Do you occasionally have bloating, constipation, foul smelling gas, abdominal distension or heart burn? Are your hands or feet numb or tingling? Do you have an irregular heartbeat? If so, you may be suffering from alack of digestive enzymes.Whatever you ingest through your mouth will be digested and absorbed into your body, that?s self-evident.
It?s why so many people are leaning towards minerals and supplements as well as high-quality foods – because these beneficial ingredients will be digested, absorbed and utilized by the body. This is to assume that their digestive system is working properly, but that may not be the case. As we age, our ability to digest declines so that by the age of 75, our ability to digest decreases significantly.  But does it really matter?
Enzymes control almost everything in our body:
Digestion and absorption of nutrients.
Production of energy.
The repair of injuries in our body, healing wounds and repairing DNA. This basic mechanism protects us from cancer, and if unhealthy — you may be at increased risk.
Fighting infection by attacking bad microbes and dissolving their cell walls.
Regulating your energy production, fat-accumulation and breakdown.
Stopping the blood flow because of an injury, after a paper-cut for example
Thought processes and the ability to make logical conclusions.
Emotions; such as love or hatred.
Having sex.
Neutralizing poisons or toxic waste.
Enzymes essentially work like the oil in the engine of a car: without oil; the car stops. As you can see, enzymes regulate everything in your body; without them -you can?t function properly. Because of this, scientists have arrived at the conclusion that the effect known as ?aging? is in fact due to the loss of essential enzymes. The logic behind this is simple: with age we lose the ability to produce enzymes, which leads to an inability to absorb nutrients. Without these nutrients, our bodies are prevented from healing properly, producing enough energy, and fighting infections and cancer. The major enzyme types (5):
Metabolic enzymes, which are responsible for energy production, detoxification, etc. They are internal cells.  Example: coenzyme Q10.
Food enzymes, which assist our digestive enzymes in breaking down foods. Because enzymes are very delicate, they can?t tolerate the high temperatures associated with cooking. Therefore, these food enzymes are only found in raw foods.
Digestive enzymes, which help in digesting our food. They break down the foods we eat to make it easier for us to absorb and utilize.  With the lack of digestive enzymes in the stomach, you won?t be getting nutrients.
Digestive enzymes are divided in 3 groups:
Proteases ? breaks down proteins.
Lipases — digests fats.
Carbohydratases — responsible for digesting sugars.
  Digestive enzymes start working in our mouth: saliva has the enzyme ?amylase? – for sugar digestion.  That?s why chewing crackers leads to a sweet taste in the mouth. Saliva also contains ?Haptocorrin?, which is necessary for Vitamin B12 absorption. In the stomach, we have ?pepsin? for proteins, as well as hydrochloric acid. This has some pivotal roles in digestion: it activates other enzymes, makes essential nutrients ,minerals (like iron and magnesium) soluble (and therefore available for absorption), and it denatures proteins and kills bad bacteria.
Another important agent is called the ?Intrinsic Factor?, which is responsible for vitamin B12 absorption. In the small intestine, digestion reaches its peak.  The pancreas provides the small intestine with an abundance of multiple enzymes, which complete the digestive tasks that started in our mouth and stomach. These enzymes are: Trypsin and Chymotrypsin for proteins, Pancreatic Lipase for fats, Pancreatic Amylase for sugars, Cholesterol elastase, phospholipase, nucleases, etc.  
Digestion ends in the large intestine, which serves as a reservoir for feces before they are eliminated. Because digestion and absorption are the only natural ways to get nutrients, we cannot thrive if the system isn?t healthy. This is why digestive enzymes are used not only for problems of the digestive system, but also diseases that are unrelated to the digestive system, like cancer. The proposed mechanism of how enzymes fight cancer are:
They support our immune system, which already fights cancer.
They may break down the cancer cells? protective coverage which helps them escape our immune system?s recognition; enzymes make cancer cells vulnerable to an attack by our immune system. Unfortunately, as we age we lose the ability to produce the amount of enzymes necessary to benefit us in this way.  A western diet, as well as pharmaceuticals can do the same by depriving us from food enzymes (western diet), by shutting down the natural path of enzyme activation and production (such prescription drugs like Nexium, Prevacid, Omeprasol, Pepcid, etc.). This starts the vicious cycle of the end of life. Can this vicious cycle be broken — at least partially?
First; we may need to get enough hydrochloric acid in our stomach (it starts the main digestive process, together with ?enterokinase? produced by cells of the ?duodenum?).  Without hydrochloric acid, there won?t be any enzyme activation.  But some people have a high acid secretion; therefore acid production should be checked before considering digestive enzyme supplements. The same can be applied to the production of digestive enzymes — it should be checked and replenished if necessary, with prescription medications. But this is not the only choice left: we also have food enzymes which aid in digestion. Because the enzymes are very delicate, the foods containing them hould be consumed raw. The same can be applied to vitamins:
Want to get everything out of your foods? Eat it raw, provided that it is safe. Foods rich in digestive enzymes: Papaya, which contains the enzyme ?Papain? is very well known as a fruit filled with digestive enzymes.  In South America, they have being using it for thousands of years for cooking foods. Pineapple is rich in the natural digestive enzyme ?Bromelain?. It is used for many years as a meat tenderizer because of its digestive enzymatic properties. Cantaloupe, mango, avocado and bananas are also believed to have digestive enzymes.
How to boost your digestion with enzymes, naturally:
 Stick to raw food, provided it’s safe
 Incorporate enzyme-rich foods in your diet, such as papaya and pineapple.
 If possible, avoid drugs that reduce your stomach acids like Nexium, Prevacid, etc. Of course if you have to take them ? do so. Talk to your doctor about any health care decisions; do not stop taking these drugs unless approved by your doctor.
 Decrease your calorie intake to an optimal level, to minimize the amount of enzymes needed.
Good luck!  
References: 1.  Rafsky HA, Weingarten M. A study of the gastric secretory response in the aged. Gastroenterology 1947;May:348-352. 2.  Davies D, James TG. An investigation into the gastric secretion of a hundred normal persons over the age of sixty. Br J Med 1930;i:1-14. 3.  Baron JH. Studies of basal and peak acid output with an augmented histamine test. Gut 1963;4:136-144 4.  http://www.naturalhealthschool.com/6_5.html 5.  http://www.typesofenzymes.org/ 6.  http://en.wikipedia.org/wiki/Digestive_enzymes 7.  http://en.wikipedia.org/wiki/Bromelain 8.  http://www.ncbi.nlm.nih.gov/pubmed/10368805