Confessions of a Fish Killer
I fell in love
with the ocean at age 5 (in 1952) after watching a film in my
kindergarten class about undersea life: fish, corals, giant
clams, and hermit crabs. When I was 12, I became a SCUBA diver,
but my underwater explorations were limited to the murky waters
of Michigan lakes. During my early teens, our family vacations
were to the Outer Banks of North Carolina, where we always
included some deep sea fishing—catching and eating flounders,
blues, and Dorado. My first ocean SCUBA diving experience at age
18 was at John Pennekamp National Underwater Park in the Florida
Keys—here thousands of colorful fish swam through a forest of
corals. I enjoyed this experience so much that Mary and I
returned to the Keys and more diving for our honeymoon in 1972.
That same year we moved to Hawaii. Here we collected small
tropical fish for our saltwater aquariums from the shallow
waters surrounding Oahu. Unfortunately, within a few days of
being removed from their natural environment, most of them we
found floating belly-up.
For the first
time I realized I was living with a grim conflict: I was a fish
lover and a fish killer. Once or twice a year for the next two
decades, I captured large edible fish like mahi-mahi, tuna, and
salmon with lines and spears in Hawaii and California. I
considered it my right to eat them. The constant drone about
their health benefits from doctors and dietitians helped me
justify my slaughter of these amazing animals.
have changed over my sixty-year lifetime. Ninety percent of the
large fish—the ones that make baby fish—are gone. Thirty-eight
percent of all animal sea life, including bluefin tuna, Atlantic
cod, Alaskan king crab, and Pacific salmon have had their
populations cut by more than 90%, and seven percent of the fish
species have become extinct.1 Because of the rarity
of blue fin tuna, the Japanese are now making some of their
sushi with beef. The price of fresh wild salmon has increased
to $11 a pound, when it’s available, which is only a few times a
year. Fishing industries have collapsed worldwide and many of
coral reefs are now bleached and barren. Reliable predictions
warn that by the middle of this century (2048) all fish and
seafood species will have collapsed—they will be extinct or on
the verge of extinction.1
demand for fish as food has been the major reason for the
devastation of the oceans and part of that demand comes from the
belief that fish-eating is essential for good health. This is
not correct—in fact, in our polluted world, eating fish has
become a well-established health hazard.
I Hated Fish Fridays
I grew up in
the suburbs of Detroit, Michigan, in a neighborhood that was
predominately Catholic. That meant every Friday fish was served
for dinner. No matter how much it was breaded, salted,
seasoned, and/or fried to disguise the taste; come dinner time,
I dreaded Fridays.
When consumers have a choice—like they do at every fast food
restaurant—between beef and chicken or fish—what do they choose?
Considering fish’s relative unpopularity, I would say most
people don’t like the taste of fish.
“fishy” connotes a message
quite unpleasant-smelling sulphurous aroma that resembles fresh
fish. Anchovies are synonymous with bad taste—unless you like
The taste of
the flesh of a fish depends to a large extent upon that fish’s
diet. Many of the most popular fish; tuna, swordfish, salmon,
and rockfish, are carnivores, feeding off small
unpleasant-tasting sea animals, like anchovies, herring, and
squid. But people have the ability to adapt their taste buds
and learn to like almost anything, even the repugnant odor of
Sulfur compounds are another
reason for fish’s lack of gustatory appeal. Rotten eggs and
spoiled fish are malodors because of the hydrogen sulfide gas
that is released by bacterial actions. Sulfur also taints many
well waters. Foul body odors (halitosis, and smelly flatus and
perspiration) are primarily the result of sulfur compounds—the
origin of this sulfur is our diet in the form of
sulfur-containing amino acids, like methionine. The sulfur
content of fish is particularly high, for example salmon has 12
times more methionine than do sweet potatoes.
make fish- and seafood-eating more tolerable. Most people
swallow these sea animals only after they are blackened on a
barbecue, smothered with cocktail sauce, or blended with bisque.
