Файл: Medical_Myths_Lies_and_Half-Truths_guidebook.pdf

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autism

: (Now considered part of autism spectrum disorder.) Autism 

is a neurodevelopmental disorder characterized by a de

¿

 cit of social 

development. While the precise cause is unknown, current evidence strongly 
suggests autism is largely a genetic disorder affecting brain development. 
There is no scienti

¿

 c evidence linking autism to a signi

¿

 cant environmental 

factor, including parenting style, speci

¿

 c foods (such as dairy products) or 

toxins (Lecture 7). Despite some credulous media coverage, multiple studies 
have failed to show any correlation between vaccines and autism. Also, 
despite claims by a few, mercury toxicity is a distinct neurological condition 
that does not resemble autism (Lecture 11).

bacteria

: Bacteria are the most populous kingdom of life on earth. Most 

bacteria do not cause disease or have any implications for human health 
(Lecture 6). Some bacterial species are actually necessary for health, as 
they colonize our skin, bowels, and other mucous membranes. Only a small 
percentage of bacterial species are infectious to humans and can cause 
illness. Illnesses such as 

À

 us and colds are not caused by bacteria, but rather 

by viruses (Lecture 9). There are vaccines available for certain common 
and serious bacterial infections. Attenuated bacteria are used in typhoid 
and tuberculosis (TBG) vaccines, while killed bacteria are used in typhoid, 
cholera, plague, and pertussis vaccines (Lecture 10). 

See also

probiotics

.

bee venom therapy

: Bee venom therapy involves allowing honey bees to 

sting and inject their venom, which is believed to have anti-in

À

 ammatory 

properties. While bee venom contains many interesting biologically 
active chemicals, there is currently no evidence supporting the safety and 
effectiveness for bee venom for any speci

¿

 c disease. Bee stings also come 

with the risk of serious allergic reactions (Lecture 23). 

biofeedback

: Biofeedback is a technique of using monitoring of biological 

functions, such as heart rate or electrical brain activity, in order to achieve a 
state of maximal relaxation. This can be a useful technique, but there is no 
evidence for medical bene

¿

 ts beyond that of relaxation (Lecture 19). 

blood type diet

: Blood type refers to various protein antigens that are found on 

blood cells and that are reactive to the immune system. The most commonly 
known (but not only) system is the A-B-O blood type. Individuals will make 

94

Glossary

antibodies against whatever antigen they do not possess themselves, so those 
with blood type B will make antibodies against type A. Therefore blood 
typing is essential for matching blood donors, or for any organ transplant. 

However, there is no theoretical reason or evidence to suggest that blood type 
has any other biological signi

¿

 cance. There are popular claims that different 

blood types require different dietary needs for optimal health, but this is not 
based on any science or evidence (Lecture 23). 

bottled water

: Bottled water has become a popular product, and many 

people purchase bottled water for the convenience. However, bottled water 
varies in quality as much as tap water, and there is no consistent advantage to 
taste, purity, or healthfulness to bottled water over tap water (Lecture 2).

brain death

: Brain death is de

¿

 ned as a complete lack of brain activity, 

which must be documented to strict criteria either by neurological exam, 
electroencephalography, or other diagnostic testing. In many states and 
countries brain death meets the legal de

¿

 nition of death (Lecture 20). 

brain usage

: Anatomical and functional studies show that humans use their 

entire brains. Despite the popular myth, we do not use only 10% of our 
brains and, in fact, it is not possible to be conscious using just 10% of the 
brain. The source of this myth is not clear, but it is not based on any scienti

¿

 c 

belief or evidence (Lecture 20). 

caduceus

: The winged staff of Hermes (with two snakes) is not the of

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 cial 

symbol of medicine. This was a simple mistake made by the US Army 
Medical Corp in the late 19

th

 century and was then perpetuated. The Staff 

of Asclepius (with one snake) is the actual symbol preferred by medical 
professionals and now recognized by the AMA (Lecture 23). 

caffeine

: Caffeine is a widely consumed drug with multiple biological 

effects. It acts as a mild diuretic, but you can still rehydrate with 

À

 uids that 

contain caffeine. Regular caffeine drinkers become tolerant to the diuretic 
effect (Lecture 2). While caffeine is a stimulant and can interfere with sleep, 
its use has not been linked to hyperactivity (Lecture 7).

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calories

: A calorie is a standard measure of energy. The term “Calorie” 

(sometimes designated with a capital “C”) is also used to refer to a kilocalorie 
of energy in food (so 1 food Calorie = 1000 calories of energy). And 3500 
Calories translates to one pound of fat, which is the body’s way of storing 
energy. Weight control is about the proper balance of total calories consumed 
versus total calories expended. Overeating by 50 calories per day can mean 
gaining 5 pounds per year. It does not matter when you eat the calories; late-
night eating does not necessarily affect weight (though it can cause problems 
with re

À

 ux; Lecture 4).

cancer prevention

: Cancer is not one disease but a category of diseases (also 

called neoplasms). Therefore there are different methods for preventing and 
treating different kinds of cancer. Cancer prevention is largely accomplished 
through lifestyle choices, such as avoiding smoking. The relationship 
between diet and risk of cancer is complex and still the focus of ongoing 
research, but in general a diet rich in fruits and vegetables may be of bene

¿

 t 

(Lecture 23). 

cell phones

:

Cell phones are a source of nonionizing radiation. This has 

caused some popular concern about their potential health risks. However, 
nonionizing radiation (electromagnetic radiation of near-ultraviolet or longer 
wavelength) is too low energy to break chemical bonds, and therefore cause 
any direct damage to DNA or other cell molecules (Lecture 18). 

chewing gum

: Chewing gum is made of indigestible gum resin, but 

normally passes through the gastrointestinal tract without getting stuck. Not 
recommended for children under 5 years due to choking hazard (Lecture 1).

chiropractic

: Chiropractic is a system of practice originating with D. 

