Wednesday, October 17, 2007

Homocysteine Bad For Eyes

Science Daily reported on a study today that suggests homocysteine, an amino acid linked to heart attack, stroke and dementia, may also be a player in retinal damage and vision loss. Although the writer's explaination of methionine metabolism is way too simplistic, we will present the material just as they did in Science Daily.

....The study leader, Dr. Sylvis Smith of the Medical College of Georgia, explained that homocysteine levels rise when folic acid levels drop, a problem for many whose diets are poor in folate-rich fruits, tomatoes, vegetables and grains. Smith exposed layers of retina to high levels of homocysteine and found the retina "terribly disrupted."

"Folate and vitamin B12 convert homocysteine to methionine, an amino acid essential to protein synthesis. Without the conversion, rising homocysteine levels interfere with the folding and structure of collagen, a component of bone, tissue and the basement membrane of blood vessel walls," Smith said.

"At any point in your life, too much homocysteine can be problematic, whether you are talking about pregnant women, cardiovascular disease or dementia," Smith says in a statement. "If homocysteine is not converted into methionine or cysteine -- by vitamin B6 -- to aid protein synthesis, it can do something bad."


Dan R. said...

Is there enough B6, B12 and folate in Macula Complete to control homocysteine levels?

Ellen Troyer, MT MA said...

Hi Dan,

This is the level of B12 and Folate considered best for optimal methionine metabolism.

Homocysteine is a natural by-product of methionine metabolism.

Excess homocysteine is converted back to cysteine and flushed from the body if adequate B6 is available.

Maggie S said...

If methionine metabolism produces homocysteine, why on earth would we want to enhance that metabolism with B12 and Folate?

Ellen Troyer, MT MA said...

Methionine is one of the eight essential amino acids required to form or build complete proteins - meaning that we must obtain methionine from our diet.

It's absolutely necessary for cardiac and brain neurotransmitter function, so it's essential that our dietary intake also include the nutrient co-factors necessary to facilitate methionine metabolism.

Jake W said...

What is the normal level of homocysteine and why isn't my doctor checking my homocysteine level during my yearly physical?

I take Oculair every day so I should be OK, right?

Ellen Troyer, MT MA said...

Unfortunately, mainstream medicine has been very slow to recognize the dangers of excessive homocysteine. Probably because it can be controlled with vitamins and most medical doctors don't read nutrition or biochemistry journals.

Homocysteine Values

Normal level - 5 to 15
Moderate - 16 to 30
Intermediate - 31 - 100
Severe - above 100

Our position is that everyone should try to keep their homocysteine level under 10 since excessive homocysteine is now linked to so many degenerative diseases, particular vascular disease, which almost always leads to degenerative eye disease of one kind or another.

Disgusted in Maryland said...

This blog discussion, as with many others happening all over the internet, points out the negligence of the AREDs2 formulation committee.

The B vitamins would have been included in that formulation, if the purpose had been to best serve nutrition science the AMD patient community.

Could it be that this group is saving B vitamins for seven years from now so they can continue their research gig with an ARED3 study that includes these vitamins? Talk about planned job security!!!

In the meantime, constipated retinal specialists will continue to recommend B&L's stupid little ARED formulation, and they will continue telling their patients that's the only science that counts.

Steve Whiting, PhD said...

I don't agree that the ARED formulation is stupid, given the fact that it was designed in the late 1980s or early 90s, albeit not being designed by those who actually understood the biochemistry enough to know to include copper to prevent zinc induced anemia.

What is disconcerting is that too many eye care professionals refuse to acknowledge that nutrition, biochemistry, genome and molecular biology science has progressed way past the information available when the first, or second for that matter, ARED formulations were designed.

Apparently, acknowledging science that's not an integral part of their specialty is difficult for some eye care professionals.

Jeffrey Anshel, OD said...

Hmm, is this "new" information? I've had this info in my lecture for about a year....!!!

Ellen Troyer, MT MA said...

It's not new science, it just takes some people a long time to acknowledge most science - the excess homocysteine connection to eye disease studies (with live links to the National Library of Medicine abstracts) have been included in the scientific rationale section of the Biosyntrx web site for well over three years.

Anonymous said...

I have been legally blind for the past fifty years. No definitive diagnosis has ever been made other than retinal dystrophy or cone rod disease.
My recent physical shows a homocysteine level of 18. My doctor has prescribed Metanx, a vitamin with very high doses of B6, Folic Acid, and B12. He is treating the high level of homocysteine, but it would be more than a little interesting if I were to see an improvement in my sight.