Stevia - How Safe Is It Really?

Chef Jeff's Weekly Health Update

"Due to the requests for my opinion on Stevia, I am re-running this update from earlier this year with a few additional comments. Stevia is a chemical that is derived from the leaves of the stevia shrub and has been used for years by South Americans to sweeten their yerba mate, a beverage similar to tea, and other stimulant beverages.

Stevioside, the main ingredient in stevia (the two terms are often used interchangeably), is virtually calorie-free and hundreds of times sweeter than table sugar. "So it appeals to many people as a natural alternative to artificial sweeteners," says Mark Blumenthal of the pro-herb American Botanical Council in Austin, Texas. 

So, is stevia safe to use as a sugar substitute or alternative? We don't know.

 Stevia has not yet been approved as a sugar substitute by the U.S. Food and Drug Administration (FDA). Therefore, it is sold in the USA as a dietary supplement, an unregulated industry. In Japan, manufacturers have used stevia for over 30 years, but the FDA has turned down three industry requests to use stevia in foods in the US.

Why hasn't the FDA approved stevia? "We don't have enough data to conclude that the use [in food] would be safe," the agency stated  in 1994. It is true that no reports of any adverse reactions have surfaced after 30 years of use in Japan. However, Douglas Kinghorn, professor of pharmacognosy (the study of drugs from plants) at the University of Illinois at Chicago notes "the Japanese don't consume large amounts of stevia." neither do I. But itn any event it beats hell out of sugar and is a great crossover sweetener.

Toxicologist Ryan Huxtable of the University of Arizona in Tucson also adds, "In the U.S., we like to go to extremes, so a significant number of people here might consume much greater amounts."

Dr. George Pauli, from the FDA's Office of Pre-Market Approvals which regulates food additives, says that stevia hasn't been tested the way food ingredients are generally tested to give assurance of safety. He admits that some tests have been done, but they are not ``strong enough to stand behind the safety of the product.''

Dan Richard, a representative of Now Foods, one of the largest sellers of stevia in the country, argues that stevia ''has no known side effects'' whereas aspartame -- an FDA-approved sugar substitute -- ``has a list of side effects.'' Stevia is a `great product (which has) been around for millennia.''

David Schardt, associate nutritionist for the Center For Science In the Public Interest, admits that the side effects of stevia are unknown, but there are concerns about using the product as a sweetener. ''Although there is no evidence of harm to people, laboratory studies of stevia have found potential cancer and reproductive-health problems,'' he stated. Realize that the US is not alone in its refusal to approve stevia. Neither Canada nor the European Union allow food companies to add the sweetener to their products. A scientific panel from the European Union, concerned about the potential toxicity of stevioside -- stevia's main ingredient - has declared it is ``not acceptable.'' In 1998, a United Nations expert panel came to essentially the same conclusion. Here are the specific concerns...

Reproductive problems.  Stevioside seems to affect the male reproductive organ system, European scientists concluded last year. When male rats were fed high doses of stevioside for 22 months, sperm production was reduced, the weight of seminal vesicles (which produce seminal fluid) declined, and there was an increase in cell proliferation in their testicles, which could cause infertility or other problems (A). And when female hamsters were fed large amounts of a derivative of stevioside called steviol, they had fewer and smaller offspring (B). Would  small amounts of stevia also cause reproductive problems? 
No one knows.

A. Yamada et al. Chronic toxicity study of dietary stevia extracts in F344 rats. J. Food Hyg Soc Japan 26169-183, 1985. B. Wasuntarawat et al. Developmental toxicity of steviol, a metabolite of stevioside, in the hamster. Drug Chem Toxicol 1998 May;

21(2)207-22. 

Cancer. In the laboratory, steviol can be converted into a mutagenic compound, which may promote cancer by causing mutations in the cells' genetic material (DNA). "We don't know if the conversion of stevioside to steviol to a mutagen happens in humans," says Huxtable. "It's probably a minor issue, but it clearly needs to be resolved." 

Energy metabolism.

