Body health and function

Omega-3 fatty acids provide a range of heart and cardiovascular health benefits, including:

• reduced cholesterol and triglyceride (a type of lipid similar to cholesterol) levels
• improved blood flow and circulation, and lower blood pressure
• improved vascular health and function, and decreased risk of arrhythmias.

Together, these benefits reduce the risk of cardiovascular events such as sudden cardiac death, non-fatal heart attacks and non-fatal strokes.

Heart disease

Studies suggest that omega-3 fatty acids can help to reduce the risk of cardiovascular diseases. These are rarely found in societies with a high intake of polyunsaturated fatty acids and are almost unknown among Eskimos and other arctic people.

Countries with traditionally higher fish consumption, such as Japan, also have a significantly lower rate of heart disease cases compared to those with low consumption, for example Germany.

In Japan, 32 people out of every 100,000 die from ischaemic heart disease (IHD). In Germany, this figure increases to 124, making it the number one cause of death in the country.

In 2004, the US Food and Drug Administration (FDA) gave 'qualified health claim' status to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with respect to their effect on reducing the risk of coronary heart disease.

Cholesterol

The human body needs cholesterol to function healthily; it's made by the body and obtained from foods. There are two types:

• high-density lipoprotein (HDL) or 'good' cholesterol
• low-density lipoprotein (LDL) or 'bad' cholesterol.

High levels of LDL cholesterol, which are often due to an unhealthy lifestyle ans a poor diet in saturated fat, increase risk of heart desease, heart attacks and strokes.

However, the long-chain omega-3 fatty acids DHA and EPA have been found to:

• lower and regulate LDL cholesterol and triglyceride levels
• increase HDL cholesterol
• reduce the risk of blood clots leading to heart attacks and strokes.

Blood pressure

The human body needs both omega-3 and omega-6 fatty acids, but it's important to maintain balance. If omega-6 fatty acids levels are high in relation to omega-3 levels, there may be too much arachidonic acid   (a derivate and 'bad' eicosanoid).

This contributes to increased inflammation and atherosclerosis (where artery walls thicken due to a build-up of fatty materias, such as cholesterol, which harden and may block the arteries).

However, omega-3 fatty acids (and their derivatives, the 'good' eicosanoids) can help to lower blood pressure by dilating the blood vessels. This in turn also lowers the risk of blood clots.

Long-chain omega-3 fatty acids are needed for:

• brain cells, neurons and neurotransmitters to work properly
• membrane health, enzyme regulation and nerve function.

They make up a large proportion of the brain and docosahexaenoic acid (DHA) makes up half of the fat in brain cell membranes. It's concentrated in important areas such as the cerebral cortex, synapses and mitochondria.

Omega-3 essential fatty acids are known to:

• improve learning ability, cognitive function, memory and thought
• increase mental alertness, focus, concentration and creativity
• reduce stress.

Brain diseases

People who eat a diet rich in omega-3 fatty acids have younger, healthier brains. It is likely that both eicosapentaenoic acid (EPA) and DHA have positive effects against a number of brain diseases.

Omega 3 may help to prevent or slow down serious mental conditions such as Alzheimer's, dementia and Parkinson's. Individuals with these diseases have been shown to have much lower levels of DHA and EPA in the brain plasma.

Psychiatric and mental disorders

Omega-3 fatty acids benefit brain function and mental health.

Omega-3 essential fatty acids benefit brain function and mental health. They have been found to benefit various disorders, such as depression, bipolar disorder, personality disorder and schizophrenia.

Depression

Studies have shown that consuming a diet high in long-chain omega-3 fatty acids can help to prevent and alleviate depression. In fact, nations with high fish consumption have a low incidence of depression.

High levels of omega-6 fatty acids and low levels of omega-3 fatty acids – resulting in a poor balance – have been linked to depression. Some scientists believe an increase in omega-6 consumption has led to an increase in this and other mental problems in modern society.

Depressed individuals often have low levels of 'feel-good' chemical serotonin (a neurotransmitter and mood regulator), which is itself linked to low levels of omega-3.

Schizophrenia

A deficiency of polyunsaturated fatty acids in the brain may also be linked to schizophrenia. Sufferers have low levels of both omega-3 and omega-6 in their cell membranes.

