One of the biggest misconceptions is that all fats are bad for health.
The truth is fat is one of the major nutrients that your body needs to function optimally. For example, fat helps the body to digest food and nutrients, supports organs in position, acts as a source of energy, protects the body from mechanical pressure, insulate the body, and most importantly, keep human survived during food limitations.1 Hence, incorporating healthy dietary fats is crucial for maintaining overall well-being.
Fatty acids act as the building blocks of the fat in our bodies. The body uses essential fatty acids for cellular processes. However, our human body is unable to produce them by itself. Thus, they must be taken in through diet or supplementation. Omega-3 fatty acids are one of the known essential fatty acids which link to numerous health benefits. Read on this article about the science-backed beneficial effects of the omega-3 fatty acids – docosahexaenoic acid (DHA).
What is DHA?
Docosahexaenoic acid (DHA) is one of the major omega-3 fatty acids found concentrated in fish and marine oil, particularly the oil from cold-water fish, including salmon, tuna, mackerel and anchovies. It is also present in marine algae. In the human body, DHA is highly concentrated in the eyes and brain area. Thus, it is crucial for visual and brain function.
The Beneficial Effects of DHA for Human Health
DHA & Brain
About 90% of omega-3 fatty acids in the brain is DHA2, which makes DHA a critical nutrient for the growth and maturation of an infant’s brain. Sufficient maternal DHA store is crucial as DHA is delivered to the fetus and infant through placental transfer and mother’s milk. Research reviews supported that the supplementation of DHA during pregnancy increased infants’ birth weight and birth height3, as well as reduced the risk of preterm births.4 DHA involvement in the central nervous system has also played a part in improving learning and memory among school children.5 Ageing process has naturally declined the cognitive function among the elderly. Fortunately, DHA intake has shown to slow down the cognitive decline in healthy ageing populations.6 An earlier study reported that patients with dementia, Alzheimer’s disease and cognitive impairment have less DHA in plasma than healthy subjects. Regular intake of DHA can be more than a preventive measure for developing cognitive impairment in adults and elder populations. It has improved overall signs of dementia, mild cognitive impairment and Alzheimer’s disease.2
DHA & Eyes
Our retina contains the highest concentration of DHA as compared to other parts of the body tissues. It helps to regenerate rhodopsin, a sensory protein that is located in the retina of the eye and helps us to see under dim light.7 Deficiency of DHA is associated with visual function impairment.8 An early supplementation of DHA in infant formula will aid the development of the eyes of infants, as suggested by studies.9,10Besides, DHA can relieve dry eye syndrome by increasing tear secretion and suppressing the inflammation in ocular tissues.11,12 DHA intake is beneficial to diabetic patients as it prevents the progression of diabetic retinopathy, mainly due to its anti-inflammatory and antioxidant properties.13 Recent studies have shown that DHA supplements can lower the intraocular pressure of patients with glaucoma by reducing oxidative stress and inflammation.14,15 The finding has shed light on the potential effects of DHA for improving and preventing ocular hypertension and glaucoma.
DHA & Heart
The relation between the intake of omega-3 fatty acids, such as DHA and cardiovascular disease (CVD) was first discovered by a researcher in 1976.16 Since then, numerous studies have documented the potential effects of omega-3 fatty acids in preventing heart-health issues. One of the studies found that supplementing fish oil rich in DHA and EPA for 12 weeks has reduced the subjects’ blood triglycerides and increased the concentration of HDL (high-density lipoproteins, also known as the “good cholesterol”).17 Most of the time, studies are demonstrating the beneficial effects of the combination of DHA and EPA. In one study, DHA intake has reduced blood pressure and heart rate of overweight subjects. However, the same results have not appeared in EPA intake.18 The finding suggested the importance of DHA in maintaining healthy blood pressure levels. DHA has played a crucial role in regulating vascular health and preventing endothelial dysfunction, which is associated with heart diseases such as atherosclerosis, hypertension and coronary artery disease and stroke.19
Other Potential Effects of DHA
Prevents loss of muscle mass and strength
Loss of skeletal muscle mass and strength is prevalent in the ageing population. Lack of exercise or physical disability, lack of appetite and reduced food intake due to the use of medications can lead to malnutrition and sarcopenia (gradual loss of muscle mass) in older people. A study has shown that regular intake of omega-3 fatty acids can slow down the loss of muscle mass and function in older adults.20
Improves skin conditions
Skin condition such as atopic dermatitis, or commonly known as, eczema, is caused by an overactive immune system that triggers inflammation. A pilot study determining the efficacy of DHA in patients with atopic dermatitis found that supplementation of DHA has successfully lowered the inflammation level and reduce the severity of patients’ skin condition.21 Besides, the anti-inflammation effect of DHA may potentially offer protection against sunburn, photo-ageing and skin cancer.22
Alleviates arthritis symptoms
The omega-3 fatty acids may help to improve rheumatoid arthritis (RA) symptoms due to their anti-inflammatory properties. A study demonstrating the efficacy of omega-3 fatty acids has concluded that daily consumption of DHA have reduced tender and swollen joints, as well as reduced joint pain in RA patients.23