Bias in Favor of Nutritional Supplements
Douglas Andersen, DC, DACBSP, CCN
Volume 22, number 21, 10/07/04, page 16
It is important to remember, that many DC's only get half the story (re:
supplements) and need both sides to make the best rx.
Last summer I struck up a conversation with a registered dietitian (RD) at a sports nutrition conference. We,
along with 2 others (a coach and an exercise physiologist), had approached one of the speakers after his talk
and began to ask him questions. The speaker harshly blew off my question. I was stunned. The others then
asked their questions. I then asked a second question, this time citing his research and 2 other recent papers,
and again the response was the same. At this point, everyone realized there was a problem. The next question
was not directed to the speaker, but to me instead. As I began my answer the speaker turned and rapidly exited
the room. As soon as he was gone, the coach asked, "What was wrong with him? You know your stuff." Before I
could answer, the RD said, "It was his name tag." The physiologist said "What?" I said, "After I asked my
question, he glanced at my name tag and had an immediate attitude change." The coach said, "I don't
understand." The RD answered, "He is clearly bias against chiropractors."
It was one of the last talks of the day and, as I walked to the car, I continued to talk with the dietitian. She
said, "Speaking of bias, I feel that my education was biased against the use of supplements. Most of the people
attending this conference seemed so knowledgeable about supplements, especially positive studies that I was not
aware of. I feel short-changed." My response was "Well, if it makes you feel any better, my training had a
pro-supplement bias, and since I have been in practice I get more exposure from representatives, companies,
and literature that has a 'positive spin.' She asked, "So, what do you do about it?" I said, "The most
important thing is not whether your education was biased in either a positive or negative way, but that you
are aware of it. You should also be aware of any bias your information sources may have. In my case I
subscribe to both conservative and progressive publications."
If you feel you may have a bias in favor of nutritional supplements, it will be easier for you to embrace
nutritional supplements in the following categories:
- A new supplement.
- A new supplement formula.
- A new supplement form.
- A new supplement use.
The following 4 examples all happened this year:
A New Supplement
New supplements are often touted as cure-alls. Rarely will you encounter this type of product through a
professional company catering to alternative health practitioners. In most cases, you will be exposed to these
products through a multilevel approach, an infomercial, or a TV, radio, or magazine advertising blitzkrieg. Recently,
a product came across my desk that was given to me by a colleague who wanted me to check it out and possibly
endorse it. He said his patients really liked it. The literature provided by the company stated that this
fruit extract was (according to the MD who endorsed it) now his first-line therapy for gastritis, hiatal hernia,
arthritis, fibromyalgia, low energy, mild depression, mild to moderate anxiety, mild to moderate asthma, irritable
bowel disease, recurrent urinary tract infections, diverticulitis, sleep disorders, allergic rhinitis,
neurodermatitis, eczema, seborrhea, otitis externa, and nonarthritic muscle or joint pain. In the company
handouts, it stated that the benefits of the juice of this tropical fruit were "validated through clinical
studies." They also provided a research web site that would describe these studies. I got on the web site,
plugged in the fruit extract, and hit search. The result was 17 papers with very impressive titles. When I
began to read them, I realized that in every case they were in vitro laboratory studies, most of which tended
to be of the cell culture variety. Using the same web site, I then plugged in the fruit extract again, this
time with each condition the MD spokesperson said it should be used for. In every case, when a search was done,
the result was the same: No items found. I told my friend that if sales take off, the company better have a
A New Supplement Formula
Early in the year a representative from a well-known company came to my office and asked me if I was interested
in a new herbal based product that was a better anti-inflammatory than any others on the market (due to the unique
combination of ingredients). I said, "Yes, I am interested. Is there research behind it?" Her answer was
"Yes." I then said, "I will be happy to look at your literature, but I will disregard any research done on cell
cultures in laboratories, studies on mice and rats, and proprietary in-house studies." She said "Fine," and gave
me a very impressive 4 page color handout with great charts and graphs. I scanned the handout and flipped to the
back page. I then said "No, thanks." Her facial expression indicated my reaction was completely unexpected. I
said, "Look at the references" and went down the list-proprietary, proprietary, cell culture, cell culture, mouse,
rat, rats and mice. I asked, "Would you want me to sell or recommend a product to your mother based on how well
it works on a rodent or on a study performed by the company selling the product that was not published in a
A New Supplement Form
A few weeks later another representative came to my office. She was ready for me. She had a stack of handouts
with references. As we went through her product line, she mentioned that she was selling a new form of a popular
product. She stated, "The form everyone else uses is harmful." "Oh really," I said. "Do you have evidence of
this?" She said, "Yes" and gave me a handout. I read it and, sure enough, there was a study that showed high
amounts were harmful to rodents. As I continued to flip through her literature, I found another product they
marketed that also contained the ingredient in question. This handout extolled the benefits of this ingredient.
They listed over 10 studies, all of which were done on humans, all of which showed various degrees of benefit, and
all of which used the 'harmful' form. When I pointed this out, her jaw dropped and she said, "I need to call my
A New Supplement Use
Whenever you hear of a new use for a product that is also a clue to put your skeptic hat on. Recently, a
representative was telling me about the virtues of a product when he said "Oh, and by the way, did you know that
it also lowers blood pressure?" I thought to myself, Wow! High blood pressure is a major problem. I stated I
had not heard that this product lowers blood pressure. Where is the data? He then gave me a literature sheet
about the product. Sure enough, there were plenty of references for its intended use. As I scanned the
literature, he pointed out a line and said "See? It lowers blood pressure." Sure enough, it said this product
lowers blood pressure. I said "But this statement has no reference. Not only that, it has no recommendation
on a dose to lower blood pressure, nor does it explain how much it can lower blood pressure or how long it will
take to lower blood pressure."
All of the above stories are true. DC's, their patients, and other professionals are buying these products
and others like them. I doubt anyone without bias (let alone a negative bias) would purchase any of these
supplements for the reasons given at this time. And a substance or product that in itself is not harmful can
still cause harm if it prevents or delays a safe and proven treatment. Many chiropractors and alternative
practitioners are well trained on how to recognize negative bias. It is this author's opinion that we must
use this training and apply it to information with a positive bias as well. As for the examples cited, if I
get any evidence supporting or refuting the claims made, I will write it up, and name names. In the meantime,
an error based on bias is an error regardless of whether the bias is positive or negative.
For articles on negative bias see Dr Andersen's 2 part series titled Medical Bias and Supplements, Part I: Multiple Vitamins. Dynamic Chiropractic 18:7, 3/20/00;
Medical Bias and Supplements, Part II: Vitamin C and Kidney Stones. Dynamic Chiropractic 18:9, 4/17/00.
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2004, G. Douglas Andersen, DC, DACBSP, CCN, 916 E. Imperial Hwy, Brea,
CA 92821, (714) 990-0824