Title: Diapositiva 1
1Prevention of Refractive Defects of Vision by
Means of Evolutionary Medicine Libertini G.
(M.D., Independent Researcher)
2
1
3
Evolutionary Medicine is not an Alternative
Medicine (like homeopathy, iridology, ayurvedic
medicine, naturopathy, traditional Chinese
medicine, energy medicine, etc.) but a Medicine
that is more thoroughly scientific in that it
involves the concepts of Evolutionism.
Evolutionary Medicine involves many concepts and
applicative consequences. Here, I develop a
practical application of a simple concept, the
mismatch 1,2, to the genesis of refractive
defects of vision.
A medicine that ignored the principles of
chemistry, for example, would be partially
scientific. Similarly, a medicine that
ignores the principles of evolution is partially
scientific.
What is Evolutionary Medicine? Evolutionary or
Darwinian Medicine 1-6 comes into being in 1991
1, but there are some known forerunners 7
(e.g. 8) and others not generally cited as
forerunners 9,10.
The concept of mismatch is simple but with huge
implications
If a species is adapted to a certain range of
conditions (including diet, environmental
conditions, interrelations with other living
beings, etc.), called for brevity ecological
niche, any change in the ecological niche
potentially is a source of disfunctions
(diseases), because there is no adaptation to the
new conditions. This is defined as "mismatch.
1 Williams GC, Nesse RM (1991) The dawn of
Darwinian medicine. Quart. Rev. Biol. 66,
1-22. 2 Nesse RM, Williams GC (1994) Why we get
sick. New York (USA), Times Books. 3 Stearns SC
(ed) (1999) Evolution in health and disease (1st
ed.). Oxford (UK), Oxford University Press. 4
Trevathan WR, Smith EO, McKenna JJ (eds) (1999)
Evolutionary Medicine. New York (USA), Oxford
University Press. 5 Trevathan WR, Smith EO,
McKenna JJ (eds) (2008) Evolutionary Medicine
new perspectives. New York (USA), Oxford
University Press. 6 Stearns SC, Koella JC (eds)
(2008) Evolution in health and disease (2nd ed.).
Oxford (UK), Oxford University Press. 7
Trevathan WR, Smith EO, McKenna JJ (2008)
Introduction and overview of Evolutionary
Medicine. In Trevathan WR, Smith EO, McKenna JJ
(eds) Evolutionary Medicine new perspectives.
New York (USA), Oxford University Press. 8
Eaton SB, Shostak M, Konner M (1988) The
paleolithic prescription a program of diet
exercise and a design for living. New York (USA),
Harper Row. 9 Price WA (1939) Nutrition and
Physical Degeneration. New York London, Paul B.
Hoeber. 10 Libertini G (1983) Ragionamenti
Evoluzionistici. Naples (Italy), Società Editrice
Napoletana English Edition (2011) Evolutionary
Arguments, Crownsville (USA), Azinet Press.
So, the contrast is not between current medicine
and alternative medicines but between current
medicine (which in most cases ignores
Evolutionism) and Evolutionary Medicine (which is
a more thoroughly scientific medicine)
1 Eaton SB, Shostak M, Konner M (1988) The
paleolithic prescription a program of diet
exercise and a design for living. New York (USA),
Harper Row. 2 Libertini G (2009) Prospects of
a Longer Life Span beyond the Beneficial Effects
of a Healthy Lifestyle, in Bentely JV, Keller MA
(eds) Handbook on Longevity Genetics, Diet
Disease, New York (USA), Nova Science Publishers
Inc.
Is this difference only a theoretical / verbal
nicety? or Does this difference have strong and
significant implications for the structure of
medical studies and for health organization?
