WHO (World Health Organization), the United Nations’ health agency, advises that most people should not use non-sugar sweeteners to replace sugar in foods (UN News, May 15, 2023). They report that artificial sweeteners:
• have not been shown to help people lose body fat long-term (Front Nutr, Jan 7, 2021;7:598340)
• increase hunger so people may eat more and gain weight (Cell Metabolism, July 12, 2016;4(1):75-90)
• may increase risk for diabetes, heart attacks and premature death (Nature Medicine, Feb 27, 2023(3);710–718)
• do not supply any necessary nutrients.

The WHO admits that these guidelines may draw controversy because most of the studies they quote are studies of “association”, not of “cause-and-effect.” Almost all of the studies showing weight loss with artificial sweeteners are short term and so have not shown long-term weight loss. The WHO recommendations did not mention artificial sweeteners in toothpastes, skin creams or medications, and did not include low-calorie sugars or sugar alcohols that are made from sugar.

Definition of Artificial Sweeteners
Artificial-sugar sweeteners include both natural and artificial sweeteners packaged by themselves or added to manufactured foods and beverages. Artificial sweeteners that have been approved by the FDA include Aspartame (Equal or NutraSweet), Acesulfame potassium, Neotame, Saccharin (Sweet ‘N Low, Sweet Twin and Sugar Twin), Sucralose (Splenda, Equal), and Advantame. Sugar alcohols, such as sorbitol, xylitol, lactitol, mannitol, erythritol, and maltitol, sweeten with far fewer calories than sugars but can be hard to digest. Extracts from intensely-sweet plants such as stevia or monk fruit are also used as sugar substitutes.

Some Artificial Sweeteners May Harm You By Changing Gut Bacteria
Artificial sweeteners may increase risk for diabetes and weight gain by changing the bacteria in your colon (Nature, Oct 9, 2014;514(7521):181-6; Cell Metab, Nov 4, 2014;20(5):701-3). You have more than 100 trillion bacteria in your colon, and some are healthful while others can harm you. Some types of bacteria can turn on your immune system to cause inflammation that increases risk for heart attacks, dementia, auto-immune diseases and certain cancers (J Alzheimers Dis, 2017;58:1-15). As far as I know, only saccharin, sucralose and stevia have been shown specifically to change the composition of the gut microbiome, but others may have the same effect. Researchers followed 104,760 participants and found that people who drink large amounts of either sugared drinks or artificially sweetened beverages are at increased risk for developing new heart disease such as stroke, transient ischemic attacks (TIAs), heart attacks or acute coronary syndrome (J Am Coll of Cardiol, Nov 2020;76(18):2175).

My Recommendations
Sugared drinks cause high rises in blood sugar, much higher than the rise in blood sugar from the same amount of sugar in solid food, and artificial sweeteners have not been shown to be effective in long-term weight control or disease prevention. On the basis of research data available today, I recommend avoiding or restricting foods and drinks that have either added sugars or artificial sweeteners. Sugared drinks may be useful during prolonged, vigorous exercise, but at all other times, I recommend that you drink water to quench your thirst. Unsweetened coffee and tea appear to be safe also.

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