BY RALPH BLUM
My concern—and hence our looking
backward in time— is with the beneficial impact of reduced caloric intake on retarding,
and in some cases reducing, the spread of prostate cancer. Dietary restriction,
as I noted in our last blog, seems to trigger an ancient strategy written into
all animal genomes, that when food is scarce, resources are switched from
breeding to tissue maintenance.
In recent years biologists had
considerable success in identifying the mechanisms by which cells detect the
level of nutrients available to the body. One goal now is to find drugs that
trick these mechanisms into thinking that famine is at hand. The positive
results even include evidence that the immune system benefits from reduced
caloric intake, and that there is a connection between brain function and
adipose tissue in relation to obesity.
A recent study in PLOS Biology
discusses the relationship between LDL, hunger, leptin, the brain, and the
benefits in a number of areas: there is a ubiquitous
receptor in the brain, adipose, and liver called the low-density lipoprotein
receptor-related protein 1 (LRP1)
which regulates leptin signaling. LRP1 has some of the following properties:
lipoprotein metabolism, neurotransmission, synaptic plasticity (adaptability of
the neuronal junctions), clearance of beta amyloid. (note the variant epoE4 of
epoE is associated with Alzheimer's Disease), and basic cell survival.
There is now a small subculture whose
members seek good health through a selective return to the habits of their
Paleolithic ancestors. Or as they sometimes
refer to themselves, “dietary cavemen.”
Their interpretation of this metaphor involves fasting between meals to
approximate the lean times that his distant ancestors faced between hunts.
Vegetables and fruit are appropriate, but they avoid foods like bread and pasta
that were unavailable before the invention of agriculture. These Dietary
Cavemen are convinced that the human body evolved from a
hunter-gatherer lifestyle, and that our survival in today's world depends
weaning ourselves off many millenniums of bad habits.
if you will that you are a caveman, out innocently picking berries
when you suddenly come nose to nose with a saber-tooth tiger. While you were
simply gathering, the tiger was actually hunting, and the sight of you makes
his mouth water.
It is our good fortune that millions
of years of evolution have endowed you with a set of responses that take over
automatically in the event of an emergency. Faced with the tiger, your
hypothalamus sends a message to your adrenal glands and within seconds, you can
run faster, hit harder, hear more acutely, think faster, and jump higher than you
could only seconds earlier.
The transformation is instantaneous.
In a heartbeat, so to speak, your heart is pumping at two to three times the
normal speed, sending nutrient rich blood to the major muscles in your arms and
legs. The tiny blood vessels (called capillaries) under the surface of your
skin close down so you can sustain a surface wound and not bleed to death. Even
your eyes dilate so you can see better.
In the same instant, all functions of
your body not required for the life-saving struggle about to commence are shut
down. Digestion stops; ditto sexual function; even your immune system is
temporarily turned off. If necessary, excess waste is eliminated to make you
light on your feet.
Your suddenly supercharged body is
designed to help improve the odds of survival, with the
result that you narrowly escape death. Once the danger is past, you find a safe
place to lie down and rest your exhausted body. Much the same situation appears
to apply when your “attacker” is prostate
In my next blog I will consider the elements
of a diet that increases the possibility of such survival.