5
6
4
Refractive Defects of Vision in the Context of
Evolutionary Medicine
-
- - varying greatly within the same population with
changing conditions 1-3 - varying greatly within a population over a short
time 2,4,5 (see Figure)
Step 2 - Comparison between the frequency of a
disease in modern populations and the frequency
of the same disease in populations in primitive
conditions The study of primitive peoples shows
that these defects are very rare or nonexistent
among them. As regards Australian Aborigenes
The marvelous vision of these primitive people
is illustrated by the fact that they can see many
stars that our race cannot see. In this
connection it is authoritatively recorded
regarding the Maori of New Zealand that they can
see the satellites of Jupiter which are only
visible to the white man's eye with the aid of
telescopes. These people prove that they can see
the satellites by telling the man at the
telescope when the eclipse of one of the stars
occurs. It is said of these primitive Aborigines
of Australia that they can see animals moving at
a distance of a mile which ordinary white people
can not see at all. 1 As regards Yakuts (a
Siberian people) Many travelers observed what
some of them call telescopic eyesight among
these peoples. A Yakut distinguished with the
naked eye stars in the Pleiades not usually seen
without a telescope. The Yakuts say there are
many stars in this group, but only seven large
ones 2
Step 1 - Epidemiological study of modern
populations Refractive defects (myopia,
astigmatism and hyperopia) are a group of related
diseases with frequency - very common 1-3 -
varying greatly from population to population
(e.g. The prevalence of myopia in Asia is as
high as 70-90, in Europe and America 30-40, and
in Africa 10-20 1)
(From 2) Figure 1. Moderate myopia (1.005.00
D) by age in Indians and Eskimos of the Yukon and
NorthWest territories. Adapted from Morgan
Munro (1973) (5)
1 Rose KA , Morgan IG, Smith W, Burlutsky G,
Mitchell P, Saw S-M (2008) Myopia, lifestyle, and
schooling in students of Chinese ethnicity in
Singapore and Sydney. Arch. Ophthalmol. 126,
527-30. 2 Cordain, L, Eaton, SB, Miller, JB,
Lindeberg, S, Jensen, C (2002) An evolutionary
analysis of the aetiology and pathogenesis of
juvenile-onset myopia. Acta Ophthalmol. Scand.
80, 12535. 3 Garner LF, Owens H, Kinnear RF,
Frith MJ. (1999) Prevalence of myopia in Sherpa
and Tibetan children in Nepal. Optom. Vis. Sci.
76, 282-5. 4 Edwards MH, Lam CS (2004). The
epidemiology of myopia in Hong Kong. Ann. Acad.
Med. Singapore. 33, 34-8. 5 Morgan, RW, Munro,
M (1973) Refractive problems in northern natives.
Can. J. Ophthalmol. 8, 2268.
1 Fredrick DR (2002) Myopia. BMJ. 324,
1195-9. 2 Dirani M et al. (2010) Prevalence of
refractive error in Singaporean Chinese children
the strabismus, amblyopia, and refractive error
in young Singaporean Children (STARS) study.
Invest. Ophthalmol. Vis. Sci. 51, 1348-55. 3
Chow YC, Dhillon B, Chew PT, Chew SJ (1990)
Refractive errors in Singapore medical students.
Singapore Med. J. 31, 4723.
- 1 Price, WA (1939) Nutrition and Physical
Degeneration. New York London, Paul B. Hoeber. - 2 De Hutorowicz H, Adler BF (1911) Maps of
Primitive Peoples. Bull. Amer. Geogr. Soc. 43,
669-79. -
7
8
9
Step 3 - Hypotheses on the possible changes in
the ecological niche underlying the disease and
on possible pathogenetical mechanisms Excessive
near work, especially using artificial lighting,
an improbable condition in the ecological niche
to which we are adapted, is a common hypothesis
regarding the causes of refractive defects, in
particular myopia 1,2. Against this hypothesis
In an earlier study of 977 school children (617
years of age) on the remote South Pacific island
of Vanuatu, Garner et al. (1985) found that only
1.3 of subjects had myopia greater than -?0.25
D, despite engaging in about 8 hrs of school work
per day. 3 Another hypothesis ascribes the
epidemic of myopia incidence to dietary
alterations, in particular the increase in high
glycaemicload foods 3. But, in two homogeneous
populations with no detectable difference in
dietary habits, incidence of myopia was very
different 4.
