reviews - Advances in Clinical and Experimental Medicine

reviews - Advances in Clinical and Experimental Medicine

REVIEWS
Adv Clin Exp Med 2009, 18, 5, 519–527
ISSN 1230−025X
© Copyright by Wroclaw Medical University
IRENEUSZ CAŁKOSIŃSKI1, ANDRZEJ GAMIAN1, JOANNA KOBIERSKA−BRZOZA2,
KATARZYNA FITA2, AGNIESZKA CZAJCZYŃSKA−WASZKIEWICZ2, JACEK MAJDA3,
MONIKA CAŁKOSIŃSKA4, OLGA PARULSKA5, MACIEJ DOBRZYŃSKI2
The Influence of Variable Environmental Factors
on Human’s Organism Adaptive Ability
Oddziaływanie zmiennych czynników środowiskowych
na zdolność adaptacyjną organizmu człowieka
1
2
3
4
5
Department of Medical Biochemistry, Wroclaw Medical University, Poland
Department of Conservative Dentistry and Pedodontics, Wroclaw Medical University, Poland
Department of Laboratory Diagnostics, 4th Military Clinical Hospital, Wrocław, Poland
Health Center “Medcom”, Wojkowice, Poland
Department of Maxillofacial Surgery, Wroclaw Medical University, Poland
Abstract
When interpreting the results of laboratory tests in specific patients as false positives, the modifying roles of cli−
matic, ethnicity, diet, and other factors should be taken into account. As there are few reports in the literature about
the reliability of laboratory tests, a study based on multidisciplinary knowledge from such fields as climatology,
anthropology, physiology, and laboratory diagnostics is required. A broad range of environmental factors signifi−
cantly affect the function of the human organism. At the individual level they can modify the values of some diag−
nostic parameters and the course of vital processes and can also influence the general profile of these parameters
in the whole population. Many environmental factors contribute to variability in laboratory results despite mainte−
nance of the same conditions and methods of measurements. The influence of environmental factors may be most
distinctly seen with regard to climatic zone and geography. When differences in daily temperature and light inten−
sity among the seasons are not so prominent, seasonal influences may not cause substantial changes in diagnostic
parameters. However, in climatic zones with significant differences in temperature and hours of daylight during
particular periods of the year, the seasons markedly affect vital processes of the organisms. Circadian and month−
ly rhythms are also essential. Another significant environmental factor is diet, which is usually related to ethnic
affiliation and, through environmental adaptation, correlates with climate. The predominance of certain blood
groups in a population is also a result of environmental adaptation. The effects of environmental factors usually
overlap and intensify one another. Reference values of commonly measured diagnostic parameters reflect only the
norms established for the specific population. Persons from different populations, ethnic groups, or areas of habi−
tation may demonstrate diagnostic values outside the referential ranges, which does not always mean pathology. In
the modern world, in which human migration is very common and much easier than before, this problem has
become more important. It is also significant with regard to commonly performed epidemiological cross−sectional
studies in different populations and subsequent comparisons of results (Adv Clin Exp Med 2009, 18, 5, 519–527).
Key words: reliability of the laboratory tests, environmental factors, diagnostic indices, human organism.
Streszczenie
Interpretując wyniki badań laboratoryjnych pacjenta określane jako fałszywie dodatnie, należy uwzględnić mody−
fikujący wpływ czynników klimatycznych, etnicznych oraz stosowanej diety. W literaturze są jedynie nieliczne do−
niesienia na temat wiarygodności wyników badań laboratoryjnych, dlatego autorzy zauważyli konieczność stwo−
rzenia opracowania łączącego wiedzę z zakresu klimatologii, antropologii, fizjologii oraz diagnostyki laboratoryj−
nej. Szeroko pojęte czynniki środowiskowe w istotny sposób wpływają na funkcjonowanie organizmu. Mogą
modyfikować niektóre wskaźniki diagnostyczne oraz przebieg procesów życiowych u poszczególnych osób, a tak−
że wpływać na charakterystyczny profil w perspektywie całej populacji. Wiele z nich przyczynia się do dużej
zmienności uzyskiwanych wyników mimo zachowania jednakowych warunków badania. Oddziaływanie czynni−
ków środowiskowych najwyraźniej widać w odniesieniu do stref klimatycznych i rejonu zamieszkiwania. Wpływ
520
I. CAŁKOSIŃSKI et al.
poszczególnych pór roku w danej strefie klimatycznej może nie powodować istotnych różnic w wartościach bada−
nych parametrów diagnostycznych, jeżeli różnice temperatury oraz natężenia światła między poszczególnymi po−
rami roku nie są bardzo duże. W strefach klimatycznych, gdzie różnice temperatur i natężenia światła w poszcze−
gólnych okresach roku są znaczne, pory roku znacząco wpływają na procesy życiowe organizmów. Równie istot−
ny jest rytm dobowy, a także rytm okołomiesięczny. Innym ważnym czynnikiem środowiskowym jest dieta, która
wiąże się zwykle z przynależnością do grupy etnicznej i w drodze adaptacji do środowiska koreluje z cechami kli−
matu. Wyrazem adaptacji środowiskowej jest także przewaga określonej grupy krwi w populacji na danym terenie.
