Vitamins are organic nutrients that you and I need in small but healthful quantities. Almost all vitamins are extracted from the food we eat or supplements we take since the human body does not have the capacity or ability to synthesize or store these compounds. So, unlike regular carbs, proteins or fats ( lipids ), the body relies on how often you can avail vitamins via your dietary regimen to meet the demand of the various physiological processes that require these nutriments and minerals to be completed successfully. So that means that the question of how and where are vitamins absorbed is, more than ever before, very relevant to anyone who is looking to lead a healthy and problem-free life.
Where are Vitamins Absorbed? A Look at the Various Absorption Sites of these Life-giving Nutriments
As you may already know, different nutrients extracted from your diet or supplements have different optimum absorption sections in the gastrointestinal tract. The reason for this simple, the GI tract is adapted differently to assimilate a wide diversity of nutrients that may be availed by the digestive enzymes from the food you take. It is this unique diversity that has enabled human beings to have one of the most specialized digestive systems in the Kingdom Mammalia. So specialized it is that human beings have been able throughout the history of mankind to survive on a broad range of dietary input, starting from meat all the way to plant matter, tubers and grains.
That aside, where are vitamins and minerals absorbed?
The short-form answer to the question is mainly in the small intestines but also in the large intestines aka the colon. But it is not as straightforward as that. For starters, the small intestines is composed of at least 4 subsections, each of them thoroughly specialised and adapted for the extraction and subsequent assimilation of different vitamins. With that in mind, here is a quick premise to the precise locations where vitamins are primarily absorbed in the intestinal lining.
The chyme from the stomach enters the duodenum via the cardiac or esophageal sphincter where it is exposed to a combination of secretions adapted to aiding digestion. This secretion includes enzymes, bile salts, and host bicarbonate based acids. The bile salts, which as a matter of fact emanated from the liver, help digest fat-soluble vitamins and a variety of lipids. The fat soluble vitamins, in this case are vitamins K, E, D and A. And, while the pancreatic enzymes from the pancreas assist in digesting fats and carbohydrates, the bicarbonate from the same organ is responsible for the neutralization of acidic remnants from the stomach. And, this sets up the stage for the absorption of the nutrients extracted from the earlier stages of digestion.
The digestion and absorption process continues with chyme transitioning from duodenum to the jejunum. This is actually the smart middle or second part of the small or minor intestines. Here, the 1st half of the jejunum is responsible for the absorption and assimilation of close to 90% of the nutrients which includes minerals, vitamins, carbohydrates and other assorted organic compounds.
iii. The ileum
If you have been struggling with the question of where are b vitamins absorbed, worry no more. The ileum, which is in fact the last section or specialized segment of the small intestine before it joins the colon, absorbs bile salts, water and vitamin B12. Of importance, however, is the ileocecal valve which is located between this part of the small intestines and the caecum. This valve helps to control the movement of contents from the ileum to the colon. It is structured in such a way that it increases the contact time of electrolytes and nutrients with the last part of the small intestines. The electrolytes, in this case, refers to the conglomerate of essential minerals that the body needs to keep functioning as it is supposed to.
What's more, the sphincter also prevents reflux (back-flow) from the caecum up into the ileum thereby restricting the movement of bacteria and other unwanted substances from the colon into the last part of the small bowel.
How are Vitamins Absorbed - A Insight into the Mechanism Behind the Extraction of Some of the Most Important Parts of your Dietary Regimen
Eating a balanced diet is a universally agreed-upon requirement for leading a healthy life. And, sometimes, it is also necessary to top this up with a supplement to fill any nutritional dietary gaps. Nethertheless, it goes without saying all this is useless if your body cannot figure out a way to exhaustively extract, absorb and assimilate these important micronutrients. So how are vitamins absorbed from our dietary or supplementation input?
Even before delving so much on the question of how are fat soluble vitamins absorbed or how are water soluble vitamins absorbed in the body, it is important to draw the entire digestion picture. You see, after food has been chewed thoroughly and swallowed, the combination of hydrochloric acid in the stomach and a consortium of enzymes works to breakdown fats, carbohydrates and proteins. From here, the inner lining of the digestive system extracts the vitamins and minerals from the chyme (digested food) and assimilates them into the bloodstream. These absorbed nutrients are availed to the cells to furnish their needs through a series of complex biochemical reactions.
Vitamin and mineral intake, nevertheless, is just one side of the story. Contrary to what most people know, sometimes your body requires the presence of certain nutrients to be able to absorb and assimilate certain vitamins into the bloodstream or atleast transport them to the cells where they are required efficiently. This is actually the tricky part of answering the question of how are water soluble vitamins absorbed.
Look at this: Vitamin C, for instance, plays an immense role in the absorption and assimilation of chromium and iron in the body. Copper, on the other hand, is needed in the absorption process of zinc and iron. And, without vitamins K and D, absorbing calcium would be a tall order regardless of how much fresh milk we take or bone broth we eat. The same is true for fluoride and magnesium. In other words, the optimum assimilation and absorption process of micronutrients is a delicate intricate balance of various interdependent factors.
That being said, there is a combination of many other factors that can obstruct or aid the absorption process of micronutrients. If your body, for instance, is deficient in certain minerals or vitamins, then it goes without saying that it will be absorbed more aggressively from your diet than one that you are not lacking. This is why fitness enthusiasts are advised to eat only a few hours before working out since the high demand for nutrients in the muscles could easily throw the digestion and absorption process into a disarray hence hampering the assimilation of certain types of nutrients.
