SPOKANE, Wash. -- We know that too much sugar is bad for us.

According to the American Heart Association, it has been linked to heart disease, liver disease and diabetes.

Now that the holidays are over many people are looking to clean up their diets. But marketing hype can make it difficult to know which alternative sweeteners are the best to buy. Studies can also complicate the situation.

In 2010, the Cancer Research Journal found that fructose found in high-fructose corn syrup, agave, honey and even in fruit, feeds some types of cancer.

So now what?

KREM 2 checked in with Dr. Glen Duncan who is a Professor at Washington State University, Elson S. Floyd College of Medicine and Dr. Anthony Balduzzi, a Naturopathic Physician and founder of The Fit Father Project, to find out which sweeteners are safe and have the most health benefits.

Duncan said it is hard to believe or understand what you read and hear because robust data is published every day. But the fact of the matter is, he said, you cannot establish a cause of a disease with just one single study or patient. Scientists are interested in the hundredth study. A single data point is meaningless.

“There are a lot of factors that go into establishing causality. To say that you have established a causal link with one single paper is ludicrous,” said Duncan.

Duncan wants people to know food science is not perfect because it is difficult to measure someone’s lifestyle in the real world. Researchers can manipulate every single aspect of an animal’s environment by controlling their diet and putting an exercise wheel in their cage. But it is impossible to do that with people. Even a patient with the best of intentions will underreport the food they eat, over report their exercise and miss document by accident.

“The problem nutrition research faces is a huge problem with the validity of the data. The fact of the matter is it’s not easy to measure habitual diet, there is no gold standard method," he explained.

This is why you will read things like “the association between” artificial sweetener and cancer or dementia. At this point, there is no body of evidence linking an artificial sweetener to a specific condition. He said there maybe a causal link to artificial sweeteners but the science to prove it is not good enough yet.

“When you look at the body of literature you are looking at cross-sectional settings. And observational studies. those are one type of study and again they contribute to that picture of causality but they cannot make a causal case. There are very few randomized controlled trials in that mix. The whole body of evidence linking an artificial sweetener to some outcome of interest is very problematic. There may be a true causal link but we are not there. The science is not that good enough,” Duncan said.

Some people do report headaches or generally feeling unwell after ingesting anything containing artificial sweetener. Balduzzi said most of his patients have a sense artificial sweeteners cannot be good for their bodies because they are not natural.

“The hidden dangers of artificial sweeteners that go beyond the lack of calories. That is the thing, people make the association this has zero calories, it has to be good for me,” Balduzzi said.

He is excited about recent evidence published in the International Journal of Science. This finding explains the bloated or uncomfortable feeling his patients may have after eating artificial sweeteners. It shows that artificial sweeteners impact and harm the good bacteria in our gut that is important to good health. Balduzzi claims this could be the evidence linking artificial sweeteners to health conditions including cancer and diabetes over the next five to ten years. One of the biggest things that we are learning more about these days is the importance of gut health. Medical professionals are talking about that everywhere.

“The field of looking at the impact of different foods on gut flora so new and exciting and we are learning a ton. We are learning how important gut flora is in our overall health," he said. "The research is getting compiled and we are going to see a lot more of this over the next five to 10 years.”

He shared his list of the best and worst non-calorie sweeteners:

Worst Artificial Zero Calorie Sweeteners:

  • Aspartame (Equal, NutraSweet, NatraTaste Blue)
  • Sucralose (Splenda)
  • Acesulfame K (ACE K, Sunette, Equal Spoonful, Sweet One, Sweet ‘n Safe)
  • Saccharin (Sweet ‘N Low, Sweet Twin)

Best Natural Zero Calorie Sweeteners:

  • Stevia (extracted from the leaves of the stevia plant)
  • Erythritol (occurs naturally in some fruit and fermented foods)
  • Monk Fruit

Both Duncan and Balduzzi said people need to know there is much more to a food beyond what the nutrition label says and to eat all sweeteners in moderation. A Diet Coke will not kill you but drinking it every day for years may.