Garlic, alcohol, meat and even fasting can affect our body odour – and alter how appealing our scent is to others.

Each one of us has a unique scent profile, like a fingerprint. Everything from our personality type – such as extroversion, dominance and neuroticism – to our mood and health affects the way we smell.

"The past few decades have revealed that odour is shaped by our genes, hormones, health, and hygiene," says Craig Roberts, professor of social psychology at University of Stirling in Scotland. "Whether we are male or female, young or old, gay or straight, dominant or subordinate, ovulating or pregnant, sick or well, happy or sad."

Many of these factors are out of our control – but not all. A significant influence on the way we smell is the food we eat. Not only does this affect our overall aroma, but also how we are perceived, including how attractive we appear to others, according to a small but growing body of research.

On a biological level, food affects our body odour by two main routes, says Lina Begdache, an assistant professor of health and wellness studies at the State University of New York at Binghamton. Those are our guts and our skin.

First, the gut. As you digest your food, bacteria are at work metabolising it inside your gut. Some of those interactions between food chemicals and bacteria release gases – volatile molecules that make it out of your body the same way the food went in, says Begdache. This can result in bad breath, or halitosis, especially depending on what you eat (more about this later). Data suggests that about one-third of adults worldwide suffer from some form of halitosis, though there are other causes besides digestion.

Second, the skin. Chemical components from your food, once metabolised, also travel through the bloodstream and many of the body's tissues. Some end up being perspired through the skin, where they interact with the skin's bacteria and create a smell there, too. (Yes, sweat in itself is odourless; it's the skin bacteria that thrive in sweat that makes sweat smelly.)

Different foods have a variety of chemical compounds that come into play at different stages, resulting in varying levels of stink. But the foods with the most pungent results almost always have one culprit in common: sulphur. Surprisingly, though, some studies do suggest these odorous compounds can have an unexpected effect of making us more attractive.

Broccoli, cabbage, Brussels sprouts and cauliflower may be staples of a healthy diet – but they are heavily packed with sulphurous compounds, which can often be reminiscent of the smell of rotting eggs. When these compounds make their way through the bloodstream and interact with skin bacteria, your sweat can turn into a strongly pungent liquid, according to nutritional therapist Kerry Beeson.

Foods from the allium family, such as garlic and onions, can also affect the smell of our sweat and breath for the same reason as cruciferous vegetables: when they're metabolised by the human body, they break down into stinky compounds like diallyl disulphide and allyl methyl sulphide, which are emitted by your body in slightly different timelines – right after ingestion and then, in the case of allyl methyl sulphide, with a peak 30 minutes later.

Surprisingly, though,

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