Homocysteine is a naturally-occurring amino acid found in your blood plasma.
Having high homocysteine levels might increase your risk of heart disease, Alzheimer's disease, stroke, and osteoporosis.
What are the newly-identified risks of excess homocysteine?
A recent study, published in 2014, looked at people with high homocysteine and uric acid and found that there was a 10.5-fold greater risk of vascular dementia.
Other studies show that homocysteine could increase your Alzheimer's risk, worsen diabetic complications, and contribute to an increased rate of brain atrophy.
What else do you need to know about homocysteine?
Listen in as Dr. Mike discusses homocysteine and the newly-identified risks of having excess homocysteine.
Selected Podcast
Newly Identified Risks of Excess Homocysteine
Transcription:
RadioMD Presents:Healthy Talk | Original Air Date: May 14, 2015
Host: Michael Smith, MD
Healthy Talk with Dr. Michael Smith, M.D. And now here's the country doctor with a city education, Dr. Mike.
DR MIKE: So, I want to talk about homocysteine. Specifically, I want to talk about some newly identified risks of having too much homocysteine in your body. I think in the medical community most doctors accept now homocysteine or high levels of homocysteine as a risk factor for heart disease.
But new research is showing that it can also impact dementia, Alzheimer's and diabetes--believe it or not. I want to talk about that. The first thing that I think we need to do is just talk about what is homocysteine? And, why is it so damaging to the body?
When you eat dietary protein—proteins are made of building blocks called amino acids—when you eat chicken or whatever protein source, you digest the protein. Essentially, you release the amino acids that make up that protein. They get into your blood stream. One of those amino acids is called methionine. Methionine has a lot of roles in the body itself. It is an important amino acid in DNA protection and muscle production.
Methionine will, inside of the cell, convert into homocysteine. Homocysteine is really just this intermediate amino acid because when you have vitamin B6 on board, homocysteine becomes cysteine. And cysteine is an important amino acid for all kinds of stuff, too. In particular, cysteine will convert eventually down to glutathione, which is the most important antioxidant for your body.
That is kind of the pathway that we like to see when you eat protein. Methionine to homocysteine with vitamin B6. It turns into cysteine and then eventually glutathione. That is a very important pathway. However, if you don't have enough vitamin B6 on board, homocysteine cannot turn into cysteine and that pathway breaks down and homocysteine actually builds up. There is one little side pathway that can happen. Homocysteine can convert back into methionine with vitamin B12. So, vitamin B12 and vitamin B6 are critical to maintaining healthy levels of homocysteine in your body.
But you might ask, "Okay, Dr. Mike, what is the big deal? So what if homocysteine actually builds up? What's the big deal?" There is some evidence, and I presented this to a group of cardiologist a couple of years ago here in south Florida, showing how homocysteine damages what are called "adhesion molecules" that hold together the endothelial lining. That is the inside lining of the arteries.
So, there is some evidence out there that homocysteine is a direct insult—causes a direct damage—to the inside lining of arteries. That includes your heart and your brain and so forth. We want to keep homocysteine levels in a nice optimal range, usually less than about five. That is going to be a nice optimal range if you do check homocysteine on a blood test, which you can. B6 and B12 are critical to keeping that down. A high level of homocysteine is considered a cardiovascular disease risk factor, but there are some other problems with high levels of homocysteine. It is also implicated in vascular dementia.
That is a form of dementia, not Alzheimer's dementia. There are different kinds of dementia. Vascular dementia is usually where you just have repeated small strokes and homocysteine seems to play a role in that.
In a study published in 2014, 64 people with vascular cognitive impairment—like mini strokes—but they didn't really have dementia, they were studied. After only one year, patients with high homocysteine in that group showed a 4.2 fold increase rate of getting dementia down the line. Here you have a group of patients with multiple little strokes and you can actually see that on a CAT scan.
They are able to do all of the cognitive tests, so they don't have dementia yet, but if homocysteine creeps up, there is a 4.2 increase risk of developing a vascular dementia down the line. As a matter of fact, the authors of that study said "Patients with vascular cognitive impairment should receive vigorous controls of high homocysteine level." The journal that came from, this was a Chinese study, I cannot pronounce the journal.
It was a peer-reviewed Chinese journal from 2014. In another 2014 study, they looked at people with high homocysteine in uric acid and find a startling 10.5 fold greater risk for vascular dementia. So, when homocysteine is high and uric acid are high, you're talking about a 10.5 increase risk of vascular dementia. That's huge.
These are the types of numbers that we can't allow conventional doctors to just ignore. That is just amazing that homocysteine, and, in this case, coupled with uric acid, can increase vascular dementia risk that much. That came from the Journal of Neurological Science, 2014. There are many other studies that actually show that link between high homocysteine and vascular dementia. There was a 2013 study that found patients with vascular dementia exhibited particularly elevated levels of plasma total homocysteine. Just confirming some of these other studies.
