To eat or not to eat?

You make big decisions every day. Will your lunch today be the leftover wholefood stew you brought from home or will you go to the café around the corner where you are pretty sure the new person serving gives you an unusually intimate smile? Do you send that email pointing out to your brother that a $50 fuel voucher is an inappropriate gift for a five-year-old? On the drive home will you listen to a soul edifying podcast on the nature of serenity or the daily gristle-chewing from a shock-jock full of self-importance? Yes, decisions abound and none more pressing than that moment when a long-cherished and anticipated food item falls to the floor as your eager fingers fumble it… Do you pick it up and eat it or do you consign it to the trash-bin of history along with your gustatory dreams? Some researchers have just revealed some advice on this most difficult of life decisions.

There is a factoid around that providing you can pick up a piece of dropped food within five seconds then it won’t have gathered enough bacteria to be harmful. Is this an accurate biological observation or just wishful thinking? These researchers set out to see whether the five-second rule holds any water.

The very simple method used to assess this involved measuring the amount of common bacteria E. coli and Staph. Aureus that would transfer to pieces of various foods dropped onto different floor surfaces. The foods used included toast, pasta, biscuits and sticky sweets. The types of floors tested were carpet, laminate and tiles. For each combination of floor and food, the researchers measured the amount of bacteria transferred to the food when it was in contact with the surface for between three and 30 seconds.

The results showed that time is a significant factor in bacterial transfer and that the longer a food is on the floor the more bacteria it picks up. They also found that the floor surface matters in that bacteria is least likely to transfer from carpet and most likely to transfer from laminate and tile.

If a piece of food is only momentarily on the floor, it will have significantly less bacteria on it than if you leave it there for a few minutes. Interestingly, the researchers also found that 87 per cent of people interviewed by the researchers said they had eaten food dropped on the floor and, of these, 55 per cent were women. Additionally, 81 per cent of all people surveyed said they would adopt the five-second rule.

So the five-second rule does have some validity and the bottom line is this: that piece of toast you dropped on the floor this morning, which you will find there when you get home, is probably not the best thing to be eating, no matter how starving you are when you walk through the door.