Who is Dr Kilmer McCully and why do we need to know his name?

Jan 31, 2024 | Male B12 deficiency, Mental health, Misdiagnosis, Raising awareness | 22 comments

If a student of architecture was never taught about foundations of buildings during their eight years of training it would be considered sheer lunacy. But the foundation of human health – nutrition – is barely touched upon in medical education in the western world. Despite this being an absolutely ludicrous state of affairs, the architects of medical training don’t appear to see or even care about this gaping hole in knowledge. What you’ll read here is a story of the silencing of genius and the burying of essential health information which was discovered over 50 years ago…

Anyone who has looked at B12 deficiency in some depth will know the word homocysteine and will understand its role in health. We know about it because of Dr Kilmer McCully’s pioneering 1969 research.

Dr Kilmer McCully

To introduce those of you who are new to his name, I add the following text from an interview of Dr McCully with Gloria Bucco taken from: The July issue of Nutrition Science News

Thirty years ago, Kilmer McCully, M.D., discovered that cholesterol and clogged arteries are not the causes but rather the symptoms of heart disease. McCully’s pioneering 1969 theory that linked homocysteine— an amino acid that accumulates in the blood—and heart disease was not embraced by the medical community. In fact, he was banished from Harvard University and Massachusetts General Hospital and denied a new position for more than two years because of his research.

Dr McCully’s story is one of ostracism and loss because he discovered something so elegantly lifesaving with an inexpensive, nutrition solution. As with all discoveries based in non patentable treatments such as vitamins and minerals it would turn the flowing tap of dirty money off and the powers that shouldn’t be, don’t like this at all.

You can read more about the story of Dr McCully’s early career and its interruption from this New York Times article – The rise and fall of Kilmer McCully Aug 10th 1997 by Michelle Stacey. She details how his research begins in the excerpt below…

… After graduating from Harvard College and Harvard Medical School, he embarked on a series of research fellowships. In the mid-60’s, as a young pathology instructor at Harvard, McCully made the scientific observation that would define his career. He became intrigued by two different cases of children with homocystinuria, a rare genetic disease in which the levels of homocysteine in the blood are unnaturally high. In both cases, the cause of death was severe arteriosclerosis, a narrowing and loss of elasticity in arteries that is normally seen only in the elderly. By re-examining the autopsy tissues of both children and drawing on previous animal research, McCully emerged with two linked and provocative suggestions: perhaps homocysteine directly damages the cells and tissues of the arteries, in much the way that cholesterol is thought to do, and perhaps that damage occurs not just in these rare genetic cases but in the population at large, in any people with elevated homocysteine levels.

He soon expanded his theory to include a probable cause of elevated levels of homocysteine: a deficiency of vitamins B6, B12 and *folic acid. When these vitamins were administered to animals with high homocysteine levels, those levels plummeted, often within hours. Once McCully started extrapolating from his cellular-tissue and animal studies to the human situation, he says, ”it all began to fit together.”

Homocysteine in the body derives from methionine, an essential amino acid present in large amounts in protein from animal sources like meat, eggs and milk. If there are adequate levels of vitamins B6, B12 and folic acid* in the body, the homocysteine is broken down into harmless waste products or protein building blocks. But if there’s a deficiency of those vitamins, the homocysteine begins its ravages on the blood vessels.

* I have asterisked folic acid above because there’s more to folate or B9 nowadays.

Treatment of high homocysteine

Dr McCully naturally advocates that a good diet is key to accessing the necessary B vitamins but as we know diet cannot improve B12 levels if you cannot absorb B12 from food and if you have genetic problems with folate.

In answer to the question – So how can we prevent homocysteine from reaching these dangerous levels? Asked by Gloria Bucco taken from: The July issue of Nutrition Science News, Dr Mc Cully states:

I’m a strong believer in dietary improvement, and I believe the high incidence of arteriosclerosis and heart disease in our population can be traced to diet. This new theory allows us to understand what we can do to improve our diet.

