Biology for dummies

[Saz94]

Can someone please explain this to me in simple terms (I'm in crash, poor cognition):

Are all nutrients absorbed in the small intestine or does the stomach absorb some too?

It seems that at least some medications are absorbed in the stomach? Considering how quickly they can act. Can I access a list somewhere of which medications are absorbed in stomach and which in small intestine?

What about supplements? E.g. vitamins, minerals, but also botanicals such as turmeric.

Please include a line break in between each sentence of your answer.

 

[wigglethemouse]

From google
https://www.livestrong.com/article/436603-in-which-digestive-organ-are-nutrients-absorbed/

The small intestine is the main area of the GI tract for absorption. The small intestine has three separate sections, the duodenum, jejunum and ileum.

Most nutrient absorption takes place in the duodenum and jejunum.

The duodenum absorbs carbohydrates, proteins, and minerals including calcium, magnesium, iron, chloride, sodium and zinc.

Remaining starches in the form of glucose or proteins passed from the duodenum are absorbed in the jejunum in addition to vitamin C, thiamine, vitamin B-2 and B-6, and folic acid, Escott-Stump reports.

The last section of the small intestine known as the ileum absorbs amino acids, fat, cholesterol and fat-soluble vitamins like vitamins A, D, E and K.

 

[wigglethemouse]

And
https://www.merckmanuals.com/professional/clinical-pharmacology/pharmacokinetics/drug-absorption

Theoretically, weakly acidic drugs (eg, aspirin) are more readily absorbed from an acid medium (stomach) than are weakly basic drugs (eg, quinidine).

However, whether a drug is acidic or basic, most absorption occurs in the small intestine because the surface area is larger and membranes are more permeable (see Drug Absorption : Oral Administration).

 

[Saz94]

Thank you wiggle

 

[Saz94]

OK. If drugs are mostly absorbed in the small intestine then how come some drugs can work very quickly? The first time I took Zopiclone, it started to affect me within 5-10 minutes!!! (Not placebo as I wasn't expecting it to feel how it felt)

And when I take potassium for muscle problems, my muscle function improves within 10-15 mins.

 

[wigglethemouse]

Potassium
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4963920/

Potassium is found in most plant and animal tissues, with fruits and vegetables having a higher nutrient density than cereals and animal foods.

Potassium is intrinsically soluble and quickly dispersed in the luminal water of the upper digestive tract.

The small intestine is the primary site of potassium absorption, with approximately 90% of dietary potassium being absorbed by passive diffusion [29].

Little is known about the bioavailability of potassium, with the majority of work being centered on the assessment of urinary potassium losses after potassium salt supplementation [30,31,32].

 

[Forbin]

From the Wikipedia article on the stomach.

Absorption[edit]
Although the absorption in the human digestive system is mainly a function of the small intestine, some absorption of certain small molecules nevertheless does occur in the stomach through its lining. This includes:

• Water, if the body is dehydrated
• Medication, such as aspirin
• Amino acids[24]
• 10–20% of ingested ethanol (e.g. from alcoholic beverages)[25]
• Caffeine[26]
• To a small extent water-soluble vitamins (most are absorbed in the small intestine)[27]

The parietal cells of the human stomach are responsible for producing intrinsic factor, which is necessary for the absorption of vitamin B12. B12 is used in cellular metabolism and is necessary for the production of red blood cells, and the functioning of the nervous system.

Nitroglycerin can be absorbed through the lining of the mouth.