Artificially-sweetened Drinks Help Promote Weight Loss, But Water Is Best

• A new study reports that replacing sugary beverages with artificially sweetened drinks can help promote weight loss.
• The findings also indicate that drinking water instead of sugar-laden liquids can promote weight loss.
• Experts say that overconsumption of foods and beverages with artificial sweeteners can lead to numerous health issues.

Researchers report that replacing sugary drinks with artificially sweetened drinks can help people lose weight.

Scientists from the Harvard T.H. Chan School of Public Health in Massachusetts also found that replacing sugary beverages with water can lead to weight loss.

The researchers stated that their analysis showed that people who replaced sugary drinks with artificially sweetened beverages achieved modest long-term weight loss, particularly among participants with overweight or obesity and had high sugary beverage intake at the onset of the studies.

They added that participants who replaced artificially sweetened drinks with water experienced modest long-term weight loss, while those who replaced sugary beverages with water had the highest weight loss.

The researchers recently published their findings in the American Journal of Clinical Nutrition.

Experts not involved in the study told Healthline that although artificial sweeteners may help with weight loss, they also pose health risks.

They said water is a much healthier choice as a substitute for sugar-laden beverages.

“Avoiding sweeteners entirely by choosing plain water is the better option,” said Mir Ali, MD, a bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA. “This avoids the adverse effects of both sugar and artificial sweeteners and is beneficial for weight loss.”

“Water provides hydration and is void of additives,” added Kristin Kirkpatrick, RD, the president of KAK Consulting and a dietitian at the Cleveland Clinic Department of Wellness & Preventive Medicine in Ohio. “After all, sugar-sweetened and [artificially sweetened] beverages are considered ultra-processed. Therefore, choosing water is a great way to start reducing [processed foods] in the diet.”

Artificial sweeteners may aid weight loss

For their study, the Harvard scientists analyzed data from 143,000 individuals who participated in the Nurses’ Health Study, the Nurses’ Health Study II, and the Health Professionals Follow-up Study.

Participants were ages 26 to 65. They were followed for 24 to 32 years, with biennial questionnaires that updated medical, lifestyle, and anthropometric data.

The researchers reported that the mean weight gain among participants per 4-year interval was 1.3 kilograms (about 2.8 pounds).

They reported that replacing three servings a week of a sugary beverage with an artificially sweetened drink was associated with a weight loss of 1.39 kilograms.

They said there were similar results when replacing sugary beverages with water. They noted that replacing artificially sweetened drinks with water resulted in only “modest reductions in weight.”

Experts say there are several potential reasons for the weight loss by people who switched to artificially sweetened beverages.

“It’s possible this impact is in large part to overall reduction of calories – thereby taking less energy in may lead to weight loss,” Kirkpatrick said. “Additionally, individuals in the study may be making more effort to improve nutrition overall, which may also lead to better habits and weight loss.”

“[The study] confirms what you’d expect: introducing a calorie-free beverage to replace drinks like juice or soda results in weight loss because you’re consuming fewer calories,” said Jonathan Long, PhD, an associate professor of pathology at Stanford University, who wasn’t involved in the study.

Health risks linked to sugar, artificial sweeteners

The recently updated 2025–2020 Dietary Guidelines for Americans state that no amount of added sugars or artificial sweeteners is considered part of a healthy diet.

The guidelines further note that one meal should contain no more than 10 grams of added sugars, or just under 2.5 teaspoons.

Leading sources of sugar in the typical U.S. diet include sugar-sweetened beverages, desserts, and sweet snacks. These foods include sodas, cookies, brownies, cakes, pies, ice cream, frozen dairy desserts, doughnuts, sweet rolls, and pastries.

It’s estimated that Americans consume about 22 teaspoons of added caloric sweeteners a day. These sweeteners range from 180 to 13,000 times sweeter than sugar. They are marketed under brand names such as NutraSweet, Equal, Sweet’N Low, and Newtame.

The sweeteners are contained in many foods and beverages advertised as “sugar-free” or “diet.” These include baked goods, soft drinks, powdered drink mixes, candy, puddings, canned foods, jams and jellies, and dairy products.

The adverse health effects from a diet high in sugar have been widely reported.

According to the Centers for Disease Control and Prevention (CDC), high sugar consumption can raise the risk of obesity, heart disease, and type 2 diabetes.

High sugar consumption may increase the risk of cancer, depression, cellular aging, and kidney disease. It can also affect dental health.

The adverse health effects from high ingestion of artificial sweeteners aren’t as widely reported, but experts do have some concerns.

In May 2023, the World Health Organization (WHO) issued a recommendation against using artificial sweeteners to control body weight due to concerns that long-term use could increase the risk of cardiovascular disease and type 2 diabetes.

David Cutler, MD, a family medicine physician at Providence Saint John’s Health Center in Santa Monica, CA, who wasn’t involved in the study, said there may be a number of other health effects from high usage of artificial sweeteners. Among them:

• effects on insulin resistance
• changes in gut microbiome
• effects on dental health

“The bottom line is that while [artificial sweeteners] are safer than [sugary beverages], they are not risk free,” Cutler told Healthline.

Ali shared similar concerns.

“Artificial sweeteners can have adverse effects, such as altering the gut microbiome, which can increase chronic inflammation,” he said. “They may also trigger insulin release in some patients, potentially leading to insulin resistance.”

Tips to reduce your sugar intake

Experts agree that weight loss programs should emphasize healthy diets and a daily exercise routine.

Healthy diets should consist of unprocessed foods such as fruits, vegetables, legumes, whole grains, nuts, seeds, eggs, and dairy products. A balanced diet should also be low in processed foods and sugar.

Long says that artificially sweeteners can be a bridge to help people wean off sugar-laden sodas.

“Obviously, drinking water is the best option — it’s hydrating and doesn’t contain the other stuff that artificially sweetened beverages do,” he told Healthline. “But it’s very hard for people to replace their juice or soda with water. So as an intermediate step, replacing caloric drinks with something sweet but calorie-free is certainly better than abandoning the effort and going back to regular soda.”

Kirkpatrick, however, said there may be some risks to this strategy. “This study shows that perhaps diet drinks can be an effective bridge for people trying to reduce sugar intake. My concern is that individuals may see this finding and consider diet colas to be a ‘healthy’ option,” she said.

“As a dietitian, I often find that it makes it harder for individuals to be able to reduce their sugar intake since [artificial sweeteners] are still delivering a high level of sweetness, potentially keeping cravings for sugar high,” she added.

Cutler argued that drinking artificially sweetened beverages can cause some people to consume more calories overall.

“Possible mechanisms for this are disruption of appetite regulation, meaning people eat more with the justification that they are no longer getting calories in their [artificially sweetened beverages]. And the sweet taste of [artificial sweetened beverages] may alter how the brain feels rewarded by eating,” he said.

Experts agreed that an overall healthy lifestyle is the ultimate goal.

“Overall, in terms of maintaining a healthy diet and lifestyle, I think you try to eat a variety of foods, not too much, ideally with everything in moderation,” Long said.

“There are multiple components to optimizing health span and preventing chronic disease. Diet, exercise, stress management, and sleep are all interconnected parts of a healthy lifestyle,” Kirkpatrick added.

“From a nutrition perspective, one of the simplest and most effective starting points is to keep foods as close to their natural state as possible,” she said. “This means limiting additives, cooking more at home, and prioritizing a variety of colorful plant foods, lean proteins, and healthy fats.”

Kirkpatrick noted that the best way to attain a healthy lifestyle differs from person to person.

“It’s important to remember that there is no one-size-fits-all approach. Individual needs, preferences, and health goals matter,” she said.