Both folic acid and vitamin B6 are chemically unstable vitamins that are often lost during food processing. It’s been shown that the population is not getting enough of these vitamins, and this in turn leads to elevated homocysteine levels.

The way to get these vitamins is to eat fresh whole foods—fresh vegetables, fruits, meat, fish and dairy products. We should also eliminate foods that contain highly processed ingredients such as white flour, sugar and oils. If we do this, we can vastly improve the quality of our diet and increase the intake of these important vitamins.

If a person has been eating a nutritionally depleted diet his whole life, it may be difficult to correct this abnormality just by improving diet. Supplemental vitamins may also be needed. Anyone who has a high risk for heart disease, either from family history or poor nutritional background, or who has early signs of heart disease, probably should take vitamin supplements to control homocysteine levels and stop the arteriosclerotic process.

With the above in mind and understanding that you may not have known Dr McCully’s name previous to visiting this page, we should ask….

What’s the prevalence of cardiovascular events?
Don’t we all know of someone who has suffered a stroke or a heart attack? Ever wondered why these conditions are so common place? Why is everyone who survives these events given statins and blood pressure tablets rather than exploring vitamin B12, B9 and B6?

These conditions have been listed as the most common cause of death by the WHO for decades…

The world’s biggest killer is ischaemic heart disease, responsible for 16% of the world’s total deaths. Since 2000, the largest increase in deaths has been for this disease, rising by more than 2 million to 8.9 million deaths in 2019. Stroke and chronic obstructive pulmonary disease are the 2nd and 3rd leading causes of death, responsible for approximately 11% and 6% of total deaths respectively.

And from the same source:

In 2019, Alzheimer’s disease and other forms of dementia ranked as the 7th leading cause of death. Women are disproportionately affected. Globally, 65% of deaths from Alzheimer’s and other forms of dementia are women.

We know that homocysteine has a role in cognitive decline too. We also know that these conditions may also be misdiagnoses of B12 deficiency.

In the UK from the ONS

The leading cause of death in 2022 was dementia and Alzheimers disease, which accounted for a higher proportion of deaths in females than in males.

Whilst I’m aware that there are other potential causes for the conditions above, we have a major piece of the jigsaw deliberately being kept out of sight. The correct treatment and even cure for many with these conditions detailed above has been shelved.

What we know is, that despite the genius discovery by Dr McCully over five decades ago,  and the thousands of research papers since then, the link with homocysteine and cardiovascular health has not reached your GP Practice and has been kept from you, the patient and from health professionals the world over…It has also been kept from you, the charity patron.

I can clearly remember the day in 2012 where I asked my GP about homocysteine – his reply, ‘I don’t even know what that word means’ whilst chucking printed research I’d handed over, straight into the bin behind his desk. This was not and still is not, unusual behaviour. Previous to this encounter, we’d got on well. My doctor and all others, have not been educated properly, if at all about B12 deficiency and the fact that homocysteine may be an unknown entity to them is an absolute disgrace.

One of Dr McCully’s books, The Heart Revolution, (published in 1999) leads with the strap line: The extraordinary discovery that finally laid the cholesterol myth to rest and put good food back on the table.

From the Heart Revolution…

More than 30 years ago, a young Harvard pathologist offered the medical community a theory for the cause of one of today’s biggest killers-heart disease. It is called the Homocysteine Theory and is the medical breakthrough that inspired Andrew Weil to label Dr. McCully as “a visionary medical pioneer well ahead of his time”. This discovery has the potential to save millions, yet ironically destroyed Dr. McCully’s medical career. Homocysteine, a byproduct of metabolism, has been discovered to be a better risk indicator of heart disease than high cholesterol. 

If only that strap line were now true the world over and the cholesterol myth wasn’t still being perpetuated. If only every medical professional had this book as part of a medical training module and on an essential reading list?

