The aloe vera plant has long, thick triangular leaves and is relatively easy to grow at home. The outer layer is the rind, the middle layer is a bitter yellow sap, and the center is a gel (which can be applied directly to the skin). The plant can also be peeled and juiced; oral supplements are also available.

This article discusses the health benefits of aloe vera and the scientific research behind it. It also discusses potential side effects and harms from aloe vera, who should not use aloe vera, and what to look for when choosing aloe products.

Uses of Aloe Vera

Aloe vera has been used to treat many conditions. As you review the science surrounding aloe vera, please remember that supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian, pharmacist, or healthcare provider. No supplement is intended to treat, cure, or prevent disease.

Skin Health

People have used aloe vera gel to treat many skin conditions, such as sunburn, thermal burns, and other common skin conditions.

A randomized controlled trial in humans suggested that topical aloe gel reduces markers of inflammation. Laboratory research supports that aloe vera also promotes the creation of new skin cells, protective cells (keratinocytes), and cells that help skin strength (fibroblasts). Additionally, laboratory research has suggested that components of aloe gel act as antioxidants and have antibacterial effects.

However, is there evidence that aloe can significantly impact your health? The available research is often conflicting. Studies of topical aloe vera’s effect on wound healing are inconsistent, with some studies showing delays. Although clinical trials specifically assessing aloe vera and thermal burns are supportive that applying aloe can improve recovery.

Even though aloe vera gel is commonly used for sunburn treatment, research on this topic is minimal. Of the few studies available, the majority support that aloe vera gel can increase the speed of recovery from sunburn. Research on pain relief with the topical use of aloe is also scarce, and results are inconsistent. More research on pain relief is needed before conclusions can be drawn.

While some laboratory and animal studies suggest aloe could benefit people living with psoriasis and eczema, high-quality human research is needed. A review article published in the American Journal of Clinical Dermatology found that there was not enough evidence to recommend using aloe vera to treat these conditions. No research on using aloe vera to treat rashes from allergenic plants such as poison oak and ivy is available.

Diabetes & Metabolism

Diabetes mellitus is a condition that results in changes in the body’s ability to control blood sugar levels. Type 2 diabetes is a common condition and has a major impact on the health of those living with the condition and is a focus area for new therapies. Research on the effect of aloe vera on diabetes is somewhat mixed and studies are often hard to compare due to the different forms of aloe vera used (such as aloe gel powder, aloe juice, or whole leaf extract).

Researchers created a summary of many studies (i.e., a systematic review) on type 2 diabetes. The researchers found “moderate-quality” evidence supporting the use of aloe vera to lower blood sugar levels in people with type 2 diabetes. Many unknowns remain, including which form of aloe vera supplement is most effective. It’s worth noting that aloe vera gel and gel-based products (i.e., aloe juice, typically made from the gel) were the most common forms used in the studies.

People living with type 2 diabetes often experience changes in cholesterol and triglycerides, referred to as dyslipidemia. An overview of systematic reviews assessed the effect of aloe vera on cholesterol and triglyceride levels. A significant difference in LDL (bad cholesterol) was not seen with aloe vera supplementation. However, a significant increase in HDL (good cholesterol) was noted. Additionally, a significant reduction in triglyceride levels was seen in the aloe vera group.

Gastrointestinal Health

Aloe vera’s effects on gastrointestinal (GI) health is another area of interest for researchers and those affected by GI conditions. Conditions such as irritable bowel syndrome, inflammatory bowel disease, and gastroesophageal reflux disease are common and disruptive to many people’s lives. These conditions are common and impact the quality of life. A closer look at aloe vera and whether it can affect these conditions is warranted.

