Study closes debate on folic acid and heart disease
Taking folic acid doesn’t lower risk of heart disease
(Medical Xpress) -- Taking folic acid supplements is not going to have any meaningful effect on your risk of coronary heart disease.
Thats the conclusion of a comprehensive study led by Oxford University researchers that pretty much closes the door on this debate once and for all.
The possibility that folic acid might help prevent heart disease has attracted considerable interest over the last two decades understandably, because folic acid pills would have been an attractive, simple and cheap measure to reduce peoples heart disease risk. But studies have often provided conflicting evidence on whether it helps.
Folic acid lowers levels of the amino acid, homocysteine, in the blood. It was thought that this would be beneficial because raised levels of homocysteine have been linked with coronary heart disease.
However, the Oxford researchers recently reported that taking folic acid supplements has no effect on reducing heart disease risk, through a large meta-analysis of data from randomised clinical trials.
Now, in a large-scale genetics study published in PLoS Medicine, they and their colleagues demonstrate that the reasoning behind the interest in folic acid doesnt hold either: there is no link between high homocysteine levels and your likelihood of developing coronary heart disease.
With the evidence from genetic studies and clinical trials both arguing against the use of folic acid supplements, the researchers say the debate is over.
"After two decades of research, this report provides a definitive answer to this question and refutes the relevance of use of folic acid for primary prevention of coronary heart disease," states Dr. Robert Clarke of the Clinical Trial Service Unit at Oxford University, who led the study.
The international group of researchers involved in the new study were interested to understand whether people whose genes lead them to have slightly higher levels of homocysteine throughout life have any extra risk of coronary heart disease.
The MTHFR gene encodes an enzyme which metabolises homocysteine, removing it from the body. But a single change in the DNA code, inserting a T for a C, reduces the enzymes efficiency.
Individuals with two copies of the altered gene have homocysteine levels that are about 20% higher than those with the more common gene variant.
This makes the gene a very good tool for studying whether homocysteine levels influence coronary heart disease risk.
However, the research team found that among 48,000 individuals with coronary heart disease and 68,000 controls, people who had the MTHFR gene variant did not have an increased risk of developing coronary heart disease.
The major new step taken by the researchers was to include 19 previously unpublished datasets involving 48,000 additional coronary heart disease cases in their analysis.
It was these unpublished data that drove the conclusion that high homocysteine levels do not have any effect on coronary heart disease.
The researchers suggest that publication bias (where more positive results tend to get published in scientific journals over negative findings) played a role in previous suggestions linking homocysteine with coronary heart disease risk, together with methodological problems in some studies.
Homocysteine is produced in the body from methionine, an essential amino acid found in large amounts in meat, eggs and milk.
"Some believed that elevated homocysteine causes damage to the inner lining of blood vessels," explains Dr. Clarke. "However, elevated homocysteine levels are closely correlated with known risk factors, such as smoking, high blood pressure and high cholesterol. In retrospect, elevated homocysteine levels are probably a marker of cardiovascular disease rather than being causal."
The study was funded by the British Heart Foundation and UK Medical Research Council.
Provided by Oxford University
- High blood homocysteine levels are not linked with coronary heart disease Feb 21, 2012 | not rated yet | 0
- Use folic acid to cut heart disease, say experts Nov 27, 2006 | not rated yet | 0
- Folic acid no help for heart and blood vessels May 12, 2011 | not rated yet | 0
- Study examines outcomes of lowering homocysteine levels with folic acid and vitamin B12 Jun 22, 2010 | not rated yet | 0
- Meta-analysis shows no heart benefits for folic acid supplements Oct 11, 2010 | not rated yet | 0
- Motion perception revisited: High Phi effect challenges established motion perception assumptions Apr 23, 2013 | 3 / 5 (2) | 2
- Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update) Apr 02, 2013 | 4.5 / 5 (11) | 5
- The visual system as economist: Neural resource allocation in visual adaptation Mar 30, 2013 | 5 / 5 (2) | 9
- Separate lives: Neuronal and organismal lifespans decoupled Mar 27, 2013 | 4.9 / 5 (8) | 0
- Sizing things up: The evolutionary neurobiology of scale invariance Feb 28, 2013 | 4.8 / 5 (10) | 14
Specific Exergy vs Specific Flow Exergy
1 hour ago I'm having some difficulty understanding exactly what the difference between the definitions of these values are. As I understand it, in terms of...
The Durability of Bone: Long Falls
9 hours ago I am doing a paper on the physics in Valve's Portal and got interested in the "Long Fall Boots" that prevent any damage no matter how far you fall. I...
Is energy convertible to matter?
11 hours ago Can we convert energy to matter?
Rotating electron as a dipole is this right?
13 hours ago An electron as shown by the Stern Gerlach experiment behaves like a dipole (albeit only in one of two states). I have been trying to figure out how...
Dipole term in multipole expansion
17 hours ago Hi. I'm having some difficult in understanding something about the dipole term in a multipole expansion. Griffiths writes the expansion as a sum of...
Bubbles in a Pre-Boiling/Boiling pot of water
18 hours ago How is it that bubbles form on the bottom of a surface of a pot of boiling water? I think that there is probably an elementary answer to this...
- More from Physics Forums - Classical Physics
More news stories
The Orsiro stent, which is a novel stent platform eluting sirolimus from a biodegradable polymer, demonstrated non-inferiority to the Xience Prime everolimus-eluting stent for the primary angiographic endpoint of in-stent ...
Cardiology 14 hours ago | 5 / 5 (1) | 0
One-year results from SOURCE XT – one of the largest, post-approval transcatheter aortic valve implantation (TAVI) registries to-date – reported today at EuroPCR 2013 show good clinical outcomes in routine clinical practice, ...
Cardiology 14 hours ago | not rated yet | 0
A drug commonly used to treat depression and anxiety may improve a stress-related heart condition in people with stable coronary heart disease, according to researchers at Duke Medicine.
Cardiology 15 hours ago | 5 / 5 (1) | 0 |
(Medical Xpress)—In a recent subgroup analysis of the largest blood pressure treatment trial in history, University of Alabama at Birmingham (UAB) researchers found that women and men react the same to ...
Cardiology 23 hours ago | 5 / 5 (1) | 0
Medical researchers discover new ways to target, develop and design drugs to prevent and treat viral infection
Researchers at the University of Alberta have discovered a new drug target, developed a new drug and identified a new way to design drugs—all of which could be a winning combination in the battle against viruses.
9 minutes ago | not rated yet | 0 |
Italian lawmakers on Wednesday gave their final approval to a law that allows limited use of a controversial type of stem cell therapy which has been condemned by many scientists but has given hope to families of terminally-ill ...
49 minutes ago | not rated yet | 0
Beta-blockers, normally used for high blood pressure, could enhance the effectiveness of chemotherapies in treating neuroblastoma, a type of children's cancer, according to a new study published in the British Jo ...
19 minutes ago | not rated yet | 0
Cancer survivors are no more likely to stop smoking, cut down on alcohol, or exercise more often than the general population, according to new research published in the British Journal of Cancer today (Wednesday)
9 minutes ago | not rated yet | 0
(Medical Xpress)—Do ethicists engage in better moral behavior than other professors? The answer is no. Nor are they more likely than nonethicists to act according to values they espouse, according to researchers from the ...
8 minutes ago | not rated yet | 0
A Japanese cancer specialist said Wednesday she has started the world's first clinical trial of a powerful, non-surgical, short-term radiation therapy for breast cancer.
29 minutes ago | not rated yet | 0