Thomas N. James, a cardiologist and president of the University of Texas Medical Branch who was also the president of the American Heart Association in 1979 and ’80, is even harsher. ”It was worse than that you couldn’t get ideas funded that went in other directions than cholesterol,” he says. ”You were intentionally discouraged from pursuing alternative questions. I’ve never dealt with a subject in my life that elicited such an immediate hostile response.”

Even as recently as last year, Alan Garber, an associate professor of medicine at Stanford University, was stunned after he and a colleague, Warren Browner, proposed that healthy young men and women need not be screened for cholesterol, since treatment at young ages has not been shown to be useful or cost effective. ”The American Heart Association and the National Heart, Lung and Blood Institute issued press releases and had a big campaign to discredit our work,” Garber says.

I urge you to read the full article, there are more like those above to chew on.

I’m writing this blog in the hope that people who are currently caring for those affected by these preventable and devastating life changing events can access information and treatment which will aid their recovery if implemented by their health care professionals.

I appreciate that I am writing from a UK perspective and that your home country may do things far better than we do here.

So, what does the NHS tell us about homocysteine?

The NHS and stroke

If you have a stroke, the diagnosis page on the NHS website doesn’t make any mention of homocysteine, but of course they mention testing your cholesterol levels and sugar levels. They might also conduct a Brain scan, CT Scan, MRI Scan, swallow tests, carotid ultrasound or echocardiogram, but zero testing for B vitamin levels or homocysteine!

Let’s have a look at the NHS causes page for stroke. No, not one mention of homocysteine or B vitamins here….

Ischaemic stroke causes listed:

And now what about the NHS Treatment page? This is where you may be offered all manner of surgeries or drugs such as the ubiquitous statins, blood pressure tablets, ‘clot busters’, anticoagulants, and aspirin.

The only remote mention of nutrition is right at the bottom of the page stating under the heading: Supportive treatments:

  • nutritional supplements if you’re malnourished

Searching homocysteine on the entire NHS website today brings up no result for homocysteine, but they do have a page on homocystinuria which is the inherited disease that Dr McCully researched to discover his findings about homocysteine.

The following paper published online in 2020,  Role of vitamin B12 deficiency in ischemic stroke risk and outcome States:

Our survey of the literature has identified that there is a gap in the understanding of the mechanisms through which a vitamin B12 deficiency leads to an increased risk of stroke and outcome. A vitamin B12 deficiency can increase homocysteine levels, which are a well-established risk factor for ischemic stroke.

Well – established BUT still, no one who needs to, tells you about it!

The NHS and heart attack

NHS Causes of Heart attack page states…

Your risk of developing CHD (coronary heart disease) is increased by:

B12 deficiency and high homocysteine is also a major concern in cognitive decline as you can see from this paper Homocysteine and dementia An International Consensus statement from the Journal of Alzheimer’s disease 2018.

NHS Dementia symptoms/diagnosis/tests page makes no mention of homocysteine but does mention B12 and folate in this section:

Blood tests to check for other conditions

Your GP will arrange for blood tests to help exclude other causes of symptoms that can be confused with dementia.

In most cases, these blood tests will check:

  • liver function
  • kidney function
  • thyroid function
  • HbA1c (to check for diabetes)
  • vitamin B12 and folate levels

If your doctor thinks you may have an infection, they may also ask you to do a urine test or other investigations.

So as you can see, the NHS are going all out here to tell you about homocysteine, literally breaking their backs, in a, lets put that in a cupboard inside a strong room and build a wall in front of it, kind of way….

Money, because it’s always about the money

Over fifty years on from Dr McCully’s research and because there’s no financial incentive in the medical and pharmaceutical field to prevent vascular disease properly and effectively it simply doesn’t happen. So until that changes, we, need to keep on shouting about homocysteine and the three legged stool of B12 – cobalamin, B9 – folate and B6 – pyridoxine until this hidden penny drops.

