Is Stevia Safe to Use?

Medically reviewed by Melissa Rifkin, MS, RD, CDN

Eating too much sugar has been linked to an increased risk of heart disease, stroke, and some types of cancer. To cut back on sugar, some people replace it with low-calorie artificial sweeteners, plant-based natural sweeteners, or sugar alcohols. The goal is to have sweet-tasting foods with fewer calories and a reduced impact on blood sugar levels.

One popular alternative is stevia. This plant-based, zero-calorie sweetener won't spike blood sugar levels, and while the Food and Drug Administration (FDA) deems it safe, there are some cautions and controversies to know about. Here are the details you need to know before you make the switch.

Where Does Stevia Come From?

Stevia is a shrub that originated in South America. Its leaves contain compounds called steviol glycosides, which have a sweet taste. Glycosides are extracted and made into low-calorie sweeteners, which come in liquid, tablet, and powder forms.

The first stevia-based sweetener was created in Japan in the 1970s. In the U.S., the FDA approved the use of stevia as a dietary ingredient in 1995.

Stevia-based sweeteners are 200 to 400 times sweeter than sugar. Plus, a very small amount is needed to provide a sweet flavor. Because of this, stevia glycosides are mixed with other ingredients, such as dextrose, inulin, or erythritol, to bulk up the quantity. This allows stevia to be made into tablets or to fill up sugar packets.

Studies show that stevia also does not impact insulin or blood sugar levels as sugar does. This is important since insulin resistance is linked to type 2 diabetes, fatty liver disease, and some types of cancer. Stevia also has anti-inflammatory effects and contains some antioxidants.

Is Stevia Safe?

Stevia is a popular sugar alternative—especially because it is derived from plants. This fact makes it seem more "natural" than some artificial sweeteners. However, even natural foods may have some health risks if consumed in excess.

In 2008, the FDA approved some forms of purified stevia extracts and gave them "generally regarded as safe" (GRAS) status. These include:

• 95% minimum purity steviol glycosides

• Rebaudioside A (also known as Reb A)

• Stevioside

• Rebaudioside D (also known as Reb D)

In contrast, whole stevia leaf and crude stevia extracts are not GRAS. They also are not permitted for use in the U.S.

Health Benefits of Stevia

Stevia has been studied for more than 100 years, so there's a lot of scientific information available to demonstrate its potential health benefits. Here's what you need to know about the pros of using stevia.

May Have Anti-Cancer Properties

The FDA banned stevia in 1991 after some clinical studies linked it to cancer. In the 30 years since then, scientists have found that those early studies were incorrect. Interestingly, studies in the 2020s are now looking at stevia as an anti-cancer agent, and it is being tested as a possible medication to fight gastrointestinal cancer cells.

The bottom line is that stevia does not cause cancer and may help kill some types of cancer cells. Research in this area is ongoing, though.

May Be Safe for People With Type 2 Diabetes

Stevia is considered safe for people who have type 2 diabetes. In Brazil and Paraguay, where stevia was first grown, it is used as a traditional medicine to treat diabetes.

In clinical studies, stevia was found to have no detrimental effects on blood sugar levels or insulin levels. In fact, it can help stimulate insulin secretion from the pancreas, which helps lower blood sugar levels. A few studies have even found that stevia can reduce blood sugar by up to 35%.

Helps Lower Blood Pressure

Stevia is also safe for people with high blood pressure. Some healthcare providers even recommend stevia to prevent or treat hypertension. That's because stevia acts as a vasodilator, which means it opens (dilates) blood vessels to promote healthy blood flow.

If you have low blood pressure levels, talk to your healthcare provider before adding stevia to your diet. It could decrease your blood pressure levels even further.

Possible Concerns About Stevia

Despite its potential benefits, stevia still is not suitable for some people. Here are some potential downsides to using stevia as a sugar substitute.

May Impact Body Weight

All low-calorie sugar substitutes, including stevia, are promoted for weight management. However, the research on this topic is not clear-cut. Some studies show that using low-calorie sweeteners may actually increase weight, body mass index, and the risk of cardiometabolic disease.

As always, weight loss isn't a topic with a "magic bullet" answer. Simply switching from sugar to stevia is not going to be a miraculous solution for weight control.

May Cause Digestive Issues

Some people have reported adverse gastrointestinal effects from stevia, including bloating and nausea. These are individual experiences and will not happen to everyone who uses stevia products.

Notably, people usually report these symptoms when they use stevia in very large amounts. The safe daily intake level for stevia set by the World Health Organization is 4 milligrams per kilogram of body weight. In practical terms, that's about 10 stevia packets for someone who weighs 150 pounds.

May Harm the Gut Microbiome

Studies on how stevia affects the microflora in your gut have been mixed. One review looked at 14 past studies on stevia and gut microbiome health. Some of the studies showed beneficial effects, some showed no effects, and some showed harmful effects from stevia. It's too soon to say if stevia is helpful or harmful to the gut microbiome, and studies are ongoing.

May Cause Hormone Disruption

Steviol glycosides, the component that gives stevia a sweet taste, share a similar structure to steroids. There is some concern that this can impact steroid hormones, such as progesterone.

One study shows that the use of stevia can increase progesterone. That could be problematic, since high progesterone is linked to depression and weight gain. However, only one study exists on this topic, so more research is needed.

Not Safe During Pregnancy

To date, there is not enough research to determine the safety of taking stevia during pregnancy or while breastfeeding. Because it is unknown, it is best to err on the side of caution and avoid stevia when pregnant or breastfeeding.

Could Be an Allergen

Stevia is a plant in the Asteraceae and Compositae family, which also includes the common allergen ragweed. If you have a ragweed allergy, you may also react to stevia. Check with your healthcare provider to determine if it's safe for you to consume.

Should You Use Stevia?

As with any change to your diet, it's important to work with your healthcare team for personalized advice before deciding to switch to stevia. They can help you make informed decisions based on your individual health needs. Here are some other things to keep in mind if you decide to use stevia:

• Consider the source. Do not use whole stevia leaf and crude stevia extracts. Instead, look for products that contain steviol glycosides, steviosides, or Rebaudioside A or D.

• Start with small quantities. Use one packet or tablet to see if you enjoy the taste and to see if there are any side effects before using a larger quantity. Do not exceed 10 packets or tablets of stevia in a day.

• Mix it up. Instead of relying on one sweetener all of the time, choose a variety of sugar alternatives.

• Consider the other ingredients. Choose a product that is mixed with a bulking agent like dextrose instead of erythritol, which has recently been linked to an increased risk of heart disease. Long-term safety of erythritol is currently being studied, so it may be smart to avoid it as your main sweetener until more is known.

Bottom Line

Remember, stevia is just one ingredient and is not a magic bullet for health. It may help you mindfully reduce your sugar intake. But, be careful not to simply swap high-sugar foods for many other ultra-processed foods that contain stevia, such as candy and ice cream. Moderation of these foods—whether they are made with sugar or stevia—is a better idea.

Read the original article on Verywell Fitness.