Science Interviews


Tue, 19th Jan 2016

Detoxing debunked

Dr Kat Arney, The Naked Scientists

Listen Now    Download as mp3 from the show The Hidden World of Hibernation

Kat is settling down with some herbal tea and a stick of celery to bust aGreen Smoothie common mythconception at this time of the year…

Kat - I’m sure that your Christmas and new year was just like mine - a model of restraint, packed full of healthy steamed veg, lean protein, plenty of water and lots of bracing exercise… Oh, who am I kidding? I’ve eaten and drunk so much that if you cut me I’d bleed port and gravy.

Luckily the internet and other media are full of people offering - or rather selling - advice and products to help us all ‘detox’ after the festive season. The shelves of health food shops and pharmacies groan with the post-Christmas bulge of detox stuff, from pills, teabags, smoothies and potions to shampoos, colour-changing footpads, and even hair straighteners. But what exactly is ‘detoxing’, and does it actually do anything?

Well, for a start, there is a valid medical definition of ‘detoxing’ - it’s one that involves being in hospital after an acute episode of drug, alcohol or other type of poisoning and having urgent medical treatment. Not sipping on a carrot smoothie because you feel a bit run-down and hungover after the party season.

Many so-called ‘detox’ regimes involve things like fasting for short periods of time, eating only fruit and veg or other limited diets, cutting out certain foods like wheat, dairy, caffeine and alcohol, and taking certain pills and potions to help ‘flush out’ the ‘toxins’ from your body. I guess it all sounds kind of sciencey, but the detox peddlers can’t actually provide any solid evidence at all for what these mysterious ‘toxins’ might actually be, or how their regimes and products help to get rid of them.

Furthermore, severe low-calorie ‘detox’ diets may help you lose weight in the very short term - which is mostly water, due to your body having to metabolise water-storing energy-rich molecules like glycogen to keep you alive. Unlike a slower, steadier calorie-controlled weight loss plan, crash detox diets are likely to leave you feeling sick, headachey, dehydrated, weak and cranky. It’s not the ‘toxins leaving your body’ - you’re starving yourself.

The key thing to know is this: your body does an amazing job of detoxifying itself, all day, every day. If your body really accumulated large amounts of what the scientific world classes as toxins, then you’d start to feel very ill very fast and need urgent medical attention.

The liver does a sterling job of getting rid of toxic substances without the need for a helping hand - it’s packed full of enzymes that convert nasty chemicals into less harmful ones, and then pass them on into the kidneys or gut to be peed and pooped out. Your kidneys are also hard at work sifting out nasty stuff from the bloodstream and sending it to be flushed down the loo. And your lymphatic system - that’s your lymph vessels, lymph nodes and spleen - are quite happy getting on with the job of filtering out foreign muck like bacteria and viruses, without the need for ‘stimulation’ from unproven detox products.

The detox industry also seems to have a woeful lack of actual chemistry knowledge. For example, fruits like apples contain very small amounts of the chemical formaldehyde, while veg such as broccoli contain traces of cyanide, both of which are toxic in high doses. So why don’t the detox fans class these as toxins, eh? Incidentally, this is why it’s also a good reason not to go overboard with the superfood smoothies, as you could be taking in much higher amounts of naturally-occurring plant-based chemicals than you’d normally need, with unknown effects.

The dose makes the poison of course, but all the foods we eat contain a wide range of all kinds of chemicals that can potentially harm us in high enough doses, whether that’s a chunky chocolate bar from the corner shop or the freshest organic apple straight from the field.

And in some cases herbal detox products may contain chemicals that act as drugs on the body, yet these aren’t tested or regulated in the same way that equivalent pharmaceutical products would be, and also have a risk of unwanted interactions with any conventional medications that a person might be taking.

So, what should you do if, like me, you’ve consumed so much your bloodstream is now 90 per cent gin or you feel like you’ve actually turned into a pig in a blanket after eating so many?

According to real science - from clinically-trained registered dietitians rather than internet nutritionists - if you’ve overindulged over the festive season and want to get back on a healthier track, the best things to do are the usual boring stuff we all know about, deep down: Cut back on the booze and cakes, drink enough water to get you hydrated, get some physical activity in your life, eat a healthy balanced diet with lots of fruit, veg, fibre and some lean protein, and get plenty of sleep.

If you manage to do that, you’ll more than likely lose weight and feel a lot better without any need for fancy, expensive detox products. Now, if only I could turn that into a multi-million selling diet book, I’d make a fortune!




Subscribe Free

Related Content


Make a comment

See the whole discussion | Make a comment

Not working please enable javascript
Powered by UKfast
Genetics Society