Take CARE AND PROTECT YOUR SKIN IN SUMMER (part 3)
How is pigmented skin?
Our skin pigmentation or skin color is determined by melanin, a pigment produced by melanocytes (coarse dendritic cells found in the basal layer of the epidermis), synthesized specifically in the interior of these, in a few specific organelles called melanosomes.
Melanosomes migrate later to the surface of the skin, thanks to the mediation of the keratinocyte cells (more superficial).
Our number of melanocytes is set at birth, and their reproduction is difficult. After the birth will begin to function and to produce melanin slowly.
Melanocytes are distributed throughout the body except on the palms of the hands and soles of the feet, and mucous membranes.
The number of melanocytes is not proportional to the color of the skin, but the latter will depend on the function, form, and content of the melanosomes.
This means that the darker colors of skin do not depend on the amount of melanocytes that have, but the amount of melanosomes that contain and how they are transferred to keratinocytes in the superficial layers of the skin, with its melanin content.
According to the pigmentation of their skin, there are three races:
– Celtic: blondes or redheads with fair skin is not pigmented, as they have very few melanosomes. These melanosomes are you're destroying and losing the melanin progressively in the migration of keratinocytes to the surface. They are individuals, not bronceables and always burns.
– Caucasian: white people skin clear and matt. Have numerous melanosomes loaded with melanin. The more sun exposure, the more you can get a tan, for the possibilities of migration of melanosomes to the surface. There, the melanin is released, and is formed in a greater or lesser extent depending on the stimulation of melanocyte by the solar radiation.
– Negroid: black people to a greater or lesser extent. Their melanosomes are very numerous and arrive intact to the surface of the skin, releasing its melanin and coloring the skin very intense.
Phototypes of skin
Each individual, depending on their breed, it synthesizes one or another type of melanin, and in different proportions, which will determine your skin type of skin.
The eumelanina is a brown pigment and pheomelanin is a red pigment.
The celts mainly synthesized pheomelanin, which is a pigment, non-protective and potentially carcinogenic, therefore, these people have difficulty getting a tan.
Caucasians are the two types of pigment, whose proportions will influence the tone of the skin.
Blacks only synthesize eumelanina; and asians (skins-called “yellow”) are included in the group of caucasians, although their melanosomes are shaped and maturation distinct and eumelanina comes to the surface permanently, but in small amount, increasing his production and sun exposure.
So, the world population is distributed in 6 phototypes:
– Phototype I: tan (celtic)
– II: tan, light (white)
– III: tan medium (caucasian)
– IV: tan to dark (white)
– V: skin naturally brunette (white brown)
– VI: black skin (negroid)
There are problems in pigmentation:
– by default (hypo pigmented): as vitiligo (areas of the skin are absent melanin which appear white), gray hair, phenylketonuria (disease of deficit of transfer of melanosome and his melanin in children very white and blonde hair pale) and albinism (absence of synthesis of melanin, no pigmentation in skin, hair, iris, revealing the hair and the skin white, and the iris is red, colored by the blood capillaries).
– excess (hyper pigmentation): as the lentigo senile (spots in the skin by sun exposure in skin aging or mature, ephelids or freckles, melasma, or chloasma (mask of pregnancy”), the dermatitis “in suspension” (after the application of perfume with bergamot) or hyperpigmentation scarring (after burns in small areas).
Irradiation and the effects of sun on the skin
Sunlight is composed of various types of radiation, called radiation, actinic.
Not all reach the surface of the earth, and that we receive that are distributed depending on its wavelength and its effects on the human organism, and more specifically on our skin.
Types of solar radiation ultraviolet that affect us:
UV – C: they are retained in the upper layers of the atmosphere, coming to the ground only a 2%, hence the importance of maintaining protected the ozone layer to avoid damage caused by this radiation. They are produced artificially by the lamps germicidal.
– UV A and B: represent 12% of the radiation actinic incidents and an increase of 15% for each 1000 m of altitude. Are the radiation responsible for tanning and sunburn.
Other radiation is the radiation of visible and ir (infrared).
The effects of the sun on your skin will depend on the amount of energy absorbed and the depth of the penetration, which is proportional to the wavelength.
Radiation is sorted increasingly in terms of their amount of energy in: UV-B, UV-A, visible and IR.
