Absorption of Food: Factors & Timeframes

In summary, sugary substances are advised to be consumed in order to receive an "energy boost". The stomach empties completely in about 1.5 hours and food that is liquid leaves the stomach fastest. Drugs and pills are absorbed through the stomach wall within a few hours. The pyloric sphincter controls the passage of food from the stomach to the small intestines and old and weak muscle is suspect to edemas.
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Simfish
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If people are advised to take an "energy boost", so to speak, they're advised to take in sugary substances.

Yet, the thing is - all nutrients are absorbed through the small intestines. But does food stay in the stomach for a number of hours? And then, what factors control the passage of food into the intestines? Are these factors selective to a particular type of food (that is, are they more receptive to food that is broken up?) And in that case, do some nutrients (simple sugars, for example) quickly pass through the stomach and into the intestines?

What of drugs and pills? How long do they need to be digested before absorption?
 
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Some nutrients are absorbed to some degree through the stomach wall. Monosaccharides are an example - fructose, glucose. Water and some medications can do this as well. Example: Aspirin can be absorbed thru the stomach lining, but normally most of it goes into the small intestine.

The stomach empties completely in about 1.5 hours. Liquids leave the stomach fastest, so if you drink a soda a large percent of it leaves in 10-15 minutes.

Time to exit:
The deciding factor is whether the chyme (stomach juices + food chunks) is liquid or not. If you swallow a marble it may never leave the stomach. Assuming you can actually swallow one.
 
  • #3
If you swallow a marble it may never leave the stomach. Assuming you can actually swallow one.

But then what of the children who swallow them? I know that I ate chunks of paper as a child - and I think I swallowed legos too. =/

Also, the pyloric sphincter controls the passage of food from the stomach to the small intestines. The question, then, is well, when it opens in response to digested food, what is to prevent undigested food from passing through? Is it selective with respect to digested food?

And are the stomach muscle is usually strong enough to minimize the influence of gravity, right? On the influence of gravity, the densest and undigested particles are likely to be on the bottom. But yet, if we look at the diagram at http://en.wikipedia.org/wiki/Pyloric_valve , we can see that the valve is actually somewhat upwards (so then this might be an ideal outcome). Nonetheless, I don't think that standing upright can affect the stomach much.

On the other hand though, old and weak muscle is suspect to edemas - and I'm wondering if this is also true for the stomach.
 
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Related to Absorption of Food: Factors & Timeframes

1. What factors affect the absorption of food?

The rate of absorption of food is affected by various factors, including the type of food, the amount of food consumed, and the health of the digestive system. The composition of the food, such as the presence of fats, proteins, and carbohydrates, also plays a role in the absorption process. Additionally, certain medical conditions, medications, and age can impact the absorption of food.

2. How long does it take for food to be absorbed?

The time it takes for food to be absorbed varies depending on the type of food and the individual's digestive system. On average, it takes 6-8 hours for food to completely pass through the small intestine and be absorbed into the bloodstream. However, some foods, like simple carbohydrates, can be absorbed within minutes, while others, like proteins and fats, can take several hours.

3. What is the role of enzymes in food absorption?

Enzymes play a crucial role in the absorption of food. These proteins help break down complex nutrients into smaller molecules that can be easily absorbed by the body. For example, amylase breaks down carbohydrates, lipase breaks down fats, and protease breaks down proteins. Without these enzymes, the absorption of food would be significantly impaired.

4. How does the small intestine aid in food absorption?

The small intestine is the primary site for food absorption in the digestive system. Its lining is covered with tiny finger-like projections called villi, which increase the surface area for absorption. The villi are also lined with microvilli, which contain enzymes that aid in breaking down food. Additionally, the small intestine has muscular contractions that help move the food along and facilitate absorption.

5. Can certain lifestyle habits affect food absorption?

Yes, certain lifestyle habits can affect food absorption. For example, smoking can damage the lining of the small intestine, making it less efficient in absorbing nutrients. Excessive alcohol consumption can also impair absorption by damaging the cells in the small intestine. Additionally, regular exercise can improve digestion and absorption by increasing blood flow to the digestive organs.

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