Dr Andersen discusses the problem
of data manipulation and how to beat it.
I do not care what the truth is; I just want to know it. And when it
comes to dietary supplements, the truth can be hard to find for a number
of reasons. When a recent headline stated that multivitamins are a waste
of money, 1 it prompted today’s analysis on interpretation and comprehension
of dietary supplement research.
Contradictions: This is the biggest problem for the public because so
many headlines from large studies seem to routinely conflict. Take for
example two of the best selling supplements, calcium and omega-3 fatty
acids. In February of 2013 a large Swedish study reported that women who
took calcium supplements had doubled their chances for heart attack and
had a higher mortality rate than women who did not take calcium.2 In May
2013 a Canadian study found that calcium supplements up to 1000 mg a day
lowered mortality rates.3 In April 2013 seniors with the highest blood
levels of omega-3’s had the lowest death rates 4 and in July men
with the highest blood omega-3 levels had the highest rates of aggressive
prostate cancer. 5
Bias: Alternative medicine tends to embrace positive studies and is skeptical
of negative studies. Mainstream medicine takes the opposite approach,
or, as I like to say ‘One side is quick to praise and the other
side is quick to condemn.’ Many times the bias is related to secondary
gain issues because both positive studies and negative studies affect
where consumers spend their money. In any event, when groups overemphasize,
over generalize and/or spin by omission the result hurts everyone.
Misinterpretation: Most of our nutrition news comes from sound bites which,
in general, come from press releases and/or abstracts. Anyone who reads
scientific papers knows abstracts do not always tell the whole story —
and press releases can be even more misleading. In fact, most of the public
and many professionals get supplement news from a summarized summery which
makes the odds of misinterpretation higher than anybody would like. And
that’s before the information is manipulated by advertisers to sell
products.
Confusion: It’s pretty obvious that the headlines can be confusing
for healthcare professionals, let alone our patients. The good news is
that bias, misinterpretation and confusion can really decline when we
read the entire study from the original authors. Just knowing how the
study was done and all of the results allows a person to evaluate both
the reporting and the response to what we hear from the media Unfortunately,
few have the time evaluate the source of whatever conclusion makes headlines.
In turn many people make the mistake of taking or not taking something
based on group percentages rather than determining if their individual
intake is adequate.
Here is what I tell my patients:
Dietary supplements provide what an individual’s diet lacks. It’s
like putting air in your tires: the lower the tire pressure is, the more
air your tire needs and the more you feel the difference when the ‘air
deficiency’ is treated. But once you have enough air, more is not
better. Unfortunately, most people take dietary supplements based on either
media reports or what a friend or acquaintance tells them. Using the tire
analogy, they put air in their tires without reading the gauge to see
if they’re low or re-reading the gauge to see when they have enough.
So when a news report of a large study states ‘Most people do not
have enough air in their tires’, it does not mean your tires need
air. For that information, you must check your own tires.
Here is what I tell health professionals:
1. If a person’s diet lacks a nutrient or a person has a temporary
increase in a requirement for a nutrient, supplementing will yield great
results.
2. Never take (or recommend) a supplement based on a population deficiency.
Just because most people in the group studied didn’t get enough
of whatever was studied doesn’t mean an individual has a deficit.
3. In general, the people who need supplements the most take them the
least, and the people who need them the least take them the most.
Finally, to discuss the studies I used as examples, regarding calcium
taking supplements when diet provides more than enough (i.e. it is NOT
needed) is unwise and can be harmful. 2 Many misinterpreted this to mean
calcium pills will cause heart attacks rather than taking high supplemental
doses with zero needs for any supplemental calcium can be unhealthy. On
the flip side, getting enough (but not too much) calcium is healthy. 3
In the two omega-3 studies I used which, at the times they were released,
were used to either support 4 or oppose 5 the use of fish oil pills, neither
study actually was on omega-3 supplements. In both cases, blood levels
of omega-3 fatty acids were measured and conclusions were made on those
values. Those who took the time to read the research discovered that the
study which concluded fish oil supplements could lead to prostate cancer
got their data from a vitamin E and selenium study. 5 As for the ‘multivitamins
are a waste of money’ commentary1, we will take a closer look at
the validity of that statement in the future. In the meantime, taking
any dietary supplement that isn’t needed doesn’t make sense
– nor does it make sense for an individual to start or stop any
dietary supplement based on advice from a person unfamiliar with their
diet.
1. Guallar E Saverio Stranges S, Cynthia Mulrow C. et al. Enough Is Enough:
Stop Wasting Money on Vitamin and Mineral Supplements . Annals of Internal
Medicine 17 December 2013, Vol 159, No. 12
2. Michaëlsson K Melhus H. et al. Long term calcium intake and rates
of all cause and cardiovascular mortality: community based prospective
longitudinal cohort study BMJ. 13 February 2013;346:f228
3. Langsetmo L, Berger C, Kreiger N, et al. Calcium and vitamin D intake
and mortality: results from the Canadian Multicentre Osteoporosis Study
(CaMos). J Clin Endocrinol Metab. 2013 Jul;98(7):3010-8. doi: 10.1210/jc.2013-1516.
Epub 2013 May 23.
4. Mozaffarian D; Lemaitre RN, Irena B. King, IB. et al. Plasma Phospholipid
Long-Chain ?-3 Fatty Acids and Total and Cause-Specific Mortality in Older
Adults: A Cohort Study. 2 April 2013 Ann Intern Med. 2013;158(7):515-525.
doi:10.7326/0003-4819-158-7-201304020-00003
5. Brasky TM, Darke AK, Song X, et al. Phospholipid Fatty Acids and Prostate
Cancer Risk in the SELECT Trial. J Natl Cancer Inst. 2013 Jul 10. [Epub
ahead of print] Accessed July 21, 2013
916 E. Imperial Hwy.
Brea, CA. 92821
(714) 990-0824
Fax: (714) 990-1917
gdandersen@earthlink.net
www.andersenchiro.com
Copyright 2004, G. Douglas Andersen,
DC, DACBSP, CCN, 916 E. Imperial Hwy, Brea, CA 92821, (714) 990-0824
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