Happens to What You Eat?

“I’M HUNGRY!” When your body makes this urgent demand, few put up much resistance to it.

But did you ever wonder what happens to what you eat? (Besides depositing itself on the waistline and discharged into the sewer). But what happens in between and why it happens is for the most part a real mystery—even to scientists. Let us, nevertheless, take a close look at current theories as to how the human machine is “fueled.”

Why You Get Hungry

The expression “you are what you eat” is overworked but nonetheless quite true. Your body cells are almost entirely composed of molecules extracted from foods and liquids you have consumed. Constantly your body is fueling, making, repairing or destroying these cells. So eating has a greater purpose than filling one’s stomach. It provides fuel and material for your body’s nonstop construction program. Our body is beautifully designed with a built-in alarm that lets us know when our bodies need more food. 

We feel hungry when our body needs more energy (in the form of glucose) or nutrients. … This causes particular groups of neurons in the hypothalamus to produce proteins, which make you feel hungry (NPY and AGRP). Many researchers believe that a part of the brain called the hypothalamus—not the stomach—plays a large part in igniting the desire to eat. True, a person with an empty stomach can suffer sharp stomach contractions. But is worth saying that most of us have never experienced this. Often one’s eating is prompted by habit or by psychological factors. Why, just the sight or smell of food can initiate hunger! In addition, though, the brain seems to monitor the body’s level of glucose in the blood, and a drop in this level can make you feel hungry.

Some even think that the brain has a predetermined “set-point” controlling how much body fat you have. Chemical “messengers” may inform the brain when fat levels are too low for the brain’s liking. As a result, you feel hungry. Fortunately, the brain also informs you when you have eaten enough. But if this system malfunctions (as it seems to do in some people), one may eat long past the point of satiation. This may be one of the many causes of obesity.

The Journey From Mouth to Stomach

Meat and vegetables supply vital nutrients, such as proteins, fats and starches. The problem is, however, that your body only assimilates small food molecules, whereas protein, fat and starch molecules are quite large. Digestion, therefore, chops these long chemical chains down to size. From the moment you see, smell or even think about a tasty food item, your body prepares itself for digestion. Imagine, for example, that you have before your eyes a piece of juicy, boneless breast of chicken, nestled between two fresh slices of whole-wheat bread. Just the sight of it starts your mouth watering, doesn’t it? Secretly, your stomach starts secreting digestive fluids. Now take a healthy bite of this luscious treat and your body’s digestive system swings into full gear. Your mouth warms (or cools) the food to the right temperature. Chewing not only lets you savor the food but also grinds it to an easily swallowed pulp. Salivary glands help by pumping out saliva to moisten and soften the food. Enzymes in the saliva go to work on the bread, transforming starches into simple sugars.

From Mouth to Stomach

Now take a healthy bite of this luscious treat and your body’s digestive system swings into full gear. Your mouth warms (or cools) the food to the right temperature. Chewing not only lets you savor the food but also grinds it to an easily swallowed pulp. Salivary glands help by pumping out saliva to moisten and soften the food. Enzymes in the saliva go to work on the bread, transforming starches into simple sugars.

From the mouth, your meal must now journey to its next stop—the stomach. There the chicken can be digested. Take a swallow. A reflex action closes your windpipe so that the food slides into the gullet, or esophagus. Its stay there is quite brief, however. Within a few seconds, muscle contractions help move it down toward the stomach. “The contractions are so strong,” says one writer, “that food would be forced down even if the eater were standing on his or her head.” A one-way valve called the cardiac, or lower esophageal, sphincter allows the food to pass into the stomach but prevents gastric juices from flowing back into the esophagus.

Anyone who has ever had the unpleasant experience of vomiting knows that the stomach is nothing less than a vat of acid. So for several hours the food churns in hydrochloric acid and enzymes. There your chicken is blended, sterilized and broken down into protein molecules called poly peptides.

Unfortunately, some people have a deficiency of hydrochloric acid and stomach enzymes. As a consequence, their digestion is seriously impaired. They may stuff themselves on nutritious food but suffer malnutrition nonetheless. On the other hand, some have an excess of stomach acids and suffer the familiar heartburn or even develop ulcers. Several hours in the stomach and the food is now a liquid mass called chyme. This liquid is gradually squirted into the duodenum, the first part of the small intestine. There the digestive process continues.

The role of the liver

The liver comes to the aid of enzymes present in the intestine by producing bile—a yellowish alkaline fluid. Your body produces about 17 to 27 fluid ounces (500 to 800 ml) of this salty fluid daily and stores it in the gallbladder. When needed, this organ secretes just enough bile to do its job of emulsifying fatty globules. This job accomplished, the enzymes are free to perform their chemical wonders. What’s left of your sandwich is transformed into microscopic particles! But how do these particles become a part of your body?