Very large amounts of stevioside can interfere with the absorption of carbohydrates in animals and disrupt the conversion of food into energy within cells. "This may be of particular concern for children," says Huxtable. The FDA has also received reports of depression, anxiety, and hyperactivity resulting from the use of stevia. 

The bottom line, according to Schardt, is ``if you use stevia sparingly... it isn't a great threat to you.'' The FDA ``can't say it's safe or unsafe,'' Pauli acknowledged, but Schardt suggests that it might become a public health problem if it were approved as a sugar substitute.

``If stevia were marketed widely and used in diet sodas, it would be consumed by millions of people,'' he writes. ``That's why the government needs to require companies to do more - and better -- testing,'' Schardt concludes. So, is stevia a safe alternative to use? Is it a healthy substitute for sugar? No one knows for sure right now and there are some legitimate concerns about its safety.

The real question is why do people keep looking for a safe sugar substitute? The answers is because people want to cut back on their calories and to lose weight. So, is stevia or any other sugar substitute the real answer to this?

I do not think so.

Realize that even if stevia was approved, it would not really help. Since the early 70's the use of artificial sweeteners in the U.S. has risen by about 600 fold. In the same period, the average weight of the average American has risen. Now, about 57% of American are overweight. Additionally, the average caloric intake has also risen from about 1900 calories per day to about 2300 calories per day.

As you can see, the incredible rise in the use of artificial sweeteners has not helped reduce the weight and caloric intake of Americans. In fact, you may be inclined to say it has done the exact opposite. And, during the same period, the use of sugar has also risen dramatically. So, another real question, is why do we crave sugar (and sugar substitutes) so much? What can we do about our sweet tooth?

Having a sweet tooth is normal and natural for us. The problem isn't with our "sweet tooth", but how we satisfy it. You see, we "crave" sugar because unprocessed, unrefined complex carbohydrates (and the glucose that is derived from them) is our most efficient fuel and source of energy for our body. And, several of our organs, like the brain, and nervous system, can run only on the glucose that can be derived from these carbohydrates. The problem is that many of us have gotten used to satisfying this natural craving for complex carbohydrates by getting it in a highly concentrated and refined form that can create problems with our metabolisms and biochemistry. Another reason is that we eat diets that are either to low in or eliminate complex carbohydrates, and when we do, our body starts to crave its natural energy source. Also, many of us eat diets that are high in refined carbohydrates (bread, bagels, crackers, muffins, pasta). These products also create metabolic and biochemical problems and do not satisfy our need for natural unrefined carbohydrates along with the nutrients they provide. 

Refined carbohydrates and sugars are lacking in fiber and nutrients and can increase insulin levels, increase blood sugar levels, interfere with vitamin and mineral metabolism, increase our risks for cancer and in some, even increase excretion of calcium. Even highly refined "natural" ones (maple syrup, barley malt, rice syrup and even whole grain breads, bagels, pasta, and crackers) can create problems with our metabolism (and actually cause us to burn less fat during the day) 

The best source of complex carbohydrates is fresh fruit, veggies, and legumes. When we don't get in enough natural carbohydrates, we do crave them, and when we do crave them we often reach for them in a highly refined form to quickly satisfy the craving. So, the best course of action is to include plenty of fresh ripe fruit, veggies, legumes, and unrefined complex carbohydrates (like beans, peas, & squash) in our diets. And, whenever you feel that "sugar" craving coming on... understand why you have it and what your body is telling you. And then, satisfy it in the best way..... by reaching for some carbohydrates the natural way..... like having a delicious sweet and juicy apple instead. 

"An apple (or two) a day, keeps the sugar craving at bay." Have another great week, and remember... Your Health Is Your Greatest Wealth! "

In Health, Chef Jeff

Mike's comments:
The studies mentioned seem prejudged toward overkill, trying to make it look bad.  The sugar industry would probably like to see it go away and stay away.  I use it myself.  Rarely but I use it because I like some things sweetened like iced or hot herbal tea and may be in a restaurant and not want to use sugar or honey, both of which have significantly higher  impacts on the pancreas/glucose/insulin relationship.  Also, there are stevia recipe books available such as Stevia, by Rita DePuydt.