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Cyber Beautybox
Questions & Answers
On
Effects Of UV Rays On Skin
Question
I read an article several years ago regarding sun tanning. It stated that
the sun would continue to burn your skin for a while after you are through
tanning, and that you needed to take a shower to wash "it off". Several of
my friends think I am crazy, and I cannot find the article to prove it.
One wants to bet me that who ever is wrong has to bungie jump..I need help.
ASAP, Is it true what I read? Thank you for your help.
(submitted by alias: CJ)
Answer
Hi CJ,
when you suntan under natural sunlight(i.e. not salon tanning beds which
emits only artificial UV-A rays) you are receiving both UV-A and B rays.
UV-A rays radiate deep into the dermis layer, but has lower energy than
the B rays. Both the epidermal and the dermal layers contain melanin(black)
cells which give us our skin tone, depending on their concentration level.
UV rays cause a chemical reaction to the melanin cells, which then lead to
rapid melanin cell multiplication. Because A rays penetrate both layers of
melanin cells the multiplication of melanin cells in two layers produces a
dark tone(i.e. the tan look) very quickly.
The B rays, on the other hand, do not penetrate as deep as the A rays.
B rays penetrate only up to the epidernal layer, and therefore will cause
only the epidermal layer's melanin cells to multiply. So, the skin won't
tan as fast as if exposed to the A rays. However, the B rays have much
higher energy than the A rays, and because of this, it burns. The B rays
energy will not deplete as fast as the A rays, and will accumulate on the
skin. Over time, the accumulated energy causes the melanin cells to
multiply gradually. This slow process of multiplying the melanin cells is
termed delayed pigmentation, appearing on the skin as uneven brown patches
usually.
For people who love tanning, usually they do not want to get burned.
So they apply a cream that contains anti-UVB agents to block off the B
rays, and to allow only the A rays to pass through in order to get a
quick tan.
If such a cream is applied, then it is less likely to get any burn during
or after a tan, provided of course the person doesn't over-expose to the
sun by exceeding the limit the cream can protect.
However, if no cream is applied, then the person is receiving both the A+B
rays. In such a case, the high B rays energy will not deplete immediately
but will retain and accumulate. So, it is true that it will burn the skin
for some time(even up to a few days after say, a 3 to 5 hours exposure
under the hot afternoon sun).
Taking a shower, however, will not wash away the burn, but it does help a
little by cooling off the temperature left by the B rays. Soaking in a
cold bath tub of water will cool off the body temperature better, but it
will not deplete all the accumulated B rays energy.
Regards: Pierre
Question
Hello. I would like to know what treatments/products you would suggest
using for my skin problems. I have a pigmentation problem on the right
side of my face that has worsened progressively over the past five years.
It started as a small spot on my cheek and has increased to most of the
right side and has moved to my forehead. I have had numerous glycolic
peels, used Renova, RetinA and other bleaching cream. I think all of
these things have just worsened my skin condition and made it extremely
sensitive to any sunlight and resulted in more acne type problems.
I do take birth control pills, but the pigmentation problem started and
progressed long before I started taking them. Your recommendations would
be greatly appreciated. Thank you. Laura
(submitted by alias: laura)
Answer
Hi Laura,
with your current condition, the first thing you must avoid is exposure to
the sun. Use a good sunscreen with SPF 8 to 15 is sufficient. Do not use
one that's higher. Sunscreens with higher SPF can cause lots of other
complications to the skin. To know more about SPF please visit
http://www.pierrechenxu.com/spf_us.html
Artificial peels often caused more harm than good. After a fresh peel,
the skin temporarily appears soft and fair, but actually, it is due to
the dissappearance of some of the epidermal sub-layers which have been
peeled off. With the loss of some sub-layers, naturally the skin has a
much thinner epidermal skin, thus less protective capability against the
sun's harmful UV rays.
I advice that you stop receiving such treatment altogether.
Birth control pills can also cause a hormonal imbalance in your body over
time, and leading to some melanin cells to over-multiply themselves.