A study was made of two homogeneous groups of
6-7-years old children of Chinese ethnicity,
living in Singapore and in Sidney, respectively,
with the same frequency of myopia in their
parents Children in Sidney read more books per
week (P lt .001) and did more near-work activity
(P .002). Children in Sidney spent more time on
outdoor activities (13.75 vs 3.05 hours per week)
(P lt .001). The prevalence of myopia was 3.3 in
Sidney and 29.1 in Singapore 1. This suggests
that the critical factor is the outdoor activity,
alias the exposition to natural light, a
hypothesis confirmed by other studies 2,3. In
particular Higher levels of total time spent
outdoors, rather than sport per se, were
associated with less myopia 2. In these
studies, near-work activities appeared to be an
independent aggravating factor, but not the main
cause of myopia 2,3.
As regards two hunter-gatherer populations
Using a retinoscope and cycloplegia, Holm
(1937) refracted 2364 members (aged 2065 years)
of several hunter-gatherer tribes in Gabon
(formerly French Equatorial Africa) in 1936. Of
the 3624 eyes examined, only 14 were classified
as myopic (nine eyes from -?0.50 to 1.00 D five
eyes from -?3.00 to -?9.00 D), thereby yielding a
myopia incidence rate of 0.4. Similar low rates
for myopia were reported by Skeller (1954), who
refracted the eyes of 775 Angmagssalik Eskimos as
part of a comprehensive anthropological study
carried out in 1954. Retinoscopy in conjunction
with cycloplegia demonstrated that of the 1123
eyes examined, only 13 (1.2) were classified as
myopic (nine eyes -?1.00 D four eyes -?1.25
D). 1
a number of lines of evidence strongly reject
the notion that a recent (in evolutionary
terms) relaxation of natural selection pressures
could be responsible for the high incidence of
myopia in modern, technological societies.
1 Data from Step 1 and Step 2 indicate that
refractive defects are surely a group of diseases
caused by environmental factors, i.e. by
presumable mismatch phenomena.
1 Zylbermann R, Landau D, Berson D (1993) The
influence of study habits on myopia in Jewish
teenagers. J. Pediatr. Ophthalmol. Strabismus 30,
31922. 2 McBrien NA, Adams DW (1997) A
longitudinal investigation of adult-onset and
adult-progression of myopia in an occupational
group. Refractive and biometric findings. Invest
Ophthalmol. 38, 32133. 3 Cordain L, Eaton SB,
Miller JB, Lindeberg S, Jensen C (2002) An
evolutionary analysis of the aetiology and
pathogenesis of juvenile-onset myopia. Acta
Ophthalmol. Scand. 80, 12535. 4 Rose KA ,
Morgan IG, Smith W, Burlutsky G, Mitchell P, Saw
S-M (2008) Myopia, lifestyle, and schooling in
students of Chinese ethnicity in Singapore and
Sydney. Arch. Ophthalmol. 126, 527-30.
1 Rose KA, Morgan IG, Smith W, Burlutsky G,
Mitchell P, Saw SM (2008) Myopia, lifestyle, and
schooling in students of Chinese ethnicity in
Singapore and Sydney. Arch. Ophthalmol. 126,
527-30. 2 Rose KA, Morgan IG, Ip J, Kifley A,
Huynh S, Smith W, Mitchell P. (2008) Outdoor
activity reduces the prevalence of myopia in
children. Ophthalmol. 115, 1279-85. 3 Dirani M,
Tong L, Gazzard G, Zhang X, Chia A, Young TL,
Rose KA, Mitchell P, Saw SM. (2009) Outdoor
activity and myopia in Singapore teenage
children. Br. J. Ophthalmol. 93, 997-1000.
- 1 Cordain, L, Eaton, SB, Miller, JB, Lindeberg,
S, Jensen, C (2002) An evolutionary analysis of
the aetiology and pathogenesis of juvenile-onset
myopia. Acta Ophthalmol. Scand. 80, 12535. -