Tag: insulin

Posted in Psychology & Medicine

Food Coma

Posted on by Jinavie

Why do we feel sleepy after we eat? There are two components to the so-called “food coma”: neurological and hormonal. When we eat, the food mashed up by your teeth is swallowed down the oesophagus and into the stomach, where it is churned in a vat of very strong hydrochloric acid. The acid dissolves the food into liquid form, which is then sent to the small intestines. Here, the chemical components of the food such as carbohydrates is broken into simpler blocks, such as glucose. This is then absorbed into the bloodstream.

The body can actually sense when you have swallowed food, as your stomach stretches and sends signals to the brain. This triggers the activation of the parasympathetic nervous system (opposite of the sympathetic nervous system, which is the “fight or flight” system). The parasympathetic nervous system is involved in digesting and rest. It stimulates stomach acid production, gut movement and even reduces your energy level so that digestion can happen smoothly. In old people, it can even decrease blood pressure enough to a point that they feel dizzy (much like head rush). This is the neurological component.

The hormonal component is linked with the absorption phase of digestion. To deal with the increasing level of glucose in your blood, the pancreas secretes insulin. Insulin rounds up the glucose in the blood and stores it away in cells to normalise the blood glucose level. In this process, it also stimulates the uptake of certain amino acids (building blocks of protein) into cells. However, it leaves out one type of amino acids called tryptophan. Because there is more tryptophan in the blood compared to the other amino acids, your brain decides to use this to build more proteins. Tryptophan is converted in the brain into a very important neurotransmitter called serotonin, which is then converted into melatonin. Melatonin is a neurotransmitter involved in triggering sleep. Therefore, through this extremely complicated pathway, food causes sleepiness.

At face value, this makes it look like increasing intake of tryptophan may help induce sleep. It is commonly said that turkey meat and bananas help you sleep because of tryptophan. But this is an urban myth as neither of these foods are particularly high in tryptophan and there is no evidence to suggest that tryptophan itself helps you sleep. Then again, melatonin supplements have some evidence supporting it as a sleep aide. This shows just how complicated the human body can be.

Posted in Psychology & Medicine

Viscera: Pancreas

Posted on by Jinavie

(Learn more about the organs of the human bodies in other posts in the Viscera series here: https://jineralknowledge.com/tag/viscera/?order=asc)

The pancreas is probably the most central organ in the human body. It is situated just under the liver and stomach, surrounded by the duodenum (first part of small intestine) and lies in front of the aorta. It is shaped like a fish and thus is divided into parts named the head, neck, body and tail. The head of the pancreas tucks into the loop of duodenum and drains its contents via the pancreatic duct, which joins with the common bile duct (from the liver and gallbladder).

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The function of the pancreas is divided into two functions: exocrine and endocrine.

An exocrine gland is an organ that excretes its products out of the body (including the intestines), such as the salivary or tear glands. The exocrine function of the pancreas is the production and secretion of digestive enzymes that break down proteins, fats and carbohydrates in the small intestine. Because of this, injury to the pancreas often causes a leak of this digestive juice, causing the body to self-digest the pancreas (leading to pancreatitis) and surrounding organs.

An endocrine gland is the opposite in that it secretes its contents into the bloodstream. These glands typically produce hormones, such as the thyroid, ovaries and adrenal glands. The pancreas’ endocrine function is related to an extremely common yet deadly disease: diabetes. Within the pancreas, there are millions of cells that cluster into groups called islets of Langerhans. There are various types of cells, but the most common are the alpha-islet cells that secrete glucagon and beta-islet cells that secrete insulin. Insulin acts to lower blood sugar (glucose) levels by promoting storage and use of glucose after a meal. Glucagon acts to increase blood glucose by promoting the breakdown of glucose storage units (glycogen) and the production of more glucose by the liver. Diabetes occurs when beta-islet cells fail to produce insulin because they are destroyed by the immune system (type 1 diabetes mellitus) or become desensitised by chronically elevated blood glucose levels (type 2 diabetes mellitus).

Another important disease concerning the pancreas is pancreatic cancer. Pancreatic cancer is notorious for its deadliness as it carries a 5-year mortality rate of over 95%. This is because it usually remains hidden – without any symptoms – until it as grown substantially and spread to other organs. However, this prognosis only applies to the most common type of pancreatic cancer involving exocrine cells (adenocarcinoma). There are far rarer cancers of the pancreas that involve the endocrine cells (e.g. insulinoma), which tend to have extremely good prognoses and are usually curable.

Steve Jobs (founder of Apple Inc.) had this kind of pancreatic cancer – an islet cell neuroendocrine tumour. Despite his excellent chance of cure with chemotherapy and surgery, he refused treatment for nine months and instead relied on alternative medicine for cure. However, his disease worsened and he finally resorted to having surgery. By this stage, his disease had spread to the liver due to the nine-month delay in treatment. Spreading of cancer is called metastasis and is often an indication that the cancer is no longer curable. Jobs went against his doctors’ advice and opted for a liver transplant in the hopes of curing his cancer. Organ transplant involves suppressing the patient’s immune system (which also keeps cancers in check) to prevent rejection of the donor organ, which is why oncologists advise against transplants in cancer patients. Jobs’ condition deteriorated quickly after his liver transplant and his decisions ultimately led to his demise.

