SARS Protection – More than a
Face Mask
Total Immune System Enhancement
Could SARS eventually be deadlier
than the Spanish flu epidemic of 1919 that killed more than 50 million
people?
Could the higher rate of death for
victims of SARS in Western countries be due to their high-fat, meat- and
dairy-based diet? 1
SARS, or severe acute respiratory syndrome,
which is caused by a virus, is making headlines worldwide – so you have
most likely thought about how you might avoid becoming a victim. A new
Gallup poll reports that 43 percent of Americans are now worried about the
disease. Nearly a half a million web sites have been generated, selling
protection – from face masks and disinfectants to nutrients. As of the
end of June, 8000 cases in 27 countries with 800 deaths have been
reported. (I realize these seem like paltry numbers when it comes to
dietary diseases like diabetes, heart attacks, strokes, and cancer, but it
has the potential to become a very big cause of death and suffering.)
Many health authorities are declaring victory over this virus – but don’t
be so sure. The future may be much bleaker than these optimistic and
unsupported predictions, especially with the winter months of high
infectivity approaching soon.
Some people fear the SARS virus could
become a worse epidemic than the Spanish flu of nearly a century ago.
Right now the SARS problem does not seem like such a serious threat, but
microbes often adapt and change behavior in the process of spreading.
After an initial wave of spreading across the world, the Spanish flu virus
became 10 times more virulent during its second swell. There are some
interesting comparisons between the viruses:
-
Both may have originated in China
-
Both began as diseases in animals and
through mutation gained access to humans
-
Both are systemic illnesses, but involve
primarily the respiratory system
-
Both are spread by coughing and close,
casual, contact
-
Both spread more viciously during the winter
months
-
Malnourished (who are often the poor) fare
worse in both viral infections
-
SARS is deadlier, killing 10% to 15% of
victims, compared to 3% for the Spanish flu
-
No effective medications are available for
either virus
-
Quarantine is of very limited effectiveness
– both are highly contagious before symptoms appear, and one person can
spread the virus to many other people
Right now, not traveling to hot spots, like
Asia or Toronto, Canada, seems to be very effective prevention, but very
soon that strategy may not have value if the virus spreads into your
neighborhood. Wearing a face mask, gloves, and washing your hands are
also very superficial approaches for protecting you and your family – and
the fact that the virus lives on surfaces for several days will make it
necessary to maintain this barrier-type protection all of the time and to
strictly avoid cross-contamination. Modern drug approaches have failed –
the combination treatment of antibiotics, antiviral agents (Ribavirin) and
steroids is essentially useless.
Of great interest is the fact that the
death rate in Toronto is twice as high as the overall death rate, which
reflects figures mostly from China (12.7% vs. 6.4%).1 Even
with all the medical technology, hospitals, and drugs in Canada compared
to China, people in Toronto are much worse off. Does this mean the
Chinese are healthier people, with stronger immune systems? I think so.
The main difference between these two populations is their diet – the
Chinese are living on a higher carbohydrate (rice), higher vegetable,
lower-fat, lower-meat, lower-dairy diet than the people in Toronto. The
diet of Westerners inhibits their immune system.
The newest figures predict 15 percent of
the victims of this disease will die. Death rates vary by age: 6% among
those 25 to 44; 15% in those 45 to 64; and 50% for people 65 and older.
Obviously not everyone exposed catches this virus, and even fewer of those
infected die from SARS. Therefore, you want to do everything possible to
be among the stronger people who resist becoming infected, or as a second
choice, who survive. Your best chances to accomplish these goals are with
your own innate strengths – by bolstering your immune system into a
disease-fighting machine.
A healthy immune system works in an
orchestrated way with many players defending the body against foreign
invaders, like the SARS virus (a coronavirus). Our skin and mucosal
membranes provide a physical barrier. In addition to acting simply as a
barrier, these surfaces mount an inflammatory reaction against the
invaders. Unfortunately, this virus sometimes penetrates surfaces like
the membranes of the eyes, nose, mouth, intestine, and airways (lungs).
Once the intruders are inside the body, cells that eat the invaders,
called phagocytes, come into action. Other cells, called lymphocytes and
natural killer cells make antibodies and other substances that deactivate
and kill the virus. Your immune system will mount and sustain for weeks
the battle for your life – until won or lost. Right now you can make some
decisions and changes that will favor winning.
