Aloe vera, a botanical most consumers would say they know very well, is actually quite complicated. For starters, aloe" can refer to more than 400 species. Some, especially vera, offer a slew of health benefits, while others are related to cancer and other ill effects. Because of its health properties and low toxicity levels, aloe vera, aka aloe vera (L.) Burm. f., Aloe barbadensis, barbadensis (Mill.) or Miller, is the most commonly used aloe in consumer products.

Product manufacturers are therefore most likely to seek aloe vera for their beverages, lotions, tissues, etc., but its important they use the correct part of the aloe vera plant, as the components can offer varying effects; a consumer would become quite unhappy if he felt laxative effects instead of the antioxidant result he was expecting. The bitter, yellow-brownish, sap-like material found in between the inner leaf and the rind is known as aloe latex and is used primarily in crude drugs. Aloe latex contains anthraquinones, which cause a laxative effect in humans. The anthraquinone aloin is particularly known for its strong laxative properties.

To get to the inner leaf juice (aka aloe gel) without the latex and thus without the laxative effect, the plant is stripped of the outer rind either by hand or by machine (known as filleting," because the inner leaf without its outer plant shell looks like a fish), and the latex is rinsed away. The remaining material is then ground or crushed into juice. The fibrous pulp is usually discarded. This process leads to aloe that is decolorized" because removing the yellow latex leaves the juice clear.

Whole-leaf aloe is obtained by grinding the entire aloe leaf, then removing the rind material (usually using an enzyme treatment such as cellulose) and aloe latex via filtration (charcoal is a popular filtration form). A good filtration process removes the aloe latex down to 10 ppm or less in orally administered finished products and 50 ppm or less in cosmetic applications.

As ubiquitous as aloe vera products are, many confuse and combine the properties of the different species of aloe and components of aloe vera. It doesnt help that most pharmacopeias refer to aloe latex simply as aloe" or aloe juice."

Next: Government Study Finds Toxic Effect

Government Study Finds Toxic Effect

This confusion has led to one of the most-pressing issues in the aloe industry: a study conducted by the National Toxicology Program (NTP), an interagency program with the objective of evaluating substances of possible public health concern, in collaboration with FDAs National Center for Toxicology Research. The two-year study reported aloe was linked to carcinogenic activity in male and female rats, based on tumors of the large intestines. But whats important here is this study was not conducted on the type of aloe found in the natural products market.

The study, which has only been released in draft form, used a non-decolorized, whole-leaf extract of Aloe babadensis Miller that did not undergo charcoal filtration during processing; in other words, it was filled with latex and aloin. In a consumer information pamphlet, NTP said it used this aloe form because it wanted to test a preparation that included all components that may be in the products on the market.

The NTP studies consisted of a 14-day study in mice, a 13-week study in rats, a 13-week study in mice, a two-year study in rats and a two-year study in mice. In each study, the lab animals were administered the aloe preparation in various concentrations (1 percent, 2 percent or 3 percent wt/wt) or placebo. The two-year study in rats was the most damaging because it showed clear evidence" of carcinogenic activity based upon increased incidence of adenomas and carcinomas of the large intestine. Data from the other studies revealed exposure resulted in increased incidences of non-neoplastic lesions of the large intestine in male and female rats, the large intestine in both rats and mice, the small intestine of rats, the stomach in rats and mice, the mesenteric lymph nodes in rats and mice, and the noses of mice.

In its consumer pamphlet, NTP reported it suspects the aloin content caused the tumors, but it said it does not know for sure. NTP said the aloe rat studies give cause for at least three serious concerns: the aloe types currently on the market, the aloin levels in these products, and the patterns of human exposure. The agency said it hopes to do more studies.

FDA is after what caused damage to the rats," noted Devon Powell, executive director of the International Aloe Science Council (IASC). I'm not a scientist, but I think it's because the aloe wasn't filtered. Thinking logically, if you feed a rat aloe that's laced with aloe latex for two years, you are going to put them in a diarrhea state for two years. If you had diarrhea for your lifetime, I'm pretty sure you'd have some problems."

Powell noted the NTP draft report, which he expects will be finalized at some point, did not adversely affect the market. We thought it would; we were definitely afraid that it would," he said. When you say something like 'carcinogenic,' that causes people's ears to prick up."

It may just be the intervening work of the IASC that helped to keep the reports from causing the damage they could have. According to Powell, NTP was originally calling the preparation used in the studies whole-leaf extract of aloe vera," but thats not what they tested. They actually tested the non-decolorized form, which means they did not filter it," Powell said. "Our industry filters it."

To help NTP and FDA better differentiate between the preparations used in the study versus those that are on the market, the IASC met with FDA officials on May 10, 2011, and provided them with analytical results of a NTP study sample obtained by the council. The analytical results of the study material showed it contain 10,000 ppm to 13,000 ppm of aloin, which is 1,000 to 1,300 times the less than 10 ppm limit established by the IASC in 2009.

IASC said at that meeting, FDA officials informed IASC participants that the agency would be a co-principal investigator on a new 13-week study on aloe vera as a follow up to the NTP study.

Players in the aloe market dont seem to be too concerned with the NTP studys effect on the industry. I do not expect the study to adversely affect the aloe market," said Santiago Rodriguez, Ph.D., CEO, Lorand Laboratories LLC. People have been using aloe vera for millennia, and so it is pretty evident in the people's minds that the product is safe."