As a matter of fact, if you go to one of my favorite sites—I've talked about it before—PubMed.com has all of the research studies you want. You can just type in different search terms. You don't have to be a doctor to do all this. If you enter "homocysteine and vascular dementia" you'll pull up 240 published studies dating all the way back to 1992. There is a lot of credible evidence linking excess homocysteine to vascular dementia, not just heart disease. Another type of dementia is, of course, Alzheimer's dementia.
One theory is that what happens in Alzheimer's dementia is capillary blood flow—capillaries are the smaller vessels that actually feed into the tissues—that blood flow is impaired as a result of damage to the inside lining, the endothelial lining, and that is caused by excess homocysteine.
Remember, I mentioned before—homocysteine can directly damage those cells, those adhesion molecules that hold those endothelial cells together.Once that you have that kind of damage, beta amyloid plaques appear in these blood flow deprived areas of the brain because the capillaries just aren't working. They are kind of leaking.
The result, in many cases, is clinically diagnosed Alzheimer's disease. There was a really nice review of this in the British Medical Journal of Public Health, 2014. This was a systematic review of published studies starting in 1990 and extending to 2012 and they found that high homocysteine increased Alzheimer's risk by almost two-fold, whereas, physical activity and Omega3 fatty acids had a protective effect. That is homocysteine and Alzheimer's disease.
A 2013 review looked at the effects of lowering homocysteine for the purpose of protecting against mild cognitive impairment and Alzheimer's disease based on findings from several previous studies. These researchers concluded that "Treating patients with B vitamins could delay or prevent cognitive decline and Alzheimer's disease". Now, I'm not saying B vitamins are a treatment for Alzheimer's. Alzheimer's has many causes. It is multi-factorial. I did a whole review of that on my show once.
But, it looks like I need to add to that there could be an issue with high homocysteine in Alzheimer's patients and B vitamins could play a role in offering some protection. This one was interesting to me: Homocysteine can make diabetic complications worse. This was some new information from the C.D.C. "Eighty-six million Americans suffer from pre-diabetes." That is kind of a blood sugar level 102-125 milligrams per deciliter. It is not quite full blown diabetes yet.
What they found is if you fall in that range and you have high homocysteine, you are at a significant increase risk for developing full-blown diabetes down the line. So, lowering homocysteine is very important to somebody with pre-diabetes. Maybe just B6 and B12 would be a good way to protect from full-blown diabetes.
Get your homocysteine levels checked, make sure it is less than 5. If not, get on some B vitamins. Pretty simple.
This is Healthy Talk on RadioMD. I'm Dr. Mike. Stay well.
RadioMD Presents:Healthy Talk | Original Air Date: May 14, 2015
Host: Michael Smith, MD
Healthy Talk with Dr. Michael Smith, M.D. And now here's the country doctor with a city education, Dr. Mike.
DR MIKE: So, I want to talk about homocysteine. Specifically, I want to talk about some newly identified risks of having too much homocysteine in your body. I think in the medical community most doctors accept now homocysteine or high levels of homocysteine as a risk factor for heart disease.
But new research is showing that it can also impact dementia, Alzheimer's and diabetes--believe it or not. I want to talk about that. The first thing that I think we need to do is just talk about what is homocysteine? And, why is it so damaging to the body?
When you eat dietary protein—proteins are made of building blocks called amino acids—when you eat chicken or whatever protein source, you digest the protein. Essentially, you release the amino acids that make up that protein. They get into your blood stream. One of those amino acids is called methionine. Methionine has a lot of roles in the body itself. It is an important amino acid in DNA protection and muscle production.
Methionine will, inside of the cell, convert into homocysteine. Homocysteine is really just this intermediate amino acid because when you have vitamin B6 on board, homocysteine becomes cysteine. And cysteine is an important amino acid for all kinds of stuff, too. In particular, cysteine will convert eventually down to glutathione, which is the most important antioxidant for your body.
That is kind of the pathway that we like to see when you eat protein. Methionine to homocysteine with vitamin B6. It turns into cysteine and then eventually glutathione. That is a very important pathway. However, if you don't have enough vitamin B6 on board, homocysteine cannot turn into cysteine and that pathway breaks down and homocysteine actually builds up. There is one little side pathway that can happen. Homocysteine can convert back into methionine with vitamin B12. So, vitamin B12 and vitamin B6 are critical to maintaining healthy levels of homocysteine in your body.
But you might ask, "Okay, Dr. Mike, what is the big deal? So what if homocysteine actually builds up? What's the big deal?" There is some evidence, and I presented this to a group of cardiologist a couple of years ago here in south Florida, showing how homocysteine damages what are called "adhesion molecules" that hold together the endothelial lining. That is the inside lining of the arteries.