The Young and the Elderly
People living at both ends of life – babies
and seniors – are most susceptible to infections of all kinds and worse
outcomes. Exclusive breast-feeding for 6 months, followed by continued
breast milk until 2 years of age with the addition of starches, fruits and
vegetables is the best protection for infants. (No vaccines are yet
available for SARS.) When mother is exposed to an infection her immune
system makes antibodies and other anti-infective substances (IgA,
lactoferrin, or lysozyme) that are transferred through her milk directly
into the baby – whose intestine at this stage of life is permeable and
able to absorb all of these disease fighters.2
As we age, the strength of our immune
system declines, resulting in an increase in incidence of infections,
cancer, and other diseases. To make matters worse, nutritional
deficiencies that affect their immunologic vigor are found in one-third of
the elderly in industrialized countries. Those at especially high risk of
poor nutrition are the very old, poor and/or isolated persons. Better
nutrition for these people is no different than for people of other ages –
they need a diet based on starches with the addition of fruits and
vegetables. However, in this age group, people with diabetes, and in
persons in developing countries – all groups vulnerable to nutritional
deficiencies – studies have shown improvement in their immunity with
addition of vitamin and mineral supplements.3,4
In otherwise nutritionally adequate people, supplementation is at best a
waste of money and effort, and at worst harmful.
Good Nutrition and Lifestyle is the Key
to Effective Immunity
With a severe deficiency of food (calories)
– starvation – the entire immune system can become compromised and this
can lay the way for infection of the body by a great variety of
microorganisms. This means an overall deficiency of calories, protein,
fats and all the other life-giving nutrients we gain from our foods.
Isolated deficiencies of micronutrients are rare, except for iron, vitamin
A, and zinc.
At the other end of the spectrum is the
overnutrition that is so prevalent in Western societies, with as many as
65% of people being too over-fat for their own health. This form of
malnutrition also sets people up for infections and a poorer chance of
survival once they’re sick. Obesity has been shown to diminish the immune
response.5 The data on weight loss improving immune response
is, however, plagued with mixed results – and I believe this is because
there are many ways to lose weight and some are very unhealthy, like high
protein diets.
The best way to lose weight and
improve the immune system is to eat a low-fat, plant-based diet.
A Plant-Based Diet Improves Immune
Response
A recent study of ten middle-aged and
elderly people with the slightly elevated cholesterol levels typical of
many Americans showed a change to a low-fat diet (15% of calories) (not
vegan) boosted their immune system.6 Reasons for this
improvement are because these people lost weight, reduced their
cholesterol levels,7 added vegetables and removed much of the
immune system-suppressing fat from their diet.
Fats, Including Olive and Omega-3 Fats,
Suppress the Immune System
All fats, and especially the “good” fats,
suppress the immune system.8 This means all the added fat,
not just animal fat, must go. Olive oil,9 corn oil,10 and the omega-3 fats, like flaxseed oil11 and fish oil,11-13 must be removed to enhance immune function.
You know these so called “good” omega-3
fats suppress the immune system. They are recommended to reduce the
inflammation of arthritis and they work by causing a generalized
suppression of the immune system. This means that the immune system that
fights off viruses, and suppresses cancer growth, is also depressed.
Fish Decreases Immune Function Too
You also need to remove the fish because of
their anti-immune system effects. A study of 22 subjects over 40 years of
age fed a low-fat, high-fish diet was found to significantly decrease
various parameters of the immune response; in contrast to this diet when
it was low in fish.14 The authors concluded concerning fish
consumption, “Such alterations may be beneficial for the prevention and
treatment of atherosclerotic and inflammatory diseases, but may be
detrimental with regard to host defense against invading pathogens.”
Low-Calorie, High-Protein Diets Harm
Immunity
Even though obesity is associated with poor
immune system function, do not try to repair the damage with a
low-calorie, high-protein diet. Twelve nondiabetic obese subjects were
studied during a 6-week period of following a 400 calorie liquid protein
diet. Significant decreases were observed in immune cells (total
leukocytes, neutrophils, lymphocytes, and monocytes).15 The
authors wrote, “…the results of this study clearly justify some caution
in the long-term use of these diets.”
