• Regulating cholesterol levels – Those who have a Mediterranean diet have high levels of HDL (the good cholesterol), which in turn promotes cardiovascular health. The Inuit, whose diet primarily consists of fish that is rich in Omega-3, also have high HDL cholesterol, as well as lower triglycerides (fat in blood) in their system. Various clinical studies indicate that fish oil supplements, which are rich in Omega-3, significantly lower triglyceride levels in the body. Walnuts, nuts that contain a lot of alpha linolenic acid (ANA) (a substance that gets converted to Omega-3 by the body once digested), are known to lower both the cholesterol and triglyceride levels in humans, even those who have a history of having high cholesterol.
• Regulating blood pressure – Clinical studies also indicate that Omega-3 can significantly lower the blood pressure of people, particularly those who have hypertension. Seventeen clinical studies saw participants taking fish oil supplements. The results showed that taking 3 grams of fish oil or more every day can reduce blood pressure, including those who have untreated hypertension. However, taking a high dosage of fish oil such as this should be done under the supervision of a doctor.
• Preventing heart disease – As mentioned earlier, Omega-3 is known to prevent heart disease. One of the best ways to avoid cardiovascular disease is to follow a diet that doesn’t have too much saturated fat and while having plenty of monounsaturated as well as polyunsaturated fats (including those that have high levels of Omega-3 fatty acids). Furtermore, clinical studies indicate that eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two kinds of Omega-3 fatty acids in fish oil, can lower the risk of heart diesease, including high blood pressure and high cholesterol. Studies have also indicated that fish oil can greatly lower the triglyceride level, as well as to lessen the risks of having a stroke, heart attack, and heart arrhythmia (which is usually experienced by those who already experienced having a heart attack), and even death. Clinical evidence also suggests that fish oil can prevent and even treat atherosclerosis, or the hardening of the arteries, by slowing down the formation of plaques and blood clots that clog the arteries.

Studies involving large populations indicate that following a diet that’s rich Omega-3 fatty acids, particularly the consumption of fish, can help prevent stroke due to plaque buildup as well as arterial blood clots, which can reduce the amount of oxygen going into the brain. Eating 2 servings of fish or more weekly can prevent you from having a stroke by 50% or more.

• Diabetes – Diabetic patients are known to have low HDL levels and high triglycerides. Omega-3 fatty acids, particularly those in fish oil, can reverse this, lowering the amount of triglycerides while boosting HDL levels, which can go a long way in improving the health of diabetic patients. ALA, a kind of Omega-3 fatty acids which is found primarily in flax seed, while effective, is not as powerful as the Omega-3 fatty acids found in fish oil, particularly for diabetes patients, as they are unable to convert ANA into a form of Omega-3 that their body can actually utilize. Do note that some patients who have Type 2 Diabetes can experience a spike in their blood sugar levels when they take fish oil, so be sure to consult with your doctor before taking the supplement.
• Osteoporosis – Clinical studies indicate that Omega-3 can boost the amount of calcium in your body, thereby improving bone strength. Other studies indicate that those who don’t receive enough healthy fatty acids in their system (such as EPA and gamma-linolenic acid, a type of Omega-6 fatty acid) are more prone to experiencing bone loss compared to those who regularly intake these fatty acids. A clinical study with women who have osteoporosis and are over 65 years old as participants showed that those who took supplements containing EPA and GLA experienced less bone loss in a span of 3 years compared to the participants taking placebo drugs. Furthermore, the former had higher bone density compared to the latter.
• Depression – To date, studies have mixed results when it comes to the role of Omega-3 fatty acids in depression. Some studies showed that patients who took supplements rich in Omega-3 alongside prescription anti-depressants improved greatly compared to those who only took antidepressants. Other studies indicated the possibility of Omega-3 fatty acids helping protect women from experiencing postpartum depression. Because of the seriousness of depression, its important that you don’t attempt to treat the condition by yourself. Instead, its advised that you consult with a physician to help you recover from this illness.
• Attention deficit/hyperactivity disorder (ADHD) – Some studies indicate that children with ADHD actually have low amounts of fatty acids in their system. A research that saw almost 100 boys as participants showed that those who have low levels of Omega 3 fatty acids had more behavioral and learning problems, including sleep problems and temper tantrums, compared to those who have normal levels of Omega 3 fatty acids in their system. However, a study that explored whether DHA plays a role in helping treat ADHD in conjunction with stimulant therapy, which is the standard therapy used in the treatment of this psychological disorder, showed that the fatty acid didn’t have any effects. As such, more research will need to be conducted to explore this topic further.
• Cognitive decline – According to some studies, lesser intake of Omega-3 fatty acids will put individuals at a higher risk of contracting age-related conditions, such as cognitive decline, dementia, and Alzheimer’s disease. This has led to some researchers to believe that Omega-3 plays a key role in protecting people from experiencing these cognitive problems.
• Inflammatory bowel disease (IBD) – Studies showed mix results as to whether Omega-3 fatty acids can help treat Crohn’s disease as well as ulcerative colitis, two forms of IBD. Some studies indicate that the fatty acids can help when used in conjunction with medication like sulfasalazine. More studies will need to be conducted to examine this further.
• Macular degeneration – A survey was conducted with 3,000 participants, all of whom were above 49 years old. The study showed that those who had more fish in their diet were less prone to get macular degeneration, an eye condition that can lead to blindness as a person ages, compared to those who didn’t eat as much fish. Another study with 350 people suffering from macular degeneration and 500 people without the condition as participants showed that those who had a diet rich in Omega-3 and Omega-6 fatty acids (including eating a lot of fish) were less susceptible to experiencing the eye condition.
• Dysmenorrhea – A study with 42 women as participants showed that taking fish oil supplements can greatly reduce menstrual pain compared to those who took a placebo drug.
• Colon cancer – Certain studies have been conducted that indicate that having an Omega-3 rich diet can also protect you from having colorectal cancer. For example, the Inuit are shown to be at less risk of colorectal cancer even if they have a fatty diet, simply because of the large quantity of fish they eat. Laboratory experiments and animal studies have also been conducted that indicate that Omega-3 can also lessen the symptoms of colon cancer, as well as slow down this disease, at the very least for those who are at the early stages of this illness. If you have cancer, make sure to consult with your doctor before you take any kind of supplement.
• Breast cancer – Women who follow a diet that has a lot of Omega-3 fatty acids are at less risk of developing breast cancer. However, more studies will need to be conducted to examine what role the fatty acid plays in preventing breast cancer.
• Prostate cancer – Population studies that have been conducted showed that men who follow a low-fat diet that’s rich in Omega-3, primarily those taken from fish and fish oil, can help prevent prostate cancer.