Działanie czynników środowiskowych przeważnie wzajemnie się nakłada i potęguje. Przyjęte jako punkt odniesie−
nia wartości referencyjne powszechnie oznaczanych poszczególnych parametrów diagnostycznych odzwierciedla−
ją tylko normę przyjętą dla danej określonej populacji. Osoby badane pochodzące z innych populacji, grup etnicz−
nych lub terenów mogą wykazywać wartości niemieszczące się w zakresie referencyjnym, co nie zawsze musi
oznaczać patologię. W dobie ułatwionego przemieszczania się ludzi oraz zmiany miejsc zamieszkiwania, a także
powszechnie przeprowadzanych epidemiologicznych badań przekrojowych problem ten nabiera coraz większego
znaczenia (Adv Clin Exp Med 2009, 18, 5, 519–527).
A broad range of environmental factors signif−
icantly affects the function of the human organism.
They can modify the values of some diagnostic
parameters and the course of vital processes and
can also influence the general profile of these
parameters in the whole population. At the level of
the individual patient, the normal range estab−
lished for a specific local population may be inap−
propriate for a person from a different geographic
area or climatic zone or consuming a different type
of diet (Fig. 3). Even the levels of parameters in
a given person belonging to a specific population
and inhabiting a certain region may demonstrate
some fluctuations depending on the season of the
year, weather conditions, light intensity, insola−
tion, as well as physiological rhythms such as the
circadian, monthly, and seasonal [14, 18, 20, 22,
25, 26, 40]. In the wider perspective, the specifici−
ty of a particular population resulting from the par−
ticular place of habitation, climatic zone, race, and
diet should be considered, especially when com−
paring data for epidemiological purposes. The
homogeneity of a studied population is also impor−
tant because it restricts the range of reference val−
ues (Figs. 1, 2) [38, 43].
The ranges of reference values for biochemi−
cal and hematological parameters commonly
established for diagnostic purposes are character−
istic for a given population. Values of selected
parameters in persons properly matched for sex
and age are characterized by a narrow range of the
standard deviation, in contrast to results from
a heterogeneous group of persons [33, 44]. Simila−
rly, the average values of parameters derived from
two populations (homogenous and heterogeneous)
can be different (Fig. 1) [8, 35, 37, 38]. A graphi−
cal presentation of the values obtained for a select−
ed parameter on the scale of the whole population
allows defining a symmetric or asymmetric pattern
of the results [11, 41]. This determines the inter−
pretation of the results concerning the defined
group number
Słowa kluczowe: wiarygodność wyników laboratoryjnych, czynniki środowiskowe, wskaźniki diagnostyczne,
organizm.
W
2sd
I
2sd
X
diagnostic parameter concentration
Fig. 1. Figure of reference values of biochemical and
hematological parameters for a homogeneous [W]
(SD ≤ 2) and a heterogeneous population [I] (SD > 2)
Ryc. 1. Rozkład wartości referencyjnych parametrów
biochemicznych i hematologicznych w populacji
homogennej [W] (SD ≤ 2) oraz heterogennej [I]
(SD > 2)
population (dislocation of the histogram to the
right or left along the x−axis, Fig. 2). In an asym−
metric pattern the values are concentrated around
the average, graphically forming a steep line.
A graphical presentation enables showing the
deviation of a single result (Fig. 3) as well as
determining whether a single result is within the
range of reference values characterizing this spe−
cific population [11, 37, 41].
Some environmental factors, such as climate
and geographic location, affect the human organ−
ism and contribute to changes in the values of
some parameters, resulting in their deviation for
the accepted reference values despite the absence
of any pathology (Fig. 3). Several environmental
factors may cause considerable variability in the
level of a parameter despite adherence to the same
conditions of examination. They may affect the
range of the results obtained from individuals
521
number of persons
Environmental Factors and Adaptive Ability
diagnostic parameter concentration
Fig. 2. An example of an asymmetric distribution of
a diagnostic result describing tendencies in a studied
population
number of persons
Ryc. 2. Przykład asymetrycznego rozkładu parametru
diagnostycznego w badanej populacji
er interpretation and avoids errors in diagnostics.
Misinterpretation of laboratory results for a person
from another climatic zone may be an example
(Fig. 3) [10, 17, 36, 38].
Acquaintance with the reference values char−
acterizing a given population is important in mon−
itoring the definite diagnostic indices used for epi−
demiological purposes or for confirming a too low
or high value of the parameter. Factors influencing
selected diagnostic parameters which may lead to
inappropriate interpretation include: the climatic
zone from which the examined person originates;
seasons of the year; temperature; weather stimuli:
weather stress, light intensity, the concentration of
oxygen in the air; diet; electric smog; magnetic
fields of high intensity; genetic adaptation to the
environmental conditions; disturbances in the bio−
logical rhythm.
