Are Artificial Sweeteners Bad for You?

Are artificial sweeteners bad for you

Updated 3.2020 Confession time! Many years ago, I put the pink stuff in my coffee and maybe snuck in a few diet sodas a day. Then I changed to the yellow stuff because it tasted better. Now I’m talking QUITE a few years ago so don’t delete this post!  In my defense, I started practicing nutrition over 20 years when we were still fat phobic. But then I started to realize all this fake sugar probably wasn’t so healthy. If you asked me why, I’d have said “it’s not natural. It can’t be healthy”. But I didn’t have any REAL explanations as to why artificial sweeteners may be bad for you. Despite the fact that artificial sweeteners have been deemed as safe by our regulating health bodies, recent studies have been suggesting otherwise. Read on to get the possible not-so-sweet story!

Is Artificial Sweetener Bad for You? | Martha McKittrick Nutrition

How much sugar do we eat a day?

The average American consumes approximately 22 teaspoons of sugar or 335 calories a day. Much of it is hidden in cereal, energy bars, yogurt, etc. I think we call all agree that excess amounts of added sugar (as compared to natural sugar found in fruit) is not healthy. Sugar has been linked to cardiovascular disease, elevated blood pressure, triglycerides, total cholesterol, and LDL (“bad”) cholesterol as well as visceral obesity,  non-alcoholic fatty liver disease, acne, and hyperuricemia. It’s also suggested that sugar may be associated with accelerated cognitive decline, inflammation and some cancers. However, the National Cancer Institute says “no studies have shown that eating sugar will make your cancer worse or that, if you stop eating sugar, your cancer will shrink or disappear”.

The newest dietary guidelines from the US Department of Agriculture recommends no more than 6 teaspoons/day for women and 9 teaspoons/day for men of added sugar. This adds up pretty quick – like one bottle of regular Snapple or regular soda!

Examples of added sugar include: agave sugar or nectar, apple juice concentrate, brown sugar, coconut sugar, corn syrup, fructose, high fructose corn syrup, honey, molasses, maple syrup, raw sugar, table sugar, powered sugar,  evaporated cane sugar, etc.
*note: pure honey  and pure maple syrup (without added ingredients)  may have a little nutritional edge over the others as they contain some antioxidants, but they are still considered added sugars.

What are artificial sweeteners?

Artificial sweeteners, also called sugar substitutes (or non-nutritive sweeteners), are used as sugar replacements.  They’re found in a variety of food and beverages marketed as “sugar-free” or “diet,” including soft drinks with reduced sugar content, baked goods, and many snack foods. Artificial sweeteners are used to help satisfy our sweet tooth – and/or control blood sugar – without sugar and its calories. They’re all sweeter than table sugar (sucrose) but contain few or no calories. Currently, about 1 in 4 American children and about 2 in 5 American adults use them on a regular basis and intake has increased by 200 percent in children and 54 percent in adults from 2000 to 2010. Reference

There are six artificial sweeteners are approved to be used as sweeteners in food.

6 artificial sweeteners approved by the FDA

Saccharin (e.g. Sweet n’Low)
Aspartame (e.g., NutraSweet® and Equal®)
Sucralose (e.g. Splenda®)
Acesulfame potassium, (also known as ACK, Sweet One®, and Sunett®)

*Stevia (Truvia® and PureVia®) and monk fruit are approved as food additives, not sweeteners.

sugar vs artificial sweetenerAnd even if you don’t consume artificial sweeteners knowingly, they’ve been found in drinking and surface water and groundwater aquifers. Many health experts call them emerging environmental pollutants. Reference

Are artificial sweeteners bad for you?

Artificial sweeteners have no calories or sugar so technically they shouldn’t cause weight gain or raise blood sugar. But is this really the case and can something that is artificial be healthy? The FDA says all six approved sweeteners are safe for human consumption. The approval process includes determination of probable intake, cumulative effect from all uses, and toxicology studies in animals. The FDA reviewed numerous safety studies on each sweetener, including studies to assess cancer risk. The results of these studies showed no evidence that these sweeteners cause cancer or pose any other threat to human health as long as consumed “in moderation”. That means no more than 23 packets a day of Splenda, Sweet One or Neotame, 45 packets a day of Sweet’N Low or 75 packets a day of Equal(unless you have PKI. Then you should avoid this 100%). This sounds a little more than “moderation” to me!

