Jennifer Jackson asked:
My friend and I were having a discussion the other night and we wondered if there’s any truth in that common statement that alcohol causes brain cell death what the measurable effect is. Her partner also said that spicy food also kills brain cells, we wonder if there is any truth in that at all. We thought you guys would be the best people to ask!
Chris - I can deal with the spicy one straight away because in fact, that’s a myth and there’s evidence that people who eat a lot of spicy food have lower rates of Alzheimer's disease than people who don't eat spicy food. This is because turmeric, the orange stuff which, when you get a bit drunk in the curry house and spill your curry down your shirt (which is always white for some reason when this happens), is the stuff that stains. Turmeric has actually got anti-inflammatory and anti-oxidant qualities. It seems to cut down the production in the brain of a chemical called beta amyloid and beta amyloid is the stuff that makes Alzheimer's disease happen. It builds up and forms plaques in the brain that damage nerve cells. So if you eat lots of turmeric, it seems to reduce the risk of that happening. So spicy food is good for your brain.
That’s that one done. Booze – booze is more difficult. The evidence is, if you were to incubate nerve cells in a solution of alcohol, they would die. So alcohol is a toxin. Thankfully, the body is really well set up to deal with it metabolically. The liver handles alcohol extremely well and only a tiny proportion of the alcohol we drink actually gets into circulation because the liver sees all of the blood that comes from the digestive tract before it goes anywhere near the rest of your body, and the liver therefore deals with the booze before it goes systemically around your body and into your brain. But a small amount of alcohol does go into the brain and when it gets there, the reason it makes us behave the way it does - and we all know what the effects are - at least in modest doses, is that alcohol increases the activity of one of the brain’s inhibitory nerve transmitter chemicals. This is called GABA. This damps down the activity of nerve cells. So unlike certain drugs like ecstasy which can in fact make nerve cells more active and damage them, alcohol damps down the activity of nerve cells and therefore it makes them less vulnerable to damage.
Jennifer - So they might live longer?
Chris - Well, they may do. The evidence is, small doses of alcohol probably don't harm neurons and the body’s pretty well set up to cope with it anyway. If you look at people who have spent their whole life drinking modest amounts of alcohol, there’s evidence that actually their intellect may be preserved better than teetotalers. That’s not saying, now, prescribe yourself daily alcohol intake to live a long time and have good brain function into old age. That’s not what we’re saying. But what we are saying is that epidemiologically, if you look at populations, the evidence is that it doesn’t do any harm. There’s no evidence for significant harm in those people. If you also look at people who are chronic alcoholics, unless they get a condition called Wernicke–Korsakoff's psychosis – which is where they run out of a vitamin called B1 (thiamine) which is very destructive to nerve cells – they don't actually have huge damage to the nervous system unless they are very, very, very heavy drinkers for a very long time. So therefore, the evidence is that alcohol is probably okay in modest doses and most of the injuries and most of the damage to the brain happens when people get drunk and fall over and hit their head, or get into fights. That’s actually the reason why head injuries happen with alcohol and why brain damage probably occurs.
Jennifer Jackson asked the Naked Scientists: Hi Chris and the Naked Scientists I discovered your programme a few weeks ago while searching in desperation for some good scientific media reporting. Your programme is a really excellent example of that, and I've been listening avidly to your back catalogue and recommending your program to friends and colleagues ever since. My good friend Gaby in New Zealand has become a fan too and we were wondering if there is any truth in the common statement that alcohol causes brain cell death, what the measurable effect is, and whether eating spicy food also does this, as we've heard claims along these lines. Very best of luck and success in your work, Jen and Gaby What do you think? Jennifer Jackson , Sat, 8th May 2010
In a sense yes, alcohol can kill brain cells. Being drunk is your brain's reaction to being suffocated. Alcohol replaces oxygen and produces the intoxication. Enough of it can kill you, in essence, killing a lot of brain cells. aaron28, Sat, 8th May 2010
Alcohol doesn't replace oxygen. Bored chemist, Sun, 9th May 2010
Alcohol (ethanol) is a toxic chemical, but the body is metabolically well-equipped to deal with it, with the liver accounting for the majority of this detoxification. This organ is the first port of call for blood draining from the digestive tract before it enters the systemic circulation.