D. Palmer in 1890s based on notions of life energy. Some chiropractic 
continues to follow Palmer’s unscienti

¿

 c ideas, while others more closely 

resemble contemporary physical therapy and sports medicine (Lecture 18). 
Chiropractic generally continues to focus on manipulation of the back to 
affect the alignment of the vertebra. Chiropractic remains controversial due 
to the lack of a scienti

¿

 c basis for many of its practices. 

96

Glossary

cholesterol

: Cholesterol is a waxy steroid-like molecule used as a structural 

component in living cells. It is also a building block of other important 
substances, and is essential for life. It is transported in various forms in the 
blood and can build up on the inside of blood vessel walls, eventually leading 
to plaques and blockages. To minimize cholesterol buildup, it is optimal to 
keep total cholesterol levels relatively low and to maintain a relatively high 
ratio of HDL (so-called good cholesterol derived from plants) to LDL (so-
called bad cholesterol derived from animal fat; Lecture 4). 

See also

fats

.

chronic fatigue syndrome

: This is a controversial disorder characterized by 

a state of chronic fatigue without any identi

¿

 able causes. In a minority of 

patients with chronic fatigue a chronic infection with the Ebstein-Barr virus 
(EBV) has been identi

¿

 ed and is considered a plausible cause. However, 

many people without chronic fatigue are EBV positive, and many people 
with chronic fatigue are EBV negative. Therefore there may be other 
unrecognized causes. In addition, patients with chronic fatigue may simply 
have a known but currently undiagnosed condition to explain their fatigue 
(Lecture 13). 

chronic Lyme disease

: The term “chronic Lyme” can refer to chronic 

symptoms following an acute infection with the bacterial spirochete 

Borrelia 

burgdorferi

. However, there are patients and practitioners who believe that it 

is possible to have a chronic active infection with 

B. burgdorferi

 that survives 

even thorough antibiotic treatment. This claim remains controversial and 
without empirical evidence (Lecture 13). 

coma

: Coma is a term used to de

¿

 ne a disorder of consciousness caused 

by damage to or physiological impairment of the brain. For nonreversible 
causes of coma, patients rarely “wake up” without neurological impairments. 
Conscious processing (seeing/hearing) is unlikely in persistent vegetative 
state (PVS) but may occur in a minimally conscious state (MCS)—although 
currently there is little difference in prognosis between PVS and MCS 
(Lecture 20).

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common cold

: The common cold is an upper respiratory infection caused 

by many different viruses. Cold weather does not cause colds; it is possible 
to catch a cold in the summer. Vitamin C, Echinacea, and supplements like 
Airborne will not prevent or treat a cold. There is nothing special about 
chicken soup, although hot liquids may provide some symptom relief 
(Lecture 9).

copper

: Copper is a nonferromagnetic base metal (it cannot contain a 

magnetic 

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 eld). There is no evidence of bene

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 ts for pain or other indications 

from copper jewelry (Lecture 18).

dehydration

: Dehydration de

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 nes a relative lack of water in the body. Most 

people in most situations can maintain proper hydration simply by drinking 
when thirsty. Drinks with caffeine do not worsen dehydration (Lecture 2). 
In extremely hot or dry environments, at high altitudes, and with extreme 
physical exertion special effort may be required to stay hydrated. Looking at 
the color of your urine is one way to quickly assess your level of hydration. 

See also

water

. 

detoxing

: The human body’s inherent ability to remove toxins is often 

suf

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 cient (kidneys, skin, and breath). Drinking lots of water does not 

“

À

 ush out” the system. Although this is a common claim, there are no 

diets or supplements which have been shown to aid dotoxifying the body 
(Lecture 16). 

diabetes mellitus (DM)

: Diabetes mellitus is a group of disorders of 

glucose metabolism. Adult onset DM is often due to a combination of 
genetic predisposition and being overweight or obese. Diet is also important, 
speci

¿

 cally avoiding foods with a high glycemic index (GI), meaning that 

they are rapidly converted into glucose (Lecture 4).

dieting

: Special diets are sometimes required for speci

¿

 c health conditions, 

like diabetes and heart disease. However, for weight control and overall 
health it is recommended to adopt healthy eating habits and lifestyle for life, 
rather than going on a restrictive or crash fad diet. Fasting is also of no long-
term bene

¿

 t. Diet pills do not aid in long-term weight control and may be 

harmful (Lecture 4). 

See also

calories.