Digestive difficulties are one of the most commonly suffered health problems today. It is thought that nearly 80 million Americans suffer from at least one form of digestive dysfunction on a weekly basis; 10 million of these people are hospitalized each year, while doctor visits attributed to digestive problems occurs nearly 50 million times each year.  All of these problems are thought to cost nearly 107 billion dollars, in both direct and indirect costs each year! It is interesting to note that two of the most popularly prescribed pharmaceutical medications in history are for treatment of digestive problems. This simple fact puts into perspective the widespread nature of digestive problems. Perhaps the best way to address this problem is the use of digestive enzymes. Digestive enzymes, simply put, provide the means for the body to assimilate foods and to incorporate their nutrients into the many different bodily systems in which they are required. When a substance (such as food) needs to be transformed into another form (individual nutrients), digestive enzymes are responsible for this process.
Unfortunately, as evidenced by the statistics above, many people are unable to properly digest their foods, leading to many different categorical signs and symptoms of problematic digestive processes. The dietary supplementation with digestive enzymes offers a simple and effective way to increase the efficiency of digestion in the body. Digestive enzymes, when added to the diet, will increase the release of the energy that is stored within the foods eaten. Foods that are left partially or improperly digested lead to gastrointestinal health problems both in the short and long term.
Digestive enzymes typically include the following types:
- Proteases: digestion of proteins
- Lipases: digestion of fats
- Amylases and Cellulases: digestion of carbohydrates
This is a broad grouping, as there may be up to hundreds of different enzymes that fit into each of the categories listed above.
Naturally occurring food sources of proteases, amylases, and lipases are quite rare. In the recent past, many of these digestive enzymes were derived from animal sources (pancreases of livestock animals). However this process has fallen out of favor and the majority of digestive enzymes are now manufactured using the fungus aspergillus. Scientists have learned to alter the chemical machinery of this plant to produce the aforementioned digestive enzymes needed to effectively dismantle proteins, fats, and carbohydrates. Aspergillus-derived enzymes are 100% vegetarian and have an extremely strong safety record; these enzymes contain no trace of aspergillus either. 
Otherwise, there are thousands of different types of enzymes found in plants and animals. Fresh, uncooked foods (vegetables and fruits) contain certain types (mainly cellulase) of enzymes in very small amounts. These enzymes are contained in the cells of the food and are released by chewing and the natural digestive process taking place within the body. While the presence of such enzymes is beneficial in these foods, their amounts are typically too small and therefore may have a negligible effect on the digestive process. Proponents of ‘raw food diets’ may, however, argue otherwise.
Digestive enzymes are used to assist the normal digestive process. More often than not, people have lower amounts of gastric acid than needed for proper digestion.  There are numerous indications for digestive enzymes, all of which center around improving the function of human digestion. Common signs and symptoms of improper digestion include nausea, gas, bloating, and heartburn. However, it is important to note that these may be symptoms of a more serious underlying problem. Treatment of digestive difficulties with enzymes should always accompany a full work up of symptoms by a medical practitioner.
Protease: Specific for breaking down proteins (most commonly from animal food sources), there are numerous types of protease. In fact, it is thought that the body produces up to 3,000 different types of protease in the digestive process. The body makes many different types of protease enzymes in order for protein digestion to occur along the entire pH spectrum in the gastrointestinal tract. Each one of these proteases works at a very specific pH range.
As the process of digestion unfolds, dietary protein (and for that matter, fats and carbohydrates) is continually digested at different pH levels; this is part of the reason why the body supplies so many different types of enzymes, ensuring complete and adequate digestion. Supplementation with a broad range of protease enzymes gives the body a variety of enzymatic powers to react against different dietary proteins.
For example, when we speak of animal proteins, although they are all considered ‘animal’, each one is very different in its protein makeup and therefore requires many different proteases to break it down. The more proteases, the broader the pH range, and the longer it works in the digestive tract.
Lipase: Lipase enzymes specifically target fats; typically accompanying animal protein sources (highlighting the consumer’s quest for ‘leaner’ cuts of beef, etc.). Lipase assists the digestive process by breaking apart fat molecules into their respective components - fatty acids and glycerol.  Lipase is found in a number of plant sources, dairy products, and animal tissues.  Similar to what was said about the many different types of protein necessitating a wide-ranging blend of protease enzymes, the same is true of those found in fat sources. A formula containing multiple forms of lipase, instead of only one, will allow the body to digest more fat over a wider pH range.
Amylase: This enzyme targets carbohydrates. Carbohydrates are primarily derived from plant sources. Examples of this include any vegetable source. Other than these unprocessed foods, many carbohydrates are available in a processed from; like bread, pasta, cookies, rice, cake, etc., are all sources of carbohydrate. Similar to the other main classes of enzymes, many different forms of amylase exist in order to breakdown the various types of cellular/carbohydrate sources. Amylase is secreted in large amounts in the saliva; this combined with mechanical breakdown (chewing) of foods is what initiates the digestive process. One can say that digestion truly does begin in the mouth. Amylase continues working throughout the entire gastrointestinal tract.
The dosages regarding digestive enzymes varies - different enzymes have varying systems of measurement. These systems typically address the enzymatic power of a particular enzyme that is contained in a given formula.
Administration of such enzymes should take place roughly ten minutes into a meal; this allows the body to get started with its digestive process (producing its own enzymes); supplementation then bolsters the body’s natural process.
Digestive Enzymes Deficiency
Deficiency of digestive enzymes cannot be directly tested for; a person’s symptoms will typically reveal an inefficient digestive process. There is one type of test that can indirectly measure digestive capacity. This test involves swallowing a small capsule that measures the acidity level (pH) in the stomach and intestines, then relays this information via radio transmitter. Combined with this information and specific clinical symptoms, one may be diagnosed with low levels of digestive capacity.
Digestive Enzymes Toxicity
Digestive enzymes themselves have a very low possibility of creating toxicity in any form. Commonly, the only problems encountered with digestive enzymes are instances in which too strong of an enzyme is taken; symptoms usually involve warmth and even a burning sensation in the stomach. There is a small chance that when taken together with other pharmaceutical drugs, enzymes may alter the way the drug affects the body. Otherwise, digestive enzymes are considered safe when taken as directed.
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