A Conversation with Purdue University's Dr. Connie Weaver
The American Society for Nutrition (ASN) publishes some of the
world's most respected and widely read nutrition journals. The
Society also hosts a yearly clinical conference,
Advances and Controversies in Clinical Nutrition, which focuses
on critically appraising current nutrition controversies and
identifying opportunities for integrating evidence-based
research findings into clinical practice. At the 2012 meeting, Dr.
Connie Weaver, Head of the Department of Nutrition Science at
Purdue University, spoke about calcium and cardiovascular disease
risk. Dr. Weaver recently provided a follow-up to this current
health topic and discussed her experiences as an ASN member.
Interviewer: Would you tell us a bit about the recently
published article: “A Review
of Calcium Supplements and Cardiovascular Disease Risk”?
Dr. Weaver: There has been a lot of concern, of late,
regarding a potential association between calcium and Vitamin D
supplements and an increased risk of cardiovascular problems.
This concern stemmed from retrospective analysis of randomized,
controlled trials that were originally designed to test calcium and
Vitamin D supplementation against a placebo for bone health.
A group of New Zealand scientists reanalyzed these results,
however, and found that the supplements were also associated with
an increased risk of myocardial infarction. Obviously, these
concerns raised quite a few alarms, leading to additional analyses,
some of which have found no association and others that have found
other kinds of cardiovascular risks. There is not currently
any mechanistic explanation for these findings, but I argue that we
need more of this type of data before we jump to any kind of
Our research attempts to address that need via an animal model- a
pig on an atherogenic diet with metabolic syndrome and
atherosclerosis. We are currently completing a study in which
the pigs are given as needed calcium or high calcium either as
calcium carbonate supplements or as dairy. We are trying to
determine if more calcium accumulates in the soft tissue,
particularly the coronary artery, to determine if there is a
risk. To do so, we used a calcium tracer that measures very
small amounts of calcium in the arteries.
Interviewer: What is the future of calcium research? What
breakthroughs do you think are most promising for further
investigation, and what specific obstacles does it face?
Dr. Weaver: Calcium supplement sales have fallen off of late
due to the media attention about the potential association with
cardiovascular risk. Now, of course, that makes us worry
about bone health, since we have pretty firm evidence about the
benefits of calcium for bone. While patients are
understandably worried about the risks, we don't want to see those
benefits compromised. Our article was an attempt to summarize
what we know at this time and to point a way forward, using this
In regard to this one problem, it is difficult to convince the
scientific community whether this animal model can translate to
humans. Unfortunately, it is also difficult in humans to get
causal data because you can't randomize people to take calcium
supplements or placebo long enough, nor, obviously, can you sample
their artery to test calcium accumulation. So you are either
stuck with trusting what you see in an animal model or relying on
circumstantial evidence in humans.
Interviewer: Would you give us an overview of your talk at
the Advances & Controversies in Clinical Nutrition
Dr. Weaver: Well, that panel was related to this
problem. It was set up as a dialogue rather than a debate. I
worked with a cardiologist to answer questions directed by the
moderator or from the audience about how calcium supplements could
conceivably aggravate soft tissue calcification, whether that is
plausible, and whether the form of calcium matters. This
session was subsequently made available via
ASN's website, so the discussion expanded significantly even
after it was over.
Interviewer: What was your experience like as a presenter at
the meeting? What would you say to encourage investigators or
clinicians who may want to participate in the 2013 meeting?
Dr. Weaver: The wonderful thing about ACCN is that it has a
smaller, more intimate feel, especially in contrast to some of the
larger meetings like Experimental Biology. The size
difference allows for much more direct interaction between
panelists and audience members. You have a good chance for
dialogue on the spot. The webinar portion also gave us an
opportunity to expand the conversation and to address questions
that we may not have had time to get to during the session.
Interviewer: How did you first get involved in nutrition?
What motivated you to pursue a career in the field?
Dr. Weaver: I actually first got interested in nutrition as
a member of 4-H, when I was a kid. It really got me
interested in science and health.
Interviewer: How did you get involved with ASN? What
motivated you to join, and what aspects of membership have been
most helpful to your professional advancement?
Dr. Weaver: I joined ASN after attending Experimental
Biology in my first year as a professor at Purdue. The networking
has always been the number one benefit for me via both society
meetings and committees. ASN also does an excellent job of
staying abreast with public policy discussions and keeping members
informed about the aspects of those discussions with the potential
to impact our work. The organization has helped build
essential links between researchers, clinicians, and policymakers.
The publications, of course, are essential as well.