Calcium & vitamin D supplements, trans-fats and cardiovascular risk.
I read with interest the meta-analysis by Bolland et al.(1) and I
note that the authors were careful to exclude trials that contained
vitamin D supplements on the grounds that a meta-analysis of vitamin D
supplementation has been shown to reduce mortality(2). Infact, in this
latter study by Autier & Gandini, 13 of the 18 included trials used
combined calcium & vitamin D supplementation and the inclusion of
trials containing calcium supplements did not affect the observed
improvement in total mortality with vitamin D supplementation. I was
therefore disappointed by the editorial by Cleland et al(3), which far
from adding clarity, confused plain calcium supplements together with
combined vitamin D preparations in the recommendations stated in their
final paragraph.
The literature on calcium and vitamin D supplementation and
cardiovascular risk is therefore by no-means clear. In such situations,
one needs to be careful to ensure that all possible known causes of
cardiovascular risk are carefully controlled for. In this regard, it came
as some surprise to me, to discover that most of the widely prescribed
combined calcium & vitamin D preparations contain amongst their
excipients hydrogenated or partially hydrogenated vegetable oils. Such
ingredients are strongly linked with cardiovascular disease(4). Infact
checking the summary of product characteristics(SPCs)(5) of the combined
calcium & vitamin D preparations listed in the british national
formulary(6), reveals that only 3 of the 10 available preparations are
free of hydrogenated or partially hydrogenated vegetable oil.
This situation is unlikely to be limited to the supplements in
question, as a search for the word "hydrogenated" of the SPCs of all UK
licensed medications reveals 97 hits, and one discovers that even
medications directed at reducing cardiovascular risk contain hydrogenated
oil.
I would be interested to know if any of the supplements included in
this latest meta-analysis are known to contain hydrogenated oils or trans-
fats. If a link to "trans-fats in medication" can be identified and
highlighted, perhaps steps can be taken to ban their inclusion in
medications, as is already being attempted in food.
(1) Bolland MJ, Avenell A, Baron JA, Grey A, MacLennan GS, Gamble GD,
et al. Effect of calcium supplements on risk of myocardial infarction and
cardiovascular events: meta-analysis. BMJ 2010;341:c3691
(2) Autier P, Gandini S. Vitamin D supplementation and total
mortality: a meta-analysis of randomized controlled trials. Arch Intern
Med 2007;167:1730-7.
(3) John G F Cleland, Klaus Witte, and Sue Steel. Calcium supplements
in people with osteoporosis. BMJ 2010; 341: c3856
(4) Mozaffarian D, Katan MB, Ascherio A, Stampfer MJ, Willett WC.
Trans fatty acids and cardiovascular disease. N Engl J Med. 2006 Apr
13;354(15):1601-13.
Rapid Response:
Calcium & vitamin D supplements, trans-fats and cardiovascular risk.
I read with interest the meta-analysis by Bolland et al.(1) and I
note that the authors were careful to exclude trials that contained
vitamin D supplements on the grounds that a meta-analysis of vitamin D
supplementation has been shown to reduce mortality(2). Infact, in this
latter study by Autier & Gandini, 13 of the 18 included trials used
combined calcium & vitamin D supplementation and the inclusion of
trials containing calcium supplements did not affect the observed
improvement in total mortality with vitamin D supplementation. I was
therefore disappointed by the editorial by Cleland et al(3), which far
from adding clarity, confused plain calcium supplements together with
combined vitamin D preparations in the recommendations stated in their
final paragraph.
The literature on calcium and vitamin D supplementation and
cardiovascular risk is therefore by no-means clear. In such situations,
one needs to be careful to ensure that all possible known causes of
cardiovascular risk are carefully controlled for. In this regard, it came
as some surprise to me, to discover that most of the widely prescribed
combined calcium & vitamin D preparations contain amongst their
excipients hydrogenated or partially hydrogenated vegetable oils. Such
ingredients are strongly linked with cardiovascular disease(4). Infact
checking the summary of product characteristics(SPCs)(5) of the combined
calcium & vitamin D preparations listed in the british national
formulary(6), reveals that only 3 of the 10 available preparations are
free of hydrogenated or partially hydrogenated vegetable oil.
This situation is unlikely to be limited to the supplements in
question, as a search for the word "hydrogenated" of the SPCs of all UK
licensed medications reveals 97 hits, and one discovers that even
medications directed at reducing cardiovascular risk contain hydrogenated
oil.
I would be interested to know if any of the supplements included in
this latest meta-analysis are known to contain hydrogenated oils or trans-
fats. If a link to "trans-fats in medication" can be identified and
highlighted, perhaps steps can be taken to ban their inclusion in
medications, as is already being attempted in food.
(1) Bolland MJ, Avenell A, Baron JA, Grey A, MacLennan GS, Gamble GD,
et al. Effect of calcium supplements on risk of myocardial infarction and
cardiovascular events: meta-analysis. BMJ 2010;341:c3691
(2) Autier P, Gandini S. Vitamin D supplementation and total
mortality: a meta-analysis of randomized controlled trials. Arch Intern
Med 2007;167:1730-7.
(3) John G F Cleland, Klaus Witte, and Sue Steel. Calcium supplements
in people with osteoporosis. BMJ 2010; 341: c3856
(4) Mozaffarian D, Katan MB, Ascherio A, Stampfer MJ, Willett WC.
Trans fatty acids and cardiovascular disease. N Engl J Med. 2006 Apr
13;354(15):1601-13.
(5) http//www.medicines.org.uk accessed 30th July 2010
(6) British National Formulary 59 March 2010
Competing interests:
None declared
Competing interests: No competing interests