Some even praise the study. The NTP study is welcome as with any study done on aloe vera," said Patrick Anderson, western regional sales manager, Terry Labs. We do not expect any unusual outcomes. This type of study will only strengthen the safety and efficacy of aloe vera in the marketplace. The original NTP study focused on how the majority of processors within the aloe vera industry do not process aloe. With the new NTP study, we can now see true results because we have been asked to participate in how aloe is truly processed. Again, we expect great outcomes."

Bill Pine, vice president, Improve USA Inc., has a wait-and-see attitude. The first study was conducted on an ingredient that is not normally available in the consumer market, so we can only respond by assuring the consumer that aloe has been consumed for approximately 50 plus years with little or no indications of contraindications," he said.

Next: Round up of Aloe Studies

Round up of Aloe Studies

Next: Necessary Standards

Necessary Standards

One way manufacturers can assure consumers is by testing products for aloin content. The IASC holds the position that aloe vera products meant for consumption should have an aloin content of 10 ppm or less, and companies should be able to provide that information to consumers upon request. Powell said the IASC came up with that number based on adverse event report (AER) data.

But consumers take aloe not only because it doesnt cause cancer, but because it can offer health benefits. However, these benefits can only be realized if products actually contain enough active ingredients. Rodriguez said the lack of consistent quality among both raw material producers and finished product makers is the biggest issue facing the aloe industry. Many people use aloe as a label claim, but dont really put a significant amount of it or use a good enough quality to produce an effect," he said. This backfires in the long run, since consumers become disappointed after using the products and not getting the expected effects."

Shaun Bozorg, eastern regional sales manager, Terry Labs, said some manufacturers can go even further than not containing enough active aloe; he said the greatest concern in the industry is the issue of adulteration. "Many so-called aloe products are adulterated by maltodextrin or other cheap fillers," he said. "The biggest issue is making sure aloe products are undiluted, unadulterated and of high quality."

Powell noted IASC has also seen maltodextrin as a common adulterant, so it tests its member companies for purity. It's important for any ingredient to have a framework of what's sold and what's not sold," he said.

To that end, the IASC established a certification program in the 1980s so aloe growers, processors and manufacturers could show their products contain an efficacious amount of aloe vera. The IASC program verifies products contain a string of sugars called acemannan, or beta 1-4 acetylated glucomanan, among other components. Acemannan is the major carbohydrate fraction obtained from the gel of the aloe vera leaf. It has been claimed to have several important therapeutic properties, including acceleration of wound healing, immune stimulation, anti-cancer and anti-viral effects (Immunopharmacology. 1996 Nov;35(2):119-28). Acemannan is naturally occurring in the plant and is measured by IASC using a nuclear magnetic resonance (NMR) method. The certification also requires an on-site audit for GMPs (good manufacturing practices).

"This seal of certification provides the consumer confidence that the product they are purchasing contains pure, quality aloe ingredients in conformance with the label," Pine said, adding, "Consumers should look for the seal."

But aloe vera is more than just acemannan, and depending on what other components are found in products, safety can be an issue. If the industry had a standard, Powell argued, FDA and NTP wouldn't question the safety of products on the market. Therefore, the IASC is also developing an aloe vera monograph it hopes to have published in the early part of 2012. "Standardization is a huge issue for this industry," Powell said. "It becomes difficult when something like the NTP study comes up because FDA wants to know what is in this stuff." The initial monograph will focus on standards and compliance, but the council hopes to add a therapeutic compendium in the near future.

Next: Meticulous Manufacturing

Meticulous Manufacturing

Obtaining a third-party certification and following a monograph can help differentiate a quality product from an inferior one, but manufacturing practices may play an even bigger role.

Pine said Improve USA's quality control starts at the field as the company owns and manages almost 2,000 acres of aloe. "Improve employs agronomists to monitor the aloe and recommend improvements in the fields, we maintain harvesting crews that work only for us and know the quality we require, and all aloe harvested is processed in 12 hours or less," he said.

According to Anderson, "Aloe has two enemies: heat and time." He said when heat is applied to aloe vera, the long-chain polysaccharides (aka the active ingredients) start to breakdown into smaller chains. "We process our aloe with low temperatures, which keeps the long-chain polysaccharides intact." Further, he noted Terry Labs uses reverse osmosis during the processing phase, which allows for no heat during the concentrating of aloe. "By not using heat to concentrate, we preserve the long-chain polysaccharides," he said.

 Taking too long to process the aloe can lead to degradation, Anderson continued. "We process our aloe immediately, so there is no degradation taking place with the raw plants." He said Terry Labs processes the aloe within a two-hour period.

For Rodriguez, the key to creating a stellar aloe product is a deep understanding of the chemistry and bioactivity of acemannan. "The primary concerns are in terms of the potential damage the processing can do to the acemannan chemically and to the biological activity of it as well. There are many aloe products in the market with very little or no acemannan at all as a consequence of a poorly designed process." He said Lorand Labs' flagship product BiAloe was conceived to deliver a large amount of bioavailable acemannan. "These considerations are very important, as we do no good if we have a large amount of acemannan, but it turns out the form of this acemannan is not bioavailable due to structure features related to processing among other factors."

An aloe product without enough acemannan would be a shame, but a product with too much aloin could be deadly, which is why manufacturers need to be on top of their aloe game. They need to test raw materials and finished goods, and have their marketing teams ready to discuss how their products differ from the one in the FDA/NTP study, should consumers ask. Seeking resources such as the IASC can help, but it's the onus of each company to make sure its aloe contains enough of the good, not too much of the bad, and the manufacturing processes to create consistent products.

References listed on the next page.

References

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