Why is it so hard to give up sugar? It’s a daunting challenge for some people but less so for others. The reason? Some people get more pleasure out of nibbling on something sugary than others. Recent research shows we don’t all get equal gratification from munching on something sweet. You’ve probably known people who preferred salty foods, like pretzels and nuts, to something sweet, and others who couldn’t resist a bowl of ice cream or a warm chocolate brownie. According to a new study shows, these preferences have a lot to do with genetics.
What’s Sweet to You May Be Less Sweet to Someone Else
Researchers at the Monell Chemical Senses Center used twins, both identical and fraternal, to see if there were differences in how they responded to sugar. In total, they analyzed the taste responses of 695 groups of twins as well as siblings, who were not twins. After asking the participants to taste two forms of sugar, fructose, and glucose, they also tested their response to artificial sweeteners. What they concluded is that there are individual differences in perceived sweetness. Some people experience sweet tastes more strongly than others based partially on genetics. The researchers estimate that 30% of the difference in how sweet tastes are perceived is genetic in origin.
What does this mean? Some folks have an unfair advantage when it comes to avoiding sugar. If you’re a person who’s a weak responder, sweet things may not excite your taste buds as much as a die-hard sweets lover. As a result, you may have an easier time saying no to cookies, brownies, pastries, and soft drinks while your friends struggle to resist them. On the other hand, it could work the opposite way. If you’re a weak sugar taster, you may eat more of a sugary food because it takes more of it to get the same degree of gratification.
This research is consistent with other research showing differences in taste perception based on genetics. Studies show some people are more sensitive to bitter flavors than others, which explains why certain individuals dislike bitter vegetables like leafy greens. The degree to which veggies taste bitter to you depends on your ability to taste a compound called phenylthiocarbamide (PTC).
How well an individual tastes PTC is correlated with taste preferences for bitter foods like grapefruit juice and some vegetables. If you taste PTC, you’ll likely find these foods taste unpleasantly bitter while a non-PTC taster wouldn’t pick up on the bitter undertones. This explains why we don’t all have the same food preferences and why you might like a certain food while your best friend despises it.
Although PTC itself isn’t in bitter foods like vegetables, chemicals that are similar in structure are. These chemicals activate taste receptors the same way PTC does and leave a bitter aftertaste. Broccoli, Brussels sprouts, and cabbage are examples of vegetables with potentially bitter-tasting chemicals.
Overcoming Inclinations to Eat Unhealthy
As you can see, based on differences in genetics, some people have an easier time eating a healthy diet than others. Depending on how your taste buds respond to sugar and bitter foods, you may have a strong preference for sweet things and an aversion to vegetables – not a favorable combination if you’re trying to clean up your diet.
Interestingly, many of the healthy compounds in plant-based foods are acidic and bitter. As a result, food manufacturers often remove them to create a more taste-pleasing product through processing and by selectively breeding the plants to have fewer of these chemicals. These compounds are bitter for a reason – they evolved to protect plants from being eaten, including being devoured by humans. Sadly, the foods that naturally taste the most bitter, like vegetables, may be better for you, and the sweet stuff that tastes so good, not so much.
Are Sweet Sugar Foods Addictive?
To make matters worse, there’s evidence that sugar is addictive. In some people, sugar seems to light up reward centers in the brain, stimulating the release of a brain chemical called dopamine. Stimulating those reward centers feels good, so you eat more sweet stuff, but after a while, the portions of your brain that make you feel rewarded become desensitized and you have to devour more sugar to get the same feel-good sensations. See how it can be addictive?
So, if your taste buds light up in response to sugar and are repelled by bitter vegetables, how can you eat a low-sugar, whole food diet and not be miserable? Retrain your brain and taste buds. First, reduce your access to sugary foods. Clean out your cabinets and remove cookies, candy, and other foods with added sugar. When you have a craving for something sweet, snack on something with natural sugar like an apple. Introduce more protein into your diet to stabilize your blood sugar and reduce cravings. Once you’ve successfully avoided sugar for a few weeks, your cravings for sugar should weaken. If you can’t successfully let go of sugar “cold turkey,” take small steps by gradually reducing the amount of sugar in your diet – one less teaspoon of sugar in your coffee each week etc.
How about veggies? Choose vegetables that aren’t bitter like squash, carrots, sweet potatoes, and cauliflower. Broccoli, Brussels sprouts, and green, leafy vegetables are some of the worst offenders. You can get around the bitterness by roasting these vegetables to caramelize them. Another tip is to buy baby vegetables, which tend to taste less bitter. Preparation matters too. After steaming vegetables for a minute or so, drop them into a vat of cold water. This helps prevent the bitter flavors from developing. You can also mask the bitterness by eating veggies with a tasty sauce.
The Bottom Line
If you love sugary foods and dislike vegetables more than your spouse or close friends, they may taste different to you. That doesn’t mean you can’t enjoy vegetables and cut back on sugar. It all comes down to motivation and preparation. Nothing tastes better than being fit and healthy.
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NPR. “The Gene for Sweet: Why We Don’t All Taste Sugar the Same Way”
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