With this same reasoning, it is easy to see why chronic stress can negatively affect the rate and quality of the absorption of micronutrients. This is actually the reason it becomes harder to sport that healthy and glowing contenance the longer you grapple with long-term mental pressure. It is, therefore, advisable for you to seek healthy stress outlets to keep your vitamins and minerals absorption balance at optimum levels.
Absorption of vitamins is also impacted negatively by heavy alcohol or caffeine intake. In fact, experts believe that heavy use of depressants and stimulants can reduce the assimilation rate of important micronutrients by more than 80%. Alcohol, in particular, can inhibit the digestion and breakdown of food sources into usable micronutrients by hampering the secretion of various important digestive pancreatic enzymes. It can also impair the absorption of vitamins after damaging the inner sensitive lining of the stomach or intestines thereby disabling the movement of certain micronutrients from the chyme to the bloodstream.
Heavy caffeine use, on the other hand, can affect certain nutritional deficiencies by restricting easy absorption of certain vitamins. And, it does not end there. You see, even if the micronutrients are somehow absorbed into the bloodstream, the presence of caffeine or alcohol can greatly prevent them from being fully assimilated by altering their utilization, storage, transport and excretion. Decreased liver stores of micronutrients like vitamin A, for example, is common among long-term alcoholics as do the excretion of fats and folates. All the more reason to take it easy whenever you go out.
That aside, the dietary intake of the food from which the nutrients are being extracted also has a significant bearing on how readily they're assimilated and absorbed. Fat soluble vitamins such as K,E, D and A will be better absorbed if they are being extracted from a meal that already contains a plentiful amount of healthy fats. Therefore, it goes without saying that your body will have a harder time absorbing these fat-soluble vitamins if you are on a low-fat diet.
Speaking of which, foods that are rich in fat-soluble vitamins include;
- Fish liver oil
- Cheese, fermented milk and other assorted dairy products
- Sweet potatoes
- Peanut butter and quality margarine
What Happens to Vitamins that Aren't Absorbed?
As discussed earlier, the small intestines are responsible for absorbing and assimilating nutrients from the food eaten and facilitating the transportation to the bloodstream. After this, they are further processed before being distributed to constituent cell structures all over the body, including your skin, hair, bones and other major organs. So, it is likely that one would wonder, what happens to vitamins that aren't absorbed?
Well, to get to the bottom of the fate of vitamins from pills that aren't absorbed it is important to first shed some light on why this would happen in the first place - malabsorption syndrome. This refers to a collection of disorders that affect your illeum's ability to absorb or assimilate optimum levels of certain minerals, electrolytes and nutrients. This could include macronutrients such as fat, carbs and proteins, as well as lesser-known but still important micronutrients such as minerals or vitamins.
The causes of vitamins malabsorption revolves around digestive enzymes and whether or not they work as they are required to, for minerals and vitamins to find their way to the bloodstream. Other causes include;
- Lactose intolerance;
- Damage to the ileum, mostly in the aftermath of an infection, chronic inflammation, surgery or trauma;
- Crohn's disease, celiac disease, chronic pancreatitis;
- Long-term or very frequent use of antibiotics;
- Liver, gallbladder or pancreatic cancer;
- Medications or treatment therapies that may damage the inner lining of the small intestines such as radiation therapy aimed at treating certain cancers or tetracyclines;
- Parasitic infections.
As you would expect, the minerals and vitamins that the body is unable to extract from the diet are simply lost as waste alongside roughages, excrement and other indigestible stuff. And this goes to show how important it is for you to ensure that your digestive system is working as it should for you to optimize the absorption of micronutrients from either your dietary intake or supplementation regimen. This leads us to the final part of this discourse.
How to Take Vitamins so that They are Absorbed
One of the easiest ways of improving our minerals and vitamins' absorption rate is by eating a combination of nutrient-rich foods in each sitting or meal of the day. You see, a variety-rich diet improves the chances of pairing up certain micronutrients together to trigger easy take up of others. Vitamin C, for example, is usually a prerequisite for the absorption of iron. Thus, eating tofu or legumes alongside oranges, capsciums, cauliflower or chilli increases the conversion rate of nonheme iron into a better bioavailable version. This also breaks the monotony of eating the same thing for lunch or breakfast every other day.
Another recommended way of taking vitamins so that they are absorbed is including healthy fat-rich foods in our daily dietary plan. Fat soluble vitamins such as K,E, D and vitamin A need an oil-based medium to be absorbed and assimilated efficiently. Adding avocados, nuts, seeds to fruit salads and vitamin-rich meals is a wonderful and quite palatable of ensuring maximum nutrient uptake.
Besides that, nourishing your gut with a probiotic such as kombucha, sauerkraut or kefir to introduce healthy bacteria is a recommended way of availing nutrients from the food we take every day. You will also be improving your digestion and getting a handle on any constipation-related issues while at it. Speaking of which, steer clear of tea during and immediately after mealtimes. As much as tea might contain useful polyphenols and other organic compounds that could tone down the risk of developing some chronic illnesses, it is likely to hamper the uptake of iron and other assorted vitamins.
Lastly, take a break from caffeine, alcohol and diuretics to give your body the best shot at digesting food and absorbing the nutrients availed as effectively as possible. Instead, try to incorporate vegetables and fruits that have a rich-collection of natural digestive enzymes such as papaya, pineapple and specific mushrooms. Hydrate and learn how to manage your stress levels white at it too.