What’s the difference between sugar, other natural sweeteners and artificial sweeteners? A food chemist explains sweet science

 

Sugar is just one of many flavor enhancers people and companies use to sweeten foods and beverages. Marie LaFauci/Moment via Getty Images

A quick walk down the drink aisle of any corner store reveals the incredible ingenuity of food scientists in search of sweet flavors. In some drinks you’ll find sugar. A diet soda might have an artificial or natural low-calorie sweetener. And found in nearly everything else is high fructose corn syrup, the king of U.S. sweetness.

I am a chemist who studies compounds found in nature, and I am also a lover of food. With confusing food labels claiming foods and beverages to be diet, zero-sugar or with “no artificial sweeteners,” it can be confusing to know exactly what you are consuming.

So what are these sweet molecules? How can cane sugar and artificial sweeteners produce such similar flavors? First, it is helpful to understand how taste buds work.

You perceive sweet flavors when certain molecules bind to the taste buds on your tongue. Bomin Jeong/EyeEm via Getty Images

Taste buds and chemistry

The “taste map” – the idea that you taste different flavors on different parts of your tongue – is far from the truth. People are able to taste all flavors anywhere there are taste buds. So what’s a taste bud?

Taste buds are areas on your tongue that contain dozens of taste receptor cells. These cells can detect the five flavors – sweet, sour, salty, bitter and umami. When you eat, food molecules are dissolved in saliva and then washed across the taste buds, where they bind to the different taste receptor cells. Only molecules with certain shapes can bind to certain receptors, and this produces the perception of different flavors.

Molecules that taste sweet bind to specific proteins on the taste receptor cells called G-proteins. When a molecule binds these G-proteins, it triggers a series of signals that are sent to the brain where it is interpreted as sweet.

Glucose is the simplest of sugars and is a circle of carbon atoms with oxygen and hydrogen atoms attached to the ring. NEUROtiker/WikimediaCommons

Natural sugars

Natural sugars are types of carbohydrates known as saccharides that are made of carbon, oxygen and hydrogen. You can imagine sugars as rings of carbon atoms with pairs of oxygen and hydrogen attached to the outside of the rings. The oxygen and hydrogen groups are what make sugar sticky to the touch. They behave like Velcro, sticking to the oxygen and hydrogen pairs on other sugar molecules.

The simplest sugars are single-molecule sugars called monosaccharides. You’ve probably heard of some of these. Glucose is the most basic sugar and is mostly made by plants. Fructose is a sugar from fruit. Galactose is a sugar in milk.

Table sugar – or sucrose, which comes from sugar cane – is an example of a dissacharide, a compound made of two monosaccharides. Sucrose is formed when a glucose molecule and a fructose molecule join together. Other common dissacharides are lactose from milk and maltose, which comes grains.

When these sugars are eaten, the body processes each of them slightly differently. But eventually they are broken down into molecules that your body converts into energy. The amount of energy from sugar – and all food – is measured in calories.

High fructose corn syrup is the main sweetener for many processed foods and drinks. Jeff Greenberg/Universal Images Group via Getty Images

High fructose corn syrup

High fructose corn syrup is a staple of U.S. foods, and this hybrid sugar sweetener needs a category all on its own. High fructose corn syrup is made from corn starch – the main carbohydrate found in corn. Corn starch is made of thousands of glucose molecules bonded together. At an industrial scale, the starch is broken into individual glucose molecules using enzymes. This glucose is then treated with a second enzyme to convert some of it into fructose. Generally, high fructose corn syrup is roughly 42%-55% fructose.

This blend is sweet and cheap to produce but has a high calorie content. As with other natural sugars, too much high fructose corn syrup is bad for your health. And since most processed foods and drinks are packed full of the stuff, it is easy to consume too much.

A chemical in the stevia plant also produces sweet flavors. Gabriela F. Ruellan/WikimediaCommons

Natural nonsugar sweeteners

The second category of sweeteners could be defined as natural nonsugar sweeteners. These are food additives such as stevia and monk fruit, as well as natural sugar alcohols. These molecules aren’t sugars, but they can still bind to the sweet receptors and therefore taste sweet.

Stevia is a molecule that comes from the leaves of the Stevia redaudiana plant. It contains “sweet” molecules that are much larger than most sugars and have three glucose molecules attached to them. These molecules are 30 to 150 times sweeter than glucose itself. The sweet molecules from monk fruit are similar to stevia and 250 times sweeter than glucose.

The human body has a really hard time breaking down both stevia and monk fruit. So even though they’re both really sweet, you don’t get any calories from eating them.

Sugar alcohols, like sorbital, for example, are not as sweet as sucrose. They can be found in a variety of foods, including pineapples, mushrooms, carrots and seaweed, and are often added to diet drinks, sugar-free chewing gum and many other foods and drinks. Sugar alcohols are made of chains of carbon atoms instead of circles like normal sugars. While they are composed of the same atoms as the sugars, sugar alcohols are not absorbed well by the body so they are considered low-calorie sweeteners.

Chemists have developed a number of lab-made chemicals that taste sweet and are sold as no-sugar sweeteners. Evan Amos/WikimediaCommons

Artificial sweeteners

The third way to make something sweet is to add artificial sweeteners. These chemicals are produced in labs and factories and are not found in nature. Like all things that taste sweet, they do so because they can bind to certain receptors in taste buds.

