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The Non-Medicated Life:
Vitamins and Supplements for Heart Health (Part
Two)
Editor's Note: This is the 6th in a series
on optimal diet and lifestyle to help prevent and treat heart disease.
Any planned change in diet, exercise or treatment should be discussed
with and approved by your personal physician before implementation.
The help of a registered dietitian in the implementation of dietary
changes is strongly recommended.
Medicines are a mainstay of American life and
the healthcare system not only because they are perceived to work
by the individual taking them, but also because they can be shown
to work by the objective assessment of scientific study. The most
helpful medications have been proven in clinical research trials
to affect some of the most important clinical outcomes. Clinical
trials, for example, have shown that some of the medicines of western
science may reduce heart attacks, strokes, and cardiovascular death.
As has been shown in the first five installments of The Non-Medicated
Life, informed diet and lifestyle may accomplish, naturally, for
the majority of individuals, many, if not most, of the benefits
of medications. As part of this dietary and lifestyle approach,
certain dietary supplements have been shown by rigorous scientific
scrutiny to help protect the heart, while for others there is some
preliminary data; finally, for some there is no reliable data to
recommend use.
Of the dietary supplements for heart health,
omega-3 fish oil has the most compelling data to support its use.
As is frequently the case in medicine, epidemiological or population-based
data helped direct researchers to investigate fish oil. It was observed
that Inuit peoples (Eskimos) had both very low rates of coronary
artery disease and a higher than normal consumption of fat. As compared
to western diets, however, the fat was high in omega-3 fatty acids
EPA (ecosapentaenoic acid) and DHA (docosahexaenoic acid). Clinical
trials were designed to investigate the effect of fish oil on individuals
at the highest risk for heart attack - those who had already suffered
their first attack. The Diet and Reinfarction Trial (DART) and the
Gissi Prevention Study showed marked benefit. DART showed a 29 percent
lower death rate from fatal heart attacks in those consuming 500
milligrams per day of fish oil consumed as fish; Gissi showed a
45 percent reduction in sudden cardiac death in those consuming
850 milligrams per day of fish oil from capsules.
On the basis of these and other clinical trials,
the American Heart Association recommends the consumption of 2 fatty
fish meals a week for everyone and if one has heart disease the
consumption of 1 gram per day of omega-3 fish oil either from fish
or supplements. The fish highest in omega-3 (salmon, mackerel, anchovies,
sardines, herring or the acronym S.M.A.S.H.) will generally have
between 1.0 and 1.8 grams of omega-3 fish oil in a 4-ounce portion.
Other types of fish may have as low as 0.1 grams, so the type of
fish chosen is important to the decision to use supplements.
An additional consideration is how the fish
was raised. Farm-raised fish may have one-third less omega-3 than
ocean-harvested fish of the same type. Moreover, farm-raised fish
are fed fish feed of variable purity. Some farm-raised fish will
have higher levels of polychlorinated bi-phenyls (PCBs) or dioxin,
contaminants which may have serious adverse health consequences
and should be avoided. As long as the consumer is not told the gram
quantity of omega-3 in a 4-ounce portion of farm-raised fish, nor
the results of an independent lab assessment of the amount of PCBs
and dioxin present as compared to wild fish of the same type, it
is prudent to minimize or avoid consuming such fish. Canned or frozen
ocean-harvested fatty fish available year round or seasonal, fresh
ocean-harvested fatty fish is best.
Omega-3 fish
oil and plant-based omega-3 fatty acid has been
rigorously shown to be heart protective and to reduce clinical events.
As an alternative, fish oil supplements provide
established amounts of omega-3s and have been tested by independent
labs for the presence of PCBs and dioxin. Such supplements are generally
as free of contaminants as if one were getting the same amount of
fish oil from wild ocean-harvested fish (see Consumer Reports, July
2003). Finally, the consumption of certain ocean-raised fish such
as king mackerel, swordfish and to some degree tuna that tend to
be larger and concentrate mercury in their bodies should also be
minimized or avoided. Children, pregnant women as well as nursing
mothers and women trying to conceive should avoid consuming such
fish and should check with their physician for specific recommendations.
Recent data would also suggest mercury may damage the heart, so
those using omega-3 fatty acids for heart protection may want to
consider supplements for this reason as well.