These factors overlap and intensify one another.
The aim of this study was to evaluate the influ−
ence of environmental conditions and race on
selected diagnostic parameters.
The Influence of
Temperature
on the Human Organism
norm
of diagnostic
parameter
Fig. 3. The most numerous value of a measured para−
meter as well as the range of minimal and maximal
values characterizes a given population (Fig. 1). The
occurrence of values (x) significantly different from
the average value is a false positive and may lead to
interpretive errors, while they do not always indicate
a pathological process
Ryc. 3. Średnia wartość badanego parametru
najliczniej prezentowana oraz zakres wartości maksy−
malnych i minimalnych charakteryzują daną populację
(ryc. 1). Pojawienie się wartości (x), znacząco odbie−
gającej od wartości średniej, jest wynikiem fałszywie
dodatnim i może być przyczyną błędu interpreta−
cyjnego, ale nie zawsze oznacza patologię
belonging to a given population inhabiting a spe−
cific area (Fig. 1) [10, 33]. Reference values pre−
sented in textbooks are unified and they often
neglect the influence of environmental conditions
affecting a population. Hence the usefulness of
such universal ranges of reference values can be
debated because the levels of the measured para−
meters must be compared with the specific range
of values for the particular population to which the
examined individual belongs. This allows a prop−
Temperature is one of the factors creating the
climate of a given zone and influencing the human
organism. It interferes with a human’s adaptive abil−
ity to environmental conditions [14, 15, 18, 19, 26,
30, 34]. Four climatic zones are distinguished [34]:
– the equatorial zone, characterized by an
average temperature of above +20ºC. The seasons
of the year in this zone are defined by the frequency and quantity of rainfall, dividing this zone into
dry and rainy periods;
– the tropical zones, characterized by a mini−
mum temperature of +10–20ºC, with slight summer rainfall;
– the moderate zones, characterized by aver−
age minimum temperatures in the winter from –10
to –20ºC or lower and average temperatures in the
summer of about +20ºC or higher. Waves of frost
and heat are also observed in this zone;
– the polar zones, characterized by average
temperatures in the winter of –30ºC or below and
average temperatures in the two summer months
of about +10ºC.
Considerable differences in the average tem−
perature range among these zones are observed
and they impact the functioning of the human
organism. Many areas of the earth are character−
ized by extreme temperatures (e.g. the difference
between the winter and summer temperatures in
the Gobi Desert are about 80 Cº). Considerable
522
I. CAŁKOSIŃSKI et al.
Table 1. Examples of significant discrepancies in mean
temperatures in European towns
Tabela 1. Przykład znaczących różnic średnich tempe−
ratur w wybranych miastach europejskich
Site
(Miasto)
January
(Styczeń)
July
(Lipiec)
Crete, Greece
(Kreta, Grecja)
12oC
29oC
Ancona, Italy
(Ankona, Włochy)
5.3oC
max 7.9oC
min 2.4oC
24.4oC
max 28.3oC
min 20.1oC
Pula, Croatia
(Pula, Chorwacja)
4oC
28oC
Poznań, west−central 4.8oC
Poland average daily
temperatures based
on several years
of observation
(Poznań, środkowo−
−zachodnia Polska,
średnie temperatury
oparte na kilkuletniej
obserwacji)
Opole, southwest
Poland
(Opole, południowo−
−zachodnia Polska)
–41.2oC (1940)
19oC
40.2oC (1921)
differences are also observed among various locations in Europe and even within the same country,
such as Poland. Here are some examples: the highest average temperature recorded from November
to October 1966 in Ethiopia was +34.6ºC, the
highest temperature in Libya in 1929 was +57.3ºC,
the lowest temperature in Antarctica at Wostok
station recorded between 1961–1990 was –89.2ºC,
and the average temperature in this region was
–55.1ºC [15, 30, 34]. Not only the specific value,
but also the maximum amplitude of temperature is
important. These amplitudes may be tremendous
or slight. For example, the maximum yearly temperature noted in Wierchojansk in Siberia was
106.7ºC. In contrast, on Crete in the Mediterranean zone the average year temperature is about
30ºC (Tab. 1) [15, 30, 34].
The influence of external temperature on the
human organism depends on the adaptive ability to
temperature variations. The variation in temperature
is approximately 50ºC in moderate climate zones.
The range of temperature variation is crucial as well
as its negative and positive values. The temperature
variation in Opole, for example, is about 65ºC and
in Wierchojansk more than 100 Cº [20, 24, 25, 30,
34, 42]. The accommodation of the human organism to temperature variation must include specific
adaptation to temperatures below –5ºC, at which
body fluids freeze. Cases of death by freezing of
homeless people during sudden temperature drops
in autumn and winter periods may indicate a lack of
this ability. Considerably smaller temperature differences, occurring in the range of positive temperatures, are present in the Mediterranean zone and do
not require such adaptation ability (Tab. 1) [30, 34].
Cases of people freezing to death in this zone do not
occur, although cases of hypothermia are observed.
