And then there’s
budget politics
By
Will Collette
I
closely follow developments in science, especially those that may affect those
near and dear to me (including myself). So I was surprised to see to two articles released the same day on the same study in Science Daily that discussed the value of using Vitamin D supplements to reduce cancer risk.
The
Creighton University article, immediately below, found a 30% lesser risk among
patients taking Vitamin D supplements.
However,
JAMA – the Journal of the American Medical Association – article on the Creighton University study takes a very different spin, concluding that use of
Vitamin D and calcium supplements produced no significant decrease in cancer
risk among menopausal women.
So
you can read and judge for yourself, I have reprinted both Science Daily
articles on this subject.
There was one point of consensus between the two
articles and that is more research is needed.
Whether
that research actually happens may depend in large part on how deeply Trump and
the Republican-controlled Congress cut the budget for medical research. Just
days ago, Trump suggested a 20% cut - $1.2 billion – to the research budget for
the National Institutes of Health.
He
needs the money for military spending and to build his Border Wall.
Here are the two contending articles:
Vitamin
D decreases risk of cancer, new
study suggests
Creighton University
Increasing vitamin D levels may lower risk for developing
cancer, according to a study conducted by Creighton University with cooperation
from the University of California San Diego. The results of the study were
released today in the Journal of the American Medical Association.
The study, funded by the National Institutes of Health, is a randomized
clinical trial of the effects of vitamin D supplementation on all types of cancer
combined.
The four-year study included 2,303 healthy postmenopausal women
55 years and older from 31 counties in Nebraska. Participants were randomly
assigned to take either 2000 international units (IU) of vitamin D3 and 1500
mg. of calcium or identical placebos daily for 4 years.
The vitamin D3 dose was
about three times the US government's Recommended Dietary Allowance (RDA) of
600 IU for adults through age 70, and 800 IU for those 71 and older.
Women who were given vitamin D3 and calcium supplements had 30%
lower risk of cancer. This difference in cancer incidence rates between groups
did not quite reach statistical significance.
However, in further analyses,
blood levels of vitamin D, specifically 25-hydroxyvitamin D (25(OH)D), were
significantly lower in women who developed cancer during the study than in
those who remained healthy.
The average 25(OH)D level in the women's blood at the beginning
of the study (33 nanograms/milliliter, ng/mL) was higher than the usual target
levels that currently range from 20-32 ng/ml, according to different sources.
This suggests that higher vitamin D levels than are currently recommended are
needed for substantially decreasing risk of cancer.
"This study suggests that higher levels of 25(OH)D in the
blood are associated with lower cancer risk," said principal investigator
Joan Lappe, PhD, RN, Creighton University Criss/Beirne Professor of Nursing and
Professor of Medicine.
"The study provides evidence that higher
concentrations of 25(OH)D in the blood, in the context of vitamin D3 and
calcium supplementation, decrease risk of cancer" she said. These results
contribute to a growing body of scientific findings, including results of a
similar randomized controlled clinical trial preceding this one in Nebraska women,
that indicate that vitamin D is a critical tool in fighting cancer" she
said.
"It is also of value in preventing other diseases, according to
previous research," Lappe said.
Other Creighton researchers involved in the study included
Robert Recker, M.D., Dianne Travers-Gustafson, Ph.D., R.N., and Patrice Watson,
Ph.D. University of California San Diego Professors Cedric F. Garland, Dr.P.H.,
F.A.C.E. and Edward D. Gorham, Ph.D., were co-investigators.
Professor Robert
P. Heaney of Creighton University, who died August 6, 2016, played a key role
in inspiring and planning this study. Heaney was the acknowledged world expert
on the physiology of vitamin D and calcium and their relationship to several
major diseases.
According to Lappe, most cells in the body need vitamin D to
function properly. "Without adequate vitamin D, normally functioning cells
can convert to malignant cells." Lappe said.
Cedric Garland, a co-investigator at the University of
California San Diego said "This is the most important scientific study of
this century to date." The study was open to all ethnic groups, but most
of the participants were Caucasian, which Lappe said matched the population in
the rural counties in Nebraska.
Lappe said further studies are needed to
determine if these research results apply equally to men and to other ethnic
groups.
"While people can make their own vitamin D3 when they are
in the sun near mid-day, sunscreen blocks most vitamin D production. Also, due
to more time spent indoors, many individuals are lacking adequate levels of
vitamin D compounds in their blood," Lappe said.
"The results of this
study lend credence to a call for more attention to the importance of vitamin D
in human health and specifically in preventing cancer" Lappe said.
Vitamin
D, calcium supplementation among older women does not
significantly reduce risk of cancer
The JAMA Network Journals
Among healthy postmenopausal women, supplementation with vitamin
D3 and calcium compared with placebo did not result in a significantly lower
risk of cancer after four years, according to a study published by JAMA.
About 40 percent of the U.S. population will have a cancer
diagnosis at some point during their lives.
Evidence suggests that low vitamin
D status may increase the risk of cancer, and considerable interest exists in
the potential role of vitamin D for prevention of cancer.
Joan Lappe, Ph.D.,
R.N., of the Creighton University Schools of Nursing and Medicine, Omaha, and
colleagues randomly assigned 2,303 healthy postmenopausal women 55 years or
older (average age, 65 years) to the treatment group (n=1,156; 2,000 IU/d of
vitamin D3 and 1,500 mg/d of calcium) or to the placebo group (n=1,147).
Duration of treatment was four years.
The researchers examined the incidence of
all-type cancer (excluding nonmelanoma skin cancers).
A new diagnosis of cancer was confirmed in 109 participants, 45
(3.89 percent) in the vitamin D3 + calcium group and 64 (5.58 percent) in the
placebo group (difference, 1.69 percent).
Incidence over four years was 0.042
in the treatment group and 0.060 in the placebo group. There was no statistically
significant difference between the treatment groups in incidence of breast
cancer.
Adverse events potentially related to the study included kidney
stones (16 participants in the treatment group and 10 in the placebo group) and
elevated serum calcium levels (six in the treatment group and two in the
placebo group).
The authors write that one explanation for lack of statistically
significant differences between the treatment groups in all-type cancer
incidence is that the study group had higher baseline vitamin D (serum
25-hydroxyvitamin D) levels compared with the U.S. population.
"Further research is necessary to assess the possible role
of vitamin D in cancer prevention."
