Research just published in the journal Behavioral Neuroscience provides evidence that adequate omega-3 fatty acids are needed for healthy nervous systems. That could explain why low levels of omega-3s are associated with the information processing difficulties experienced by people with bipolar, obsessive-compulsive, and attention-deficit hyperactivity disorders; schizophrenia; Huntington's disease and other illnesses affecting the nervous system. What's more, this research suggests that increasing dietary omega-3s may be a natural way to prevent and treat those conditions.

Scientists at the Laboratory of Membrane Biochemistry and Biophysics at the National Institute on Alcohol Abuse and Alcoholism studied two forms of omega-3 essential fatty acids found in certain foods including fatty fish and some algae: docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The human body can only acquire these key nutrients by metabolizing their precursor, linolenic acid (LNA), or from foods or dietary supplements with DHA and EPA in a readily usable form.

EPA has been shown in numerous previous studies to have anti-inflammatory and cardiovascular protective effects. DHA, although less studied, is also crucial to the body. In fact, it makes up more than 90 percent of the omega-3s in the brain, retina and the nervous system.

For their study, the research team fed four groups of pregnant mice and their offspring four different diets with no or varying types and amounts of omega-3s. Then, after the newborn mice grew into mature animals, the scientists recorded how they responded when exposed to a sudden loud noise.

This classic test of nervous-system function normally makes healthy animals flinch. However, if animals with a normal nervous system are exposed first to a softer tone before the loud one, they flinch much less. Scientists believe that's due to an adaptive process known as sensorimotor gating which causes an initial stimulus to prepare the body for future stimuli.

The results of the tests showed that only the mice raised on DHA and EPA, but not their precursor of LNA, demonstrated normal, adaptive sensorimotor gating. These healthy animals responded in a significantly calmer way to loud noises if they had first heard softer tones. The mice in all other groups, however, were startled almost as much by the initial soft sound as by the loud noise that followed.

The reason? The scientists concluded that when DHA was deficient the nervous system was in an abnormal state that left the animals almost constantly startled and easily overwhelmed by sensory stimuli. "It only takes a small decrement in brain DHA to produce losses in brain function," lead researcher Norman Salem Jr., PhD. said in a statement to the media.

The researchers think this important information may be very significant for humans -- because weak sensorimotor gating is a hallmark of many nervous-system problems including Huntington's disease, schizophrenia and bipolar disorder. And they've suggested that omega-3s could have therapeutic potential for these and other diseases marked by nervous system problems.

Moreover, the research underlines the dangers of the typical American diet of processed foods and lots of meat -- making it far higher in omega-6 fatty acids than omega-3s. That imbalance reduces the body's ability to incorporate omega-3s and, as a result, "we have the double whammy of low omega-3 intake and high omega-6 intake," stated Dr. Salem. "It is an uphill battle now to reverse the message that 'fats are bad' and to increase omega-3 fats in our diet."

Source:

New Study Links DHA Type of Omega-3 to Better Nervous-System Function