Are you able to well being hack your immune system?

It’s a chilly morning within the depths of winter.

And I really feel like I’ve left my sanity in addition to my heat garments within the altering room as I stride out to the sting of a reservoir in my swim shorts.

A brightly-coloured chalk signal informs me that the water temperature at the moment is a cold 3.9C, as one of many regulars tells me this isn’t chilly water swimming, it is “ice” water swimming.

How did I find yourself right here?

Nicely, I’ve change into enthralled by the concept of enhancing or boosting the immune system. My physique has been the residing embodiment of the “quademic” that the NHS spent all winter warning us about. It has been a relentless stream of colds and coughs and one explosive tummy.

Our immune programs already do a incredible job combating viruses and different nasties. If I collected all of the air I breathed out over the course of a minute it will include 100 to 10,000 micro organism, 25,000 viruses and a single fungi, in response to Prof John Tregoning, immunologist at Imperial Faculty London.

“You are respiration these items in on a regular basis, there’s only a swirling mass of pathogens [organisms that cause disease] within the air,” he says.

However there’s loads of meals, dietary supplements and actions which can be touted for his or her “immune-boosting” properties. Can we dial up our safety?

And that is why I discover myself wading out and pushing off for a chilling blast of breaststroke.

The icy water is like fireplace on my pores and skin and all my mind can consider is making it to the pontoon while not having assist from the lifeguards.

However research have proven the adrenaline hit of the chilly water does flood the blood stream with infection-fighting cells.

White blood cells – which might produce antibodies or assault contaminated tissue – transfer out of their regular properties and head out on patrol considering there may very well be an an infection. So does this imply I am extra protected?

“Inside a number of hours that each one goes again to regular,” says Prof Eleanor Riley, an immunologist on the College of Edinburgh.

“There isn’t a proof that individuals who go chilly water swimming have fewer colds or fewer infections.”

There won’t be the proof for chilly water, however common train might effectively do the trick.

On common adults get two to 3 colds per yr and kids between 5 and eight, says Dr Margaret McCartney, a GP and knowledgeable in evidence-based drugs, on the College of St Andrews.

“[But] individuals who do reasonable quantities of train are inclined to report fewer viral infections,” she says.

There’s a lack of conclusive scientific trials, however the information we have now is “all pointing within the path of it being good for you… however not a miracle remedy,” in response to Dr McCartney.

Laboratory research have instructed common train might gradual the ageing of the immune system. Your physique’s defences are in decline from our 20s onwards, however analysis on 80-year-old cyclists instructed that they had the immune programs of individuals many years youthful.

“I do know the trials have probably not been completed in excessive sufficient high quality, however I will be doing a number of biking,” she says.

The very first thing that springs to my thoughts is vitamin C – both by devouring a mountain of oranges or in tablet type.

“It is a no from me,” says Dr McCartney. Being poor might impair the immune system, however for the overwhelming majority there’s little to be gained from having further. The identical goes for multivitamins, which says Dr McCartney simply make “costly urine”.

Nevertheless, the proof round vitamin D is hotly debated relatively than being a agency no. Vitamin D ranges dip in winter as it’s made when our pores and skin is uncovered to daylight.

“I believe the proof is pointing in the direction of potential advantages for individuals who’ve acquired respiratory illness and who’re very low in vitamin D,” says Dr McCartney, however there’s “inadequate” proof that it will assist everybody.

And when you’re considering what you may put within the purchasing trolley, the jury continues to be out on whether or not prebiotics and probiotics that change the great micro organism in your intestine additionally profit immunity.

“I do imagine that may be a actually necessary space of research, however we’re missing the actual world information that will allow you to advocate this,” says Dr McCartney.

She additionally says echinacea, turmeric and ginger pictures should not going to present you an immune enhance.

Your immune system’s talents should not fastened all through the day.

“Our immune system is handiest within the early morning at across the time we get up, continues to be extremely efficient via the early a part of the day after which in a while within the day it begins to wind down,” says Prof Riley.

For this reason your chilly typically feels worse within the morning as your signs are the results of an immune system firing on all cylinders.

The decline kicks in “about 4 or 5 o’clock within the afternoon”, so that you might need higher safety if you’re vaccinated, or uncovered to somebody coughing, within the morning.

Because the immune system does have this 24-hour cycle, then having “a daily day by day rhythm” relatively than a mixture of late nights and lengthy lie-ins on the weekend “might effectively assist enhance your immune system”, says Prof Riley.

Whereas we’re considering of boosting our immune system we also needs to keep in mind there are issues that really improve our vulnerability to an infection.

One of many huge ones is smoking as a result of it immediately damages the lungs so they’re a much less efficient barrier to viruses.

“For those who think about the lungs like a sieve, smoking will break holes within the sieve, so extra can get via,” says Prof Tregoning.

It additionally dials up irritation all through the physique. Irritation is sort of a thermostat for the immune system and is a standard a part of how the physique reacts to an an infection.

However “uncontrolled irritation is dangerous for you” because it disrupts the immune system “so chances are you’ll reply much less effectively”.

Weight problems is one other issue that may improve susceptibility to infections in addition to the severity by ramping up irritation within the physique.

“Each of these issues might be tough for individuals to cease or to reverse, however they’re in all probability probably the most modifiable ones,” says Dr McCartney.

Being continuously burdened raises ranges of the hormone cortisol within the physique.

But, cortisol dampens the immune system which can go away you extra susceptible to an infection.

Prof Tregoning says this can be the reason for why being in nature, going for a stroll, spending time with pals – even chilly water swimming – might have some useful impact.

“You are much less burdened, much less cortisol, so subsequently your immune system is healthier for the position it’s attempting to do,” he says.

Prof Riley provides: “There may be completely little question that being pleased, being in a constructive way of thinking, has a really, essential impact on our bodily features.”

You may have in all probability seen merchandise within the store you could spray up every of your nostrils on the first signal of a chilly.

A report within the Lancet confirmed they do work.

It gave hundreds of individuals both a salt water (saline) spray or a gel-based one. They might use it as much as six instances a day every time they felt they have been coming down with one thing.

Individuals who simply went about their day by day lives with no nasal spray spent a median of eight days being ailing throughout the research.

However that fell to 6 days in these utilizing a both salt water (saline) or a branded gel-based spray.

Dr McCartney argues {that a} branded spray can be no higher than a standard saline spray.

If you’re already doing all the same old issues to take care of your well being – not smoking, consuming healthily, exercising usually – then your immune system is already within the “absolute best situation” to answer an an infection, says Prof Riley.

“Are you able to do something to spice up above being a standard, wholesome individual? There’s simply no actual proof you could,” she says.

“However there are issues you are able to do to enhance your immunity in opposition to specific particular person infections and that’s to be vaccinated.”

And perhaps as an alternative of spending your cash on the newest immune-boosting craze, she suggests eager about methods of not getting contaminated within the first place so “watch out who you socialise with”.

Inside Well being was produced by Hannah Robins and the programme airs on BBC Radio 4 on Tuesdays at 09:30 GMT and on BBC Sounds.