There are other positive lifestyle
steps you can take to bolster your immune system.
Coffee Suppresses Immunity, But Tea
Benefits
Starbucks is going to be unhappy about this
finding. The effect of coffee consumption on the immune system, studied
in 15 men and women, showed that functions of immunity were about
one-third lower during a period of coffee drinking compared to a period of
abstinence from coffee.16
However, tea is a great stimulant
beverage. Eleven healthy non-tea-drinking people were instructed to drink
a tea made with one bag steeped for 5 minutes in 100 ml of boiling water.17
They were compared with 10 people instructed to drink 5 to 6 cups of
instant coffee. The tea, but not the coffee, caused the immune cells to
become more effective at defending the body. This effect was believed to
be due to substances (alkylamine antigens) found in tea and plants that
mimic the effects of protein found in microorganisms – and in this way
they stimulate the immune system into action.
Alcohol Overuse is Detrimental
While malnutrition, vitamin deficiencies
and advanced liver disease can compromise your immune system; alcohol
itself is toxic to the system. Chronic and even acute, moderate alcohol
use can increase your susceptibility to infections.18 But
moderation (too often defined in the eyes of the user) may not be so bad.
There is some evidence that daily consumption of small amounts (one to two
6-oz glasses) may be beneficial for immune function.19
Too Much Sunshine Can Be Hazardous
Researchers calculated that approximately
100 minutes of solar exposure at around noon in mid-latitudes (Italy,
Spain, Northern California, Pennsylvania) would suppress the resistance to
infections by microbes (L. monocytogenes) in the most sensitive humans.20 Some sunlight is essential, preventing vitamin D deficiency diseases,
such as rickets. Over 90% of our vitamin D comes from sunlight exposure.
The amount needed is very small. For example, for a person with a
moderately fair complexion, five minutes at noon, two to three times a
week, of sun exposure on the face, hands and arms (6% to 10% of the body)
in Boston in the spring, summer and fall is thought to be sufficient.
However, the amount of exposure varies with the skin pigmentation,
latitude, and atmospheric conditions. A six-fold increase for very black
skinned people may be required for vitamin D synthesis.
The SPF rating of a sunscreen does not
necessarily indicate whether it will protect from immune suppression. The
wavelengths that burn are different than those that suppress. The best
protection seems to be with those sunscreens that filter both UVB and UVA;
and have a relatively high SPF value.21 You should also
employ strategies of sun avoidance whenever possible, like wearing hats
and other protective clothing and/or sunglasses.
Sleep Can Depress More than the Immune
System
Sleep is believed to have a restorative
function on the immune system – and prolonged sleep deprivation may
suppress the immune system.22 However, one night’s sleep loss
has actually been shown to increase the activity of the immune system.23 Therefore, short term sleep deprivation is not harmful to the immune
function, but prolonged sleep deprivation may increase susceptibility to
viral infections.
However, there is a balance between
too much and too little sleep. Too much sleep is known to cause mental
depression24 and this may lead to worse health and increased
risk of infection.25 Limiting the hours of sleep is an extremely powerful treatment for
depression.24 Most healthy adults need 5 to 7 ½ hours a night.
Pregnant women, children and people who are ill need more sleep.
Strenuous Exercise Increases Your Risk of
Infection
Moderate levels of exercise seem to improve
the immune function, especially for the elderly.26 Unfortunately, intense exercise can severely depress the immune system and
increase the risk of infection. High intensity, prolonged bouts of
exercise have been shown to increase the susceptibility to upper
respiratory infections, and during the incubation period of an infection,
exercise may worsen the disease outcome. Researchers monitored levels of
infection in more than 200 runners and rowers. They found the levels of
infection were lowest in middle-distance runners, and highest in runners
after a full or ultra-marathon and in elite rowers after intensive
training.27,28
The Choices You Make Now May Keep SARS Away
Tomorrow
Therefore, you do not have to sit idly
waiting for SARS to happen to you. You can make real choices right now
that will make real differences in your future. It is especially
convenient that these choices for your immune system are the same ones you
are making to prevent other potential future health tragedies, like heart
disease and breast cancer – and they are cost-free, non-toxic, and
side-effect-free. So you have no reason to delay.
References:
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in prevention of neonatal infection.
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4;138(5):365-71
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