Artificial Sweeteners and Weight

As a former “diet soda addict,” I was really interested in reviewing artificial sweeteners and how they may help or hurt weight loss!

The first diet soda was designed in the 1950s for diabetics. Diet sodas and low sugar foods with artificial sweeteners have exploded in popularity over the last 30+ years. Offering the sweet taste that many love without any calories, artificial sweeteners seemed like such a promising option to help people lose weight.  While replacing sugar with calorie free sweeteners sounds like a great idea, the bottom line is that there is not much evidence that it can help people lose weight.

Currently the FDA has approved five artificial sweeteners: saccharin, acesulfame, aspartame, neotame, and sucralose. The FDA also has approved one natural low-calorie sweetener, stevia. Some additional sugar substitutes “generally regarded as safe (GRAS)” by FDA include monk fruit extract and sugar alcohols (erythritol, sorbitol and xylitol).  How the human body and brain respond to these sweeteners is very complex. Some observational studies link artificial sweeteners to weight gain, but evidence is mixed.  However, a few controlled studies suggest that artificially sweetened drinks do not cause weight gain.

Some proposed mechanisms for potential weight gain with artificial sweetener consumption include:

• Increase in appetite hormones leading to over-hunger,
• Alteration of taste buds: sugar substitutes are much sweeter than table sugar and this can lead to a limited tolerance for more complex and less sweet foods,
• Triggering an intense dopamine response leading to over-desire for sweet foods,
• Increase in insulin by some of the sweeteners, which can lead to weight gain and prevent fat burning,
• Unfavorable alterations in gut microbiome,
• False assurance that it is ok to get calories from other unhealthy options due to calorie restriction with artificial sweeteners.

There are correlational studies that show a potential link with artificial sweeteners consumption and the following (**Important note-correlation does not imply causation!)

• Increased risk of metabolic syndrome and diabetes,
• Increased risk of high blood pressure,
• Increased risk of stroke,
• Increased risk of chronic kidney disease,
• Alteration in gut bacteria.

If you want to try a sugar substitute, my top three recommendations would be stevia, erythritol and monkfruit. 

Stevia is derived from the leaves of a South American plant related to the sunflower.  The active sweet compounds are called stevia glycosides and are defined as GRAS. It has no calories or carbs, does not seem to impact insulin or blood sugar, and appears to be safe. However, it has a somewhat bitter taste and has not been around long enough for long-term health data.

Erythritol is made from fermented corn and is a sugar alcohol. It is only partially absorbed by the digestive tract and is also classified as GRAS by the FDA.  It has few carbs and calories and does not appear to impact blood sugar or insulin. It tends to work well in baking and is tolerated by most. However, for some it can cause bloating, diarrhea, and gas.

Monk fruit is a newer substitute but has been long used in teas and soups in eastern medicine.  The sweetness comes from non-caloric mogrosides that can replace sugar.  The FDA ruled monk fruit as GRAS.  It does not appear to raise insulin or blood sugar and is very sweet, so only a little is needed.  However, it is more expensive, and it is often mixed with other fillers and sweeteners.

While there is conflicting evidence about use of artificial sweeteners with weight loss and heath consequences, they do not add any nutritional value to your diet.  Carefully consider whether you want to include sweeteners in your life.  For some, moderation of sugar substitutes can make low carb diets more sustainable.  However, for others it may be best to avoid them all together.  The effects really do seem to vary from person to person.  If you want to use substitutes I would recommend doing so while journaling.  If you notice bloating, increase in appetite, or plateauing, it may make sense to evaluate if your artificial sweetener or sugar substitute is getting in the way of reaching your weight loss goals.

DISCLAIMER: Sarah Smith MD is a medical doctor, but she is not your doctor, and she is not offering medical advice on this website. If you are in need of professional advice or medical care, you must seek out the services of your own doctor or health care professional.