Skin is the organ that not only protects against microbes, pollution, and physical assaults, it is further important for sensory perception and in maintaining the body’s water content and temperature. It consists of several layers. The epidermis is towards the outside, with the top cell layer called the stratum corneum, which mainly consists of dead cells and oils. The body sheds the dead cells with a rate of up to 40,000 cells per hour. This can amount to as much as 3.6kg of dead skin cells in a year. Under the epidermis lies the dermis as an inside layer including sweat glands, hair follicles, and nerve endings needed to feel temperature, pressure, and pain.
The stratum corneum is important in preventing water loss to keep the underlying living cells moisturized. If its barrier function is disturbed, the skin can become dry and flakey. Hot water, soaps, medication, low humidity, and medical conditions can all lead to dry, irritated skin. For example, eczema is characterized by dry, red skin patches that can be very itchy, which might be due to an overactive immune system, but the exact causes are unknown. Also in the case of psoriasis, it is unknown why the immune system is not working properly, which leads to the formation of excess skin cells that build up in scales and red, itchy patches.
Healthy skin permits water loss only to a limited amount. Damaged skin, such as in atopic eczema, is characterized by increased water loss. Krill oil was shown to alleviate water loss and dry skin in a 12-week clinical study in healthy persons.
Both omega-3 fatty acids and phospholipids are important for skin health. Deficiency leads to scaling and dryness of the skin and enhanced transepidermal water loss (TEWL). TEWL describes the water loss over the surface of the skin that happens by passive diffusion. The outer layer of dead cells makes the skin flexible and elastic when it contains enough water. However, when the TEWL is high and hydration low, it becomes hard and rough. Hence, skin function is negatively affected, which can lead to discomfort or even infection.
In general, the skin holds about 30% of the body’s water and the dead cells of the stratum corneum and the lipids ‘waterproof’ the human body. Water loss and hydration of the stratum corneum is linked to its lipid content, the generation of new lipids in the skin, and ultimately the level of damage to the skin barrier function. A good balance between the skin’s water content and the amount of water passing influences skin elasticity, smoothness, and roughness and is crucial in maintaining healthy skin.
The skin has several functions, but one of the most critical ones is to maintain the body’s water levels and to limit water loss into the surroundings. Water makes up 75 (infants) to 55% (elderly) of the body’s weight and is vital for biological processes and life. A way to measure water loss is to assess transepidermal water loss (TEWL).
In contrast to e.g. saturated fatty acids and cholesterol, EPA and DHA cannot be made in the skin and must be obtained from outside sources. The skin lacks the enzymes needed to convert short-chain omega-3 fatty acids into the longer chain EPA and DHA. Omega-3 fatty acids levels in human skin are rather low with under 2% of total skin fatty acids. However, significant increases can be achieved by supplementation and 3 months of 4 grams daily EPA increased skin EPA 8 times.
Krill oil is an attractive dietary supplement that might help in the maintenance of skin health and treatment of skin disorders by both its omega-3 and phospholipid components (see above.)
To explore the effects of krill oil on skin health, 31 volunteers (middle-aged men and women with normal skin) were included in an open label, two-armed clinical trial (unpublished results). The subjects were randomized to take 3 grams daily krill oil for 13 weeks. All skin measurements were done on the upper forearm and showed that krill oil intake resulted in a significant increase in skin hydration and elasticity, as well as in a significant reduction in TEWL.
In addition, a significant correlation for the change in hydration and the changes both for elasticity and TEWL were found. Meaning that the volunteers that had a high change in skin hydration also experienced a high change for both elasticity and TEWL. By using a digital camera, the amount of wrinkles (as a measure for roughness) and width and size of wrinkles (as a measure for smoothness) were addressed at the start and end of the trial. For both parameters, i.e. roughness and smoothness, there was a significant beneficial change observed after krill oil supplementation.
By increasing the amount of omega-3 fatty acids in the body, krill oil has the ability to not only influence skin hydration and elasticity, but also the amount and size of wrinkles. The measure of how much omega-3 accumulates in the body, given as the Omega-3 index, was increased significantly in the study and correlated with the above-mentioned parameters. These results indicate that the increases in Omega-3 index by krill oil supplementation directly relate to the positive changes in skin parameters observed among study subjects.
Learn more about krill oil at www.medikrill.org
References:
Lena Burri Ph.D, L. Krill Oil Concentrate. Oslo, Norway: [s.n.], pp.18-21.