It’s one of the most frequently asked questions when it comes to health, blood glucose (blood sugar), and weight control: should you use sugar substitutes, aka, artificial sweeteners, low-calorie sweeteners, or non-nutritive sweeteners? Are they safe? Can they help you lose weight or reduce your blood sugar?
There have been decades of research on the safety of low-calorie sweeteners (LCSs) and whether they can help people lose weight or more easily achieve glucose control.
The research has been mixed, some positive and some negative. The truth is that the equation for a healthy eating pattern is one that does not focus solely on any one food or food product. Moderation is key.
And when it comes to losing and controlling weight, reducing calories from sugar and refined carbohydrates can help people who have diabetes or are overweight to lose weight and reduce blood sugars. So if switching from using sugar or regularly sweetened beverages, such as soda, to packets of LCS or diet beverages helps you control your weight and improve your blood sugar, then you may want to consider them.
For those of you who are skeptics of LCS becoming educated on the subject and weighing the pros and cons can help you to make good choices. Being overweight and having uncontrolled diabetes is a threat to your health and it may be advantageous to use products that help you reach your goals.
Many studies suggest that people who use LCS are able to lose weight easier, maintain a healthier weight, and control blood sugar levels. Hope Warshaw, MMSc, RD, CDE, BC-ADM, weighs in as an expert on the topic.
Some studies suggest that LCS promote overeating and eventually weight gain whereas others show when LCS are used as part of a healthy eating and lifestyle plan and can help control weight. Where does the truth lie?
Before looking at individual studies, here’s the bottom line. In viewing the body of research on LCS and body weight, many health associations and experts agree with the conclusions from a Scientific Statement from the American Diabetes Association and American Heart Association:
LCS are not a magic bullet for weight loss, but can be one of many tools you can use as part of a complete weight control plan. LCS can help people lower their calorie intake if they don’t replace the saved calories with calories from other foods.
There have been some conflicting studies but even more so conflicting headlines. To the research on LCS and weight control: A number of the headlines about LCS, and more specifically diet beverages that contain one or more LCS, have emanated from so-called observational studies. These studies review vast amounts of data from studies, which observe a large group of people and follow myriad lifestyle factors.
These studies can make observations but can’t confirm cause and effect, for instance, that LCS and/or diet beverages cause weight gain. The reality is that many other factors in a person’s food choices and lifestyle can cause weight gain. In a 2013 analysis by Pereira of a number of these observational studies, he concluded that people at risk of weight gain, obesity, and type 2 diabetes (T2D) may be more likely to increase their intake of diet beverages in an attempt to reduce their risk of diabetes and weight-related diseases.
A few randomized controlled trials (RCT) have been completed, which show that LCS (particularly when diet beverages replace sugar-sweetened beverages (SSB)) can help people lose a small amount of weight. RCTs are considered the gold-standard type of study in which researchers compare a control against one or more study groups to determine the impact of some change.
Peters and fellow researchers conducted a 12-week weight control program in about 300 men and women. The study group was instructed to drink 24 ounces per day of diet beverages (any type) and the control was to drink 24 ounces of water per day only.
Results showed the diet beverage group lost an average of 13 pounds or 44 percent more than the control group subjects who lost an average of 9 pounds.
Another RCT by Tate and fellow researchers looked at over 300 overweight adults over six months. The diet beverage and water groups substituted at least 2 servings per day of their SSB for a diet beverage or water. After six months the diet beverage drinkers were more likely to reach a 5 percent weight loss than the water drinkers.
One other study from the well-known National Weight Control Registry a registry of more than 10,000 people who have lost at least 30 pounds and kept it off for at least one year, looked at the consumption of LCS sweetened beverages in over 400 hundred people for seven years. It found 53 percent of participants regularly drank diet beverages and 10 percent regularly used SSB. Nearly 80 percent of participants reported that diet beverages helped them control their calorie intake.
Last but not least, a meta-analysis (analysis of many studies) published in 2014 by Miller and Perez found that LCS reduced body weight compared to placebo and modestly, but significantly reduced body mass index, fat mass, and waist circumference. In an editorial accompanying this publication, James Hill, PhD, a well-respected obesity researcher stated, “It means that LCS seem to be doing exactly what they were designed to do: helping reduce total energy intake while providing the sweet taste we value…You can confidently use this tool [LCS] without worrying that you might be unintentionally hurting your weight-management efforts.”
