Chester J. Zelasko, Ph.D. |
January 27, 2006
Revolutions begin in
many ways. Sometimes we can point to a single event and say, “That was when
it began.” A little melodramatic? Perhaps--but I think it’s justified when
we talk about genetic testing.
In a recent review paper published in the Journal of the American
Medical Association, two scientists broached the topic of whether
public health policy should recommend essential nutrients from foods or from
dietary supplements (1). They came to the conclusion that when instituting
public health policy, nutrients should be derived from foods. That seems
like a frustrating statement for those of us who use dietary supplements on
a regular basis, but understand that this was a discussion of establishing
policy concerning the health of the general public, not optimizing health
for an individual. The arguments presented are well thought-out and valid.
However, in the last part of the paper, they presented a section on Targeted
Supplementation. Among several examples is the American Heart Association’s
recommendation that those people at risk for heart disease use a fish-oil
supplement every day (2). That last paragraph is the reason for this
Newsletter. They said that while we are in the infancy of understanding the
relationship between nutrition and the genetic code, a field called
the future will see targeted supplementation based on the
types of genes a person has.
This is a significant statement. You’ll have nutrients recommended not based
on someone’s opinion, not on a paper and pencil or computerized test, but on
the information found in your genetic code.
Why is genetic testing going to be important?
As a result of the Genome Project, scientists have mapped out the genetic
code of a human being--a remarkable project in itself. The problem is that
it will take decades to identify exactly what each part of this
3-billion-long code controls (3). The goal is to identify the parts of the
genetic code that are responsible for diseases, and the result will be
targeted pharmaceuticals that may help prevent the disease. A side benefit
is that it will also allow scientists to examine whether lifestyle factors
such as diet, exercise, and dietary supplements can mitigate those genes to
reduce the risk of disease. You’ve heard the expression that you are what
you eat? It may be truer than we ever imagined.
What is genetic testing?
Most people have watched a television show such as CSI and have seen the
investigators swab the inside of people’s mouths to collect their DNA. In
the genetic testing we’re talking about, the goal isn’t to find out your
genetic code to compare to someone else’s--it’s to find out if you have
specific parts of your genetic code that may put you at risk for developing
These specific parts of your genetic code are called Single Nucleotide
Polymorphisms, thankfully called SNPs for short and pronounced “snips.”
These SNPs will come in different forms--some may be positive, which may put
you at higher risk for developing a particular disease, and some that are
negative and may protect you from developing that disease.
Here’s the thing: even if you’ve inherited a SNP associated with a disease,
you may or may not get the disease. It’s not a done deal. Why? Because there
may be more SNPs involved in that disease. Also your lifestyle has a big
role to play in whether those genes are ever expressed (turned on). The
reason it’s important to know what SNPs you have is that when you know, you
can adjust your lifestyle to reduce the risk of developing the disease, and
that may include targeted supplementation. Pretty remarkable, isn’t it?
I’ll be writing more about this in the future as more is discovered. This is
an exciting time in the health field. Based on genetic testing, we may be
able to know exactly what type of diet you should eat, what type of exercise
you’d respond to best, what type of nutrients you should eat, and others you
should avoid. So stay tuned--the revolution in health has just begun. As Pat
Zifferblatt, the owner of Better Life loves to say, “The best is yet to
- Lichtenstein, AH and Russell, RM Essential Nutrients: Food or
Supplements? Where Should the Emphasis Be? JAMA. 2005;294:351-358.
- Kris-Etherton PM, et al. American Heart Association Nutrition
Committee. Fish consumption, fish oil, omega-3 fatty acids, and
cardiovascular disease. Circulation. 2002;106: 2747-2757.
- Oak Ridge National Laboratory.
Featured Sites, then Human Genome Project Section.