In turn, overheating of the human body related to
higher temperatures is a very common state which
indicates inadequate adaptation of the organism.
The duration of the process is highly important for
the adaptation to negative temperatures [15, 18, 19].
Undoubtedly, the toleration of the human organism
to jumps in temperature is definitely worse [14, 26,
29]. The thermoregulatory mechanisms of individuals living in polar zones mainly include the ability
to adapt to very low negative temperatures. The
specific value does not play as important a role as in
the case of high temperatures. Organisms exposed
to the polar zone do not need to develop adaptation
to temperature values above 0ºC because the ambient temperature do not exceed 15ºC, and that only
for approximately two months in the year [15, 34].
The optimal range of temperatures for Europeans is
between +17 and +23ºC, although there are the
same exceptions for individuals living at the boundaries of climate zones [14, 19, 24, 26].
Nowadays, in an age of considerable climatic
variability, the ability to adapt to short periods of
radically altering temperatures (called temperature
waves) is extremely important [14, 15, 24, 26].
Cold waves are six−day periods with a minimal
average daily temperature of –11ºC [14, 15, 18, 19,
24, 26]. Adaptation of the human body to cold is
a complex process. First, the stimulation of external cold receptors results in sympathetic nervous
system activation, which is related to decreased
levels of adrenalin and noradrenalin in the blood.
A high level of adrenaline affects biochemical
blood parameters, resulting in hyperglycemia and
hyperlipidemia. In the second phase of adaptation
the hypothalamic-pituitary-adrenal (HPA) axis is
activated. At this stage, corticoliberin (corticotrophin-releasing hormone, CRH) activates the
secretion of ACTH (adrenocorticotropic hormone),
which consequently stimulates the adrenal cortex
for cortisol production and release to the blood.
The level of cortisol is much higher than under
conditions of optimal temperature. The increased
concentration of TSH (thyroptropin) results in the
activation of the thyroid gland to produce higher
amounts of T3 and T4, which are subsequently
released to the bloodstream. In the process of cold
adaptation, a decreased concentration of vasopressin in the blood is observed. As a result of hormonal changes and the catabolic way of its action
and the advantage of the sympathetic system, an
Environmental Factors and Adaptive Ability
increase in metabolic activity is observed which is
connected with increased oxygen intake. The latter
is compensated by more effective oxygen binding
by hemoglobin, which causes its higher oxygenation. Increased secretion of chloride, sodium ions,
and urea is observed in individuals living in cold
regions. Low temperatures also influence the transport properties of mucosa and the increased resistance of peripheral vessels, particularly in the
regions exposed to the cold, with decrease oxygenation of certain tissues as well as the removal of
metabolites. Increased resistance results in increased diastolic blood pressure, whereas increased
levels of hormones demonstrating lipolytic action
cause an increase in the concentrations of lipids
and cholesterol in the blood. The values of ESR
(erythrocyte sedimentation rate) decrease at low
temperatures and the blood coagulation time is
shortened. Decreased tissue permeability is also
observed. Higher acidity of gastric juices is caused
by the increased secretion of hydrochloric acid. In
a population living in a polar climatic zone, behavioral mechanisms adapting the organism to the low
temperatures are observed. This is related to
anthropological features such as decreased height,
decreased body surface-to-mass ratio, decreased
ear and nose sizes, and the presence of significant
subsurface fat tissue.
Another aspect is adaptation of the human
body to a hot climate. Two issues are of great
importance: accommodation to the high tempera−
ture of the environment and rapid adaptation to
heat waves. A heat wave is a six−day period with
an average daily temperature above 30ºC [14, 15,
18, 19, 24, 26]. It was found that living in a hot climate results in decreases in blood hemoglobin and
gamma-globulin concentrations, while phosphate
concentrations increase in the blood serum. On the
other hand there are increased blood adrenal
steroid concentrations, similar to those observed
as a reaction to low temperatures. Additionally,
decreased diuresis results in increased blood volume and reduced peripheral and vessel resistance.
As a result of the influence of heat on the skin,
blood flow is increased and vessel resistance is
decreased, which causes a lowering of diastolic
blood pressure. In warm climates, gastric juice
secretion and its acidity are also decreased.
The Influence
of the Seasons
on the Human Organism
The influence of the seasons in certain climate
zones on diagnostic parameters can be quite limit−
523
ed if the temperature and light intensity do not dif−
fer much from season to season, which is the case
of the Mediterranean climate, in which long−term
decreases in temperature below 0ºC are not
observed [30, 34]. There are certain similarities in
the characteristics of some climate zones, for
example the equatorial and tropical [30, 34].
However, in the climate zones where significant
seasonal variations in temperature and light intensity occur, seasonal changes in life processes are
observed and, consequently, changes in diagnostic
parameters. This concerns the moderate and polar
climate zones [15, 34], where high temperatures,
light intensity, and sun visibility occur as well as
low temperatures. The average monthly length of
sun visibility is 132 hours and light intensity is in
the range of 1.46 MJ/m2 in this climate zone.
