Krill Beats Fish Omega-3s in Battling Metabolic Dysfunctions
July 2009
Omega-3s sourced from krill (a shrimp-like marine animal) are more effective than those from fish oil in combating some metabolic symptoms, including raised fat levels in the heart and liver and violent mood swings in obese individuals. So say Italian researchers following a study conducted with rats.
The study, published in the Journal of Nutrition, concludes that while both fish-sourced and krill-sourced omega-3 oils are effective in reducing fat levels, krill is more effective.
The researchers, led by Barbara Batetta, said the mechanisms of why this was the case had not been made clear in the study, but suggested long-chain polyunsaturated fatty acids (LCPUFAs) may reduce activity in the endocannabinoid system.
The endocannabinoid system consists of a group of neuromodulatory lipids and receptors that influence appetite, pain sensation, mood and memory.
“Whereas CB1 (cannabinoid receptor type 1) receptor antagonists dampen the over-activated endocannabinoid system by blocking the receptor, dietary (n-3) LCPUFA and KO (krill oil) in particular, may reduce the activity of the endocannabinoid system by decreasing the substrate availability for endocannabinoid biosynthesis,” the researchers said.
"Such a nutritional approach, if influencing the endocannabinoid system only peripherally, might avoid the adverse psychiatric effects associated with the use of CB1 antagonists, thus potentially providing a safer alternative for ‘endocannabinoid re-equilibration’ in obese individuals."
The researchers found that, when parameters associated with obesity were considered, krill oil reduced heart fat levels by 42%, compared to two percent for fish oils.
In the liver, a 60% reduction was observed for krill, 38% for fish oil. Fat build up in the liver can lead to insulin insensitivity and cause type 2 diabetes.
While the exact mechanism for change could not be isolated, the researchers stated: "It is worth noting that in all tissues exhibiting changes in endocannabinoid concentrations, EPA and DHA concentrations in the PL (phospholipid) fraction were increased and the increase was greater in the KO compared with FO (fish oil) supplemented rats."
The 18 four-week-old Zucker rats were fed either a diet of KO or FO balanced for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), or a control group with no EPA and DHA but similar contents of oleic, linoleic and a-linolenic acids. The dosage level was set at two grams of DHA/EPA per day.
Journal of Nutrition Published online ahead of print.
Here is another article of interest.
http://articles.mercola.com/sites/a...-krill-oil-48-times-better-than-fish-oil.aspx
Dan