Despite the fact that these sweeteners have been deemed as safe by the FDA, their safety remains a hotly debated topic. The initial cause of concern was cancer risk. But in the recent years, there is increasing experimental and epidemiological evidence that low-calorie sweeteners promote metabolic dysfunction similar to that of regular sugar, despite the lack of calories. There now exists a body of evidence that animals chronically exposed to any of a range of low calorie sweeteners – including saccharin, sucralose, acesulfame potassium, aspartame, or the combination of erythritol  and aspartame – have exhibited one or more of the following conditions:
-increased food consumption
-lower post-prandial thermogenesis
-increased weight gain
-greater percent body fat
-decreased GLP-1 release during glucose tolerance testing
-significantly greater fasting glucose, glucose area under the curve during glucose tolerance testing, -and hyperinsulinemia. Reference: webinar

Keep in mind that the above studies were done in animals. However, recent studies suggest similar effects may occur in humans. More are needed to confirm this. But in the meantime, it certainly is food for thought.

Older research:

  • Cancer: The following information was taken from the National Cancer Institute:
    -Saccharin. In the 1970s, the FDA was going to ban saccharin based on the reports of a Canadian study that showed that saccharin was causing bladder cancer in rats.However as per the National Cancer Institute, human epidemiology studies (studies of patterns, causes, and control of diseases in groups of people) have shown no consistent evidence that saccharin is associated with bladder cancer incidence.
    -Aspartame was approved in 1981 by the FDA after numerous tests showed that it did not cause cancer or other adverse effects in laboratory animals. A 2005 study raised the possibility that very high doses of aspartame might cause lymphoma and leukemia in rats. But after reviewing the study, the FDA finds no reason to alter its previous conclusion that aspartame is safe as a general purpose sweetener in food. In 2006, NCI examined human data from the NIH-AARP Diet and Health Study of over half a million retirees. Increasing consumption of aspartame-containing beverages was not associated with the development of lymphoma, leukemia, or brain cancer. A 2013 review of epidemiologic evidence also found no consistent association between the use of aspartame and cancer risk.

More recent research:

  1. Alters gut bacteria: Did you know that you have 5 pounds of bacteria living in your body? The majority lives in your intestinal tract, and are also found in your urogenital tract, respiratory system and skin. It turns out that these little critters play an important role in health. 70% of our immune system comes from our gut. In addition to gastro-intestinal health, research is also linking gut bacteria to heart health, obesity, risk of diabetes, metabolic syndrome, osteoporosis, mental health, etc. While we are only in the toddler stage of research, we do know diet plays an important role in keeping gut bacteria in balance. Studies are suggesting that artificial sweeteners can have a negative effect on our gut microbiome. This imbalance of gut bacteria may lead to insulin resistance and weight gain. While these are intriguing studies, more research is needed to understand how this change in the gut microbiota affects our health. In addition, we don’t know what the ideal gut microbiome is. And many of the studies have been done in animals. We need to internal organsunderstand how this will affect humans.  Read my previous post on Top 8 Tips for Gut Health#1.This study by Eran Elinav et. al. show that consumption of the three most commonly used non-caloric artificial sweeteners — saccharin, sucralose and aspartame — directly induces a propensity for obesity and glucose intolerance in mice. These effects are mediated by changes in the composition and function of the intestinal microbiota; deleterious metabolic effects can be transferred to germ-free mice by fecal transplantation and can be abrogated by antibiotic treatment. The authors demonstrate that artificial sweeteners can induce dysbiosis and glucose intolerance in healthy human subjects, and suggest that it may be necessary to develop new nutritional strategies tailored to the individual and to variations in the gut microbiota.

