Diet cola, sugar-free candy, even cookies from the bakery – many products contain artificial sweeteners these days. As more people turn to low-carb, high-protein primary diets as a form of good health, artificial sweeteners have gained widespread popularity, replacing sugar in more types of food than ever before.

But are artificial sweeteners bad for your health?

Before considering the question, the first thing to ask yourself is whether or not artificial sweetener is necessary in the foods you choose to eat. While Diet Pepsi outperforms regular Pepsi, nothing beats water in terms of old-fashioned hydration. And those sugar-free candies? Do they really add nutritional value to your diet?

But every now and then the craving gets too strong, the sweet tooth takes over. Artificial sweeteners have provided an alternative to sweets without adding the unnecessary carbohydrates found in typical sweets. Below are four of the most common artificial sweeteners and an explanation of whether they are healthy or harmful.

1) saccharin

Street Name: Sweet ‘n Low

This is the oldest artificial sweetener in the book. It has been around for almost 100 years! Originally used as a substitute for diabetics, saccharin was the solid staple of the artificial sugar industry for most of those 100 years. But in the 1970s, tests were conducted on animals that resulted in various cancers (uterus, skin, bladder) associated with the artificial sweetener. The USDA placed a “hazardous to your health” label on the substance and left it alone. Fast forward to 2000, more studies showed the original studies were inconclusive, the “dangerous” label was removed, and saccharin was upgraded from an unhealthy artificial sweetener to a questionable artificial sweetener. Of the many options, saccharin appears to have the most risk, especially for pregnant women, as the substance is transferred to the unborn fetus. Also, many people avoid saccharin simply because the original source is oil.

2) aspartame

Street Name: Equal, NutraSweet

Aspartame was the “healthy” artificial sweetener alternative to saccharin. It is a combination of phenylalanine and aspartic acid (amino acids) with methanol. It was a diet soda favorite for years, although many people dislike its distinctive taste.

So is aspartame a healthy artificial sweetener? Twenty-six FDA studies suggest yes, but there are still some that have reservations. Aspartame has been shown to cause problems for people who do not metabolize phenylalanine at a normal rate. It has also been shown to cause complications in people with liver disease and (again) in pregnant women.

3) sucralose

Street Name: Splenda

The newest favorite of the artificial sweetener crowd, sucralose is actually made from real sugar. The sugar is chemically altered to form the artificial sweetener, the hydrogen and oxygen components are exchanged with chlorine molecules. This removes the caloric content of the sugar and what is left is the artificial sweetener sucralose, which is approximately 600 times sweeter than the actual substance.

Sucralose came on the scene in 1998, so not as much research has been done to test whether the artificial sweetener is healthy or harmful, but so far all the research seems to suggest that there are no major harmful effects. New studies are published every month, although nothing has conclusively shown that sucralose is a harmful artificial sweetener. He appears to be the winner of the three mentioned so far. Although some people claim to have allergic reactions to the sweetener. It is always advisable to test the product before jumping in completely (try a slice of fake cake, not all of it).

4) Stevia

Street Name: Stevia

Stevia is the natural alternative; many claim that it is the healthiest artificial sweetener. Stevia is a real plant, native to Paraguay, the sweetener usually comes in the form of a powdered extract. There are no known harmful effects of Stevia. One drawback (depending on who you ask) is Stevia’s distinctive flavor. Many claim that it has an aftertaste that ruins the effect of sweetness.

Ultimately, the decision is yours. Optimal health does not require artificial sweeteners (healthy or otherwise) as an essential part of the diet, but artificial sweeteners provide the alternative for the person with the enduring sweet tooth.