The Health Claims Are Fishy
“Fishy,” apart from meaning “like a
fish,” also means:
Not as expected,
inspiring doubt or suspicion, dubious, questionable,
suspect, suspicious, shady, funny, odd, implausible,
unlikely, not honest, and not legitimate.
Consumers are taught fish are
their only reliable sources of essential omega-3 fatty acids,
called eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA),
and therefore they believe that by avoiding fish they would
suffer serious malnutrition. Sellers of fish oil supplements go
so far as to warn, “Supplementation with fish oils that are rich
in EPA and DHA is necessary to ensure you are receiving adequate
amounts of these nutritionally important fatty acids.”
organizations worldwide, including the American Heart
Association, the American Medical Association, the American
Diabetic Association, the British Dietetic Association, and
Australia’s leading health research body, the National Health
and Medical Research Council (NHMRC) (to name a few) also
recommend that people eat fish, primarily for the omega-3 fats.
These same groups also warn of the hazards of methylmercury and
other environmental contaminants in the fish—appearing balanced.
Recommendations to eat fish are
based on laboratory research, but originate primarily from
observations of various populations of people worldwide. For
example, the rate of heart disease among fish-eating
populations, such as the Japanese, is very low, and this has
been attributed to the so-called “good fats” they receive from
eating fish. Researchers overlook the marked differences
between overall Western and Japanese diets. The primary
ingredient in the Japanese diet is rice and this is the reason
they enjoy better health, are trimmer, and more active. The
small amount of fish eaten daily is incidental.
But the “fish is health food”
theory flourishes because, for many people this is the easy
road—simply add a serving or two of fatty fish to their weekly
diet—rather than giving up the real causes of heart disease.
Don’t think I overlooked the positive consequences of adding
fish a couple of times a week—it does replace some of roast
beef, pork, cheese, and chicken that would have otherwise been
Good Fats Are from Plants
The possibility of brain damage, especially to
the unborn or young children, strokes the emotional cords of our
hearts.2 A number of writers claim that only a diet
based on seafoods can provide the necessary quantity of
essential fat (docosahexaenoic acid) to support the human brain
and that a switch to such a diet early in human evolution was
critical to human brain evolution.2,3 However, a
critical review of this claim by John Langdon of the departments
of Biology and Anthropology of the University of Indianapolis
came to this conclusion, “There is no evidence that human diets
based on terrestrial food chains with traditional nursing
practices fail to provide adequate levels of DHA or other n-3
fatty acids. Consequently, the hypothesis that DHA has been a
limiting resource in human brain evolution must be considered to
Only plants can make the omega-3
fats—fish don’t; nor do cows or people. Alpha linolenic acid
(ALA) is made by plants and converted into DHA by infants and
adults in sufficient amounts to supply all of our needs
including those for brain function and development. After all,
the African elephant with a brain volume of 3000 to 4000 cm3,
compared to the human brain of 1400 cm3, has no
trouble making all the essential fats its brain, and the rest of
its huge body, needs from plant foods.3 You can
safely assume a comparatively puny human being can do the same.
Do Fish Have a Metallic Taste? Or Has My
Fish-eating Caused Me Brain Damage?
discussing healthy brain development and fish, let’s not forget
mercury. It may be all in my mind, but I swear the last tuna I
ate had a metallic taste. Mercury is a natural element found in
the earth, and is released as industrial pollution during
various manufacturing processes. Much of this metallic
substance accumulates in the rivers, streams and oceans, and is
converted in the environment into a highly toxic form called
methylmercury. In this organic form mercury becomes
concentrated in the food chain by processes referred to as
bioaccumulation. Fish, especially those predatory species high
on the food chain, like, fresh water pike, walleye and bass, and
salt-water tuna, swordfish, and mackerel, become heavily
contaminated with mercury. The consumption of
mercury-contaminated fish is the main exposure for people.
Almost all of the mercury consumed is efficiently absorbed by
the intestinal tract. Since our bodies have no way of excreting
this toxin, mercury continues to accumulate throughout life,
exerting its detrimental effects. Serious health risks include
damage to the nervous system, heart, kidneys and immune
system—particularly for young children and the developing fetus.