Does one type of low-calorie sweetener impact weight differently than another?
There is no research to show this. Today, diet drinks are most often sweetened with aspartame (canned and bottled drinks), aspartame and saccharin (fountain soft drinks), aspartame and acesulfame-K, or sucralose. One reason beverage manufacturers may use a blend of LCSs is to take advantage of the different taste profiles of the different LCS to improve overall taste of the product.
What does research conclude about LCS and cravings and increasing appetite for sugary foods and sweets?
This has been another area of contention regarding LCS. The notion seems to be that because LCS are sweeter than sugar they overstimulate sweet taste receptors and cause sweet cravings which lead people to overeat and gain weight.
Several studies refute this notion. For instance, Antenucci and Hayes recruited over 400 people for a series of taste tests. Participants drank between 12 and 15 separate samples containing calorie-containing sweeteners as well as various concentrations of several LCS. Study participants rated the perceived sweetness of each sample. The results showed that participants perceived the sweetness of LCS at lower concentrations than the calorie-containing sweeteners. The researchers concluded that the results don’t support the claim that LCS over-stimulate peoples’ sweet taste receptors.
In addition, three of the studies previously detailed include findings to help answer this question. Peters showed the hunger ratings at 12 weeks increased slightly in the water group and declined slightly in the diet beverage group which resulted in significantly less hunger. An additional analysis of the Tate study by Piernas showed that while both the water and diet beverage drinkers reduced total calories and added sugars intake, the diet beverage group reduced their consumption of desserts more. The researchers conjectured that perhaps diet drinks satisfy the desire for something sweet. The NWCR study showed that nearly 80 percent of participants said that diet beverages helped them control their calorie intake.
Bottom Line: Rather than increasing cravings, appetite, and hunger, in actuality LCS (either as a sugar substitute or food and beverage), may satisfy people’s cravings for sweets and tamp down their hunger.
Is it possible for low-calorie sweeteners to affect the gut microbiome in a manner that can cause rises in glucose levels?
The gut microbiome is the large variety of microorganisms that live in the digestive tracts (the intestines) of animals and humans. Research in this area is accumulating and increasing. The thinking is that maintaining a healthy gut microbiome can play a role in health, disease prevention and maintaining a healthy weight.
The study by Suez and fellow researchers published in Nature captured a lot of media attention and made several very broad brushstroke conclusions about the use of all LCS when, in reality, the majority of the sub-studies in the paper reported focused on saccharin and a number of them were conducted in mice. It’s important to note that, although LCS are in the same category, they are different in origin, composition and how they’re metabolized. This was a very complex paper with many sub-studies within. At this point some of the key study results have been challenged by respected experts. As is true with a lot of research, additional well-conducted studies will need to be done to further prove this relationship.
The findings in this study that aspartame and sucralose, the low-calorie sweeteners in greatest use, raise glucose levels don’t concur with the existing body of research. It’s worth noting that to be approved by FDA as a food additive and for use by people with diabetes (which they are), research submitted to the FDA for approval must include the studies about the impact of the LCS on glucose levels. Research submitted to FDA for approval as well as additional research in the ensuing years after approval doesn’t concur. Overall, studies, conducted over the past few decades, show that neither aspartame nor sucralose significantly change the gut microbiome or raise blood glucose levels.
Most of the animal and human sub-studies reported in the Nature study focused on the impact of saccharin on glucose control. Of interest to people with diabetes is that saccharin has been in use for more than 100 years and for many years was the only choice available. To date there are a few animal studies which indicate saccharin in high doses may change the gut microbiome. Data from human studies on this topic are insufficient and less clear.
Bottom Line: Further research is important, but a dramatic impact of even moderate saccharin use on the gut microbiome or glucose levels appears highly unlikely.
What are the recommendations about LCS from the American Diabetes Association (ADA) and other organizations?
In November 2013, the ADA published an update to their nutrition recommendations for adults with diabetes. In this position statement, which reviewed many nutrition related topics, the ADA statement reads: “Use of nonnutritive sweeteners [LCS] has the potential to reduce overall calorie and carbohydrate intake if substituted for caloric sweeteners without compensation by intake of additional calories from other sources.”