So far, the U.S. Food and Drug Administration has approved six artificial sweeteners. The most well known are probably saccharin, aspartame and sucralose – better known as Splenda. Artificial sweeteners all have different chemical formulas. Some resemble natural sugars while others are radically different. They are usually many times sweeter than sugar – saccharin is an incredible 200 to 700 times sweeter than table sugar – and some of them are hard for the body to break down.

While a sweet dessert may be a simple pleasure for many, the chemistry of how your taste buds perceive sweetness is not so simple. Only molecules with the perfect combination of atoms taste sweet, but bodies deal with each of these molecules differently when it comes to calories.

---

This article is part of a series examining sugar’s effects on human health and culture. To see all articles on this series, click here.

Kristine Nolin, Associate Professor of Chemistry, University of Richmond

This article is republished from The Conversation under a Creative Commons license.

Regret can be all-consuming – a neurobehavioral scientist explains how people can overcome it

 

Regret can increase stress and negatively affect one’s physical health. JGI/Tom Grill via Getty Images

A friend of mine – we will call him “Jay” – was working for IBM in New York City in the early ‘90s. He was a computer programmer and made a good salary. Occasionally, competitors and startups approached Jay to join their companies. He had an offer from an interesting but small organization in Seattle, but the salary was paltry and most of the offer package was in company shares. After consulting with friends and his parents, Jay declined the offer and stayed with IBM. He has regretted it ever since. That small company was Microsoft.

Regret is a very real reaction to a disappointing event in your life, a choice you made that can’t be changed, something you said that you can’t take back. It’s one of those feelings you can’t seem to shake, a heavy and intrusive negative emotion that can last for minutes, days, years or even a lifetime. Imaging studies reveal that feelings of regret show increased activity in an area of the brain called the medial orbitofrontal cortex.

Dealing with regret is even more difficult because of the other negative emotions connected to it: remorse, sorrow and helplessness. Regret can increase our stress, negatively affect physical health and throw off the balance of hormone and immune systems. Regret is not only unpleasant. It is unhealthy.

As a licensed clinical psychologist at the University of Virginia School of Medicine, I conduct research on stressful emotions. Through this work, I help patients overcome regret, move on with their lives and grow. And that is the good news: Regret can be overcome through interventions like therapy and evidence-based strategies.

Therapy can help people consumed with regret to face their feelings and develop resilience. FatCamera/E+ via Getty Images

A 'sense of stuckness’

There are basically two ways to experience regret: One is what researchers refer to as the action path and the other is the inaction path. That is, we can regret the things we did – or we can regret the things we did not do.

Research suggests that action-related regrets, although painful, spur people to learn from their mistakes and move on. But regret related to the inaction path – the things undone, the opportunities lost – is harder to fix. This kind of regret is more likely to lead to depression, anxiety, a sense of “stuckness” and a feeling of longing over not knowing what could have been.

As with other negative emotions, it doesn’t work to avoid, deny or try to squash regret. In the long run, these tactics only increase negative feelings and prolong the time you suffer with them. Rather than stay stuck, people can manage these emotions in four steps: First, accept the fact that you are feeling them; determine why you are feeling them; allow yourself to learn from them; and finally, release them and move forward.

You can help release these feelings of regret by practicing self-compassion. This means reminding yourself that you are human, you are doing the best you can, and you can learn from past decisions and grow. Showing this compassion to yourself can help you accept and move past the regret.

Accepting that you have feelings of regret does not mean that you like these feelings. It just means you know they are there. It also helps to identify the specific emotion you’re feeling. Instead of telling yourself, “I feel bad,” say “This is me, feeling regret.” Simple as it sounds, the semantic difference has a big emotional impact.

Accept, acknowledge and forgive yourself

Acknowledging your thoughts and feelings can bring relief from strong negative emotions. In Jay’s case, he could remind himself that he had no crystal ball. Instead, he made the best decision he could, given the information he had at the time, and given the same circumstances, most of his contemporaries would have made the same decision.

This method of noticing and then restructuring your thoughts is sometimes called cognitive reappraisal. Seeing the situation in a different way may help reduce regret and help you make future decisions.

Forgiving yourself for actions taken or not taken is a powerful step toward overcoming regret. This has been formalized into a commonly used cognitive psychological model called REACH, which asks people to recall the hurt (face it), empathize (be kind and compassionate), altruistically offer forgiveness (to oneself), commit publicly (share it) and then hold on to that forgiveness and stay true to the decision. Research shows that six hours of work with a trained professional using this model can have a positive impact.

Author and journalist Kathryn Schulz reflects on the value of learning to embrace and make peace with regret.

More knowledge = less regret

At first, Jay pushed away his feelings of regret. He continued to struggle with thoughts of what he missed. He did not change until he approached and explored his feelings of regret, first with a friend and ultimately with a therapist.

Eventually, he accepted the pain of not knowing what might have happened, but also reminded himself of his rationale at the time, which was actually quite reasonable. He demonstrated compassion towards himself, and spoke to himself kindly, the way he would when talking to a loved one or close friend. Practicing this self-compassion allowed him to build resilience, move on from the negative emotions and ultimately forgive himself.

On making future decisions, Jay recognized the importance of obtaining as much information about opportunities as possible. He challenged himself to learn about the big players in the field. Doing so allowed him to overcome his regret and move forward. New opportunities came along. Jay, currently employed by another giant computer engineering company, is doing quite well for himself, and has been able to move beyond the regret of his past decision.

J. Kim Penberthy, Professor of Psychiatry and Neurobehavioral Sciences, University of Virginia

This article is republished from The Conversation under a Creative Commons license.