There is so now much research built upon Dr McCully’s original findings. Over 29,006 results on PubMed alone under homocysteine, but it might as well be in the bin for all the influence it currently has with your GP, the NHS and charities.

These UK Charities could and should be up to date and be advising visitors to their sites of good research into homocysteine but…

If you search for homocysteine on the pages of the following British charities as I write this today, you will draw an almost complete blank:

The British Heart Foundation don’t talk about homocysteine at all, they just parrot the NHS lists above despite all their years of funding ‘research’, nothing appears to have reached them about the key cause of heart attack. This charity also list all manner of tests but no homocysteine listed here either.

When searching the term ‘Homocysteine’, on their site, I was advised : There are no results for homocysteine. Please try checking the spelling or try a different search term. They do however, give you five long pages on cholesterol. Funny that.

The Stroke association –  Finds nothing

Dementia UK – Finds nothing

Alzheimer’s Society UK does best, but only comes up with this wishy washy page titled: Omega-3 may boost vitamin B  – This page tells the reader nothing much, lumps all B vitamins together and gives nowhere for the reader to research more. They state:

Evidence for the role of vitamin B in dementia is not clear. B vitamins are responsible for lowering homocysteine, a chemical often found at high levels in the blood of people with dementia, but some clinical trials have shown that taking B vitamins has no effect on brain function, despite their effect on homocysteine.

They don’t bother to link to the Alzheimer’s Journal research article they quote from. It seems they are not too fussed about exploring homocysteine further if this is the best they can do. They do however add links to ‘about 20’ articles or research when you search the term ‘cholesterol’.

These charities are all rich organisations, they regularly harangue people for their hard earned cash for ‘research’. Some of them ask you to will your homes to them.You may have had your heart strings tugged in the street to give a monthly donation.You may have asked that funeral donations be given to them. You have done this because someone you love has the condition or has died with the condition that they promise to be ‘researching’ a cure for or treatments for…
If you have given these organisations money, and you feel strongly about what is written in this blog, why not hold them to account? Ask them to alert users of their sites to B12 deficiency and high homocysteine since we know that it’s a key factor in these conditions.

Because I’m a helpful soul, I’ve added links to research on PubMed that these charities should be taking a long hard peep at….and then they should be explaining themselves.

Homocysteine and cardiovascular disease  10,488 results

Homocysteine and arteriosclerosis 2,185 results

Homocysteine and coronary heart disease  2,378 results

Homocysteine and stroke 2,037 results

Homocysteine and Ischaemic heart disease 2,520 results 

Homocysteine and dementia 1,234 results

Homocysteine and vascular dementia 367 results

Homocysteine and cognitive impairment  814 results

Homocysteine and Alzheimer’s 1,098 results

The masquerade

The Alzheimer’s Society created this film – Dementia research round up which might be of interest to you, knowing what you know now…
Dr Richard Oakley the Associate Director of Research tells you they are ‘on the cusp of a truly transformative breakthrough’ and he says ‘game changer’ a few times in order to extract more support and funding from you for their ‘research’.

Here’s the government pledge to spend £160 million pounds on dementia research mentioned in the film above…….

The British Heart foundation say they currently support £440 Million pounds of research projects across the UK and have been awarded £100 million of research grants last year to ‘better understand and treat heart and circulatory diseases.’. So these amounts of money are huge. BUT they appear to actively choose to ignore anything to do with homocysteine.

What should we be doing?

I sit here with you at the beginning of 2024 and know that Dr Kilmer McCully’s name and his work is still relatively unknown and that the vast majority of health professionals will not really understand the impact of homocysteine on cardiovascular and brain health.

So, if you or a loved one find yourselves in an ambulance on the way to hospital having had a stroke or heart attack or are experiencing cognitive decline, remember the word HOMOCYSTEINE and say it repeatedly until you or they are tested. Add in B12 and folate and B6 (if you can get the latter done). Treatment of B12 injections should not be delayed, the sooner treatment starts the better. You could use this leaflet to help push the point home.