Irritable Bowel Syndrome (IBS)

Researchers have studied aloe vera for its impact on IBS, a disorder of the gut-brain axis (previously called function GI disorders). Irritable bowel syndrome is diagnosed by the signs and symptoms of those with the condition when there isn’t another apparent cause. Signs and symptoms may include one or a combination of the following:

Abdominal pain Abdominal discomfort Constipation Diarrhea

The evidence that aloe vera can reduce IBS symptoms is weak. A review of studies looking at the impact of aloe vera (in gel form and decolorized extract) found that the few studies available in this area showed no real benefit. Ultimately higher-quality research in this area is needed to form any firm conclusions.

Inflammatory Bowel Disease (IBD)

Researchers have studied aloe vera for its effect on a set of conditions called inflammatory bowel disease. These more specific conditions are Crohn’s disease and ulcerative colitis. Crohn’s disease results in higher levels of inflammation and can impact any portion of the gastrointestinal tract. Ulcerative colitis primarily affects the large bowel (colon, rectum, and anus) but may also affect the last part of the small bowel, the ileum. Symptoms of inflammatory bowel disease are as follows:

Abdominal crampsPainRectal bleedingBloody diarrhea

Inflammatory bowel disease can result in severe complications, and additional options are needed to help manage the condition. However, is there evidence that aloe vera can positively impact people with this condition? Little research has been done in this area, and more research is needed.

One early study of 44 people with mild to moderate ulcerative colitis found that aloe vera gel, taken twice daily, had a “response” after four weeks to the treatment more often than those receiving a placebo. By a “response,” the authors meant that participants had improvement of their symptoms or remission of the condition. Unfortunately, this is just one small study, and additional research is needed to confirm these results.

Gastroesophageal Reflux Disease (GERD)

GERD is a condition where the movement of stomach contents results in unpleasant symptoms, such as burning (heartburn) or bloating. Those with GERD may experience injury to the lining of their esophagus, which can increase the risk for esophageal cancer, bleeding, and other complications.

Little research has been conducted on aloe vera’s impact on gastroesophageal reflux disease (GERD). A small randomized controlled trial including 79 participants compared the effects of aloe vera gel on GERD symptoms, compared with standard treatments. These standard treatments included ranitidine (an H2-receptor antagonist) and omeprazole (a proton pump inhibitor). Researchers ultimately found that the aloe vera gel significantly reduced all symptoms assessed (for example, heartburn, regurgitation, and belching) and had an effect similar to ranitidine and omeprazole. Though the current research may produce optimism, more, higher-quality studies need to confirm the results.

What Are the Side Effects of Aloe Vera?

Side effects of aloe vera are uncommon. The risk of side effects may vary based on the form of aloe vera and whether it is applied to the skin or taken orally.

For example, aloe vera gel appears to be associated with fewer adverse reactions than aloe vera whole leaf extract and aloe latex. The gel has been associated with skin discomfort, pain, and dermatitis in some individuals. Overall, adverse reactions with aloe vera gel appear uncommon and non-severe.

Common Side Effects

DiarrheaNauseaVomitingAbdominal pain

Severe Side Effects

Allergic reaction: When applied to the skin or consumed orally, aloe vera may cause dermatitis, hives, cramping, and diarrhea in those that also have allergies to other plants in the lily family (for example, onions, garlic, and tulips). Hepatitis (liver inflammation): Damage to the liver is more likely to occur when aloe or aloe latex supplements are taken in larger quantities. The exact amount and duration required to have an effect are unknown and likely vary from one person to the next. However, as little as 500 milligrams every two to three days has been associated with hepatitis. The average duration identified by a review of case studies was 60 weeks or about 15 months of supplementation. Data regarding doses of aloe vera latex that have negative side effects are even more limited. Kidney injury: The quantity and duration of aloe vera extract and latex that cause renal (kidney) damage are also limited. A published expert statement from a toxicologist that prolonged use of greater than 1 gram per day of aloe vera latex can result in acute renal failure is commonly quoted. However, the source and quality of this information are unknown. Possible cancer risk: There have long been concerns about an association between laxatives that contain anthraquinones (such as aloe vera) and colorectal cancer. A systematic review and meta-analysis was recently carried out on this topic. This means that researchers reviewed current studies on this topic and combined the data to let us best understand what the recent research says as a whole. The researchers found that the studies had limited quality and could not determine with certainty that there is an association between anthraquinone laxatives and colorectal cancer.