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Posted in Psychology & Medicine

Munchausen’s Syndrome

Posted on by Jinavie

Some people are known to overreact regarding their health, such as a hypochondriac thinking that she has kidney failure because her urine looks slightly frothier. However, some people far surpass the level of hypochondrias to the level of psychiatric disease.
Münchausen’s syndrome patients are known to exaggerate or create symptoms so that the doctor would pay attention to them. When the doctor investigates, treats and sympathises with the patient they gain satisfaction from all the attention they are receiving.
Although this may sound like hypochondrias, Münchausen’s is far more serious.

A Münchausen’s patients are known to cause symptoms just to get attention from others. For example, a common manoeuvre used is the injection of insulin to induce a hypoglycaemic seizure. When their symptoms are “treated”, the patient will most likely invent another factitious disease to be treated for a longer time. They will also seek out many different doctors when the attending doctor catches on to their act. In fact, a Münchausen’s patient will do almost anything to prolong medical care, even accepting unnecessary and risky procedures such as surgeries.

The key difference between Münchausen’s syndrome and hypochondriasis is that the patient is aware that they are not actually sick (hypochondriacs actually believe they are sick). The fundamental basis for Münchausen’s syndrome is the desire for attention. Thus, the main risk factor for developing Münchausen’s is childhood experience of seeing someone close (typically a family member) suffering a debilitating disease. For example, if a girl sees her sister suffering from leukaemia and receiving all the attention of everyone around her, she may develop feelings of jealousy and later try to duplicate the scenario. As a patient, the person feels safe and comfortable and this feeds their addiction to medical care.

As Münchausen’s patients are very proficient liars and act completely like an actual patient, doctors must rule out any diseases before suspecting that their patients have a psychiatric problem. However, some signs such as the patient being overly keen on receiving procedures such as biopsies or continuously developing random symptoms may indicate Münchausen’s.

Interestingly, a similar condition called Münchausen’s syndrome by proxy also exists, where a caregiver (e.g. mother) convinces a doctor that the person they are caring for (e.g. child) are sick. Unfortunately, as these patients actually cause illness in the child, it is considered a form of child abuse. Common “symptoms” include: growth problems, asthma, allergies, vomiting, diarrhoea, seizures and infections. This may lead to the child developing Münchausen’s syndrome in the future.

Posted in Psychology & Medicine

Insulin

Posted on by Jinavie

Diabetes is a common and serious disease that is caused by the body being unable to control the blood sugar (glucose) level, leading to severe organ damage. For example, blood vessel damage can lead to blindness, renal failure, heart attacks or strokes. Diabetes is divided into Type 1, caused by the destruction of pancreatic β-cells (that produces insulin) leading to insulin deficiency, and Type 2 diabetes, where insulin resistance renders the hormone useless. Thus, diabetes is a disease related to insulin. So what is insulin?

Insulin is a hormone that lowers blood glucose. It has the important function of controlling blood glucose levels after a meal. Therefore, a diabetes patient has high blood glucose, which has a toxic effect.
As type 1 diabetics cannot produce insulin, they require daily insulin injections. Some type 2 patients also need insulin. But this hormone that saves the lives of diabetics also has a deadly dark side.

Too much insulin leads to hypoglycaemia due to its blood glucose lowering properties. This is the opposite of what happens in diabetes, but is even more dangerous. Although there are in-built autonomic defence mechanisms to prevent this from happening, a high level of insulin can overcome this to cause blood glucose to plummet. 
A hypoglycaemic patient initially suffers cognitive dysfunction, then sweating and tremors. As blood glucose falls further, the patient begins to convulse, until they fall into a coma and eventually die. This is because the brain heavily relies on glucose for its functions, and a disruption of glucose supply causes it to shut down.
Because blood glucose fluctuates much like blood pressure, it is hard to control. This leads to many diabetics accidentally falling into hypoglycaemia, or even losing their lives. Furthermore, insulin is sometimes used by people to cause hypoglycaemia as a means of suicide.

If you see a person convulsing, check around for any hypodermic needles or bottles of insulin. A diabetic patient would have a medic alert bracelet, and if it is a suicide attempt they would have recently injected themselves with insulin. If you think it is hypoglycaemia, you must immediately treat the patient as severe complications can occur in a very short time. The emergency treatment is quite simple – raise the blood glucose. For example, dissolving a spoon of white sugar in the patient’s mouth or making them drink a sugary drink such as apple juice can cause a spike in blood glucose, causing the symptoms to disappear. If their consciousness does not return, you may need to repeat the process until their blood glucose is high enough.

Knowing even a little about insulin and hypoglycaemia may lead to you saving a person’s life someday.

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