So, there is some evidence out there that homocysteine is a direct insult—causes a direct damage—to the inside lining of arteries. That includes your heart and your brain and so forth. We want to keep homocysteine levels in a nice optimal range, usually less than about five. That is going to be a nice optimal range if you do check homocysteine on a blood test, which you can. B6 and B12 are critical to keeping that down. A high level of homocysteine is considered a cardiovascular disease risk factor, but there are some other problems with high levels of homocysteine. It is also implicated in vascular dementia.
That is a form of dementia, not Alzheimer's dementia. There are different kinds of dementia. Vascular dementia is usually where you just have repeated small strokes and homocysteine seems to play a role in that.
In a study published in 2014, 64 people with vascular cognitive impairment—like mini strokes—but they didn't really have dementia, they were studied. After only one year, patients with high homocysteine in that group showed a 4.2 fold increase rate of getting dementia down the line. Here you have a group of patients with multiple little strokes and you can actually see that on a CAT scan.
They are able to do all of the cognitive tests, so they don't have dementia yet, but if homocysteine creeps up, there is a 4.2 increase risk of developing a vascular dementia down the line. As a matter of fact, the authors of that study said "Patients with vascular cognitive impairment should receive vigorous controls of high homocysteine level." The journal that came from, this was a Chinese study, I cannot pronounce the journal.
It was a peer-reviewed Chinese journal from 2014. In another 2014 study, they looked at people with high homocysteine in uric acid and find a startling 10.5 fold greater risk for vascular dementia. So, when homocysteine is high and uric acid are high, you're talking about a 10.5 increase risk of vascular dementia. That's huge.
These are the types of numbers that we can't allow conventional doctors to just ignore. That is just amazing that homocysteine, and, in this case, coupled with uric acid, can increase vascular dementia risk that much. That came from the Journal of Neurological Science, 2014. There are many other studies that actually show that link between high homocysteine and vascular dementia. There was a 2013 study that found patients with vascular dementia exhibited particularly elevated levels of plasma total homocysteine. Just confirming some of these other studies.
As a matter of fact, if you go to one of my favorite sites—I've talked about it before—PubMed.com has all of the research studies you want. You can just type in different search terms. You don't have to be a doctor to do all this. If you enter "homocysteine and vascular dementia" you'll pull up 240 published studies dating all the way back to 1992. There is a lot of credible evidence linking excess homocysteine to vascular dementia, not just heart disease. Another type of dementia is, of course, Alzheimer's dementia.
One theory is that what happens in Alzheimer's dementia is capillary blood flow—capillaries are the smaller vessels that actually feed into the tissues—that blood flow is impaired as a result of damage to the inside lining, the endothelial lining, and that is caused by excess homocysteine.
Remember, I mentioned before—homocysteine can directly damage those cells, those adhesion molecules that hold those endothelial cells together.Once that you have that kind of damage, beta amyloid plaques appear in these blood flow deprived areas of the brain because the capillaries just aren't working. They are kind of leaking.
The result, in many cases, is clinically diagnosed Alzheimer's disease. There was a really nice review of this in the British Medical Journal of Public Health, 2014. This was a systematic review of published studies starting in 1990 and extending to 2012 and they found that high homocysteine increased Alzheimer's risk by almost two-fold, whereas, physical activity and Omega3 fatty acids had a protective effect. That is homocysteine and Alzheimer's disease.
A 2013 review looked at the effects of lowering homocysteine for the purpose of protecting against mild cognitive impairment and Alzheimer's disease based on findings from several previous studies. These researchers concluded that "Treating patients with B vitamins could delay or prevent cognitive decline and Alzheimer's disease". Now, I'm not saying B vitamins are a treatment for Alzheimer's. Alzheimer's has many causes. It is multi-factorial. I did a whole review of that on my show once.
But, it looks like I need to add to that there could be an issue with high homocysteine in Alzheimer's patients and B vitamins could play a role in offering some protection. This one was interesting to me: Homocysteine can make diabetic complications worse. This was some new information from the C.D.C. "Eighty-six million Americans suffer from pre-diabetes." That is kind of a blood sugar level 102-125 milligrams per deciliter. It is not quite full blown diabetes yet.
What they found is if you fall in that range and you have high homocysteine, you are at a significant increase risk for developing full-blown diabetes down the line. So, lowering homocysteine is very important to somebody with pre-diabetes. Maybe just B6 and B12 would be a good way to protect from full-blown diabetes.
Get your homocysteine levels checked, make sure it is less than 5. If not, get on some B vitamins. Pretty simple.
This is Healthy Talk on RadioMD. I'm Dr. Mike. Stay well.