Silvie+Maryl – Holistic Living, Plant-Based Diet, Recipes, Love & Relationship, Healthy LifestyleTips

You see something. You think it’s yummy (or you say, “this is healthy for me!” Thumbs up.)  You put it in your mouth. It disappears. Now what happens? Let’s follow some food down the rabbit hole.

The digestive system starts in the mouth, the place where ingestion (you putting your food in your mouth for it to enter your body) takes place.  The first thing that happens is the secretion of saliva.  Saliva is actually pretty amazing: It lines and protects the inside of the mouth from superficial damage, makes the food easier to swallow, and has chemicals that help neutralize acid and prevent tooth decay, as well as antibacterial agents that get rid of many of the bad guys that come in with food. Probably the most known action of saliva is that it contains amylase, an enzyme that digests carbohydrates.  So, of all the macronutrients (carbs, proteins and fats) the carbs (sugars and starches) are what gets digested first chemically, starting in your mouth. Physical digestion (the actual breaking down of foods into physically smaller pieces by a force exerted on them) is what your teeth are for. Chewing is a crucial part of digestion, so spend some time there and chew your food well, because food has to be in very tiny molecules before it can be used by your body. After your food has been partially chemically digested and you have chewed and physically broken it down, your tongue helps shape it into a bolus, and then pushes this bolus (ball) down the pharynx.

From the pharynx, the food goes to through the esophagus and into the stomach (this takes about 5-10 seconds), where digestion continues for 2-6 hours, depending on what you ate. The stomach is a stretchy sucker, and it can expand to hold about 2 liters of food and drink, more than enough space for a full meal. The stomach is not the main place where food gets digested, contrary to popular belief, but it does play an important part. Here is where gastric juice is secreted. The muscles that line the stomach churn the gastric juices and mix them with the bolus, and your food is broken down further (if you’re starving and you hear “hunger pangs”, that’s your stomach churning!).This gastric juice is an interesting guy. It is acidic enough to dissolve iron nails (pH 2). With this industrial strength, it further takes apart our food chemically, kills bacteria, and introduces pepsin in the mix, an enzyme used to break down proteins.

How does the stomach not digest itself? It has a mucus lining that protects its insides from all of these harsh chemicals. Also, pepsin doesn’t become active and able to break down stuff until it gets to the lumen of the digestive tract. As the churning continues and the chemicals (acid, enzymes, food) mix, what was once your meal turns into a nice broth called acid chyme (chyme is what you feel when you get heart burn). There is an opening from the stomach to the small intestine and it is controlled by a regulator called the pyloric sphincter. Chyme passes from the stomach to the small intestine one quirt at a time (which is why it takes 2-6 hours for the stomach to empty – not to digest your food as digestion mostly takes place in the small intestine).

Now we’re getting to the place where the action happens: the small intestine. This guy is six meters long and all convoluted. The first 25 cm of it is called the duodenum and it is in this section of the small intestine where acid chyme mixes with digestive juices from the real heroes of digestion: the pancreas, the liver, gallbladder and gland cells of the intestinal wall itself. While the environment in the stomach is ultra acidic, the environ in the duodenum, thanks to the chemicals provided by these guys, is much more alkaline. Acid-alkalinity balance is crucial for digestion and absorption because this relationship dictates the behavior of chemical compounds in our body.  If an environment is too acidic, chemicals will travel to it to make it alkaline, and vice versa.  The thing is, the Western diet, based on animal protein and bad fats, is way too acid-forming for our bodies, and usually throws off some mechanism in our body.  Your body has the ability to neutralize too much acidity, but at the cost of alkaline nutrients like calcium (which is why it is said that dairy products, acid-causing, tend to leech calcium from our bones).  Anyway, acids and bases are a major subject of concern for us, but a topic for another post.

In the duodenum, carbs that started digesting in the mouth, proteins that began to be digested in the lumen of the stomach, and fats (which, until this point, where not digested at all…you see why fats cause trouble – they are the last thing to be digested) all get fully digested, all thanks to enzymes provided by the pancreas and bile from the liver and gallbladder. The macronutrients (carbs, proteins and fats) are now completely broken down into molecules that can be absorbed as they travel through the rest of the small intestine.  This is a crucial process. It does you no good to eat something that will not be absorbed by your body. The thing is, if we eat mostly processed foods or animal-based foods that throw off the pH balance of our body and are difficult to digest, then absorption suffers. If you eat stuff that your body can’t fully break down, then that food won’t get absorbed.  If that food doesn’t get absorbed, that means the nutrients that were in that food, will not be absorbed. And if you don’t absorb nutrients from a food, then you might as well have not eaten at all because THE POINT OF EATING IS TO ABSORB NUTRIENTS. You survive based on the various nutrients that your blood receives when you eat.  But if the nutrients cannot be digested, cannot be absorbed and cannot get to the blood, seriously: no point in eating.  Which is why it is really important to know how the digestive system works and what foods are easier to digest and better absorbed than others. And you can be sure that organic whole fruits, vegetables, nuts, seeds and grain are the easiest foods to digest and the most nutrient-packed ones, so you will absorb plenty of nutrition from them. These foods, because they are easier to digest, also save your body energy: digestion and absorption are processes that require energy, and it can take anywhere from (depending on how hard the food is to digest) 3%-30% of the chemical energy of the food you ate to actually process it, which either leaves 97% or just 70% energy for you to use.  Again, it’s up to you – you can either have an efficient system or a wasteful one.

Let’s continue. As the nutrients pass from the duodenum on through the rest of the small intestine, absorption continues and nutrients like vitamins, minerals, amino acids, sugars and more pass to either the lymphatic system, or to the liver, which processes these nutrients further and then sends them out as part of the blood through to the rest of the body, to perform functions like cell and tissue repairing and more.  Foods that are not absorbed will continue through the small intestine and end up in the large intestine, to be disposed of. One of the main functions of the large intestine is to absorb excess water from the digested food and other chemicals secreted during digestion. As this happens, the wastes of the digestive process (cellulose from vegetables, which helps move food along the intestine and out, bacteria that naturally live in the intestines and help this process, and other undigested stuff) become more solid, and we get rid of it when we go to the bathroom.

The entire process can take up to from 24-36 hours, from ingestion to excretion (and since we eat every day, excretion should take place AT LEAST once a day. If you’re not evacuating your bowels at least once a day, you’re not at your optimal health). Again, this all depend on the quality of food you eat, because this will dictate how quickly, fully and efficiently your food will be digested, absorbed and eliminated. Make the right choices of what you ingest and be sure to enjoy your meal, as things like stress can interrupt digestion. And take control of your digestive health by making informed food decisions.

It is said that the stomach is the “second brain” because if it empty, or not working right, it will not let you think straight. Ever tried to do something while you were starving?  Hopefully, this explanation has helped you see food and eating in a different light.  Here’s to your healthy and conscious eating!