Sugar has inspired love songs for generations, but what is it about this little molecule that makes our brains and hearts feel so good? Turns out a lot of the explanations are weirdly similar to how we love people too.  

1. “Don’t judge a book by its cover”

Not all sugars are equal. Many of us use the term “sugar” broadly, to encompass anything that tastes sweet. But the term sugar can refer to lots of different kinds of molecules. Four common types include lactose (in milk), glucose (in starches), sucrose (refined sugar), and fructose (in fruits).

2. “It was love at first sight”

Just looking at our food sets up expectations about how it will taste, including how sweet it will be. It’s no surprise that nearly 80% of people in a 2016 study associated the color pink with the taste “sweet.” That’s more than any other color tested, with purple coming in second at around 45%.

3. “The way to a man’s heart is through his stomach”

Scientifically speaking, the way to a man’s heart is through his small intestine. But that doesn’t sound nearly as romantic.

Your stomach is great at breaking food down into super tiny molecular pieces. But most of the food that’s in your stomach stays there until it moves on to the small intestine. Only then can those food molecules – including simple sugars – actually be absorbed into the bloodstream and circulate back to the heart.

4. “It’s a chemical attraction”

Sugar loves water. It’s “hygroscopic,” meaning it’s very attracted to water. That’s because sugar molecules have a lot of chemical features that like sticking to water. If you’re a baker, you probably already know this. It’s the reason why adjusting the amount of sugar in your baked goods also affects how moist they are.

5. “You complete me”

When sugars are broken down, they generate building blocks for practically every type of molecule in our cells. Metabolized sugars are used to build fats and proteins. We even have sugar (ribose) in our DNA!

6. “Timing is everything”

Timing is everything when it comes to digestion. It’s why eating whole fruits may be better than drinking a glass of juice. Fruits have fiber, which slows down how quickly sugar gets dumped into our bloodstream. Slower more gradual changes in blood sugar are easier for our bodies to deal with.

7. “Love is blind”

Love is blind and so are taste buds. Anything that gets broken down into simple sugars and absorbed into our bodies can be perceived as sugar. It doesn't need to taste sweet.

Starchy foods like bread and bagels don’t taste that sugary compared to a cookie or a scoop of ice cream, but starches are still eventually broken down into simple sugars. As these sugars get absorbed into our blood, that can signal to our brain that we’ve eaten something sweet (even if it didn’t taste that way).

8. “You’re beautiful inside and out”

There are taste receptors on the outside of your tongue and inside your gastrointestinal tract, keeping those tasty treats attractive to our bodies from start to finish.

This is also one of the reasons why our brains can detect sugars even if something doesn’t taste sweet, because “tasting” happens throughout our digestive system.

9. “Can’t get you off my mind”

While many scientists still hesitate to call sugar “addictive,” there is a biological reason why quitting sugar can feel so hard. Eating sugar causes a surge of dopamine, the same chemical released during sex and while taking addictive drugs.

There’s even evidence playing video games, listening to music, and drinking booze can release this chemical as well. All that dopamine is part of what makes eating sugar feel so good.

10. “Everything happens for a reason”

The human body only creates a handful of enzymes that break down sugars. We can break down starches, sucrose, lactose (some of us), and that’s basically it. Which sugars you can digest depends entirely on which enzymes your body produces. Everything else goes straight to your gut.

11. “Trust your gut”

The complex sugars we don’t break down, like fiber, become food for the microbiome in our gut. How we feed these microscopic critters can have a significant effect on our overall well-being. Eating a variety of plant-based foods helps give your microbiome a hearty meal of complex carbs.

12. “Love conquers all”

At the end of the day, we couldn’t metabolize sugar at all without a molecule called NAD (nicotinamide adenine dinucleotide). In one sense, NAD conquers all. It’s a necessary part of how our cells break down sugar to generate energy.