However, there are regions in this zone where
these parameters are much lower, for example at
the end of November and beginning of December,
when insolation is minimal or absent [3, 20–22,
24–27].
Depending on the location on the globe, there
are five zones of sun exposure. The first two are
called deficit zones and cover the regions from the
poles to the respective latitudes of 55.7º. The second two are called the optimal sun exposure zones
and cover the regions from 57.5 to 42.5º latitude.
The fifth zone is called the zone of excess sun exposure and covers the region from the latitudes of
42.5º on either side of the equator [15, 23, 24, 26].
All parameters characterizing seasons, such
the day length, light intensity, sun exposure, and
the air temperature related to them, influence tem−
perature (cold and heat) receptors and the eye reti−
na in many ways and consequently change the
metabolism of the organism. The sum of the
effects of all climatic factors on the living organ−
isms’ receptors in a given season causes changes
in the activities of the autonomic nervous and
endocrine systems [19, 22–26]. At the latitude of
Poland, the superiority of the sympathetic nervous
system is observed from the middle of February to
the end of August, whereas the parasympathetic
nervous system dominates from September to
January. At the geographic latitude of Poland the
seasons influence the activity of the endocrine sys−
tem. Large differences in the concentration of
gonadotrophic hormones in the blood between
summer and winter are observed. The higher lev−
els of hormones during the summer are related to
the stimulation of the eye retina by higher light
intensity, resulting in increased secretion of
hypophyseal FSH, which activates the secretion of
testosterones and estrogens. This process is called
the Benoit−Miline effect [23, 26, 27]. The increase
in light intensity during the early spring causes, by
524
I. CAŁKOSIŃSKI et al.
the increased concentration of gonadotrophins in
the blood, increased psychophysical activity and
metabolic processes in the organism (anabolic
action on proteins) [23, 24, 27]. Blood production
processes are activated as well. Increased hemo−
globin level in erythrocytes as well as increased
calcium, magnesium, and phosphorous ion con−
centrations in the blood are observed. Moreover,
melanin is oxygenated and vitamin D3 and hista−
mine synthesis are activated. The increase in sun
exposure causes higher thyroid and adrenal gland
activity and increases the secretion of gastric
juices. The seasons influence the blood’s composi−
tion. Lower levels of hemoglobin are observed in
summer. Decreased values of this parameter also
occur during heat waves. The maximal increase in
platelet and eosinophil numbers is in the early
spring (March and April), whereas their lowest
levels are observed in summer (July and August).
In February there is an increase in the values of
hematocrit and the erythrocyte sedimentation rate
(ESR), of which the lowest values are noted in the
summer (July, August). This is related to the
increase in blood volume during this season. The
concentration of albumin is lower in the spring
than in the other seasons, as are the levels of glob−
ulins. In autumn (September to December) the
decrease in the levels of prothrombin is pro−
nounced. The serum concentration of phosphates
and potassium reveals minimal values in winter
(February) and maximal in summer and autumn.
The concentration of glycocorticosteroids signifi−
cantly deceases in the spring and autumn, whereas
their increase is observed in winter and summer.
Visible increases in lipid and cholesterol levels in
blood serum are observed at the turn from autumn
to winter, which correlates significantly with the
lowering of temperature and shortening of day−
light [14, 18, 26, 42]. A phenomenon known as
weather stress is associated with the occurrence of
heat and cold waves or atmospheric fronts (espe−
cially atmospheric depressions). They significant−
ly influence diagnostic parameters. Weather stress
may cause such psychosomatic symptoms as local−
ized pain, vegetative dystonia, sleeping disorders,
and timidity. The decrease in blood pressure associ−
ated with these conditions may be responsible for
some alterations in blood characteristics related to the
increased level of leukocytes. After the cold wave,
bleeding time and coagulation time are shortened.
The Influence
of Altitude on Humans
The significance of this factor is visible espe−
cially in relation to the mountain climate. It is
assumed that a mountain climate occurs in regions
located over 500 m above sea level [15, 34]. In this
climate the pressure of the oxygen in the air
decreases with increasing altitude. Adaptation to
these conditions is expressed by increased erythro−
cyte count, Hb concentration, and hematocrit val−
ues as well as a greater saturation. Elevated levels
of glycocorticosteroids in the blood also occur.
These changes are associated with increased blood
pressure, pulse acceleration, and enhanced lung
ventilation per minute [15, 18, 19].
Other Selected
Environmental Factors
Contributing
to the Function
of the Human Organism
The next important factor is the day and night
rhythm [18, 19]. It is determined by the light and
dark cycle and may be disturbed when changing
the time zone. Various diagnostic parameters reach
their maximal or minimal values at specific times
of the day and night rhythm, which should be
taken into consideration when the time of taking
samples of blood or urine is scheduled or the
results are interpreted [18, 19]. Seasonal and
monthly rhythms are also important. The monthly
rhythm is related to the moon phases, while the
seasonal rhythm is associated with the prolonga−
tion or shortening of daylight hours, which has
bearing on the predominance of the sympathetic or
the parasympathetic system. The management of
some hormones, such as gonadotrophins or thy−
roid hormones, are under the influence of these
rhythms.