The results of
mercury poisoning for the brain are motor dysfunction, memory
loss, and learning disabilities; as well as depression-like
behaviour.4 The Food and Drug Administration (FDA)
and the Environmental Protection Agency (EPA) are advising women
who may become pregnant, pregnant women, nursing mothers, and
young children to avoid some types of fish, and eat fish and
shellfish that are lower in mercury.5 Other
toxic compounds, such as fat soluble dioxins, and
polychlorinated biphenyls, are also found in fish and fish oils.6
Fish-Eating Does Not Decrease Heart Disease
Eating fish may be healthier for
the heart for people in Western countries simply because it
replaces some of the saturated fats that would otherwise be
found in the livestock on their dinner plates. A study
published in the May 2007 issue of the American Journal of
Cardiology came to this very conclusion and reported, “The
data supporting the inverse correlation of fish or omega-3 fatty
acid (eicosapentaenoic acid plus docosahexaenoic acid)
consumption and coronary heart disease are inconclusive and may
be confounded by other dietary and lifestyle factors.”7
The research published in our
major medical journals, which says, “Fish are bad for the
heart,” somehow fails to influence doctors, dietitians, and
health organizations who are telling us how to live
healthfully. Therefore, the public rarely hears about the
following dissenting research:
Two recent studies have shown that
people with the higher amounts of mercury in their bodies,
caused primarily by fish-eating, have more heart trouble. The
first one, published in the New England Journal of Medicine
in 2002, found that higher levels of mercury in toenail
clippings predicted a greater chance of future heart attacks.8
The next study looked at the mercury content of the hair and
found, “High content of mercury in hair may be a risk factor for
acute coronary events and CVD (coronary vascular disease), CHD
(coronary heart disease), and all-cause mortality in middle-aged
eastern Finnish men. Mercury may also attenuate the protective
effects of fish on cardiovascular health.”9 More
plainly, the authors of this study concluded the high mercury
content negated the so-called protective effects of the “good”
fish fats (like EPA and DHA) on the blood vessels and heart.
Those people with the higher amounts of mercury in their hair
(indicating more consumption of fish) also had higher total
cholesterol and LDL “bad” cholesterol levels, and higher rates
of hypertension and diabetes. Higher blood cholesterol levels
for fish-eaters should not be surprising since fish has twice
the amount of cholesterol as beef, chicken, and pork.
Cholesterol and Fish
of a total of 3114 men under 70 years of age with angina (chest
pain due to clogged heart arteries) who had been advised to eat
two portions of oily fish each week or to take three fish oil
capsules daily were found to have a higher risk of cardiac death
compared to men not given this advice.10
coronary heart disease documented by angiograms received either
fish oil capsules or olive oil capsules for an average duration
of 28 months.11 Fish oil lowered triglyceride levels
by 30%, but not these patients’ cholesterol. The amount of
closure (stenosis) increased by 2.4% and 2.6%, respectively. The
authors concluded, “Fish oil treatment for 2 years does not
promote major favorable changes in the diameter of
atherosclerotic coronary arteries."11
review of 48 randomized controlled trials involving
36,913 participants taking fish oils or eating oily fish, found
no health benefits from these “healthy fats,” and concluded,
“Long chain and shorter chain omega 3 fats do not have a clear
effect on total mortality, combined cardiovascular events, or
The Underlying Reasons Fish
Components May Cause Harm
fish, high in omega-3 fats, are felt to protect people from
heart disease is that this kind of fat “thins” the blood and
thereby helps prevent a blood clot (thrombus) from forming in a
heart artery and shutting off circulation to the heart muscle.
However, “good fat” from eating fish, thus causing “good
effects,” is only a small part of the story.
has been focused on the artery-damaging effects of the
environmental contaminant, mercury. Adverse effects of mercury
on blood vessels are from oxidative stress (free radical
formation), inflammation, thrombosis (blood clots), and muscle
dysfunction of the blood vessel walls.13 However,
mercury contamination is not the whole story, and even if
“clean” fish were available—and they are not—fish-eating would
still not be heart healthy.
