Should I wear gloves and a mask when flying? And why do I wake at 3am every night?

OVER the past few months I’ve written in this column about everything from natural pain relievers and how magic mushrooms could herald a treatment for drug-resistant depression, to the waning concentration of minerals in vegetables and ways to boost your IQ.

Your letters have, as ever, been flooding in, so this week I’m going to attempt to answer a few of the most commonly asked questions. Please keep writing, as I love finding out what you, the readers, think.

WE A RE d ue t o g o o n holiday b ut a fter r eading your a rticle o n h ow unhygienic a irports are, I ’m w orried. W ould you r ecommend u sing gloves a nd m asks while t ravelling?

IT’S true that airports and planes are especially easy places to pick up infections. There are lots of people packed together, and about 80 per cent won’t have washed their hands recently, according to studies. If someone has a cold or a flu virus and sneezes on their hands, then touches or wipes those hands on a surface, some of the germs will be transferred. Those viruses can happily survive for many hours on metal or plastic, waiting for a new victim to come along. If you are unlucky enough to touch that same area, the viruses will transfer on to your hands.

Unless you wash your hands, those viruses will get from your hands into your body the next time you touch your nose or rub your eyes.

Wearing gloves probably won’t help because the viruses can survive on most surfaces – so if you touch an infected surface with your glove, then rub your eyes with that same glove, there is still a chance of transmission.

A mask might help if someone sneezes directly into your face, and might protect others from your sneezes, but it won’t save you if you rub your eyes with infected hands, for example.

That’s why it all comes back to good old hand-washing. If you can, clean them after you’ve been through customs, at some point during the flight, and soon after you get off the plane. These are the moments when you are probably most at risk. And try to avoid rubbing your eyes if you can.

I H AVE a lways s lept w ell b ut s uddenly I ’ve f ound m yself waking a t 3 am e very n ight and I ’m u nable t o d rop o ff again. I f eel s o g roggy t hat I’ve h ad t o t ake n aps d uring the d ay. A ny a dvice?

I FEEL enormous sympathy for anyone who suffers from ‘middle of the night waking’ because it’s something I’ve struggled with for many years. Some people find it hard to go to sleep but the most common type of insomnia is this type: waking up in the middle of the night and finding it difficult to nod off again.

If it is any consolation, this pattern of sleeping was common before the invention of electric lighting. In pre-industrial times, people went to bed at about 9pm, woke up in the middle of the night, did some cleaning or had a chat with family members, then went back to bed again. It was so common that people talked about having a first and second sleep.

I have just finished writing a book about sleep, called Fast Asleep, which will be published next month. It is based on lots of self-experimenting and extensive chats with experts.

As well as unpicking some of the mysteries of sleep, it is packed with lots of useful science-based advice that goes beyond the usual ‘keep the bedroom dark and quiet’ tip which, as many discover, is often ineffective.

One thing you could try is so-called stimulus control. If you wake and feel you won’t get back to sleep, then instead of lying there fretting, get out of bed and listen to music or read a fairly boring book in another room. Only go back to bed when you feel you are tired enough to fall asleep.

RECENTLY, I ’ve d iscovered t hat kombucha c an h elp t owards a healthier g ut. I f ind i t s o e asy to d rink, e specially C aptain Kombucha, w hich h as s ome great f lavours. S ome d ays I h ave more t han o ne 4 00ml b ottle. How m any s hould I b e h aving?

I AM also a big fan of kombucha, along with other fermented foods such as sauerkraut. We make both at home and if you want to see how easy it is, I recommend you watch a video of my wife, Dr Clare Bailey, making it at cleverguts.com.

For those unfamiliar with kombucha, it is a form of fermented tea – it has a refreshing, apple-like, slightly sweet and sour taste and a bit of fizz. It contains lots of probiotics, those health-enhancing live bacteria. If you do make it yourself, first you need to purchase a symbiotic culture of bacteria and yeast, or SCOBY for short. The mushroom-like disc is a vital ingredient in the fermentation process. You can buy a SCOBY online, or you could see if someone at cleverguts.com is happy to send you a sample of theirs. In my experience, fermenters are a friendly lot.

If you look after your SCOBY, they live for ever (ours is four years old and is like a family pet!), providing plentiful, cheap and very tasty kombucha.

Can you overdo the kombucha? Yes, particularly if you are not used to fermented foods. If you have irritable bowel syndrome, fermented foods are best avoided. And do bear in mind that many commercial kombuchas come with added sugar and lots of calories, so check the ingredients. Kombucha is also carbonated and too much may lead to bloating.

I think 400ml is pretty safe, but I wouldn’t drink more than that on a daily basis.

I W ANT t o f ollow y our h ighintensity e xercise p lans, especially a s I ’ve r ead t hat exercise c an s tave o ff i llnesses, but I h ave p ain a nd l imited j oint mobility a nd c an’t m anage anything m ore t han w alking. What d o y ou r ecommend?

WALKING is an excellent way of keeping mentally and physically fit. See if you can manage three ten-minute walks a day, ideally as briskly as possible. I would also recommend downloading the free NHS app Active 10, which I’ve found really helpful.