One very important factor which can modify
diagnostic values of parameters is diet. Diet is
determined by inhabitance of a specific geograph−
ic region and climatic zone, economic and social
status, as well as cultural and ethnic background.
The specific type of diet used for a long period of
time may considerably alter the levels of diagnos−
tic parameters [1, 2, 4, 5, 12, 13, 40]. These levels
may also be modified by episodic changes in diet
caused by travel, changing the place of residence,
or lifestyle. This refers especially to the concentra−
tions of glucose, cholesterol, and uric acid. Diet is
usually related to ethnic affiliation and, by adapta−
tion to the environment, correlates with the char−
acteristics of the climate [4, 12, 31, 39, 45]. The
Mediterranean diet can serve as an example. It is
characterized by a large amount of vegetables and
unsaturated fats. The populations inhabiting this
region have low serum concentrations of choles−
Environmental Factors and Adaptive Ability
terol and triglycerides, which is attributed to this
type of diet. In contrast, the diet of the Inuit
(Eskimos), containing saturated and unsaturated
fats from fish and sea mammalians and a low
amount of vegetables, is evidence for adaptation to
low temperatures. However, avitaminoses C, D,
and B do not occur in this population because this
specific diet effectively prevents deficiency of
these vitamins. It is rich in omega−3 fatty acids,
which play an important role in preventing cardio−
vascular disorders such as atheromatosis and
ischemic heart disease. It contributes to a low con−
centration of cholesterol and decreased blood
platelet counts, diminishing their aggregation and
prolongation of coagulation time. However, this
diet composed mainly of sea animals carries the
risk of accumulation of significant amounts of per−
sistent organic pollutants such as dioxins, with
consequences such as impaired immunologic
response to infections and possible thyroid dys−
function and sexual hormone disorders [6, 7, 9].
These mechanisms of adaptation which allow the
functioning of organisms under specific conditions
may not work in a situation of sudden change in
lifestyle, including diet [12, 31]. This was clearly
observed in Native American and Inuit popula−
tions moving from their traditional diet to a fast−
food diet. They subsequently became prone to the
typical civilization diseases which they had never
experienced before. Similarly, the Inuit diet would
cause in Caucasians the risk of metabolic disorders
associated with ketosis because of the lack of car−
bohydrates [28, 32].
Assessing the results obtained from blood
samples or other materials, attention should be
paid to the origin of the examined person because
the measured parameters may sometimes not be
within the established range of reference values
used for the population inhabiting the given
region. For example, a population living in high
mountain areas (Tibet) is characterized by consid−
erably elevated erythrocyte indexes, which reflect
adaptation to the environmental conditions.
Sherpa people living in mountain villages of Tibet
reveal the ability to isolate hypothermia, related to
cooling the body surface without any changes in
metabolic processes, which protects them from
catching cold. The Inuit have a basic metabolism
30% higher than Europeans living under the same
conditions. The populations inhabiting tropical
zones, where the rhythm of light and dark is rela−
tively stable and temperature fluctuations are not
so large (exceeding the thermal optimum for
Europeans), demonstrate decreased body weight−
525
to−surface ratios and an increased number of sweat
glands [14, 15, 18, 19, 24, 26].
The predominance of specific blood groups in
given areas is also a sign of adaptation to prevailing
conditions. Some blood group properties [16, 38]
cause better resistance to certain diseases. The
common prevalence of thalasemia in some popu−
lations of Africans protects them from malaria.
The role of the anthropological factor is also
important in the statistical occurrence of blood
groups in the ABO system. Group O occurs in sig−
nificant percentages, sometimes reaching 100% in
Native Americans of South America and the
northeastern states of the USA and in the Inuit.
These populations demonstrate a relatively small
proportion of people with group A and a lack of
group B. Group A is the most prevalent in the abo−
rigines of southern Australia, where group B does
not occur at all. In some populations, such as the
Australian, Polynesian, Melanesian, Hindu, Inuit,
Chinese, and Japanese, group A includes only sub−
group A1, whereas subgroup A2 is also observed
in the white and black race of Africa. Group B is
most strongly represented in Asia. In the Rh blood
group system it was established that the group Rh−
is determined by the recessive antigens c, d, and
e and appears in the Caucasian race, but not in
black and yellow races. Another example of adap−
tation is the amount of pigment in the skin.
Scandinavians inhabiting the region with poor
insolation are characterized by little pigment in the
skin. Consequently their skin is less susceptible to
UV radiation. The great intensity of UV radiation
occurs in tropical and subtropical zones. Race is
also a form of adaptation and a factor which diver−
sifies populations [17]. The black race, for exam−
ple, demonstrates lowered levels of leukocytes,
lymphocytes, and monocytes as well as hemat−
ocrit, MHCH, and MCH which are physiological−
ly absolutely normal in this population [36].
