Whole Foods pulled krill oil products off its shelves recently, citing declines of certain populations of animals relying on krill to survive. Krill are tiny relatives of shrimp, about half an inch long. A rich source of omega-3 fatty acids, they also occupy a key position near the bottom of the highly fragile oceanic food chain and represent the largest animal biomass on the planet. This made them seem a likely sustainable source for the much-coveted ingredient and a buffer against the huge ecological disasters wrought by overfishing.
But the decline of animal populations that rely on krill apparently told a different story. In response to concerns over management of this natural resource, the Commission for the Conservation of Antarctic Living Marine Resources, a multinational treaty organization managing krill fisheries, issued a report changing quotas and restricting fishing areas.
Thousands of studies over several decades give strong evidence that omega-3s can help keep the cardiovascular system healthy while protecting against cancer and birth defects and countering symptoms of diabetes, arthritis, cognitive decline, depression and a number of other diseases. And while the entire gamut of omega oils have proven to be beneficial to health and wellness, some researchers point to the stark imbalance of dairy- and meat-derived omega-6 intake to omega-3 intake as a key component in the seemingly intractable pandemic of obesity and related diseases.
Consumption of omega-6 fatty acids in the American diet have increased multifold at the expense of omega-3 intake. (Omega-9 fatty acids, from olive oil and canola oil, also have a wealth of positive health effects but are easier to come by in the American diet.)
A key difference between krill oil and fish oil is that the former carries much (about two-thirds) of its omega-3 fatty acids (eicosapentaenoic acid, or EPA, and docosahexaenoic acid, DHA) in compounds called phospholipids, which are structural or membrane fats. In fish oil, the vast majority of omega-3s are carried in triglycerides or stored fats. About 95 percent of dietary fats are triglycerides, which characteristically have three fatty acids per molecule—tri-glycerides. Phospholipids carry two. In fish oil concentrates, the triglycerides are converted to ethyl esters where the fatty acids are linked to ethanol.
Some vendors claim the phospholipid form is better absorbed than the triglyceride form, but there's not enough research to support the claim. Moreover, the body doesn't absorb these molecules intact. During digestion, the fatty acids are clipped off both triglycerides and phospholipids and reformed once absorbed into the cells. So whether it's from fish oil or krill oil, the fatty acids are the same.
Plant-sourced omega-3 fatty acids have gained ground as an ecologically sound alternative. But those omega-3s are in the form of alpha-linolenic acid (ALA). Your body converts ALA to EPA and DHA, but it's not very efficient, converting only about 5-10 percent of the ALA. Of course it's important to remember that ALA is still an omega-3, an essential fatty acid, and it's not established that EPA and DHA are essential as long as you have a source of ALA. It's just that EPA and DHA appear to have some desirable affects that we are not certain can be duplicated by depending upon our innate ability to convert ALA into those compounds.
So if krill are off limits, and fish oil is in danger of being seen as a finite resource, how can processors expect to meet the ever-burgeoning demand for omega-3s? Here's where the good news comes in.
A rush to develop more sustainable sources of EPA and DHA drew attention to algae, which naturally contain EPA and DHA. In fact, the omega-3s from krill and fish originate from the algae consumed by them or the creatures they feed on. Not only sustainable, algae can be farmed, and this form allows for such desirable labels as "vegetarian," "kosher" and even "organic."
Algae-derived omega-3s are already on the market, although typically as a supplement. Columbia, Md.-based Martek Biosciences Corp., now a part of DSM (www.dsm.com), Parsippany, N.J., makes its lifesDHA (www.lifesdha.com) from specially grown and purified microalgae. The product is now in wide use in products such as fruit juices, milk, soy milk, cooking oil, sauces and even tortillas. Processors can soon expect to see sufficient and increased availability of algae-based omega-3 fatty acids suitable for food and beverage applications that will allow them to increase these offerings and bring a truly sustainable source of beneficial omega-3s to consumers.