Reference: http://www.umm.edu/altmed/articles/omega-3-000316.htm

As of now, there is no recommended standard dose of Omega-3 fatty acids. The American Heart Association recommends taking 1 gram of EPA and DHA daily for those who are suffering from heart ailments. Those whose goal is to lower their triglyceride levels will need to take a higher amount than that, at about 2 to 4 grams every day. For those who have high blood pressure, a lot of scientists recommend taking 3 to 4 grams of EPA and DHA daily, however, you will need to consult and work with a doctor if youre planning to take Omega-3 in this high a dosage.

Risks – Pregnant women should observe a little caution when taking high levels of Omega-3, as are those who have bleeding problems, those who are taking blood thinning medications, and those who have high levels of LDL. Patients who have diabetes and schizophrenia may be suffering from a condition that prevents their body from converting ALA to EPA and DHA, forms of Omega-3 fatty acids that can actually be utilized by the body. Furthermore, those who have Type 2 Diabetes may increase fasting blood sugar levels when they take this supplement. As such, those who have this health condition are advised to consult with their physician with regard to taking Omega-3 supplements.

Interactions – Those who are taking the following drugs are not advised to take supplements with Omega-3 fatty acid without getting the approval of their doctor. However, Omega-3 fatty acids work very well in conjunction with a few medications below.

• Medications that thin blood – Omega-3 fatty acids increase the effect of medications that can thin the blood, such as aspirin, clopedigrel (Plavix), and warfaxin (Coumadin). While there may be some instances wherein taking Omega-3 fatty acids and aspirin may be beneficial to your health, these should only be taken in tandem under the supervision of a physician.
• Diabetes medications – Omega-3 fatty acids can increase the levels of fasting blood sugar. As such, you will need to consult with your doctor and observe caution when taking these supplements alongside medications designed to lower blood sugar, like insulin, glipizide (Glucotrol or Glucotrol XL), glucophage (Metformin), and glyburide (Diabeta or Micronase). If need be, your doctor may increase the dosage of the medication that you’re taking.
• Cyclosporine – Cyclosporine (Sandimmune) is a drug prescribed to people who have gone through an organ transplant operation. Taking Omega-3 supplements alongside cyclosporine therapy can lower the toxic side effects of this medication, including high blood pressure as well as kidney damage.
• Etrinate and topical steroids – Taking Omega-3 supplements, particularly EPA, while taking etretinate (Tegison) and other topical corticosteroids can help in the treatment of psoriasis.
• Medications that lower cholesterol – Increasing the amount of Omega-3-rich food that you eat while reducing the Omega-6 and Omega-3 ratio can help make statins, medications that lower cholesterol, work more efficiently. Dietary changes will need to be made in order to achieve this goal.
• Nonsteroidal anti-inflammatory drugs (NSAIDs) – An animal study that was conducted showed that Omega-3 fatty acids can reduce the possibility of developing ulcers when taking NSAIDs. Examples of NSAIDs are ibuprofen (Advil or Motrin) and naproxen (Naprosyn or Aleve). More studies will need to be conducted regarding the universality of these effects of Omega-3 fatty acids.