Although your pigmentation problem started and progressed long before you
started taking them, it does not necessarily mean that it is not one of
the current additional causes to your pigmentation problem. If, after
having avoided the sun and having used a good sunscreen for some time,
there's still no improvement, then the primary cause of your pigmentation
now is due to the pills. Of course your skin peels and past exposure to
the sun are most likely the early causes to your pigmentation problem,
but your pills could have become a later problem contribution source.
Bleaching creams can only work, provided the source of the problem can be
controlled.
Nevertheless, all other daily/nightly skincare products used also play a
role to some extent in your resulting skin condition.
I urge you to try our samples.
For your convenience I have pasted a copy of our text version Sampleset
Request Form below here for your completion.
(Note: Actual form contents are removed from here to save space)
Best Regards: Pierre
Question
I have used a tanning bed 3 times for 10 minutes each time;
I am beginning to see white spots on my legs; Is this being
caused by the tanning bed and is there anything I can do to
get rid of them.
Thanks
(submitted by alias: waterbaby)
Answer
Hi Waterbaby,
the answer is yes and no. The white spots are melanin cells that have been
depigmented, and cannot multiply themselves when stimulated by UV rays.
This is of course not natural, but it happens to most people. All other
normal melanin cells when exposed to the UV rays will automatically
multiply themselves, thus becoming more in numbers and more concentrated,
and appearing darker in shade(i.e. Tan) so as to shield and protect the
skin better against UV penetration. This is a natural physiological
phenoma(a great creation of our good God) to protect our skin from further
damage by the harmful effects of UV rays.
So when cells that are normal and when exposed to UV rays became darker,
the remaining abnormal cells that do not multiply and remain the same
obviously appear as if they are white spots in the darker cells
surrounding area. So these white spots were not caused by the UV rays to
become white, but were caused by the surrounding cells which became
darker through UV exposure, and highlighting them as if they are white
spots.
I don't encourage this kind of treatment. Tanning beds emit artificial
UV-A rays which possess deep penetration ability, upto the dermis layer,
causing both layers of melanin cells to multiply. Although UV-A rays
energy is lower than that of UV-Bs, we are all already exposed daily to
the sun's natural UV-A and B rays as well. So everyone of us have enough
absorbtion of UV-B rays every day. UV-B rays that accumulated on our skin
can be highly activated by additional UV-A rays to cause serious harmful
effects on skin, leading to skin cancer in the long run.
Stop this treatment for a while and let the tanned cells get back to
their normal concentration level, and the white spots will disappear
gradually.
Regards: Pierre
Question
I really appreciate that evrey time you answer my
question. You are the real expert of the skincare.
I think I will keep using the UV cream with jojoba oil.
I have another question (Sorry to bug you again) which
is " Is it better for the skin to take sun, properly,
once in a while?" I stop taking sun since this Summer
(before I was taking sun until I get suntun every year)
because I realize that I am getting more spots on my
arms.
sincerely,
Sachiko S.
(submitted by alias: Sachiko)
Answer
You are welcome, Sachiko, with your questions always.
I'm always glad to see that someone receives proper
help when needed.
The UV rays from the sun is very harmful, and is the
main cause to your spots. In Australia, the peoples'
love for sunbathing in the past has contributed to
the country's skin cancer rate as being the highest in
the world. Today, instead of seeing people around naked,
bareback, or in bikinis at the beach, more and more
people are aware of the danger now, and are wearing
large straw hats, and having more clothings on for
protection. By the way straw hats(or even umbrellas)
won't really help much. Lot's of UV rays are reflected
from walls, ground, and every surfaces onto a person's
skin.
Yes, a bit of sunlight is good for your skin. However,
even without having to go out directly under the sun
for a sunbath, you are already receiving and absorbing
lots of UV rays in the day. UV ray is just next to the
'visible rays' in the light spectrum of rays. Visible
rays are rays that when present allow us to see an
object - without visible rays will mean complete
darkness, and we can't see anything. So you can safely
assume that as long as there are visible rays around,
there are also UV rays present(since these two rays
are just next to one another). You can therefore go
further to assume that so long your eyes can still
see something(i.e. not complete darkness), there is
UV rays present.
So even when you are at home or in the office
(indoors), so long there is still good visibility,
you are already absorbing UV rays reflected from the
outside into your home/office.
So avoid sunbathing totally. There's no need for that.
