What Is Ketosis? What Causes Ketosis?

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Main Category: Endocrinology
Also Included In: Nutrition / Diet;  Diabetes;  Obesity / Weight Loss / Fitness
Article Date: 02 Mar 2010 - 0:00 PDT

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Ketosis is a condition in which levels of ketones (ketone bodies) in the blood are elevated. Ketones are formed when glycogen stores in the liver have run out. The ketones are used for energy. Ketones are small carbon fragments that are the fuel created by the breakdown of fat stores. Ketosis is potentially a serious condition if keytone levels go too high.

However, when the body is in ketosis the individual tends to feel less hungry, and will probably eat less than he/she might otherwise do. The body switches from being a carbohydrate-burning organism into a fat-burning one. The fat stores become a primary energy source, and the person loses weight. That is why low-carb diets have become popular, and effective, especially among obese people.

The modern human body in most societies usually metabolizes glucose from carbohydrates for energy purposes, rather than energy from fat. If there is not enough glucose (from carbohydrates) in the bloodstream the body draws on fat stores for fuel, causing the appearance of ketones in the blood. Ketones are produced by the liver from fatty acids.

We need proteins and fats for building and repairing tissue and cells - proteins and fats can also be sources of energy. If necessary, the body can get all its energy from fats and proteins.

Our brain can use glucose or ketones for energy; it cannot generally burn fat for energy.

When there are plenty of carbohydrates in the body, it breaks them down into glucose, which is then converted into energy and transported into the cells of our body.

If glucose cannot be broken down, as may be the case if the insulin levels are too low, or if there is a lack of glucose, then the body has to break down stored fat and convert it into energy. Metabolizing fat raises blood ketone levels, leading to ketosis. Ketosis can occur with Type 1 diabetes (not enough insulin), alcoholism, starvation, and with a low-carb, high fat/protein diet.

Ketones consist of acetone, acetoacetate or beta-hydroxybutyrate. Very high ketone levels can be toxic, making the blood more acid, and may damage such organs as the kidneys and liver.

The human body tries to lower acetone (a ketone) levels by breathing it out, causing a sweet and fruity breath. We also reduce keytone levels by expelling them through our urine.

Ketogenic diet for the treatment of epilepsy - this is a high-fat and low-carbohydrate diet. It was first developed in the early 1900s. The diet makes the body burn fat for energy, rather than glucose. According to The Epilepsy Foundation, when carefully monitored it has been shown to help two in every three children who tried it. In fact, in one third of cases seizures stopped completely. Doctors don't know exactly why such a diet, which in fact mimics starvation by burning fat for energy, prevents seizures. Experts do not know why this diet does not work for everyone with epilepsy. Certain vitamins have to be added to the diet.

The ketogenic diet may have some side effects, including dehydration, constipation, and occasionally kidney stones or gall stones. There are some other side effects, all of which make careful monitoring important.

Ketosis for weight loss - as explained above, if the body can switch from being a carb-burning machine to a fat-burning one, the person loses weight. We store our fat, sometimes in undesirable places, such as our hips, buttocks, tops of thighs and our tummy. Carbohydrates cannot be stored like fat can. If our body is in carb-burning mode, we eat when carb (carbohydrate) levels go down, in order to get our energy. To achieve ketosis, the body must be on a high fat/protein and low carbohydrate diet. According to some organizations and experts, such as Dr. Atkins, with proper monitoring (urine dip stick, for example), levels of ketosis can be kept within safe limits and the dieter can reach his/her ideal bodyweight without suffering unbearable hunger.

There are certain risks on sustaining a prolonged high protein, low carbohydrate diet. If keytone levels are not monitored properly, there may be a strain on the kidneys, there is a higher risk of developing kidney stones because more calcium is excreted through urine, and there is a higher risk of osteoporosis. Some experts say there is also a higher risk of having unhealthily high cholesterol levels. However, several studies, such as this one have revealed that not only does a low-fat/high protein diet reduce cholesterol levels, but it also brings down blood pressure in individuals with hypertension.

Experts cannot agree on whether ketosis caused by a low carb/high protein diet is good or bad for humans. Some say it is dangerous. While others point to human evolution: during most of the time that humans have existed; we have been a hunter-gatherer species and have lived primarily in a ketogenic state for extended periods. There are many documented cases of human societies today that exist in a long-term ketogenic state. After a 2 to 4 week period of adaptation, human physical endurance is not affected by ketosis, according to studies - meaning that we do not necessarily need a high carbohydrate intake in order to replace depleted glycogen stores for exercise. This makes the argument more compelling that, in fact, we are designed to thrive at certain levels of ketosis.

Source: Wikipedia, The Epilepsy Foundation, Health Protection Agency (UK).

Written by Christian Nordqvist
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

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