The authors concluded that widely compre−
hended environmental factors may significantly
contribute to the vital functions of the human organ−
ism, resulting in their modifications and adaptation
to prevailing needs and conditions. The final result
of this influence is the sum of the particular over−
lapping effects. The values accepted as references
only reflect the norms for a specific population.
Individuals belonging to other populations or ethnic
groups or living elsewhere may present results
which are not within the reference range but which
are not always evidence of pathology. In these times
of increased human migration, this problem occurs
more frequently and should be considered.
526
I. CAŁKOSIŃSKI et al.
References
[1] Andreadou I, Iliodromitis EK, Mikros E, Constantinou M, Agalias A, Magiatis P, Skaltsounis AL, Kamber E,
Tsantili−Kakoulidou A, Kremastinos DT: The olive constituent oleuropein exhibits anti−ischemic, antioxidative,
and hypolipidemic effects in anesthetized rabbits. J Nutr 2006, 136, 2213–2219.
[2] Belanger MC, Dewailly E, Berthiaume L, Noel M, Bergeron J, Mirault ME, Julien P: Dietary contaminants
and oxidative stress in Inuit of Nunavik. Metabolism 2006, 55, 989–995.
[3] Błażejczyk K: Bioklimatyczne uwarunkowania rekreacji i turystyki w Polsce. Prace geograficzne. PAN IG i PZ
Warszawa 2004, 192.
[4] Briante R, Febbraio F, Nucci R: Antioxidant properties of low molecular weight phenols present in the mediter−
ranean diet. J Agric Food Chem 2003, 51, 6975–6981.
[5] Burlingame B: The food of Near East, North West and Western African regions. Asia Pac J Clin Nutr 2003, 12,
309–312.
[6] Całkosiński I: The course of experimentally induced acute pleuritis with use of Nitrogranulogen (NTG) and
2,3,7,8−tetrachlorodibenzo−p−dioxin (TCDD). Habilitation Thesis, Wroclaw Medical University 2005.
[7] Carpenter DO, de Caprio AP, O’Hehir D, Akhtar F, Johnson G, Scrudato RJ, Apatiki L, Kava J,
Gologergen J, Miller PK, Eckstein L: Polychlorinated biphenyls in serum of the Siberian Yupik people from St.
Lawrence Island, Alaska. Int J Circumpolar Health 2005, 64, 322–335.
[8] Cembrowski GS, Juco JW: Establishing and verifying reference intervals. Check Sample Clinical Chemistry 39
(7). Chicago, III: American Society of Clinical Pathology 1999.
[9] Cote S, Ayotte P, Dodin S, Blanchet C, Mulvad G, Petersen HS, Gingras S, Dewailly E: Plasma organochlo−
rine concentrations and bone ultrasound measurements: a cross−sectional study in peri− and postmenopausal Inuit
women from Greenland. Environ Health 2006, 5, 33.
[10] Nussey DH, Wilson AJ, Brommer JE: The evolutionary ecology of individual phenotypic plasticity in wild pop−
ulations. J Evol Biol 2007, 20, 831–844.
[11] Murphy EA: A Companion to Medical Statistics. The Johns Hopkins University Press, Baltimore 1985.
[12] Ebbesson SO, Risica PM, Ebbesson LO, Kennish JM, Tejero ME: Omega−3 fatty acids improve glucose tol−
erance and components of the metabolic syndrome in Alaskan Eskimos: the Alaska Siberia project. Int
J Circumpolar Health 2005, 64, 396–408.
[13] Fki I, Bouaziz M, Sahnoun Z, Sayadi S: Hypocholesterolemic effects of phenolic−rich extracts of Chemlali olive
cultivar in rats fed a cholesterol−rich diet. Bioorg Med Chem 2005, 13, 5362–5370.
[14] McMichael A, Woodruff R, Hales S: Climate change and human health: present and future risks. Lancet 2006,
367, 859–869.
[15] Tout DG: Biometeorology. Progress in Physical Geography 1987, 11, 473–486.
[16] Feder LK, Park MA: Human Antiquity: An Introduction to Physical Anthropology and Archaeology. McGraw−
−Hill 2006.
[17] Ka−Wing Cheng C, Chan J, Cembrowski GS, van Assendelft O: Complete Blood Count Reference Interval
Diagrams Derived from NHANES III: Stratification by Age, Sex, and Race. Lab Hematolog 2004, 10, 42–53.
[18] Kiełczewski B, Bogucki J: Zarys biometeorologii sportu. Sport i Turystyka Warszawa 1972, 169, 175, 180.
[19] Kozłowski S, Nazar K: Wprowadzenie do fizjologii klinicznej. PZWL, Warszawa 1984, 508–525, 527–533,
551–554.
[20] Kozłowska−Szczęsna T: Problemy Bioklimatologii Uzdrowiskowej. PAN IG i PZ, Warszawa 1975, 3–4, 15.
[21] Kozłowska−Szczęsna T: Problemy Bioklimatologii Uzdrowiskowej. PAN IG i PZ, Warszawa 1981, 2, 88.
