Nutrition page 3Fish Oil The brain is very choosy when it comes to the type of fat it needs. A particular type of fat called docosahexaenoic acid, or DHA for short, has received a lot of attention. DHA is type of omega-3 polyunsaturated fat, and is present in high concentrations in the brain (and eyes, particularly in the retina). DHA is found within both the neuronal membrane and myelin, so it will influence how neurons form synapses and their ability to communicate with each other. DHA also acts as an antioxidant, protecting neurons from free radical damage. Omega-3 fatty acids have also been found to protect blood vessels, including those that supply the brain, and may protect us from the loss of brain functions due to stroke. Research has begun to uncover the benefits of omega-3 fatty acids such as DHA on brain health. A number of studies have found that low levels of omega-3 may be linked to some conditions that affect the brain including attention deficit (hyperactive) disorder (ADD/ADHD), depression, schizophrenia, and dementia. Other studies investigated the beneficial effects of dietary omega-3 supplementation on these conditions, as well as other benefits including improved cognitive ability, memory, attention, concentration in children. Just like the brain, our eyes also require omega-3 fats for them to function properly. As mentioned earlier, our eyes are made up of neurons. It may be helpful if you think of them like a specialised extension of the central nervous system responsible for detecting light, translating it into electrical signals, and sending messages to the brain for processing via the optic nerve. Like the brain, eye neurons need omega-3 fatty acids like DHA which is incorporated within cell membranes and myelin. The retina (which detects light) is especially rich in DHA, needing a constant supply to maintain itself. If you or your child’s diet is low in omega-3 fats, you may both suffer poor vision. Over time, lower omega-3 fats can result in the accumulation of free radical damage, increasing your susceptibility to retinal damage, with the potential to degenerate into an eye disease. Immune system activity is partly controlled by a group of polyunsaturated fats called eicosanoids. There are two types of eicosanoids: the omega-6, and omega-3. In general, omega-6 facilitates immune cell activity, while omega-3 regulates immune cell activity. The omega-6 and omega-3 eicosanoids are synthesised from their respective polyunsaturated fats, the omega-6 and omega-3 fats. It is important that omega-6 and omega-3 eicosanoids are generated appropriately to allow the body to respond to harmful pathogens. While higher omega-6 eicosanoid activity may seem appealing, in some autoimmune disorders and allergies, too much omega-6 and not enough omega-3 eicosanoids can increase the severity of the disease, stimulating immune cells to destroy your own body tissue. The relative amount of omega-3 and omega-6 eicosanoids produced by our bodies is partly determined by our diet. The Western diet is usually high in omega-6 (usually derived from plant oils, such as corn and canola/rapeseed) and low in omega-3 (primarily from oily fish and some plants). In particular, heavier omega-3 fats such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) found in oily fish have promising potential in treating conditions where the immune system has gone awry, such as asthma, and rheumatoid arthritis. Docosahexaenoic acid (DHA) and to a lesser extent eicosapentaenoic acid (EPA), are the most highly investigated omega-3 fatty acids, and are associated with many health benefits, some of which we may not be aware of as yet. What we do know is that omega-3 fatty acids are essential for healthy nutrition. Oily fish (tuna, salmon, sardines, trout, mackerel) and oil derived from some plants including flaxseed and linseed are packed full of omega-3 polyunsaturated fats like EPA and DHA. Omega-3 fortified products such as eggs, bread and dairy products are also becoming widely available, being another good source of omega-3 fatty acids. Antioxidants Like the rest of the body, antioxidants protect our eyes from damage by free radicals as we age. In fact, people that maintain low levels of antioxidants are more likely to develop eye conditions including macula degeneration, which is one of the major causes of blindness. Individuals with low blood levels of antioxidants are generally more susceptible to health problems and less resistance to pathogens. Commonly known antioxidants include vitamin A, B, C, E, lutein and beta-carotene, iodine, zinc and fish oil. Antioxidants are highly prevalent in fruit and vegetables, nuts, fish, meat. Heating, cooking, freezing, and drying processes may destroy some of these nutrients. Micronutrients All micronutrients are essential for good health, however there are some that have key roles when it comes to brain, eye and immune health and function.
|
You need Flash Player 8 and a browser with javascript enabled to view this.
 |