Regarding the impact of LCS on glucose levels, the ADA concluded in these nutrition recommendations that existing research shows that LCS don’t cause a glucose rise unless the LCS is consumed in a food or beverage with other calorie containing ingredients. For example, that would be a yogurt or hot cocoa sweetened with an LCS. In contrast, diet beverages generally contain no calories.
Bottom Line: LCS don’t cause a glucose rise unless the LCS is consumed in a food or beverage with other calorie containing ingredients.
How much LCS do people in general and people with diabetes specifically consume?
When it comes to “safe” amounts of LCS to consume research shows that people, on average, consume nowhere close to what is called the Acceptable Daily Intake (ADI). This includes people with diabetes, who may be the highest consumers of LCS. ADI is defined by FDA and other regulatory agencies around the world as the amount of an LCS that a person can consume every day of their life with no safety concerns. The ADI is based on the wide range of animal studies required for approval and is based on a one hundred fold safety factor from what’s called the highest no adverse effect level.
Let’s look at aspartame for an example. The FDA ADI for aspartame is 50 mg/kg of body weight/day. This amount would be equal to using 97 packets of an aspartame-containing LCS each day over a person’s lifetime. Yet the Estimated Daily Intake (EDI) for aspartame was found to be 6 percent of ADI in the general adult population. EDI is defined as an estimation of the amount of the ingredient consumed if it were substituted for sugar in 100 percent of all possible foods and beverages.
The FDA requires extensive research on LCS prior to allowing LCS on the market. Generally speaking, LCS are approved for use by the entire general population. This includes children, pregnant and breastfeeding woman and people with diabetes.
What is useful information for a person who is overweight and at risk for Type 2 diabetes (T2D) or someone with T2D regarding the most important actions they can take regarding their eating plan and long term health?
It’s clear from the research and the nutrition recommendations from the ADA that the most important actions a person at risk of T2D (prediabetes) or with T2D can do to prevent or slow the diagnosis (of prediabetes) or slow the progression of T2D at or just after diagnosis is to lose about 5 or 7 percent of initial body weight and keep off as much of that weight as possible—a tall task for sure!
This should be achieved by eating fewer calories, choosing healthy foods, and being physically active (this includes aerobic activity, resistance training and reducing sedentary behavior). In addition, it’s critical that people get and keep their glucose, blood pressure and blood lipids, under control initially and over time. Hitting these targets or those that you and your provider decide on can give you your best shot at staying healthy and minimizing complications over time. Today we know control of diabetes is more than just controlling blood glucose levels.
As for the use of LCS, whether to replace sugar in hot or cold beverages or in foods and beverage, my recommendation is to take advantage of these products to support your efforts to lose weight and keep those pounds off and to help you consume fewer grams of less healthy carbohydrates (fewer refined grains, sweets, and sugary foods) and added sugars, particularly from beverages.
Bottom Line: Go beyond the headlines! Be sure to read the details of any new study on LCS and fit the new findings from that study into the existing body of research. Keep in mind that LCS have been studied for decades and the ones that are approved for use in the U.S. and around the globe have gone through significant regulatory scrutiny prior to coming to market. Plus, review doesn’t end there. Regulatory agencies around the globe continue to review the research and their use over time.
Pereira MA. Diet Beverages and the risk of obesity, diabetes and CVD: A review of the evidence. Nutr Rev. 2013;71(7):433-440.
Peters JC, et al. The effects of water and non-nutritive sweetened beverages on weight loss during a 12-week weight loss treatment program. Obesity Journal. 2014;22(6):1415-21. (Link to article: http://anschutz.new-media-release.com/study/downloads/oby20737_NNS_study.pdf)
Tate D, et al. Replacing caloric beverages with water or diet beverages for weight loss in adults: the main result of the Choose Healthy Options Consciously Everyday (CHOICE) randomized control trial. American Journal of Clinical Nutrition. 2012;95:555-563. (Abstract)
Catenacci V, Pan Z, et al: Low/No Calorie Sweetened Beverage Consumption in National Weight Control Registry. Obesity. e-pub: http://onlinelibrary.wiley.com/doi/10.1002/oby.20834/full
Miller PE, Perez V: Low-calorie sweeteners and body weight and composition: a meta-analysis of randomized controlled trials and prospective cohort studies. American Journal of Clinical Nutrition. 2014.
Suez J, Korem T, et al. Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Nature, 2014.