Finally, apart from reducing the risk of cardiovascular
sudden death, fish oil supplements used under a physician's care
may reduce blood triglycerides by 30-50 percent. The dose of fish
oil used for this purpose is much higher, in the range of 6-9 grams
per day. In those with elevations of both the bad cholesterol (LDL)
and triglycerides, fish oil may be combined with statin drugs to
reduce the dose of the statin or avoid the addition of a second
medication.
Flax seed oil is another supplement that has
some data to support its use, but the data is less conclusive than
for fish oil. Flax seed oil is 50 percent alpha-linolenic fatty
acid, a plant-based omega-3 fat. Alpha-linolenic fatty acid is not
synthesized in the body and thus must be supplied in the diet and
most interestingly is converted by the body to EPA and DHA or fish
oil. The conversion, however, is not efficient and only 15-30 percent
of alpha-linolenic fatty acid is converted to fish oil. In the presence
of omega-6 polyunsaturated fats, saturated fat and trans-fat the
conversion is markedly reduced.
Nevertheless, there is clinical trial data to
support the heart benefit of such plant based omega-3 fats. The
Lyon Diet Heart Study (see The Non-Medicated Life, October 2003)
showed that those consuming a high alpha-linolenic fatty acid Mediterranean
diet had a 70 percent reduction in cardiovascular deaths and non-fatal
heart attacks as compared to those eating a prudent western diet.
In this clinical trial, the higher level of alpha-linolenic fatty
acid was achieved by the consumption of canola oil margarine as
a supplement to a base of olive oil. Other sources of alpha-linolenic
fatty acid include ground flax seed, walnuts, almonds and a vegetable
called purslane. Those interested in increasing their alpha-linolenic
fatty acids from nuts should discuss this first with their physician
as the presence of diverticulosis of the bowel may predispose those
eating nuts to diverticulitis, a potentially life-threatening infection
of the bowel wall. Those choosing instead to consume flax seed oil
as a supplement should do so in capsules rather than from a bottle.
Flax seed oil oxidizes and degrades quickly after a bottle is open
and the potential benefit may be lost.
Although not supported by clinical trial data
soy protein, psyllium husk (Metamucil) and plant sterol esters are
recommended by the National Cholesterol Education Program to reduce
the risk of cardiovascular disease on the basis of their proven
ability to reduce LDL, a measurable marker of heart disease risk.
To this end, soy protein should be consumed in the amount of 25
grams per day usually as a protein drink. Soy protein may reduce
LDL by up to 5 percent. Psyllium husk may be taken as a rounded
teaspoon in 8 ounces of water up to three times a day with a meal.
Psyllium husk capsules are a more convenient alternative and one
would work up to 5 capsules with 8 ounces of water three times a
day with meals. Psyllium husk may reduce LDL up to 5 percent. Plant
sterol esters in margarines such as Take Control and Benecol taken
in the amount of 2 grams per day may reduce LDL 7-14 percent. Plant
stanol capsules may be less effective, if not consumed with sufficient
fat. Finally, other products have no clinical trial data at present
to support their use and no marker of heart disease risk that they
reduce. Coenzyme Q-10 a much talked about supplement which has some
data supporting its consideration in heart failure patients has
no clear data to date for preventing or treating coronary artery
disease.
In summary, the consumption of omega-3 fish
oil and to a lesser degree plant-based omega-3 fatty acid has been
rigorously shown in clinical trials to be heart protective and to
reduce clinical events. Soy protein, psyllium husk, and plant sterol
esters have been shown in clinical trials to reduce cholesterol
markers of disease risk. The use of such evidenced based supplements
for heart health may augment a more natural approach including diet
and lifestyle and thus reduce an over reliance on the proverbial
bottle of pills to solve all of an individual's health care problems.
Center for Preventive Medicine
& Cardiovascular Health
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at
Mid-Valley Cardiology
111 Mary's Ave. Suite 3
Kingston, NY
845-339-3663
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Main Office
400 Patroon Creek Blvd.
Albany, NY
518-618-1100
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at Glens Falls Associates in Cardiology
747 Upper Glen St.
Queensbury, NY
518-793-1083
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