By absorption. You see, it takes the digested food some four hours to pass from the small intestine to the next step of its journey: the large intestine. In the meantime, it encounters millions of tiny, finger like projections called villi that line the walls of the small intestine. Through these villi, food is absorbed—either into the lymph (lymphatic) system or into the blood system. The blood system carries away the digested food material to that remarkable “factory,” the liver. There molecules are broken down yet further. Now when your body cells need repair, the liver uses these raw materials to manufacture or synthesize “spare parts”—amino acids and proteins. Too, it can store and later send out glucose to fuel your cells. The liver is also a warehouse. When further cell repair is needed, the body sends out a signal and the liver supplies some needed repair materials on demand.

What, though, of the food that wasn’t absorbed? Water eventually goes to the kidneys for elimination via the urinary bladder. Solid waste passes into the large intestine, or colon, for elimination through the rectum. Since the colon is at its most efficient when it is relatively full (and there is evidence of further health benefits), many doctors recommend a diet high in fiber, that is, indigestible materials such as bran, to aid in regular elimination.

Conclusion

What happens when we eat is amazing. We should take of our body by watching what we eat. Good nutrition is an important part of leading a healthy lifestyle. Combined with physical activity, your diet can help you to reach and maintain a healthy weight, reduce your risk of chronic diseases (like heart disease and cancer), and promote your overall health.

When you practice good nutrition, you’re consuming natural and healthy foods that can help your body. This includes improving your immune system. According to a 2011 study presented at the 5th International Immunonutrition Workshop in Puerto Valletta, Mexico, researchers showed how obesity can weaken someone’s immune system, thereby increasing the chances of getting sick from infections.

So what do you think about this topic? leave us a comment below.

Thanks for reading.

Eunice

16 Comments

  1. Amazing detailed information. I wonder what the problem is with my intestines; or is there even is any. I didn’t know there were 4 hours to pass before the food got digested. I have a digestive problem; have had it my whole life. I wonder what it causes it though. I am positive its not the food I eat. 

    • Thank you Linda for reading. Maybe is will be worth checking it out, or have you done that already? Sometimes it may not be food that cause it.

  2. Thank you for this educational and interesting post.
    I can’t leave without leaving you a word!

    In fact, in my school background, I really enjoyed science, and it was a real pleasure for me to devour your article!
    There are a lot of new things that I learned through your post that I didn’t get a chance to know while I was still on the benches.

    I agree with you: good nutrition is good for our health, but combined with physical exercise can help us avoid many chronic diseases.
    Looking forward to your next article!

    • Thank you Sebastian for reading. Our health is very important, and we owe it to ourselves to take care of it. Also what we eat and exercise too. Do you engage in any form of exercise.

  3. Čuo sam za ovaj pripravak za mršavljenje da je dobar. Nisam ga još probao, ali namjeravam ga isprobati. Uloga jetre na tijelu je jako velika. Čitala sam o masnoj jetri i ako osoba ima takve probleme ne može smršavjeti dok ne očisti jetru od masnoća Teško je održavati dobru liniju pored mnogih namirnica koje su danas dostupne u trgovinama.

  4. This article was perfect and well thought out! To many times i click onto sites and can’t truly understand what is being said because of the wording. You made this easy for me! And i couldn’t agree more nutrition is important.

    I did not know the term we are what we eat was in fact an accurate description or that there was so much to the digestion of what we eat! Thank you for this I’m definitely sharing this!

  5. Wow Eunice, you’ve just taken me on one incredible journey. My understanding, from hours of biology at school, was in no way as comprehensive as this description. I now have a much better appreiation for how our bodies work and work is the right word, for sure.

    Having this new found knowledge actually strengthens my resolve to have a proper balanced diet. Certainly one that aids our systems, rather than hinders them. I’m sure the majority of processed food items, would make the job far more complicated and time consuming.

    I have heard that we feel tired after a big meal because all of our energy is being diverted to our digestive system, Keeping our portions to a reasonable size would certainly be a welcomed addition, I would think. The other thing I have considered is only eating similar or the same food groups at one sitting. This sounds like it could help with digestion.

    • Hi Twack Romero, thank you for reading. Am happy you enjoyed reading my article. It is amazing what happens to what we eat. We really need to take care of what goes down our mouth.

  6. Oh Eunice… The whole concept behind what happens to the food we eat is so freaking complicated but amazing and I never bothered so much about it. However, it is something to really ponder about a bit. I can see that our saliva play important roles in the whole process. Our brains partake in a lot of the whole process too.

    It’s really important to watch what we eat because we’re exactly the food we eat. Thanks for sharing this…

    • Hi MrBiizy, thank you for reading. we really need to take care of what goes into our mouth, is quite a lot of process that it goes through. 

  7. Hey, I enjoy a lot while reading your guide on what happened with the food we eat. While reading I know that Anyone who has ever had the unpleasant experience of vomiting knows that the stomach is nothing less than a vat of acid. So for several hours the food churns in hydrochloric acid and enzymes. The liver comes to the aid of enzymes present in the intestine by producing bile—a yellowish alkaline fluid. Now I understand it well. Hope everyone will understand.

  8. Thank you for this informative article.
    I am struggling with my weight and general health and few friends has recommended keto for healthy living. I was abit sceptical about it, but your website has enlightened me. I will keep you posted on my keto journey.

Leave a Reply

Your email address will not be published.


*