A Foods Standards Agency (FSA) spokesperson said double dipping food if you’re the only person eating it is not the biggest crime, but is “not recommended”, especially if you’re putting leftovers in the fridge to save for later. “While double dipping if you are the only person using the jar is fine in theory - as you are the only person being exposed to any bacterial/viral cross contamination between your mouth and the jar contents - it is poor hygienic practice,” they told HuffPost UK. “Your own saliva contains enzymes that could affect the food over time in the fridge.” Professor Donald Schaffner, a specialist in food science at Rutgers University, agreed that double dipping your own food is “probably not” a problem if you’re not sharing with others. “There is a chance that if you have an infection, i.e. an abscessed tooth, the infection from the tooth can spread to the food,” he told HuffPost UK. “If the bacteria can multiply in the food to high levels they can make a toxin that will make you sick. Then you will have vomiting, diarrhoea and an abscessed tooth.” But the real grossness kicks in when you start double dipping food with a communal sauce that’ll be used by others. The FSA spokesperson said: “We do not recommend this. Bacteria in your mouth could cross-contaminate the food and spread a variety of illnesses, such as colds and flu. You should take a portion of dip onto your plate to eat it instead.” Professor Schaffner added that double dipping shared food could “potentially” be harmful to health. “If you are sick with norovirus and you vomit, you might have the virus in your mouth. Double dipping would spread the virus to the food and make someone else sick,” he said. “Even if it’s low risk, it’s gross. I don’t want to eat your mouth bacteria.” Meanwhile Dr Clare Morrison, the GP for online doctor MedExpress, said you should consider the type of food you’re eating before thinking about double dipping. “Double dipping is pretty yukky, but the extent to which it is actually unhealthy varies depending on the food,” she told HuffPost UK. “For example, researchers have discovered that while all sauces contain more bacteria when a chip has been double dipped, salsa got the worst deal - with more than five times the bacteria in comparison to other two sauces. “It’s believed that this is because salsa is watery, so contaminated parts are likely to fall back into the bowl after dipping.” Dr Morrison also joked that you should “have a close look at the person who’s double dipping” before using a communal sauce. If they look ill, avoid that sauce like the plague. Consider yourselves warned.