What Really Happens When You Quit Sugar?

Introduction

Have you ever tried to cut back on sugar and felt surprisingly awful?

Maybe your energy crashed. You became irritable. You thought about dessert constantly. By day three, the cookies in the pantry seemed to be communicating with you.

People often interpret this experience as a lack of discipline. They assume they simply need more willpower.

But researchers have been asking a more interesting question: When some people stop eating sugar, do they experience symptoms that resemble withdrawal from an addictive substance?

The idea that sugar may be addictive has been debated for years. Much of the previous research, however, relied on asking people to remember what happened after they tried to quit. Human memory is not exactly a security camera. We forget details, exaggerate others, and reconstruct past experiences based on how we feel today.

A 2026 study published in Appetite tried to improve on that approach by following people throughout a two-week sugar-reduction attempt and asking them about their symptoms several times each day.

The results suggest that withdrawal-like symptoms are real for some people. They also show why we should be careful about jumping from “this feels like withdrawal” to “sugar is definitively an addictive drug.”

What the Science Says

Researchers recruited 203 adults from New Zealand who consumed free sugars every day and were willing to try avoiding them for two weeks.

Free sugars generally include sugars added to foods and drinks, along with sugars found in products such as syrups, honey, and fruit juice. Participants were not being asked to eliminate every naturally occurring sugar from foods such as whole fruit or plain dairy products.

The participant group was predominantly female, at 85 percent. The median age was 38, and the median body mass index was 27.

Before attempting to quit, participants completed questionnaires measuring:

Their usual sugar intake

Food cravings

Confidence in their ability to change

Anxiety, stress, and psychological distress

Symptoms associated with food addiction

Researchers assessed food-addiction symptoms using the Yale Food Addiction Scale, a questionnaire designed to identify patterns resembling substance-use disorders, such as strong cravings, loss of control, unsuccessful attempts to cut back, and continued use despite negative consequences.

Participants were then instructed to avoid free sugars for 14 days.

Throughout the study, they completed five short smartphone surveys per day. This produced as many as 70 check-ins per person.

This method is known as ecological momentary assessment. Instead of asking participants to remember how they felt several days ago, researchers collected information while people were going about their normal lives.

The surveys asked whether participants had consumed sugar and whether they were experiencing symptoms such as:

Cravings

Difficulty remaining sugar-free

Reduced satisfaction or tolerance

Withdrawal-like symptoms

Preoccupation with sugar

Time spent thinking about or trying to obtain sugary foods

What happened during the two weeks?

Nearly one-third of participants remained completely free from added and free sugars throughout the full 14 days.

Across all smartphone surveys, participants reported consuming sugar during only 9 percent of check-ins. Sugar consumption was most common in the evening and usually came from snacks and desserts.

The most frequently reported symptoms were:

Low energy or other withdrawal-like symptoms during 28 percent of check-ins

Cravings during 21 percent

Preoccupation with sugar during 20 percent

Body aches or pain during 15 percent

Low mood during 12 percent

Those symptoms are worth taking seriously. However, there was no control group continuing its normal diet for comparison.

That limitation matters.

We cannot tell whether the sugar-reduction group experienced more low mood, fatigue, aches, or cravings than people normally experience during an ordinary two-week period. Work stress, poor sleep, illness, menstrual symptoms, training fatigue, reduced calorie intake, caffeine changes, and everyday life could have contributed.

The study shows that people reported these symptoms while reducing sugar. It cannot prove that sugar withdrawal directly caused every symptom.

Two very different experiences emerged

After collecting the data, researchers identified two groups based on the number and intensity of symptoms they reported.

Forty-seven percent of participants fell into a lower-symptom group. The other 53 percent fell into a higher-symptom group.

The differences were substantial.

Within the lower-symptom group, 49 percent remained completely sugar-free for the full two weeks. These participants experienced an average of 20 craving episodes during the study.

Within the higher-symptom group, only 14 percent remained sugar-free. They experienced an average of 42 craving episodes—more than twice as many.

This suggests that asking whether sugar reduction is “easy” or “hard” for the average person may be the wrong question. People appear to have very different experiences.

Who was more likely to struggle?

Several characteristics measured before the study predicted whether someone would end up in the higher-symptom group.

Compared with participants reporting fewer symptoms, those in the higher-symptom group were more likely to have:

Met food-addiction criteria on the Yale Food Addiction Scale

Higher anxiety

Higher stress

Lower confidence in their ability to quit

Stronger cravings before beginning

A higher BMI

Participants who met food-addiction criteria had approximately three times the odds of falling into the higher-symptom group.

Each 10-point increase in anxiety was associated with 92 percent higher odds of experiencing high symptoms. A 10-point increase in stress was associated with 84 percent higher odds.

A 10-point decrease in self-efficacy—the belief that you can successfully perform a behavior—was associated with 75 percent higher odds of high symptoms.

Stronger cravings before quitting were also predictive. Each 10-point increase in pre-existing cravings was associated with 58 percent higher odds of landing in the higher-symptom group.

BMI was associated with a smaller increase in risk: approximately 6 percent higher odds for every additional BMI point.

These findings do not mean that anxiety, stress, body weight, or low confidence automatically cause sugar addiction. They suggest that the experience of cutting back is influenced by far more than the sugar content of the food itself.

Psychological distress, learned habits, coping strategies, environment, expectations, and previous experiences may all shape what happens when someone tries to quit.

Does This Prove That Sugar Is Addictive?

No.

