Monday, October 4, 2010

Feature Article: Artificial Sweeteners: A Lesser Of Two Evils?

          Artificial sweeteners, also known as non-nutritive sweeteners have been the subject of controversy since their inception in 1879.  A variety of myths and misconceptions concerning their health effects have been swirling around for decades.  The subject of this post is to answer some of the most common questions that I receive concerning non-nutritive sweeteners in my nutrition counseling practice. 

What are non-nutritive sweeteners?
            Non nutritive sweeteners are food additives that provide a sweet taste without providing caloric energy.  They have zero grams of carbohydrate, zero fat and zero protein.  The FDA has approved use of 5 non-nutritive sweeteners.
  • Aspartame- found in Equal, Nutrasweet and others.  Aspartame, gram for gram is 180 times sweeter than sugar.
  • Acesulfame-K- found in Sunett, Sweet One, is 200 times sweeter than sugar.
  • Saccharin- found in Sweet’N Low, is 300 times sweeter than sugar.
  • Sucralose- found in Splenda, is 600 times sweeter than sugar.
  • Neotame- does not have any brand names and is 7,000-13,000 times sweeter than sugar.
Are they safe?
            Despite popular belief, the FDA approved non-nutritive sweeteners are extremely well tested for safety.  These sweeteners have been tested at levels of consumption so high that a person could never attain them in everyday life, yet still produced no negative effects on health.  I recently read a review paper on all of the non-nutritive sweeteners and the summary finding was that they were not associated with any negative health outcome.  After reviewing the literature, I can say with confidence that these additives will not cause brain cancer, strokes, seizures, Alzheimer’s disease or any of the other maladies that people associate with them.

Does this mean I can use them all the time?
            This is where it gets a bit tricky.  I do not recommend the use of these sweeteners on an everyday basis.  Although they won’t cause you to die from cancer like everyone thinks, there are 2 major problems with them.

Problem #1 Non-nutritive sweeteners perpetuate cravings for sugar and refined carbohydrates.
            As any one of my clients will tell you, no matter what your health and fitness goals may be, a big part of getting there is to reduce your consumption of refined carbohydrates such as bread, pasta, white rice and sugar.  The good news is that when you limit these foods in the context of a stable blood sugar, cravings for them disappear after about 2 weeks.   If you are eating non-nutritive sweeteners on a daily basis, you’ll never get over your cravings for the refined carbs.  You will be hungry all the time.  This is a problem because any diet that involves feelings of deprivation and hunger will not work long term.

Problem #2 The Cephalic Response
            The second problem with the non-nutritive sweeteners gets a bit more technical.  We humans have something called the Cephalic Response.   If I was to put your favorite food in front of you, your eyes would see it, your nose would smell it and your body will actually release digestive enzymes before you even put a bite into your mouth!  Your body is anticipating consumption.  This is very likely happening with the non-nutritive sweeteners.  Your body thinks it’s getting something sweet so it releases insulin anyway.  This is the exact situation you are trying to avoid, since the resulting drop in blood sugar following an insulin surge will leave you hungry.  I have seen some papers that showed an association between non-nutritive sweetener use and increased hunger and food consumption.

Take Home Message
            In light of these two problems, I do not recommend non-nutritive sweeteners for everyday use.  However, once or twice a week, I believe that they are far less harmful than sugar.  At the end of the day, I can’t produce a single research paper that shows an association between non-nutritive sweeteners and any chronic disease.  On the other hand, I can produce dozens, if not hundreds of research papers that show an association between high glyemic carbohydrates such as sugar and chronic diseases such as heart disease, stroke, diabetes, cancer and possibly even Alzheimer’s disease.  In summary, non-nutritive sweeteners appear to be the lesser of two evils, but don’t go overboard.  Have a sugar free treat once or twice a week at the most.  But of course, stay away from sugar all the time!

Additional Questions
What about Stevia?
            Stevia is another non-nutritive sweetener that is produced from the leaves of a plant grown in South and Central America.   While Stevia’s producers say it is safe, the FDA has not done its own evaluation just yet.   The FDA initially agreed to the manufacturer’s safety findings and has allowed it to be used in a variety of products.  More recently, there have been some reports that Stevia may increase cancer risk, so the FDA is requiring more information on the safety of this sweetener.  Personally, I feel that Stevia has not been tested enough for me to recommend it to my clients.  I’d stay away from it until we learn more.

What about Sugar Alcohols?
            Sugar alcohols are compounds that taste sweet like sugar, but are not as easily broken down and absorbed as table sugar.  On food labels, they show up as xylitol, mannitol, erythritol, hydrogenated starch hydrolysates and sorbitol.  Sugar alcohols are found in nature in prunes and apricots.  Sugar alcohols generally have 50-70% of the sweetness of sugar.  They are cropping up in all sorts of sugar free items, particularly sugar free candy and ice cream.   The only problem I have seen regarding safety/side effects is that they will have a laxative effect when consumed in large quantities due to the fact that they are not completely absorbed.  Therefore, start with small amounts and see how you tolerate them.  Again, limit consumption of all non-nutritive sweeteners to once or twice per week.


Mike Alves said...

Hi Tom. Thanks for the blog post. Would you consider an article on protein powders, meal replacement shakes (powders or homemade one's like an oatmeal entree blended in the blender) for the random days on the run and smoothies?

Dr. Thomas Halton said...

Absolutely, that is in the works.