You are already receiving adequate amount of UV rays
daily naturally.
Regards: Pierre
Question
I have a question. Isn't a suntan just a precursor to a sunburn?
In other words, wasn't every sunburn a suntan a few hours
earlier. What does suntan lotion do? My theory is that it does
nothing more than lengthen the amount of time before everything
happens. If you would get a tan in 40 minutes and a burn in 60
w/o lotion, then wouldn't putting on #2 just make it take 80
minutes to tan and 120 to burn? Please help me. If you have
a web page i could reference it would be great
thanks
cameron
(submitted by alias: Cameron)
Answer
Hi Cameron,
A suntan may usually appear as a precursor to a sunburn,
but not always, and not under all circumstances.
The sun's rays comprise a portion of spectrum classified by
scientists as Ultra-Violet(UV) rays. These are further
divided into UV-A, UV-B and UV-C. UV-C is mostly shielded
by the earth's ozone layer, leaving UV-A and UV-B to
penetrate our atmosphere. UV-A penetrates both our epidermis
and dermis skin layers. Since the basal layer(the last layer)
of the epidermis and the prickle-cell layer(the first layer)
of the dermis both contain melanin cells(melanocytes), these
two layers of cells are stimulated simultaneously by the UV-A
rays to produce more melanocytes - a natural chemical
reaction geniously created by our God Almighty - to prevent
the harmful effects of the UV rays against the underlying
cells. In other words, the hyper-production of more melanin
(melanin means black) cells is to provide a more opaque skin
layer(which otherwise would be more translucent) in order to
obstruct penetration of the UV rays. It is for this reason
(that is, two layers of skin containing melanin cells being
stimulated to multiply melanocytes simultaneously), that UV-A
causes sun-tanning. Tanning-beds in beauty salons also emit
UV-A rays to produce quick tans. However, the energy in UV-A
is weaker than in UV-B. That is why the tan doesn't last long
(ususally disppeared after one to three weeks), and that is
also why UV-A doesn't cause sun-burn on its own.
On the other hand, UV-B's energy is much greater than UV-A's,
and thus, it causes the burning sensation very quickly.
However, the penetration level of UV-B is only upto the
epidermis. Thus, UV-B causes only the epidermal layer(that
is, only one layer) to multiply the production of its melanin
cells. That is why a tan is not produced as instantly as
exposure to UV-A rays. Due to its high energy, UV-B rays once
absorbed into the skin do not deplete quickly, but retained
for a long time. UV-B accumulates to cause a slow 'tan' which
results in delayed pigmentation of the skin(that is, those
unsightly brown blocky patches).
Since both UV-A and UV-B are found in the sun's rays, exposure
to the sun will cause the skin both to tan and to burn - the
tan manifesting faster than the burn as explained above -
appearing as if a tan always precedes a burn. But one can
obtain a tan without a burn(or less degree of burn) by the
following methods:
1. By exposure to a salon's sun-tanning bed(which emits only
UV-A rays).
2. By applying a sunscreen that blocks out only the UV-B
rays(that is preventing a burn caused by the UV-B rays but
allowing the UV-A rays to penetrate the skin to cause the
tan). Some screens even contain active ingredients to speedify
the taning effect, by amplifying the UV-A rays penetration.
There are also suntan products which can amplify tanning -
and within 10 to 15 minutes - under room lighting, without
exposure to the sun. Such products are often named as suntan
lotions(milk, or the like). Note that if one doesn't want to
have a tan as well, then he/she should not apply a suntan
lotion, but a broad spectrum sunscreen lotion instead(meaning
a sunscreen with total block action - blocking UV-A and UV-B).
So do not get mixed up between suntan and sunscreen products.
Sunscreens are available in various strengths, measured in
SPF terms. SPF stands for Sun Protection Factor.
The SPF of a sunscreen is determined by sampling a group of
people by the following steps(usually not less than 25 people
of various skin color tone):
1. The human samples are made to expose their back to the
sun. Most parts of the body are covered, except the parts
which are to be tested and measured. Let's say there are 5
sunscreen products(named A, B, C, D, and E) of varying
anti-UV strengths which need to be measured. Then the person's
back will have 6 holes, cut out from the shirt(or any covering)
exposed to the sun. One hole will have nothing applied on it.
