to set up recommended daily intakes for EPA and DHA so consumers will know how much of these important fatty acids they need on a daily basis.”

GOED also intends to develop quality standards to improve consumer confidence in marine oils, adds Hjaltson. “In Europe, there are several monographs in the EU pharmacopeia describing the quality of marine EPA and DHA fish oil, while in the United States there is only the voluntary monograph on fish oil,” Hjaltson says. “GOED will work on improving quality and help government agencies set quality standards for EPA and DHA omega-3 products.” He adds that official methods for analyzing the potency of omega-3 products are another important piece of the puzzle.

“The most important thing is to develop high quality standards that the industry can follow,” Hjaltson says.

During the nine years of the study, 99 participants developed dementia. After dividing the study participants into four groups based on their plasma phosphatidylcholine (PC) DHA levels, the researchers determined that those in the highest quartile had a 47% lower risk of developing dementia and a 39% lower risk of developing Alzheimer’s disease. Using the diet questionnaire, the researchers also were able to calculate that the average intake of DHA in the top quartile was 0.18 g per day.

Like the researchers who conducted the Swedish trial, the Tufts researchers cautioned that more research is needed to verify the findings. “In the future, it will also be important to determine whether combined dietary supplementation with DHA can decrease further mental deterioration in patients with established dementia,” they wrote. Still, the Tufts study is noteworthy because it is the first prospective analysis to assess the predictive value of plasma PC DHA, a more accurate measurement of dietary intake of omega-3 fatty acids than nutrient analysis of dietary records.

Despite their limitations, both studies provided valuable data about the potential benefits of omega-3s. Manufacturers are eagerly awaiting the results of new studies to come. “Looking to the future, we’d like to see studies of longer duration to build on these exciting results,” says Cognis Nutrition and Health’s Cai. “All studies that assess the effects of omega-3 fatty acids should use standard validated instruments to assess clinical outcomes.”

New Omega-3 Product Introductions Feature Innovative Ingredients

As consumer interest in omega-3 builds, so does the pressure for novel products. Several of the latest omega-3 items combine multiple ingredients for a synergistic effect.

In December 2006, Odwalla Inc. (Half Moon Bay, CA) added DHA-enriched Odwalla Soy Smart to its family of healthy beverages. Available in chai, chocolate, and vanilla flavors, each serving of Soy Smart contains 6.25 g of soy protein along with 32 mg of life’sDHA, an omega-3 ingredient supplied by Martek Biosciences Corp. (Columbia, MD). Unlike many other sources of DHA, life’sDHA is produced from microalgae, which makes it acceptable for vegetarian products.

Another new product, EuroPharma’s (Green Bay, WI) Vectomega, is a natural marine complex made of phospholipids, DHA, EPA, proteins, and amino acids. In September 2006, EuroPharma selected New Chapter (Brattleboro, VT) as the exclusive distributor for Vectomega in the health food and natural products retail channel.

According to Lisa Joski, spokesperson for EuroPharma, Vectomega’s phospholipids are obtained through vectorization, a patented process that uses hydrolysis, rather than solvents or heat, to extract omega-3s from fish. Phospholipids enable the transport of DHA and EPA to cellular membranes. “Vectomega is the first product containing fish phospholipids extracted and left in their natural state, without the use of organic solvents,” Joski says.

Joski adds that the process also renders Vectomega highly bioavailable. “Bioavailability depends essentially on the oil’s composition of fatty acids, and especially on their location on the glycerol molecule,” Joski explains. “DHA and EPA in marine oils are generally located on the central position (sn-2) on the triglycerol molecule. This is the most advantageous position for maximum bioavailability. Our unique method of processing maintains this natural state.” According to Joski, assimilation tests carried out on Caco-2 cells, an in vitro model for small intestinal absorption, showed that Vectomega was more bioavailable than other fish oils.

New Chapter’s retail launch of Vectomega could shake up the industry, Joski predicts. “The standard fish oils on the marketplace today undergo rigorous processing and refining, and such processing changes chemical structure and composition,” Joski says. “The DHA and EPA are no longer in the sn-2 position on the triglycerol molecule, and thus are poorly absorbed. Current products in the marketplace are not inadequate. They do, however, require consumers to take extremely high amounts of capsules in order to achieve therapeutic results. With the launch of Vectomega, consumers will receive benefits while only needing to take 1–2 capsules daily instead of 9–16 or more.”