In addition, when compared to healthy brains, their red blood cells contain half as much DHA. However, some studies have shown that EPA may be better than DHA in terms of positive effects on schizophrenic brains.

Learning and behaviour

An imbalance between omega-3 and omega-6 fatty acids may also affect learning and behaviour.

While further research is needed, individuals with dyslexia and attention deficit hyperactivity disorder (ADHD) may require more long-chain omega-3 fatty acids for their brains to work and develop normally.

A 2005 study from Oxford showed that both fatty acid groups can help people with developmental co-ordination disorder (DCD), often linked to learning and behaviour difficulties.

Arthritis

Long-chain omega-3 fatty acids act as an anti-inflammatory and may be effective against rheumatoid arthritis; they have been linked with significantly reducing arthritic symptoms.

These fatty acids may also enable arthritic patients to reduce their consumption of non-steroidal anti-inflammatory medicines. Other studies have shown that regular fish consumption correlates with a lower incidence of the disease.

Intestinal disorders

As well as rheumatoid arthritis, long-chain omega-3 fatty acids may benefit sufferers of Crohn's disease and other inflammatory intestinal disorders.

Good nutrition is important for maintaining bone, cartilage and joint health. Related diseases and disorders – such as abnormal bone formations and joint inflammation – are increasingly common in modern society.

Omega-3 fatty acids have been linked to decreasing the risk of illness, relieving symptoms and reducing discomfort. They provide benefits in terms of, for example, bone metabolism, inflammatory reactions and cartilage degradation.

Healthy joints

Omega-3 fatty acids stay liquid even at low temperatures. It's this quality that not only allows cold-water oily fish to survive, but also benefits human joints, tackling inflammatory illnesses such as arthritis.

An omega-3 rich diet has also been linked with:

• reducing joint pain intensity, plus joint stiffness and tenderness
• alleviating the pain of inflammatory joint disease
• delaying the degradation of joint cartilage
• regulating inflammatory reactions in joints

These fatty acids may also enable arthritic patients to reduce their consumption of non-steroidal anti-inflammatory drugs (NSAIDs). In addition, omega-3 supplements have almost no unwanted side effects, as either a complementary or an alternative form of medicine.

Strong bones

Omega-3 fatty acids have been linked to maintaining and improving bone health at all ages, including:

• in childhood and adolescence – skeletal growth and bone formation
• early adulthood – peak bone mass is reached
• throughout adult life  – the bone remodelling cycle (when bone is broken down and formed).

For example, studies have shown that individuals who consumed omega-3 diets rich in:

• fish-based eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) had decreased bone loss
• plant-based alpha-linolenic acid (ALA) had decreased levels of blood chemicals that indicate bone loss, while those that indicate bone formation stayed the same.

Osteoporosis

A major symptom of osteoporosis is reduced bone density, leading to increased risk of fractures, pain and immobility. Sufferers include post-menopausal women and those with specific hereditary genetic factors.

Researchers have found that the more omega-3 fatty acids (particularly DHA) in an individual's blood, the greater their bone mineral density. Animal studies have also indicated that DHA helps calcium absorption.

By considering the risk factors and modifying diet and lifestyle appropriately in childhood and as a young adult, the risk of osteoporosis in later life can be reduced.

Cancer

Some studies show that populations that eat lots of fish have lower incidences of many types of cancer, including breast cancer.

In studies by Dauchy and Sauer, cancer tumours in rats grew faster when given a diet high in linoleic acid (an omega-6 fatty acid), than when given a diet high in saturated fat. However, omega-3 fatty acids slowed down the tumour growth.

In terms of skin cancer, eicosapentaenoic acid (EPA) protects against DNA damage caused by ultra-violet (UV) radiation. Given a long-term dietary change, the number of skin cancer occurrences could potentially be reduced.

Skin conditions

In a study with patients with chronic stable psoriasis (an inflammatory dermatosis), an EPA-rich supplement was proven to reduce itching, erythema and scaling. The area of affected skin also decreased in many cases.

In addition, EPA has been proven to have an anti-inflammatory effect in atopic dermatitis.