The other five holes will each have one of the five sunscreens
applied, and marked.
2. After every 5 or 10 minutes, the back of the human samples
are examined to determine if a burn has occurred.
To elaborate, let's say after examining one of the human
samples, the unprotected part was found to blister in 10
minutes, while the other 5 parts(on the back of the same
person) each took 100, 150, 180, 200 and 220 minutes
respectively to form the first sign of blisters. The SPF is
then computed by dividing each of these 5 values by 10
minutes(when it was unprotected). Thus, the SPF value for the
5 sunscreens will be:
Sunscreen A = 100/10 = SPF 10
" B = 150/10 = SPF 15
" C = 180/10 = SPF 18
" D = 200/10 = SPF 20
" E = 220/10 = SPF 22
It can be comprehended clearly that SPF is therefore a
measure of the number of times a sunscreen will be able to
protect a person before blister occurs as compared to his/her
exposure to the sun if unprotected.
3. The readings of all the human samples are noted, averaged
and compiled, to provide the SPF values for the respective
sunscreens measured.
Since SPF is a measure of the number of times(and not
absolute hours or minutes), and since such measurement is
conducted on sampling of a small group of people, and taking
their mean value(averages), note that a darker complexioned
person may apply, say, an SPF 10 sunscreen and yet is better
and more effectively protected than one who is fairer-skinned
and wearing an SPF18 sunscreen. Why so? Well, if the darker
complexioned person were to take 30 minutes to blister under
unprotected exposure, then applying an SPF 10 sunscreen will
enable him/her to expose for 300 minutes before blistering
occurs. On the other hand, the fair-skinned person may get
blisters after only 10 minutes of unprotected exposure. So,
an SPF 18 sunscreen will only protect him/her for 180 minutes.
Moreover, every person is different constitutionally. A
person's skin, although applying the same sunscreen, may not
react exactly in the same manner as that which was determined
from the small group of human samples. Yet another factor. The
sampling that was conducted in a cold 4-seasonal climate(even
if done during summer time with lots of sunlight) may not
apply well to people living in the tropical and sub-tropical
climates. Therefore, one may find an SPF sunscreen good for
protecting him/her upto, say, 200 minutes of exposure in a
colder country, but realized that the same sunscreen could
not last longer than 100 minutes at one of the beaches in
Singapore, Malaysia, or Australia. Different times of the year
within one country will also have different amount of UV-A and
UV-B rays, and as such, a sunscreen's protection time will
vary according to the time of the year.
UV-rays are also absorbed and retained in swimming pools and
in sea-water for some time even after the sun has set.
Therefore, swimming immediately after sunset may not be all
that safe as most people presumed. I would recommend morning
swim instead.
Staying at home or carrying an umbrella does not mean that
one is not exposed to any UV rays absolutely. The ground,
the walls, the glass, the surroundings, all reflect light and
UV-rays. So long we are able to see any object(that is objects
are visible to our eyes), there are UV rays present, though in
different degree depending on the time of the day and year.
This is so because we can see only when there's visible ray,
and visible ray is just next to the UV-ray spectrum. Therefore,
whenever there is visible ray, there are UV-rays.
Moreover, higher SPF sunscreen doesn't necessarily mean better
and more effective(especially those containing inorganic
substances). Higher SPF requires higher concentration of UV
absorbers in the sunscreen, and thus a higher risk of
developing skin reaction and allergy. Sunscreens using organic
substances such as TiO2(Titanium Dioxide) is safer, not only
in that it is organic and less susceptible to allergy, but it
also works by deflecting the UV-rays, rather than absorbing
them and retaining on the skin's surface as in cases of
inorganic UV absorbing agents. I believe such retention of
UV-rays on the skin's surface(especially those with higher SPF)
will in the long run promote skin complications too. However,
unfortunately, organic substances alone do not seem to work
more effectively than the synergistic effect of skillfully
combining both organic and inorganic substances.
I hope the above explanation will help you and others in
buying suncare products and in the choice of their relative
SPF values more intelligently and more rationally.
Best Regards: Pierre
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