    #2. This study was done with 6 artificial sweeteners (aspartame, sucralose, saccharine, neotame, advantame, and acesulfame potassium-k) and 10 sport supplements containing these artificial sweeteners. The bacteria found in the digestive system (eg, E. coli) had a toxic response when exposed to concentrations of only one mg/ml of the artificial sweeteners. “This is further evidence that consumption of artificial sweeteners adversely affects gut microbial activity which can cause a wide range of health issues.” But keep in mind this study was only done on bacteria, not humans. Researcher Ariel Kushmaro, a professor of microbial biotechnology at Ben-Gurion University says “we are not claiming that it’s toxic to human beings,” Kushmaro said, “we’re claiming that it might be toxic to the gut bacteria, and by that, will influence us.”#3. Since stevia is still relatively new to the market, not many studies have been done. But these studies (not done in humans)  suggests stevia may alter gut bacteria  study #1     study #2  
  2. Promotes metabolic syndrome and predisposes people to prediabetes and diabetes
    #1. This study was presented at the annual meeting of the Endocrine Society, 2018. It showed that consumption of low-calorie sweeteners could promote metabolic syndrome and predispose people to prediabetes and diabetes, particularly in individuals with obesity. Metabolic syndrome is a group of risk factors including high blood pressure, high blood sugar, unhealthy cholesterol levels and abdominal fat. It doubles the risk of blood vessel and heart disease, which can lead to heart attacks and strokes, and increases the risk of diabetes by three to five times. The study showed that sucralose (at a concentration equal to 4 cans of diet soda a day) promotes metabolic dysregulation, including fat cell genesis, dysregulation of response to insulin and glucose, inflammation, and increases in plasma triglycerides, particularly among those who are obese. Researcher Sabyasachi Sen, M.D., Associate Professor of Medicine at George Washington University in Washington, D.C. said “we think the effect is more pronounced in overweight and obese people rather than their normal weight counterparts because they have more insulin resistance and may have more glucose in their blood.”#2. Pase et al (2017) demonstrated mice fed sugar substitutes for 11 weeks had worsened glucose tolerance. Reference: Webinar:  Sugar vs substitutes: what does the research say?
  3. Allow more glucose to enter fat cells
    #1. This study was presented at the annual meeting of the Endocrine Society, 2017. Consumption of low-calorie sweeteners was associated with upregulation of gene expression for glucose transporters in experiments using human mesenchymal stromal cells and adipose tissue, according to new research.  The effect was strongest in individuals with obesity. Further and larger studies are called for, especially in individuals with diabetes and obesity, Dr. Sen said. “However, from our study, we believe that low-calorie sweeteners promote additional fat formation by allowing more glucose to enter the cells, and promote inflammation, which may be more detrimental to obese individuals.”#2. However this study showed conflicting resultsartificial sweeteners had no effect on blood sugarThe study authors looked at 29 randomized controlled trials. Those studies had a total of 741 participants. Most were healthy, 69 had type 2 diabetes, and the health status of 150 people was unknown. The review only included studies where the artificial sweetener was consumed without other foods and drinks containing calories. The study authors concluded that artificial sweeteners don’t affect blood sugar levels. Future studies are warranted to assess the health implications of frequent and chronic NNS consumption and elucidate the underlying biological mechanisms.

Artificial sweeteners: good or bad? Results of a large review

Now to make things even a little more confusing … There is an extensive body of evidence on artificial sweeteners, however much of it is conflicting. Recently, an enormous review, published in 2017 in Nutrition Journal pulled together data from 372 studies including 15 smaller systematic reviews. The authors organized the review by looking at the evidence for individual health effects and medical problems.

  •  They included 372 studies in their review, comprising 15 systematic reviews, 155 randomized controlled trials (RCTs), 23 non-randomized controlled trials, 57 cohort studies, 52 case-control studies, 28 cross sectional studies and 42 case series/case reports. Appetite and short term food intake, risk of cancer, risk of diabetes, risk of dental caries, weight gain and risk of obesity are the most investigated health outcomes were looked at in healthy subjects.
  • The results were conflicting and the researchers recommended further research to address the evidence gaps related to health effects of non-nutritive sweetener use. For a summary of the studies, read this article in Psychology Today.

What do the health governing organizations say about artificial sweeteners?

