Depression is one of the most common mental disorders in the world.
Anxiety, also a common disorder, is characterized by constant worry and nervousness ( 3 ).
There are three types of omega-3 fatty acids: ALA, EPA and DHA. Of the three, EPA appears to be the best for fighting depression ( 9 ).
One study even found EPA to be as effective for depression as a common antidepressant ( 10 ).
DHA, a type of omega-3, is a major structural component of the retina of the eye ( 11 ).
Omega-3s are crucial for brain growth and development in infants.
Therefore, it’s no surprise that infants fed formula fortified with DHA had better eyesight than infants fed formula without ( 17 ).
- higher intellect
- Better communication and social skills
- Fewer behavior problems
- Reduced risk of developmental delay
- Reduced risk of ADHD, autism and cerebral palsy
Heart attacks and strokes are the leading causes of death worldwide ( 21 ).
Since then, omega-3 fatty acids have been linked to many heart-healthy benefits ( 24 ).
These advantages relate to:
Omega-3s can cause a significant reduction in triglycerides, usually around 15–30%
( 25 , 26 , 27 ).
- Blood pressure:
Omega-3s may lower blood pressure in people with high blood pressure ( 25 ,
- “Good” HDL cholesterol:
Omega-3s may increase “good” HDL cholesterol ( 29 ,
- Blood clots: Omega-3s can prevent
blood platelets from clumping together. This helps prevent the formation of
harmful blood clots ( 32 , 33 ).
- Plaque: By keeping your arteries
smooth and free of damage, omega-3s help prevent plaque that can narrow
and harden your arteries ( 34 , 35 ).
Omega-3s reduce the production of certain substances released during
your body’s inflammatory response ( 36 , 37 ,
Despite these beneficial effects on heart disease risk factors, there is no convincing evidence that omega-3 supplements can prevent heart attacks or strokes. Many studies find no benefit ( 41 , 42 ).
Attention deficit hyperactivity disorder (ADHD) is a behavioral disorder characterized by inattention, hyperactivity and impulsivity ( 43 ).
Additionally, numerous studies observe that omega-3 supplements can reduce ADHD symptoms.
Recently, researchers observed that fish oil supplements were one of the most promising treatments for ADHD ( 50 ).
6. Omega-3s May Reduce Symptoms of Metabolic Syndrome
Metabolic syndrome is a collection of conditions.
This includes central obesity — also known as belly fat — as well as high blood pressure, insulin resistance, high triglycerides, and low levels of “good” HDL cholesterol.
It is a major public health problem because it increases the risk of many other diseases, including heart disease and diabetes ( 51 ).
7. Omega-3s Can Fight Inflammation
Inflammation is a natural response to infections and damage in your body. It is therefore vital for your health.
However, the inflammation sometimes persists for a long time, even without infection or injury. This is called chronic or long-term inflammation.
In autoimmune diseases, your immune system mistakes healthy cells for foreign cells and begins to attack them.
Type 1 diabetes is a prime example, in which your immune system attacks the insulin-producing cells in your pancreas.
Omega-3s can fight some of these diseases and may be particularly important early in life.
Studies show that getting enough omega-3s in your first year of life is linked to a reduced risk of many autoimmune diseases, including type 1 diabetes, autoimmune diabetes, and multiple sclerosis. ( 62 , 63 , 64 ).
Low levels of omega-3s have been reported in people with psychiatric disorders ( 69 ).
Supplementing with omega-3 fatty acids may also decrease violent behavior ( 72 ).
The decline of brain function is one of the inevitable consequences of aging.
A review of controlled studies suggests that omega-3 supplements may be beneficial early in the disease, when AD symptoms are very mild ( 76 ).
Keep in mind that more research is needed on omega-3s and brain health.