Make sure you get a copy of the results in your hand. The optimal level for the homocysteine test is said to be around 6 umol/L, but the reference range usually between 0-15 umol/L. Anything over 15 umol/L absolutely needs attention. You may still have to educate your doctor about what it all means. You can help yourself and them with the What to do next page. Point four is key in regard to test results.

Some people who are unfortunate enough to experience conditions arising from high homocysteine may not have accessed testing of vitamin levels prior to being given nutrients via a PEG feeding tube. If testing is carried out following PEG feeding this will skew results so must be taken into account by the lab. An unknowing clinician will be thrown off the scent by skewed results telling you, ‘all levels are normal’.

If you have not experienced these conditions but they are familial, please don’t rush out and buy supplements without doing more research. If you eat animal products and you have symptoms of B12 deficiency then B12 tablets are not going to help and you will need injections, this means it always best to go to your GP and get tested first in case results are skewed by taking oral vitamins.

If you have survived a cardiovascular event, check your results to see if you were ever checked and talk to your GP or consultant about B12 deficiency and homocysteine.

If you are a vegetarian or a vegan then you may be able to absorb B12 in oral form but there are so many causes of B12 deficiency which may affect you too. For example, you  may be taking drugs which inhibit folate and B12 and this means you will not absorb these nutrients well or at all. You will absolutely need B12 injections if you can’t absorb B12 from food.

I’m sure you’ll agree that the current situation must change and I hope you’ll help that change by sharing this information as far and as widely as you can.

If you want to learn more about B12deficiency, please take a look at the courses page.

As always, I love to hear from you, so please leave a comment below.

All the very best,

I’ll leave you with the voice of Dr Kilmer McCully….

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  1. Nicki Davies

    I had a heart attack in 2017, aged 48. Cholesterol was normal.
    I’d been on intensive B12 injections for about a year by then, having been denied proper treatment by my GP, I was sourcing it privately.
    After my heart attack, I asked my cardiologist to test my homocysteine levels, and he laughed and said there was no need, it was a bit like cleaning under the fridge.
    Unfortunately at the time, I didn’t think to say that it’s normal to clean under the fridge when you’ve had an unfortunate infestation of mice!
    I did get it tested privately, and it was about 8, but this was after a year of daily/every other day B12 injections, so I suspect it had been much higher beforehand.
    I contacted the BHF about research into homocysteine and they told me that there was no evidence of a link between homocysteine levels and cardiovascular disease, and at the time, I didn’t have the energy to argue with them.
    There is definitely a wilful ignorance amongst many research bodies!

    • Tracey Witty

      Nicki, thank you for your comment, I’m sad to say I’m not shocked by your cardiologist or by the BHF! It’s a disgrace.

  2. Jane Knowles

    Wow! My late husband had a heart attack in 2007, was given Atorvastatin and a cocktail of other drugs. He was also prescribed metformin for T2 diabetes. In 2018 he required a CABGx4 and suffered a “small but significant stroke a few weeks later. His cognitive abilities were noticeably declining during 2017. In October 2018 he was prescribed B12 injections as is B12 levels were really low. He had loading doses and then 3 monthly injections, he felt they did nothing as he felt lousy when he had the injection and lousy when he needed the next one – to those of us looking on he was a different person for about 6 weeks, he was sharper, more mentally able, better coordinated. His prescription was stopped during the Covid pandemic, he took high dose tablets which did help but were not as effective as the injections.
    In 2021 he suffered another heart attack, followed by a stroke in March 2022. He passed away in November 2022 and his post mortem showed that his arteries were hardened and blocked.
    Homocysteine was never mentioned or checked.

    • Mary

      I’m so not surprised Tracey. I looked into this briefly for a friend whose daughter had a stroke… After being a mod on a huge group you get to see the same things coming up again and again and the TOTAL LACK of knowledge is the biggest disappointment to me.

