Adirondack Sports March 2024

MARCH 2024 51
NON-MEDICATED LIFE
Medicines are a mainstay of
American life and the healthcare
system not only because they are
perceived to work by the individuals
taking them, but also because their
benefit may be shown by the objective
assessment of scientific study. Clinical
research trials have shown that some
of the medicines of Western science
may reduce the risk of Type 2 diabetes,
heart attacks, strokes, cardiovascular
death and even some cancers.
In the first 113 installments of the
Non-Medicated Life, a healthy diet and
lifestyle has been shown to accomplish
naturally for the majority of individuals
most of the benefits of medications in
the prevention of the chronic medical
conditions mentioned above. With
respect to a healthy diet, certain foods,
and food “components” may have a
disproportionate benefit. This is certainly
true for dietary fiber. However,
while optimal health may be compromised
by a lack of fiber, actual disease
processes may also result. Until recent
times humans ate as much as 100
grams of dietary fiber per day. Today
Americans may get as little as 10-15
grams a day. Why this is so, the benefits
of proper consumption, and the
consequences of underconsumption
of fiber are described below.
It is generally taken as established
fact that fiber is good for us. For example,
we are told it keeps our bowels regular.
Many folks with constipation have
learned through self-treatment of this
benefit. Consequently, we may search
out products either high fiber cereals,
or fiber supplements like psyllium. But
these are products. In reality, fiber is a
natural part of all plants. When we eat
plants – vegetables, fruits, and unprocessed
grain – we are eating fiber.
It is mostly in Western culture that
fiber is viewed as something separate
that must be added back, because in
some modern western cuisines, fiber
Benefits of Fiber
Revisited
By Paul E. Lemanski, MD, MS, FACP
Editor’s Note: This is the 114th in a
series on optimal diet and lifestyle to help
prevent and treat 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.
has, indeed, been removed. For example,
with respect to grains processing has
removed both the germ (fat) and fiber
(an innocent bystander of fat removal)
to avoid spoilage. While white flour may
have been initially developed to increase
shelf life, it has led to its increased incorporation
in many cuisines further removing
fiber from its natural place in the
human diet.
Likewise, modernity, with its de-emphasis
of hunting in favor of a process of
industrialization with animal husbandry
and slaughter has increased the availability
of beef, pork, and chicken. Humans
throughout our history have been omnivorous,
but the number of animals consumed
had been determined not only
by hunting prowess, but also by scarcity.
Animals have feet, plants do not. Although
animals are highly concentrated sources
of protein and fat, they are not always
as easily available for consumption as
plants. Consequently, human biochemistry
became adapted to the consumption
of large amounts of plants and their fiber,
vitamins and antioxidants.
The result of the reduction in the consumption
of plants in the modern Western
human diet – and the consequent reduction
in fiber, vitamins and antioxidants –
has been significant to human health in a
number of ways. I will outline below some
of the most important health benefits of
optimal fiber intake, the consequences of
insufficient fiber consumption, and suggest
strategies to address the shortfall.
Fiber may be classified as soluble (dissolvable
in water) fiber or insoluble fiber.
The former in sufficient amounts will
lower both blood glucose and LDL (the
bad) cholesterol primarily by interfering
with the absorption of glucose and dietary
cholesterol from the gut. Soluble fiber is
found in increased amounts in grains
such as oats, barely and psyllium, in fruits
such as apples and citrus fruits, and in
peas and beans. Insoluble fiber increases
stool bulk and may be found in increased
amounts in grains such as wheat bran and
whole wheat flour, nuts and beans, and
vegetables such as green beans, broccoli,
and cauliflower.
It must be emphasized that all plants
contain a mixture of soluble and insoluble
fibers. An overall increase in the consumption
of a variety of plants may: 1)
reduce the risk of developing Type 2 diabetes,
2) may help in lowering blood glucose
in those with Type 2 diabetes, 3) may
reduce cholesterol and cardiovascular
risk, and 4) may help lower body weight.
The presumed mechanism for weight
loss is based in the relative low-calorie
content of most high fiber foods. When
consumed in sufficient amounts, their
bulk will activate stretch receptors in the
stomach, contributing to a feeling of fullness
and achieve satiety at a lower total
caloric intake.
Conversely, insufficient fiber intake
has the opposite effect on the conditions
mentioned above.
Additionally, insufficient fiber intake
may also increase the risk for cancers of
the breast and colon.
In one study, premenopausal women
who ate six grams of soluble fiber a day
had a 62% lower risk for developing breast
cancer than those who consumed less than
four grams. Looking at a number of other
studies of fiber and breast cancer, it appears
that every 20 grams of total fiber intake a
day may be associated with a 15% lower
risk of breast cancer. The mechanism is
not clear, except that fiber appears to lower
blood estrogen levels, and reduced estrogen
stimulation of breast tissue appears to
lower cancer risk. Unfortunately, American
woman on average eat less than 15 grams
of fiber a day and this intake may be less
than needed to see fibers full benefit. The
Institute of Medicine recommendation for
women is 25 grams of fiber a day and for
men is 38 grams a day.
Insufficient fiber intake may also
increase the risk of colon cancer. In a
large, prospective, population-based
screening trial, total dietary fiber intake
was associated with a reduced risk of distal
colon adenoma, a precursor of colon
cancer, as well as distal colon cancer. In
this study fiber mediated protection
was most strongly associated with fiber
derived from cereals or fruit. Possible
mechanisms may include the dilution
of bowel carcinogens from increased
fiber or fiber derived alterations in the
gut bacterial species (microbiome). In
the latter instance, certain types of fiber
may serve as probiotic food sources for
the growth of healthy gut bacteria.
Increasing fiber in the diet may be
as simple as attempting to consume
more fruits and vegetables to achieve
the above defined fiber targets. But
how many fruits and vegetables are
enough? In research published in the
journal Circulation in 2021, two servings
of fruit and three servings of vegetables,
seemed the most effective combination.
When assessing products
and products containing grains, minimally
processed, whole grains are best.
For example, hulled barley, containing
both germ and fiber has the lowest glycemic
index of any grain and will raise
blood glucose gram for gram the least.
When in doubt about a product examining
the nutrition label and following
Dr. Michael Greger’s suggestion to eat
only those products having a ratio of
carbohydrate to fiber of five-to-one or
less is helpful.
In summary, fiber in Western
society has been largely removed in
processed food. The result may be
increased risk for diabetes, high cholesterol,
cardiovascular risk, increased
bodyweight, as well as an increased risk
of certain cancers. Returning to minimally
processed whole grains, fruits,
and vegetables will help lower risk.
Attempting to consume a minimum of
two servings of fruit
and three servings
of vegetables a day
rather than relying
on a fiber supplement
is more pleasant
and supplies
vitamins and antioxidants
as well.
Paul E. Lemanski, MD, MS, FACP
(plemanski3@gmail.com) is a boardcertified
internist practicing internal
medicine and lifestyle medicine in
Albany. Paul has a master’s degree
in human nutrition, he’s an assistant
clinical professor of medicine at
Albany Medical College, and a fellow
of the American College of Physicians.