Academy of Nutrition and Dietetics:  Consumers can safely enjoy a range of nutritive and nonnutritive sweeteners when consumed within an eating plan that is guided by current federal nutrition recommendations, such as the Dietary Guidelines for Americans and the Dietary Reference Intakes, as well as individual health goals and personal preference. (2012)

A Scientific Statement from the American Heart Association and the American Diabetes Association:  The evidence reviewed suggests that when used judiciously, nonnutritive sweeteners could facilitate reductions in added sugars intake, thereby resulting in decreased total energy and weight loss/weight control, and promoting beneficial effects on related metabolic parameters. However, these potential benefits will not be fully realized if there is a compensatory increase in energy intake from other sources.  At this time, there are insufficient data to determine conclusively whether the use of nonnutritive sweeteners to displace caloric sweeteners in beverages and foods reduces added sugars or carbohydrate intakes, or benefits appetite, energy balance, body weight, or cardiometabolic risk factors.

*this recent review of long-term use of nonnutritive sweeteners that concluded that nonnutritive sweeteners  may not be helpful for weight loss and, in some studies, were associated with increased incidence of obesity, diabetes and heart disease. The authors found no long-term studies of stevia in particular to include in that review.

Bottom line:

Artificial sweeteners are approved as safe for human consumption by the FDA. Major governing health bodies agree they can be included as part of a diet that follows a heathy pattern. Many people have been using them for years and find them helpful in controlling blood sugar as well as possibly helping with weight control and have experienced no known health effects.

That being said, the science of nutrition is always changing. For example, for years we told people with high cholesterol to avoid eggs due to their cholesterol-raising effects. Science has now proven this to be inaccurate! We are just starting to learn how the gut microbiome affects our health and what role food, including artificial sweeteners, plays in altering it. This is the area I am most concerned about when it comes to artificial sweeteners. Our gut microbiome plays a role in diabetes, heart disease, body weight to name a few. I believe this will an important area of research in years to come.

The health effects of artificial sweeteners are inconclusive, with research showing mixed findings. adding cinnamon to coffeeFurther investigation following prolonged consumption of artificial sweeteners is required to better understand their role in human health. It’s also likely that artificial sweeteners will have variable effects on individual people due to effect of genes, individual metabolisms and gut microbiomes. So what does this mean?

My recommendations for sweeteners

My overall approach to nutrition has always been more of a moderate approach. I’m not an alarmist and don’t like to say you can NEVER have something. But that being said, I’m not a fan of added sugars in excess nor am I a fan of artificial sweeteners. I’d prefer we all limit our intake of added sugars and artificial sweeteners! But to answer the question – are artificial sweeteners bad for you?  As you probably guessed – there is no ONE answer. You’ll have to weight pros and cons.

My recommendations regarding sugar and sugar substitutes:

  • Cut down on all added sugars, especially from sugar sweetened beverages, sugary snacks and high fructose corn syrup. There are strong links between added sugar and numerous health conditions. This is true for everyone, but especially important for those people who are obese/overweight, have diabetes, pancreatitis, fatty liver, elevated triglycerides, high blood pressure. We were not evolved to consume sugary food and drinks!
  • This doesn’t mean you can never have added sugar. So just aim for sugary foods on occasion. For example, a drizzle of maple syrup on oatmeal or honey on Greek yogurt is fine! If you have diabetes, pay attention to what this does to your blood sugar.
  • In my experience, as you consume less sugar, your cravings will subside.
  • Which is best – real sugar or artificial sweeteners? My first answer would be NEITHER. But if I had to pick one, I’d say to have a little of the real thing (maple syrup, honey, brown sugar, etc) over an artificial sweetener like Splenda, Sweet N’Low etc. The key here is SMALL portion – like 1 tsp sugar in coffee.
  • If you have elevated blood sugar or are on a low carb diet and  don’t want to give up artificial sweeteners, my advice would be moderation. My real concern is for those people who have multiple servings a day (diet drinks, several artificial sweeteners to coffee, diet yogurt, etc. ) My personal suggestion would be to cap it out at 2 servings a day max.
  • Try not to get your kids consuming diet products
  • Stevia, monk fruit  or Swerve may be your best bet if you need to use a sugar substitute. But they keep in mind they are new to the market and have not been well studied. As noted above, some studies are suggesting stevia has a negative effect on gut bacteria.  Stay tuned for more research.

I’d love to hear what kind of sweeteners you use!


Additional references: 

Trends in Endocrinology & Metabolism, July 2018, Vol. 29, No. 7

How Non-nutritive Sweeteners Influence Hormones and Health by Kristina I. Rother et al

Metabolic Effects of Non-Nutritive Sweeteners





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