What is aloe vera?
The aloe vera plant (Aloe barbadensis) is the source of two very different herbal products: aloe gel and aloe juice (also called aloe latex). Although you may hear the terms juice and gel used interchangeably, it's important to know the difference. Aloe gel, the clear, jellylike stuff that oozes from a torn leaf, is renowned as a salve for burns and wounds and is also the key ingredient in many cosmetic products; it has also been used orally for ulcers, diabetes, and asthma, among other things.
In contrast, aloe juice (usually sold in dry form as a powder that can be reconstituted) is useless against burns and wounds but has long been used as a laxative. Some people have also used the juice for health problems ranging from seizures, colds, ulcers, and colitis to depression, glaucoma, arthritis, hemorrhoids, varicose veins, and multiple sclerosis.
Does aloe really work?
If you keep an aloe vera plant in your kitchen for this purpose, you probably already know how soothing the gel feels on a burn. You may have also noticed that it can ease the itching and inflammation that go along with minor wounds.
There is evidence that aloe vera gel can help to alleviate psoriasis. It may also be effective on burns, frostbite, and herpes simplex outbreaks, although more research is needed to confirm these findings. A 2008 study of burns found that although the aloe helped to reduce skin temperature, it did not aid in healing the burn. Very little study has been done on the use of aloe on actual human wounds, and the results of existing research are contradictory. While some studies have found that aloe can facilitate wound healing, more recent studies have found little benefit. And at least one study found that applying aloe gel to surgical wounds can actually delay healing. A small study in England in 2004 found aloe vera gel to be effective at improving symptoms of inflammatory bowel disease, but more research is needed in this area as well.
As for aloe juice, it seems to live up to its billing as an effective (although risky) laxative. According to the Complete German Commission E Monographs, a comprehensive source of information on herbs, aloe juice encourages bowel movements by triggering small contractions in the colon.
Is aloe safe?
Applying aloe gel to the skin appears to be safe even during pregnancy and lactation, although the maximum length of treatment hasn't been established. Aloe gel can sting a bit when first applied to a wound, but the unpleasantness passes in 20 to 30 minutes. According to the Natural Medicines Comprehensive Database, the gel is well-tolerated when taken orally.
Aloe vera juice requires much more caution and should not intentionally be ingested at all. In 2002, the U.S. Food and Drug Administration ruled that aloe laxatives in over-the-counter drug products are not safe and required that they be removed from the market or reformulated. In general, it's best to avoid any type of laxative unless a doctor recommends it, and you should not take any laxative that stimulates the colon for more than one or two weeks.
Be aware that aloe juice may interact in a hazardous way with diuretics, corticosteroids, laxatives, heart drugs known as cardiac glycosides, warfarin, and drugs taken to prevent arrhythmia, or irregular heartbeat; it may also reduce the potency of other prescription drugs.
In addition, long-term use of aloe juice can result in severe diarrhea, potassium loss, muscle weakness, weight loss, kidney inflammation, heart disturbances, and blood in the urine.
How should I shop for aloe gel?
If you're not getting your aloe directly from a freshly plucked leaf, it pays to be cautious. Some so-called aloe products contain very little of the plant material, and the aloe that is there might be a pale shadow of the fresh gel. Don't buy products that offer "aloe vera extract" (that's code for "extremely watered down") or "reconstituted extract" (that means "far from fresh"). Look for a product that lists "aloe gel" high in its list of ingredients.
What are the typical dosages?
Aloe gel is applied to the skin 3 to 5 times daily as needed.
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