I have long planned to do an in-depth study of the research of the individual sweeteners. I am aware of some of it, and some general issues with different ones, but I am by no means an expert. Nevertheless, here are my current thoughts on the subject.
The fact of the matter is that if we all ate only fresh foods with no additives such as texturizers, preservatives, colors, sweeteners, etc, we would probably all be healthier. Interestingly, I have noticed both in myself and in others, that as we eat in ways that are aimed at improving our health we tend to gradually move to a more "pure" way of eating, and gain more interest in where our food comes from and what it is doing for us. This seems to come naturally and without a lot of extra effort. However, the fact is that most of us consume some foods which are processed to some extent.
So what do very small amounts of these chemicals do to our bodies over a long period of time? The fact is that we just don't know, nor is there any way to really test it. The FDA and similar regulators have had to be content with shorter studies using quite a lot of the substance. Most of the artificial sweeteners are several hundred times sweeter than sugar, so only small amounts are used as food additives. However, these and other chemicals could have effects with longer exposure of small amounts.
I have always found it interesting that people are more suspicious of sugar substitutes than other food additives. For example, when a study comes out showing a negative effect of diet soda, the conclusion is often that it must be the sweetener causing the problem, rather than any of the many other chemicals in a typical diet soda.
People often ask me specifically about stevia, which is made from the leaves of a plant which has been used for at least centuries for its sweetness. It's somewhat logical to conclude that substances such as this must be "safer", but unfortunately I don't think we have evidence of that. After all, herbs that were used in ancient times to help heal people have been used in modern times as the basis for powerful drugs, even chemotherapy agents, which can have very serious side effects. We aren't chewing on stevia leaves these days, but consuming a very refined product, so I don't jump to the conclusion that it is necessarily better than other sweeteners.
Sometimes people will insist that a little sugar is better than an artificial sweetener. My opinion is that it depends on how well your body processes sugar. For me, anything that sends my blood sugar up is probably not a good thing, and I prefer to have a little something with a sugar substitute, which satisfies the urge for something sweet without sending my body off track. But I have admiration for people who forego all sweet foods -- I'm not there yet!
Photo © Sanja Gjenero