There are many qualities of fish
which encourage heart disease. Fish are high in cholesterol
which elevates blood cholesterol.14 Even small doses
of fish oils have been shown to raise the “bad” LDL-cholesterol.15,16
Fish is also loaded with sulfur-containing amino acids (like
methionine) which raise homocysteine levels in the body.
Homocysteine is a well-accepted risk factor for heart disease
and feeding people methionine will cause dysfunction of their
arteries, which may promote blood vessel disease.17
(Remember, salmon has 12 times more methionine than sweet
potatoes.) Even fish oil alone can increase homocysteine levels.18
Consequences from Consuming Fish:
Fish cause a rise in blood cholesterol levels similar to
the rise caused by beef and pork.13
Their highly-acidic animal proteins accelerate calcium
loss,19 contributing to osteoporosis and kidney stones.
The addition of 5 ounces of skipjack tuna (34 grams of
animal protein) a day increases the loss of calcium from
the bones, into the urine, by 23%.20
dietary fiber or digestible carbohydrates are present in
fish—thus having a negative impact on bowel function and
endurance, like winning a foot race.
Although omega-3 fats “thin” the blood, preventing
thrombus formation (heart attacks); this same
anticoagulant activity can increase the risk of
bleeding complications from other sources, like a
hemorrhagic stroke or an auto accident.21
These good fats have antiinflammatory properties, which can
reducing arthritis pain, for example, as well as deleterious—causing
immune suppression, increasing the risk of cancer and
infection.22,23 Omega-3 fish fats have
been demonstrated to induce 10-fold more
metastases in number and 1000-fold in volume in an
animal model of colon cancer metastasis than does a low-fat
Fatty fish, commonly recommended salmon for example, is
half fat and loaded with calories, adding to one’s risk
for developing obesity and type-2 diabetes.
Omega-3 fats inhibit the action of insulin, thereby
increasing blood sugar levels and aggravating
Fish-eating prolongs gestation, increasing birth weight,
and the possibility of birth injury and increased
Fish Farming Is Not Guilt-free
The cost of fresh wild fish and
concern for the oceans has caused many consumers to buy farmed
fish—this may not be a wise decision. Farmed fish are loaded
with toxins because they are fed a diet of fish oils and fish
meal obtained from small pelagic fish which themselves contain
high levels of environmental chemicals. Farmed salmon, for
example, have higher contaminant loads than do wild caught
Because of the higher cost of
meals made with so-called good fats, farmed fish are fed rations
containing palm, linseed, rapeseed and other cheaper oils. The
ultimate fat composition of fish depends upon what they are
fed. Therefore, many farmed fish have a balance of fats that
would not be considered “heart healthy.”29
Other important issues that weigh
heavily on the fish farming businesses are the environment and
animal rights. Wastes from
fish cages, including fecal matter and uneaten food, along with
chemicals used in farming, such as pesticides, herbicides, and
antibiotics, are dumped into the oceans. When fish and other
organisms are kept in close proximity, they breed diseases. In
most cases farmed fish are carnivores, and their feed comes from
the ocean; for example, herring is used as salmon feed. Catching
herring depletes the food supply for the native fish, including
salmon, trout, tuna, grouper, and cod. And if you were
wondering, fish do have feelings too30—and life in a
fish farm must be like living in prison, on death row.
I Am No Longer Conflicted or Confused
I have lived
long enough to have witnessed the first-hand destruction of our
environment—it is real and now. I worry that in the very near
future when I want to take my grandchildren to see the wonders
of the ocean that I discovered in my youth, the sea life will be
gone. By correcting misinformation, the downward spiral
devastating our oceans can be reversed. The situation is not
hopeless, not yet.
I know the truth about human
nutritional needs. Therefore, I eat a diet of starches,
vegetables, and fruits and enjoy excellent health. Fish are not
health food. Every day I try to make choices that slow or
reverse the loss of our oceans; for example, I eat tofu tacos
(see the April 2006 McDougall newsletter)—they are far tastier
and healthier than fish tacos.
By being informed, and making
conscious choices, you can make a difference too.
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