In terms of penetration (according to wavelength), the GO penetrate to the hypodermis, the UV up to half of the dermis and UV-B to the dermo epidemic union.
– Oxidation-reduction reactions, where they form free radicals. Cell membranes are denatured and release mediators of inflammation (histamine, serotonin, prostaglandins), it causes vasodilation of the capillaries causing erythema (redness) and edema (swelling). These reactions are caused mainly by UV-B.
– Reactions on proteins and nucleic acids that result in changes in the molecules of collagen and elastin. Modifies the connective tissue, producing the appearance of signs of premature aging and skin aging. These reactions are caused by UV-A.
Other changes that occur are changes in the DNA, that the body itself can be repaired by certain mechanisms. When this does not occur may appear skin cancers.
In addition to the UV B radiation modifies the Langerhans cells producing phenomena of immunosuppression or immunodeficiency, (interesting in the treatment of psoriasis, which is an overreaction of the immune system).
There are a number of different conditions of solar or aggravated by exposure to sunlight that occur only in some individuals (effects not collective) in consequence of the phenomena of photosensitization: diseases such as cutaneous porphyria, pellagra, the lucitis urticaria, solar, herpes, and rosacea (which are compounded by the sun), and dermatitis of unknown origin, phototoxic and photoallergic.
Except for these specific cases, which occur in some people, the rest of the conditions solar are common to all individuals, appearing more or less quickly according to the sensitivity of each person (collective effects).
The effects of the sun common are: erythema solar (redness during and a few hours after the sun exposure), pigmentation problems (before mentioned), and the degeneration of the dermis and the epidermis (skin aging).
Other collective effects, the more rare but in large increases in recent years are:
– the skin cancerdue to the UV-A and UV-B, the more easily developable in individuals with skin type is clear and in the light-exposed areas. Its frequency is related to the radiation received in the previous 10 years (cumulative damage of the sun). Carcinomas and melanomas.
– the xeroderma pigmentosum, a condition that is very serious in subjects lacking a system of DNA repair. Appear tumors are very numerous, and early, in children who do not usually reached adulthood. Are tumors that should be removed immediately as they appear.
How do you protect our skin from solar radiation?
Naturally, our skin has mechanisms to protect itself from sun damage. These mechanisms are:
– pigmentation (when we bronceamos)
– thickening of the horny layer of the epidermis
– the production of acid, urocanic acid, which appears in the sweat
Of these, the most interesting to be able to help protect the skin of an active and voluntary are the first two.
There are two types: the direct (by UV radiation), which appears in 6 hours, it is very fleeting and does not occur in all individuals; and the indirect, or delayed, due to UV-B, which appears to 48 hours and follows the erythema. This last is due to the increase of melanin synthesis and the proliferation of melanosomes by excitation of the melanocyte.
According to our skin type skin, we'll most “brown” or tan the more UV B radiation we receive from the sun as a protective response against burns and other injuries before mentioned, or we will stay white without the skin pigmente and will get burned.
Whether our phototype allows the natural pigmentation (tanning) as if you do not, we must protect the skin from sun damage by protective artificial: screens, filters and capture of free radicals.
It is important to remember that the bronzing products artificial, especially for topical application, pigmentan or color the skin, but does not protect from sun damage, so that, if we use them, we must also use creams, lotions, sprays, etc, with a protective effect.
Thickening of the horny layer
Radiation UV-B produced an increase in the number and thickness of the layers of keratinocytes in the epidermis alive, it increases its keratinization and thickens your horny layer. Cells displayed “sunburn” (burnt by the sun) into the deep layers of the epidermis exposed to solar irradiation.
In the first three days after exposure, the epidermis becomes queratósica, slowly disappearing the horny layer thickened and returning to normal in 10 to 14 days.
The UV radiation TO repeatedly produce a thickening of the horny layer without appearance of “sunburn cells”.
On the skins which have undergone a sun burn (the skin has not been adequately protected, naturally or artificially), depending on the degree of the burn, it appears only a rash a few days, a few small vesicles or flictenas with liquid (is a serous layer of fluid between the damaged skin and the deeper layers of epidermis and dermis), the so-called “fever blisters”, and the separation of the skin is more superficial, being able to get up and peel off when dry, or withdraw, until wounds burn more serious that require measures of disinfection and cures, when you have a significant loss of dermal tissue.