Precautions

The use of non-decolorized whole leaf aloe vera extract or latex may pose additional unique risks to specific populations:

In 2002, the Food and Drug Administration (FDA) required that aloe latex be removed from over-the-counter (OTC) laxative products due to a lack of available safety data. As a result, these products are now sold as nutritional supplements, which the FDA does not as closely regulate.

Pregnancy: Stimulant laxatives, such as aloe vera latex and non-decolorized whole leaf aloe vera extract, should be avoided in pregnancy. This is because there is concern that they may stimulate uterine contraction. This may increase the risk of miscarriage or preterm labor, though research here is very limited. Breastfeeding: Aloe vera latex and non-decolorized whole leaf aloe vera extract should also be avoided when breastfeeding. Little research is available here, but compounds from the aloe vera are transferred to breast milk. This could result in adverse effects, such as diarrhea, in your baby.

The aloe plant contains anthraquinones, which are thought to give aloe latex its laxative effect. However, in 2002, the Food and Drug Administration (FDA) required aloe latex be removed from over-the-counter (OTC) laxative products due to a lack of available safety data. As a result, these products are now sold as nutritional supplements, which the FDA does not as closely regulate.

How Much Aloe Vera Should I Take?

Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.

There are no standard doses of aloe vera in any form. The effects and risk of side effects can vary based on the type of aloe vera supplement, your age, weight, and health status.

Aloe vera gel-based products meant for the skin may be in concentrations as little as 0.5% to over 99%. There is no data to suggest that lower concentrations are less effective than higher concentrations. It may be best to begin with a lower concentration and monitor for improvement of symptoms as well as adverse effects. Adjustments can be made from there as needed in consultation with your healthcare provider. Stop using a supplement immediately if you notice any adverse effects.

Oral forms of aloe may come in capsules, powders, and juices. Supplement doses available vary significantly, and this is partly related to the type of aloe vera supplement as well. Please remember that aloe vera latex and non-decolorized whole leaf extract are associated with more adverse effects than aloe vera gel. You should discuss the use of all nutritional supplements with your healthcare provider, especially when using those with a higher risk of adverse reactions.

Aloe vera gel is relatively safe and doses of 300 milligrams (mg) taken twice daily appear to be associated with improvements in blood sugar. Doses of 500 milligrams taken twice daily appears to be associated with improvements in blood sugar and lipids (cholesterol and triglycerides).

What Happens if I Take Too Much Aloe Vera?

Aloe vera can be toxic if you take too much, especially for an extended period. Toxicity means that the aloe vera begins having negative effects on the body, which can even be life-threatening.

While animal studies have shown that aloe vera gel can have toxic effects, there is little evidence of this in humans. Aloe vera gel may have adverse effects when applied to the skin, such as discomfort, pain, and dermatitis. There is no evidence that aloe vera gel has toxic effects in humans when taken orally. However, nutritional supplements are loosely regulated in the United States, and the quality of supplements varies. If aloe vera latex is not correctly removed from an aloe vera gel supplement, the risk of toxicity will be greater. Stop using the product immediately and consult with your healthcare provider if symptoms are severe or persistent.

Aloe vera latex and non-decolorized whole leaf extract (which contains the latex) have a greater toxicity risk than aloe vera gel. Unfortunately, the amount and duration required to produce toxicity are unclear. However, as little as 500 milligrams per day of non-decolorized whole leaf extract has been associated with adverse effects. The average duration identified by a review of case studies was 60 weeks or about 15 months of supplementation.