      Thank you for putting it I to relatable language. I will share too.

      • Tracey Witty

        You are very kind Mary, thank you for sharing!

    • Tracey Witty

      Jane, thank you for taking the time to comment, I am so sorry for your loss. Too many people had B12 injections stopped and have never had them reinstated. It’s heartbreaking that there’s so little understanding of B12 deficiency and homocysteine.

  3. Judy Y

    Wow and wow I am part flabbergasted and angry, Your research is amazing, I am not sure what to write, as I cant believe quite what I have just read. Fifty years ago this come to light, why are medical professionals so arrogant to not keep themselves updated with new discoveries? The people who need to read this are the doctors who decide what new doctors learn. Plus all doctors should be made to go to conferences every few years to take in such research. We have long ago stopped treating doctors as gods, but still too often they consider themselves as such

    • Tracey Witty

      Thank you Judy, It is an absolute shocker that this info hasn’t reached the NHS and our health professionals. We just have to keep in sharing info!

  4. Janet Crosley

    How incredibly interesting.
    Thankyou very much.

    I have Pernicious Anaemia, and find the ignorance of the medical fraternity appalling. I have to supply meds and inject myself, My GP approves. He is the only one in my 50yrs since diagnosis that understands about the condition.

    • Tracey Witty

      Thank you Janet, what a shame your GP feels he can’t supply the B12 you need, when you need it.

  5. Hilary Thompson

    Brilliant article. Many thanks.

    • Sheena

      Wow! What an eye opener! Thanks for this Tracey…. extremely informative.

      • Tracey Witty

        My Pleasure Sheena!

    • Tracey Witty

      Thank you Hilary!

  6. Suzy

    This is very interesting, thank you for all you do and sharing this information. 🙂

    • Tracey Witty

      Thank you Suzy!

  7. Ann Wright

    Again an excellent article full of necessary information how do we get it across to GPs who are sadly lacking in this knowledge and very little interest in researching. Maybe it needs to be sent to the editors of medical journals. I suppose most of these publications probably end up in the waste bin as many doctors feel they know it all anyway .

    • Tracey Witty

      We can only hope someone takes away the bins Ann!

  8. Barbara Bradbury

    Thank you. Most enlightening, Tracey. I have passed it in to a friend whose daughter has porphyria.

    I had success with glyderyltrinitrate (nitroglycérine) for nerve pain with Porphyria, trigeminal neuralgia and Raynaud in hands and feet. Used at the First signs of pain in very minute doses, it worked for many years till the delivery method changed.
    I tried to pass this knowledge on, but suspect doctors behind the scenes were unprepared to prescribe this. The guidelines had changed and prescribing stopped, because MEN on hormonal treatment were having heart attacks, said to be due to the glyceryl trinitrate. The method of delivery was awkward and unwieldy. In this day and age of precision, why you would be left to spread a one or so inch of cream into a piece of paper, and slap it onto your skin, beats me.
    I suspect, as nerve pain is very severe, it would be easy to overdose and so lower heart rate too suddenly. When I passed the information on the doctor of the girl with Porphyria, said as her cholesterol was high, it was too dangerous. In my logical way if thinking it would have been corrective not destructive, but I am not a doctor!
    I will leave readers with the task of making connections with your excellent article.

    • Tracey Witty

      Thank you for your valuable comment Barbara!

  9. Eric Dabbs

    Amazing! In the early 1970s I went out with a Belgian, Madeleine, who was a technical assistant in Dr McCully’s lab at Mass General. During those years she shared the feeling of hopelessness in his lab. With declining funding Madeleine returned to her home country so probably never knew of his vindication.

    • Tracey Witty

      Thank you for sharing this information Eric, that must have been really tough for Madeleine, a shocking situation for Dr McCully and his colleagues!


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