The study found that some people experienced symptoms resembling those used to diagnose substance-use disorders. That is meaningful, but resemblance is not the same as proof.

Sugar does not act exactly like nicotine, alcohol, opioids, or other addictive substances. Foods containing sugar also contain varying combinations of fat, starch, salt, texture, flavor, and calories. These foods are often eaten in emotionally meaningful situations and are heavily marketed, convenient, inexpensive, and easy to access.

A craving for ice cream may involve sweetness, fat, temperature, texture, habit, reward, hunger, stress relief, and the fact that it is sitting six feet away in the freezer.

That is more complicated than one ingredient hijacking the brain.

The study also did not randomly assign participants to sugar abstinence or a control diet. Sugar intake was self-reported, and researchers could not independently verify that participants avoided all free sugars.

The sample was predominantly female, and everyone volunteered to attempt sugar abstinence. These participants may have been more concerned about sugar or more motivated to change than the general population.

The trial lasted only two weeks, so it cannot tell us what happens over several months or whether the reported symptoms would continue, disappear, or change.

A reasonable conclusion is that some people experience substantial cravings and withdrawal-like symptoms when they sharply reduce sugar. The study does not establish that sugar should be classified as an addictive substance in the same way as nicotine or alcohol.

What This Means in Real Life

The most useful takeaway is not that everyone needs to quit sugar.

It is that people differ.

Some can decide to stop drinking soda or eating dessert every night and feel relatively fine. Others experience intense cravings, low energy, irritability, repeated lapses, and constant thoughts about food.

Telling the second group to “just be more disciplined” is not especially helpful. They may be dealing with a combination of strong food cues, stress, anxiety, established routines, low confidence, and foods that have become an important source of comfort or relief.

That does not remove personal responsibility. It gives us better information about what the person is actually responsible for changing.

A cold-turkey approach may not be necessary

The participants in this study attempted to remove all free sugars at once. That created a useful research experiment, but it is not automatically the best real-world strategy.

For many people, gradual reduction will be easier to sustain.

Someone might begin by changing the behavior that contributes the most sugar with the least enjoyment. That could mean replacing a daily soda, reducing the amount of sweetener in coffee, buying a less-sweet breakfast cereal, or eating dessert four nights per week instead of seven.

The goal does not have to be a life entirely free from sugar.

It may simply be reaching a point where sugary foods are enjoyable but no longer feel compulsory.

Stress may need attention before sugar does

Higher anxiety and stress were among the strongest predictors of difficulty.

That makes sense. Sweet foods can provide comfort, pleasure, stimulation, routine, or a brief break from an unpleasant emotional state.

Removing the food without replacing the function it serves leaves a gap.

If someone regularly eats sweets after a brutal workday, the problem may not be solved entirely by purchasing sugar-free cookies. The end-of-day stress still needs somewhere to go.

Sleep, workload, meal timing, hunger, social support, emotional coping, and the home food environment may all influence whether reducing sugar feels manageable.

Expectations can help

The study suggests that the first several days of a large reduction may be uncomfortable for some people.

Knowing that cravings, fatigue, or irritability may occur can prevent someone from interpreting those feelings as proof that they are failing.

At the same time, we should not automatically label every headache or bad mood as “detox.” That term is frequently used to give ordinary symptoms a dramatic biological explanation.

Someone may feel poorly because they are eating fewer calories, skipping meals, drinking less caffeine, sleeping badly, changing several habits at once, or expecting the process to be miserable.

Context matters.

Confidence is built through experience

Lower self-efficacy predicted greater difficulty during the study.

Confidence is not merely positive thinking. People become more confident after collecting evidence that they can perform the behavior.

A person who has repeatedly attempted a strict sugar ban and quit after three days probably does not need a more enthusiastic speech. They need a smaller challenge they can complete.

That might mean:

Replacing one sugary drink each day

Eating a filling meal before the usual evening craving

Keeping sweets out of immediate sight

Buying individually portioned desserts

Pairing dessert with a normal meal rather than waiting until extremely hungry

Planning the foods they genuinely want instead of grazing on whatever is available

Small successes do not look dramatic on social media, but they build the skills and confidence required for sustained changes.

Closing Thoughts From Two Decades of Coaching

I have seen people who can keep chocolate in the house for six months and people who hear a package open from three rooms away.

Their experiences are not identical, so their strategies should not be identical either.

Sugar can be pleasurable, easy to overconsume, and deeply woven into our routines. It can also be part of a healthy diet. A person does not need to fear birthday cake, fruit, flavored yogurt, or every gram of added sugar to improve their health.

For many people, the most useful goal is not abstinence. It is flexibility and control.

Can you enjoy something sweet without feeling compelled to continue eating it?

Can you keep your overall diet nutritious without making certain foods morally forbidden?

Can you reduce an unhelpful habit without turning the process into a punishment?

And when you struggle, can you examine the circumstances instead of declaring that you have no willpower?

This research gives us a better reason to take those struggles seriously. Some people genuinely experience more intense symptoms when reducing sugar, particularly when they already have strong cravings, high stress, anxiety, or little confidence in their ability to change.

That does not mean they are broken or permanently addicted.

It means the plan may need to account for the whole person—not merely the nutrition label.

Good nutrition should improve your health while leaving enough flexibility to live your life. The best approach is usually the one that helps you eat well consistently without making food the center of every thought.

References

Bijker R, Henry NIN, Rodda SN. Ecological momentary assessment of symptom trajectories during sugar reduction: Application of substance use disorder criteria. Appetite. 2026;223:108549.

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