Posted in Psychology & Medicine

Viscera: Small Intestine

(Learn more about the organs of the human bodies in other posts in the Viscera series here:

Abdominal organs are often grouped into the colloquial term gut. “Gut” also refers to a specific organ – the small intestine (or small bowel). It is an important part of the gastrointestinal (digestive) tract, connecting the stomach to the colon and involved in digesting and absorbing nutrients. The small intestine is extremely long, roughly 7m in an adult. It fits in the abdomen by folding and packing neatly, lying under the liver, stomach and pancreas while being framed by the large intestine. The small intestine is not freely hanging so you cannot just pull it out like a rope. It is connected to the body by a fan-like membrane called the mesentery, which provides blood supply to the gut. The mesentery is attached along one side of the gut the entire way through.

The small bowel is composed of three parts: the duodenum, jejunum and ileum. Although people think digestion mainly happens in the stomach, it is actually primarily performed in the duodenum. The duodenum not only receives liquefied food from the stomach, but is also the place where the pancreas and liver drain digestive juices such as pancreatic enzymes and bile. The enzymes breakdown large molecules like fat, protein and carbohydrates into smaller building blocks, while bile acts like detergent to allow fat to mix better with water (emulsification).

The digested food then travels down the GI tract through a process called peristalsis, where the gut squeezes behind the bolus of food to push it forward, much like squeezing toothpaste out of the tube. The broken down products are mainly absorbed in the second part of the bowel (jejunum) via the walls. The small bowel wall looks like a carpet due to microscopic finger-like projections called villi. Villi allow for a much greater surface area for enhanced absorption. In coeliac disease, these villi are flattened by an autoimmune process and the patient cannot absorb as much nutrients (including vitamins).

By the time the food reaches the ileum, most of the nutrients have been absorbed. The ileum finishes the job by absorbing some extra things like vitamin B12 and bile salts, then sends the food through the ileocoecal valve, which is the door between the small and large intestine.

The small bowel is used by various cultures for culinary purposes. Other than simply eating the bowel itself after cooking, it is often used to pack different meats or other food inside, such as sausages or soondae (Korean sausages, filled with chop sui noodles).

Posted in Psychology & Medicine


Spinach is a vegetable that is excellent for your health as it is rich in nutrients such as vitamins and minerals. If you ask someone the first two things that come to mind regarding spinach, they will most likely reply Popeye and iron. Popeye is a cartoon that began airing in the 1930’s and every child knows that the man gains superhuman powers from eating a can of spinach. In fact, after Popeye began airing, US consumption of spinach grew 33%. Most people believe that Popeye gains powers due to spinach having a high iron content. Thus, adults always tell children that if they want to be as strong as Popeye, they must eat their spinach.

Unfortunately, eating spinach does not make you as strong as Popeye. In fact, it is not even related to iron either. Firstly, the reason why Popeye eats spinach was because the producers wanted to advertise the high vitamin A content in spinach. Furthermore, spinach does not have a high iron content. The spinach iron myth originated from a German scientist named Emil von Wolff. In 1870, von Wolff was analysing the nutrition contents of different foods when he, from severe fatigue, accidentally misplaced a decimal point while recording the iron content of spinach. This led to spinach being known to have ten times the amount iron it actually has (to the level of red meat).

One problem with this is that this story is not true either. There are no detailed records of von Wolff’s experiments and no one knows if he misplaced a decimal point or not. The myth most likely originates from a 1980 article in The British Medical Journal that first brought up the story. Does that mean spinach is actually is a good source of iron? Wrong. Vegetarians often claim that spinach has iron levels close to red meat, but there is something about iron that they do not know. Many plants have a high iron content (it is found in chlorophyll which is used for photosynthesis), but this is mostly non-heme iron. There are two types of iron the human body can absorb: heme and non-heme. Heme iron can be used directly after absorption whereas non-heme iron needs to be metabolised by the liver to be usable. This takes a long time and is inefficient meaning it is far more effective to eat foods rich in heme iron. Plant iron is all non-heme iron while 40% of iron in red meat is heme iron, meaning it is a much better source of iron. Furthermore, spinach has a high oxalate content, which is an iron absorption inhibiting agent, making what little usable iron it has unabsorbable. 

In short, it is true that spinach has “iron” but as we cannot absorb it or use it, it practically has no iron content. But if you tell this to your parents and refuse to eat spinach, you may get into a lot of trouble.

Posted in Psychology & Medicine

Korsakoff’s Syndrome

It is a well-known fact that excessive drinking leads to a so-called “blackout”. This form of memory loss is common in normal people and cannot be seen as a major illness. However, there is another disease that can be caused by excessive drinking called Korsakoff’s syndrome. Strictly speaking, this is not caused by alcohol but due to a thiamine (vitamin B1) deficiency and is commonly found in alcoholics and malnourished patients (it has also been reported to be caused by mercury poisoning and after centipede bites in Japan).

The six characteristic symptoms of this syndrome are: anterograde (cannot form new memories) and retrograde (cannot remember old memories) amnesia, confabulation, lack of detail in conversation, lack of insight and apathy.

Korsakoff’s syndrome patients show a very peculiar behaviour. As stated before they suffer from both anterograde and retrograde amnesia so not only can they not remember the past but they cannot make new memories either. Ergo, the brain uses information from its surroundings and attempts to recreate the lost memories, the result being confabulation. Confabulation is essentially what happens when the brain tries to fill in blanks in memories with false information. Confabulation is seen in everyday life too with healthy people but in the case of Korsakoff’s patients the effects are significantly more profound. For example, if you ask a patient what she did yesterday, she may look at your horse-print tie and claim she was horse-riding. If you ask the same question an hour later without your tie and instead holding a book with a photo of a Ferris wheel on the cover, she’ll state that she was at the amusement park. As one of the leading causes of amnesia and confabulation, Korsakoff’s should be suspected in any alcoholic or very underweight patient who keeps changing their stories around. 

As previously explained, the disease is caused by thiamine deficiency – therefore, the treatment is administering thiamine. But if the syndrome has persisted for a long time, the brain injury may be permanent. Also, treating the underlying alcoholism and malnutrition is important. 

If the thiamine deficiency is prolonged, it may lead to another disease called Wernicke’s encephalopathy. This is known as Wernicke-Korsakoff’s syndrome and in addition to the above symptoms, the patient may also experience confusion, tremors, nystagmus, paralysis of eye muscles, ataxia, coma and can eventually lead to death. All because of a deficiency of a single vitamin.

Who said nutrition is not important?


(NB: Dory from Finding Nemo is one of the most accurate portrayals of amnesia in films)