It is unclear if a safe and effective amount of aloe vera latex exists. Experts have stated that high doses, such have 1 gram per day, can be fatal. Due to the uncertainty regarding the amount of non-decolorized whole leaf extract and latex required to cause toxicity, these products should be avoided unless recommended by your healthcare provider.

Interactions

Aloe vera may interact with certain medications. This means it may have the opposite effect of drugs you already take. Or it may ultimately result in a greater overall impact. This can lead to problems with side effects or the treatment of your existing health conditions.

Speaking with your healthcare provider before adding supplements or alternative medicine products is always a good idea. That’s especially true if you are taking:

Diabetes medications, including insulin: Aloe vera gel can reduce blood sugar. If you’re already taking medications that reduce blood sugar, your blood sugar levels could go too low. Laxatives: As aloe vera latex and non-decolorized whole leaf extract act as laxatives, taking this along with other laxatives could result in diarrhea. This may increase the risk of dehydration and electrolyte abnormalities. Diuretics (water pills) like Lasix (furosemide): The laxative effects of aloe vera latex and non-decolorized whole leaf extract can cause diarrhea and the loss of water and potassium in the stool. Furosemide and other loop diuretics result in the loss of potassium in the urine in addition to water. Diuretics and certain aloe vera products could increase the risk of dehydration and low potassium blood levels (if using a loop diuretic like furosemide). Heart rhythm medications like digoxin: Low blood potassium levels can increase the risk of toxic effects from digoxin. As aloe vera latex and non-decolorized whole leaf extract increase the risk of low potassium levels, they could also increase the risk of toxicity from digoxin. Anticoagulants (such as aspirin, warfarin, and enoxaparin): Research has shown that aloe vera can also act similar to anticoagulants (or blood thinners) and reduce blood’s ability to clot. Taking aloe vera with anticoagulant medications could therefore increase the risk for bleeding.

It is essential to carefully read a supplement’s ingredient list and nutrition facts panel to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications.

How to Store Aloe Vera

Store aloe vera in a cool, dry place. Keep it away from direct sunlight. Discard the supplement as recommended by the manufacturer on the packaging.

Similar Supplements

There are other supplements with effects that overlap with aloe vera. Several are listed below.

Aloe arborescens Aloe ferox Cascara Sagrada Magnesium Rhubarb Tumeric Senna alexandrina

Other aloes, senna, rhubarb, and cascara sagrada are all anthraquinone laxatives, similar to aloe vera. Magnesium may have laxative effects. Turmeric (Curcuma longa) and its biologically active component, curcumin, have been associated with other benefits similar to aloe vera. For example, curcumin has been associated with improvements in blood sugar and possibly skin health.

Sources of Aloe Vera & What to Look For

Pure aloe vera gel contains healing amino acids, fibers, lipids, sterols, and vitamins. The gel from the plant is safe to eat, but you should not consume store-bought aloe vera gel.

Aloe vera products include topical gels, juice, and oral capsules.

These are approved for cosmetic or dietary supplement use, but are not intended to treat any medical condition. They are also not tested for quality or safety.

Since few aloe vera supplements are certified by the U.S. Pharmacopeia (USP) or similar certifying bodies, stick with well-known brands with an established market presence.

Summary

People have used Aloe vera for medicinal purposes for centuries. It remains an alternative medicine option today, but the research supporting its health benefits is limited.

Its most common use is its application to the skin to assist in burn healing. There is weak evidence to support its effectiveness in supporting recovery from ultraviolet radiation and thermal burns. Additionally, a limited amount of evidence supports aloe vera’s ability to improve blood sugar and lipids. Additionally, more research is needed regarding the effect of aloe vera on gastrointestinal conditions.

Finally, aloe vera latex, also found in non-decolorized whole leaf extract, has laxative properties. However, latex is also associated with more adverse effects than aloe vera gel. Due to this, you mustn’t use this product before talking with your healthcare provider. To be safe, you should always discuss with your healthcare provider before beginning a new nutritional supplement.