Depending on the floor type, don't worry about eating something that's been on the floor. Photo / Getty Images
Welcome to Ask Doctor Zac, a weekly column from news.com.au. This week, Dr Zac Turner reveals why germs are actually good for you.
Question: Hi Dr Zac, my wife and I have different ideas when it comes to the safety of germs. She believes the more germs the better. I believe the less germs the better. We constantly fight over if hand sanitiser or soap is the right choice. She even believes in the five-second rule! Can you settle the debate once and for all – do we benefit from interactions with germs? - Matthew, 38, Victoria
Answer: As a doctor I'm consistently in sterile environments and I regularly clean my hands during my work day. However, at home, I have upped my "bacteria intake" for the sake of stimulating my immune system. Sometimes I even stick to simply washing my hands with water (just like we've done in the past pre-Covid years).
For my patients looking to boost their immune system, I always remind them with the lyrics of J-Lo: "Used to have a little, now I have a lot." A regular exposure to dirt and microbes leads to a social immune system that is prepared for any interaction.
I think many people have become quite germ-a-phobic in the past year, and this can be just as harmful. Just like training for an event, our body is constantly having its defences tested from the microbes we inhale, ingest and touch. Like most people, my own pre-Covid lifestyle involved far more travel, more sport, less isolation and certainly less handwashing (even for a doctor). As a result, the diversity of the microbes I am currently exposed to has drastically reduced.
You need to think of your immune system like a muscle. It works out every time it comes into contact with a germ and builds memory to work against them. I believe I have a strong immune system because I have travelled throughout the world coming into contact with a wide range of germs. This exposure causes my immune system to respond appropriately to pathogens.
I'm sorry to break it to you, but unless you start life out in a bubble, you will always be surrounded by germs. Inside your body right now, there are 10 times more germs than human cells. You need to understand that not all germs are bad for you!
I don't believe in the five-second rule. The better rule of thumb is the "wet test". Is what you've dropped on the floor wet or not? It's all about time and place, as well. A sausage sizzle dropped in the parking lot of Bunnings is worse than one dropped on your kitchen floor.
Not all dropped food is safe. Certain factors make food on the floor more dangerous, such as pets, who can bring in bacteria from time spent outside.
Research suggests dropped food that's moist and sticky will likely have more bacteria attached to it. And in terms of the type of surface, believe it or not, carpet is safer than wooden or tiled floors.
So next time you drop food on the floor, dry is fine but wet must be thrown out.
By eating "dirty" food you are ingesting friendly microbes that build our bodies' immune defence. Friendly bacteria can support our health in a surprising number of ways, such as helping to prevent diabetes, skin infections and from developing allergies such as asthma, psoriasis and eczema.
Should I keep using so much hand sanitiser?
Hand sanitiser is for when you are outside in places such as grocery stores, cinemas or any other place with a high flow of people. At home, I recommend you simply stick to soap and water and even then it is okay sometimes to just use water so you can consume healthy bacteria.
Matthew, I recommend you see your local GP with your wife and talk these things through, your health is very important and you should always look for advice from your doctor rather than the internet.
• Dr Zac Turner has a Bachelor of Medicine and Bachelor of Surgery from the University of Sydney. He is a medical practitioner and a co-owner of telehealth service, Concierge Doctors, and is also a qualified and experienced biomedical scientist.