Memory loss: a pill to save your mind?

The big question was: does high homocysteine cause Alzheimer’s, or is it the result of the disease?

July 13, 2012 | By:

Much mainstream opinion is that there is nothing you can do to slow memory loss. But a little-talked-about trial says high-dose B vitamins plus an antioxidant called NAC may protect you. By Jerome Burne

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Brain drain: an antioxidant called glutathione may be the crucial link in preventing cognitive impairment

Being worried about the declining abilities of your brain comes with the territory when you hit the high five-oh. It could be triggered by leaving your house with the car keys rather than house keys, or momentarily forgetting the name of your child’s best friend.

So what can you do about it?

If you trust your doctor and most mainstream medical opinion the brutal answer is: nothing. Of course there are soothing nostrums about keeping your mind active, exercising, eating well – especially fish, fruit and vegetables – but none are backed up by tough-minded randomised controlled trials of the sort that supposedly underpins modern medical practice.

But that is not strictly true. There is a plausible option supported by a properly done trial, but it’s not talked about in polite medical circles because it involves taking very high doses of B vitamins. I’ve written about B vitamins and Alzheimer’s here before, and now there is a new twist to the story.

The homocysteine story so far

To quickly recap: for years there have been reports that people with dementia have a high level of an amino acid in their blood called homocysteine. Essentially, it is a halfway house in a biochemical chain starting with methionine, which we get from our diet, that makes the compounds vital for a healthy brain.


Too much homocysteine is a sign that it is not being broken down to make the good stuff. A large amount may also damage cells in its own right. The big question was: does high homocysteine cause Alzheimer’s, or is it the result of the disease?

The only way to find the answer was with a placebo-controlled trial. But setting one up had to overcome two major hurdles. First was the general medical scepticism about vitamins, especially in high doses, because only B vitamins lower homocysteine.

Secondly, because vitamins are unpatentable, there was zero drug company interest in running trials. However, in 2010, a determined Oxford researcher, Professor David Smith, published the results of a trial that ticked all the boxes.

More than 200 people, followed for two years, got either the vitamins or a placebo. The amount of brain shrinkage was measured with two scans.

The results showed that those getting vitamins who had the highest homocysteine level saw their shrinkage rate cut by up to 50 per cent. (For more details see Food for the Brain: dementia.)

The news drove up sales of products high in B vitamins, but getting them all in a single pill proved tricky, which is where a new character in the story comes in.

Then came the science…

Professor Andrew McCaddon is a Welsh GP who heads an American company that has been selling a pill containing all the B vitamins and a powerful antioxidant for several years in the US. It has just launched it in the UK.

Professor McCaddon has been involved in the homocysteine story for more than 20 years. As a trainee GP working at the Dementia Research Centre in London, he investigated a family of 12, half of whom had developed dementia early. He found that all of those with the disease had very low levels of vitamin B12.

Later he was the first to find that elderly patients with Alzheimer’s had much higher levels of homocysteine, when compared with healthy ones.

Several years ago, he showed that patients with Alzheimer’s have significantly raised levels of homocysteine. Next, he reported that the more homocysteine they had, the worse their mental performance.

NAC: the added ingredient

The discoveries kept coming. A couple of years ago he reported that the worse their ‘cognitive impairment’, the less they had of an antioxidant called glutathione, which is involved in DNA repair and making proteins.

This makes a lot of sense, because glutathione is made from homocysteine – and if your homocysteine is not being used up, glutathione production will be down. Just to complete the circle, glutathione is vital for making a major chemical messenger in the brain called acetylcholine, which Alzheimer’s patients are famously short of.

So the extra ingredient in Professor McCaddon’ s formula, called Betrinac, is an antioxidant known as NAC, which increases the amount of glutathione. NAC is found is a range of foods including peppers and asparagus, and is already used to treat paracetamol poisoning and to break up the mucus in the lungs of cystic fibrosis patients.

There is good reason, then, to suspect that it might work better than the B vitamins alone. But of course that hasn’t been properly tested and no one has repeated Dr Smith’s breakthrough trial either. So do you wait for all the evidence to come in, which might be never, or do you give it a try? Your call.