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  • A new study has found a link between drinking unsweetened coffee and weight loss.
  • Increases in caffeine consumption were also linked to changes in weight.
  • However, the addition of a teaspoon of sugar canceled out the benefit.
  • Experts say coffee may aid weight loss by triggering calorie burning or suppressing appetite.
  • Unsweetened coffee can help people lose weight because they are taking in significantly fewer calories.

Statistics reveal that Americans love their coffee. In fact, 74% of people surveyed by Drive Research reported enjoying the steamy beverage on a daily basis.

Scientists say that coffee consumption can be a healthy habit.

Drinking moderate amounts of coffee has been linked to lower rates of a range of health conditions, including type 2 diabetes and cardiovascular disease.

Now, we may be able to add another benefit to the list. A study published October 1 in The American Journal of Clinical Nutrition reports that drinking coffee is associated with weight loss. However, there is one catch — it must be drunk unsweetened.

The study authors noted that coffee is often consumed along with sugar, artificial sweeteners, cream, or non-dairy creamers.

The researchers wanted to investigate the relationships between how much coffee people drank, how much caffeine they consumed, and how their weight changed when considering what they added to their coffee.

They also wanted to examine whether coffee or caffeine could mitigate any weight change due to adding sugar.

The large study included 48,891 people from the Nurses’ Health Study, 83,464 people from the Nurses’ Health Study II, and 22,863 people from the Health Professional Follow-up Study.

All participants were asked to fill out questionnaires regarding their food and beverage consumption during the past year as well as over the next four years.

Data was collected for how much coffee they drank — both caffeinated and decaf — as well as what they chose to add to it.

The researchers then analyzed the data to determine what relationships existed between coffee intake and people’s weight throughout the course of the study.

They found that an increase in coffee consumption of one cup of unsweetened coffee was linked to a decrease in weight of around 0.12 kilograms (0.26 pounds).

On the other hand, when people increased their daily sugar intake by one teaspoon in any food or drink, they gained 0.09 kilograms (0.20 pounds).

Cream and non-dairy creamer did not appear to have any effect on weight.

The research team additionally noted that changes in coffee or sugar intake had a stronger effect on weight in both overweight and obese individuals and in younger people.

They further found that caffeine also affected weight. When people’s intake rose by 100 milligrams, the amount of caffeine found in a cup of coffee, weight gain was reduced by 0.08 kilograms (0.18 pounds).

Based on on their findings, the scientists concluded that, while increased coffee intake helped people lose weight, adding a teaspoon of sugar canceled out the effect.

Dr. Colleen Gulick, an exercise physiologist, explained that there were several ways in which coffee might affect weight.

One is its thermogenic effect. “Caffeine, a key component of coffee, is known to stimulate thermogenesis, which is the process by which the body generates heat and burns calories,” she explained. “This thermogenic effect can increase energy expenditure.”

A second way coffee might impact weight is through suppressing appetite. “Caffeine has been shown to have appetite-suppressing properties, which may reduce overall caloric intake,” she said.

A third property of coffee to look at, according to Gulick, is its metabolic effects. “Coffee contains bioactive compounds, such as chlorogenic acids and polyphenols, that have been linked to metabolic benefits, including improved insulin sensitivity and glucose metabolism,” she said. “These effects could potentially influence body weight regulation and contribute to weight loss.”

A fourth way coffee may influence weight loss, said Gulick, is through enhancing physical performance. “Caffeine has been shown to improve endurance and physical performance,” she observed. “By increasing exercise capacity and intensity, regular consumption of unsweetened coffee might indirectly support weight loss efforts through increased calorie expenditure during physical activity.”

And, finally, there are reasons outside of coffee itself that unsweetened coffee might aid weight loss, according to Michelle Saari MSc, RD. It could come down to the difference in calories that you are consuming.

“People tend to fill their coffee cups with sugar, sweeteners, and rich creams,” she said. “If you’re adding all of these to your daily cup of coffee and having multiple cups per day you could be adding hundreds of extra calories simply in a cup of coffee.”

Giving an example, Saari noted that a medium black coffee at Starbucks with a shot of sugar-free syrup comes in a only 5 calories.

By contrast, drinking a caramel macchiato will give you 250 calories and a hefty 33 grams of sugar.

“So if you’re having trouble losing weight, consider switching to sugar-free syrup and avoiding the sugar-heavy drinks,” she advised.

Dr. Alex Foxman, medical director of Achieve Health and Weight Loss, said that, while coffee has many health benefits, it may also have adverse effects on some people.

“For example, coffee can cause insomnia, anxiety, jitteriness, palpitations, and gastrointestinal distress in some individuals,” he said,” especially those who are sensitive to caffeine or consume large amounts of it.”

Foxman further noted that coffee can interact with medications and supplements, including anticoagulants, antidepressants, iron, and calcium.

“Therefore, people who increase their coffee intake should consult their doctors if they have any medical conditions or take any medications that may be affected by coffee,” he advised. “They should also monitor their caffeine intake and avoid drinking coffee too close to bedtime or on an empty stomach.”

While increased coffee consumption was linked to weight loss, researchers found that adding sugar was linked with weight gain, mostly canceling out the benefits.

Experts say that if you are seeking to lose weight, unsweetened coffee is the way to go.

If you are looking to increase your coffee intake, however, be aware that added caffeine intake may come with certain side effects, like jitteriness or sleeplessness. It can also interact with certain medications and minerals. You should consult with your physician if you have specific health concerns that might be negatively affected by caffeine.