[22] Kozłowska−Szczęsna T: Problemy Bioklimatologii Uzdrowiskowej. PAN IG i PZ, Warszawa 1984, 1–2,
117–138.
[23] Kozłowska−Szczęsna T, Błażejczyk K: Promieniowanie słoneczne i jego wpływ na organizm człowieka. Baln
Pol 1998, 40, 130–141.
[24] Kozłowska−Szczęsna T, Błażejczyk K, Krawczyk B: Bioklimatologia człowieka. PAN IG i PZ, Warszawa 1997, 1.
[25] Kozłowska−Szczęsna T, Błażejczyk K, Krawczyk B, Milanówka D: Bioklimat uzdrowisk polskich i możliwoś−
ci jego wykorzystania w lecznictwie. PAN IG i PZ, Warszawa 2002, 3, 611.
[26] Kozłowska−Szczęsna T, Krawczyk B, Kuchcik M: Wpływ środowiska atmosferycznego na zdrowie
i samopoczucie człowieka. PAN IG i PZ, Warszawa 2004, 4.
[27] Kuczmarski M: Usłonecznienie Polski i jego przydatność dla helioterapii. PAN IG i PZ, Warszawa 1990, 4.
[28] Lambden J, Receveur O, Marshall J, Kuhnlein HV: Traditional and market food access in Arctic Canada is
affected by economic factors. Int J Circumpolar Health 2006, 65, 331–340.
[29] Malchaire JB: Predicted sweat rate in fluctuating thermal conditions. Eur J Appl Physiol 1991, 63, 282–287.
[30] Martyn D: Klimaty kuli ziemskiej. PWN, Warszawa 1995, 57, 78–93, 118, 123.
[31] McLaughlin J, Middaugh J, Boudreau D, Malcom G, Parry S, Tracy R, Newman W: Adipose tissue triglyc−
eride fatty acids and atherosclerosis in Alaska Natives and non−Natives. Atherosclerosis 2005, 181, 353–362.
[32] Moustgaard H, Bjerregaard P, Borch−Johnsen K, Jorgensen ME: Diabetes among Inuit migrants in Denmark.
Int J Circumpolar Health 2005, 64, 354–364.
[33] Neumeister B, Besenthal I, Liebich H: Diagnostyka laboratoryjna. Urban & Partner, Wrocław 2001, 15, 472.
[34] Olivier JE: Climate and Man’s Environmental. John Wiley & Sons, Inc 1993.
[35] Ramirez G, Bittle PA, Colice GL, Herrera R, Agosti SJ, Foulis PR: The effect of cigarette smoking upon
hematological adaptations to moderately high altitude living. J Wilderness Med 1991, 107, 64–67.
Environmental Factors and Adaptive Ability
527
[36] Reed WW, Diehl LF: Leukopenia, neutropenia, and reduced hemoglobin levels, in healthy American blacks.
Arch Intern Med 1991, 151, 501–505.
[37] Rogulski J: Wiarygodny wynik laboratoryjny – dlaczego i po co? Diagn Lab 1994, 30, 11–20.
[38] Saxena S, Wong ET: Heterogeneity of common hematologic parameters among racial, ethnic and gender sub−
groups. Arch Pathol Lab Med 1990, 114, 715–719.
[39] Simopoulos AP: The Mediterranean diets: What is so special about the diet of Greece? The scientific evidence.
J Nutr 2001, 131, 3065–3073.
[40] Singh I, Mok M, Christensen AM, Turner AH, Hawley JA: The effects of polyphenols in olive leaves on
platelet function. Nutr Metab Cardiovasc Dis 2008, 18, 127–132.
[41] Stanisz A: Przystępny kurs statystyki w oparciu o program Statistica PL na przykładach z medycyny. Stafsaft
Kraków 1998, 91.
[42] Kożuchowski K, Wibig J, Degirmendžić J: Meteorologia i klimatologia. PWN, Warszawa 2007.
[43] van den Bosche J, Devreese K, Malfait R: Reference intervals for a complete blood count determined on dif−
ferent automated haematology analysers: Abx Pentra 120 Retic, Coulter Gen−S, Sysmex SE 9500, Abbott Cell
Dyn 4000 and Bayer Advia 120. Clin Chem Lab Med 2002, 40, 69–73.
[44] Wissenschaftliche Tabellen Geigy, Ciba−Geigy Limited. Basetle Switzerland, 1979.
[45] Zdrojewicz Z, Sieja A, Dobrzyński M, Szumny A: Sirtuina – budowa, działanie, znaczenie kliniczne. Probl Ter
Monit 2006, 17, 259–262.
Address for correspondence:
Ireneusz Całkosiński
Department of Medical Biochemistry
Wroclaw Medical University
Chałubińskiego 10
50−368 Wrocław
Poland
Tel.: +48 71 784 13 70
E−mail: [email protected]
Conflict of interest: None declared
Received: 30.03.2009
Revised: 6.08.2009
Accepted: 7.09.2009