How do we help to protect our skin from damage by solar radiation?
As we have said, we can and should use products to protect our skin from solar radiation, both internal as well as external.
At the external level, we will turn to specific products pharmaceutical and non-pharmaceutical chemist's, topical, in the form of sticks, oils, emulsions, gels, creams, sprays and aerosols, the objective of which is to act as screens (reflect the entirety of the radiation), filters (absorb part of the radiation) or captors of free radicals (photoprotective active radiation that is not absorbed), which are formulated with a filter.
Today, we can find in the market various products with different formulation, and trademarks, with less chemical ingredients or artificial toxic or unhealthy (sunscreens organic or more natural and friendly to our skin and to the environment).
The products of sun protection, topical have an index of sun protection and sun protection factor (SPF) or sun protection factor (SPF).
This index refers to the effect of sunscreen against UV-B, although in recent years methods were used to determine the index of protection against UV-A, by including them in the formulations of the products.
The rate FPS is the multiplying factor of the time of self-protection the skin's natural, that is to say, will determine the time that we can expose ourselves to the sun without that appears erythema, on the basis of our features, arising from, out of our skin type.
For example, if we have a phototype III (tan medium in caucasians), we can expose ourselves to the sun, at noon, at the level of the sea, in the summer, without showing erythema, during 20 minutes of self-protection natural.
If we use a product of SPF 6, we will be 120 minutes in the sun, in the same conditions, before it appears erythema.
Internally, we have already talked about in previous posts of those nutrients that can help prevent cell oxidation, preventing the emergence of free radicals), to maintain the good health of collagen and other connective tissue cells or promote cell regeneration, healing and decrease inflammation.
However let's remember that will be beneficial foods and supplements rich in vitamin A (to promote keratinization and cell regeneration of the epidermis and stimulate the synthesis of collagen), some B-group vitamins (to activate the pigmentation, as the B5, or promote cellular respiration and regeneration), vitamin E (to protect proteins, collagen, elastin, and lipids of the cell, acting as antioxidant and anti-free radical), amino acids (which are involved in the nutrition and cell reproduction) and carotenoids, as the beta-carotene (with wound healing properties, anti-inflammatory and antirradical).
How to prevent or reduce sun spots for hyperpigmentation?
It is common the appearance of spots, hyper-pigmentation, especially after a certain age, and higher in women, in areas such as the face, hands, or forearms.
For this problem there are also cosmetic products specific to lighten the skin (depigmentation), such as kojic acid, agents of peeling as retinoic acid or glycolic acid, which speed up the removal of the pigmented cells.
Other products that are taken orally, or applied topically prior to exposure to the sun, inhibit, or limit the synthesis or transport of melanin, preventing pigmentation.
Naturally, although of limited effectiveness, antioxidants such as vitamin C reduce the melanin already oxidized melanin more clear, and in its form of ascorbyl phosphate magnesium (also the mineral magnesium) is a substance that is very well tolerated by the skin, unlike other substances, more aggressive, such as those mentioned above.
The foods and supplements rich in vitamin C of natural origin can help to visibly reduce the coloration of the spots already in place and prevent the new onset.
To prevent sunburn, to promote the natural tan and stimulate the hydration, the skin regeneration and to reduce the effects of oxidative and inflammatory os we want to propose you a tasty recipe, rich in nutrients and light and cool for these summer days.
Do you want to come to try it?
Smoothie Tan Healthy Ecolife
– 1 cup of strawberries, blueberries or blackberries
– 1 large carrot
– 1 ripe tomato medium
– 1/2 red bell pepper
– Juice of one orange
– 1 tablespoon of Acai Powder Ecolife Food
– 1 tablespoon of Spirulina Powder Ecolife Food
– Brown sugar cane, honey, or stevia to taste
– Purified water to taste
Wash and peel the fruit and remove the seeds and rabitos. We incorporate all the ingredients to a blender or grinder and add water to taste and sweetener also to taste. Serve at room temperature or cold. We can add to the grinder along with the ingredients and a few ice cubes and serve it as a sorbet.
That's delicious and refreshing!
We hope to see you in the next post.
Sara Gómez Marquina
Specialist in Alternative Therapies, Naturopathy and Nutrition. Physical therapist
Collaborator of Ecolife Food and Club Manager AV Natural Cantabria