Effect of Starvation on Human Body

In this article, we will discuss the phases and effects of starvation on the human body. Starvation can be defined as a severe deficiency of nutrients and calorie intake. Starvation can also be defined as an extreme of malnutrition in which the caloric level of the body goes way below its standard requirement. The fundamental cause of starvation is an imbalance between food or nutrition intake and physical effects.

Starvation affects all body organs differently through different phases. A log standing starvation can cause permanent damage to the organs. Even worst, hunger can also cause death.

One must remember that starvation is not an event; it’s a process. After the intake of food is stopped, our body utilizes some energy reserve molecules. After those energy reserves of the body decline, the chain of metabolic changes starts.

Stages of Starvation

Usually, the symptoms and effects of starvation are divided into three stages. The symptoms of stage 1 and stage 2 of starvation in anyone who skips meals for fasting or weight loss. The symptoms of these two initial stages are not severe. The symptoms of the third stage of starvation are severe and can lead to death. The third stage of starvation is not an intended activity; it results from an inability to reach out for food. A brief review of the three stages of starvation is in the following section.

Phase 1

The first phase of starvation starts when someone skips his meals. As you do not take in any food, the sugar level of the body goes down. As blood glucose level goes down, the calories required for the body’s normal functions also deplete because glucose is the primary molecule broken down to get energy.

During the first phase of starvation, the body maintains blood glucose levels by increasing the new glucose production from the live and kidneys. Some glycogen stored in the liver is also broken down to glucose to maintain its average blood concentration. Additionally, fats and proteins are used as a source of energy.

Phase 2

Phase 2 of starvation lasts from one week to two weeks. During phase 2, the body’s fat reserves are the primary source of energy for the body. Fats are converted into ketones in the liver through metabolism. These ketones are then used as an alternative source of energy.

Phase 3

By that time, all the fat reserves of the body also deplete. After the depletion of the fat reserves, our body turns to the tissue proteins to utilize them as a source of energy. The proteins of the muscles are also broken down, which leads to the atrophy of the muscles. The end result of starvation can be death. When proteins are drained from the cells, they can no longer survive. Infection during the third stage of starvation can further speed up the process of life decline. In this stage, the body does not have a strong immune system to fight any infection.

Effect of Starvation on the human body

The severity of different effects of starvation on the body depends on the duration of the starvation. The usual symptoms of starvation include fatigue, headache, dizziness, behavioral changes, weight loss, abdominal discomfort, and reduced blood pressure. A detailed description of the different effects of prolonged starvation is in the following section.

1) Initial Metabolic Changes

The very initial metabolic changes are an effort of the body to maintain blood glucose concentration to meet calorie requirements. The process of new glucose synthesis of glucose from the liver and kidney is started. Typically, the surplus glucose in the body is stored in the form of glycogen. During starvation, the glycogen is broken down into glucose which is used for different body functions. Additionally, when starvation lasts for days, the process of fat breakdown also sets. The fats are used to keep the calorie level of the body in an appropriate range.

2) Muscle Atrophy

Muscle Atrophy or muscle wastage does not usually occur during phase 1 and phase 2 of starvation. However, as the glycogen and fat reserves of the body start to deplete, the Body shifts to proteins to fulfill its energy needs. The proteins from various types of cells are broken down to get energy. Muscles are the cells of the body that contain the highest amount of proteins. As starvation lasts for weeks, the proteins of the muscles are broken down to get energy. The ultimate result is decreased muscular mass, which is termed muscle atrophy.

3) Endocrine Effects

Starvation affects almost all the hormones of the body. If a child faces starvation, his onset of puberty will be delayed. Additionally, in children who face starvation, the release of growth hormone is also reduced. A reduced release of growth hormone and reduced availability of the nutrients result in stunted or reduced growth. There is an irregular release of thyroid hormone during starvation. Additionally, the release of cortisol or stress hormone is increased during starvation.

Starvation also affects the reproductive hormones to an enormous extent. It can affect the fertility of both genders equally. If a woman of reproductive age faces starvation, she will have menses-related issues. She might face irregular periods; there can also be a complete stoppage of the menstrual cycle. If a woman gets pregnant despite starvation, it is unlikely to give birth to a healthy child. The baby will probably be aborted at the initial stages due to lack of nutrition and uneven production of female reproductive hormones.

4) Effect on Cardiovascular System

Cardiovascular System is affected through different mechanisms during starvation. As the body’s energy levels go down, the heart rate and contractile force are reduced. A changing hemodynamic situation can also lead to life-threatening arrhythmias. A severe decrease in the heart’s pumping capacity can also cause fainting because of a reduced supply of oxygen and nutrients to the brain.

During starvation, there is also a reduced intake of sodium and potassium. This decreased intake of sodium and potassium causes an electrolyte imbalance. A reduced concentration of these solutes in the blood causes the plasma to diffuse into the blood vessels’ interstitial tissue. The diffusion of plasma in interstitial tissue causes edema. The amount of blood flowing in blood vessels is reduced. The ultimate result of decreased blood volume and decreased heart pumping capacity is lowering blood pressure.

5) Effect on Gastrointestinal Tract

During starvation, there is an overall decrease in the activity of the gastrointestinal tract. The mobility of the gut is reduced, which leads to constipation. The caliber of the gastrointestinal tract is also reduced during starvation, which gives you a sense of fullness despite having no food. The salivary glands may be swollen during starvation. The enzymes produced by salivary glands are not utilized because of reduced intake of food which leads to swelling of salivary glands. There can be stomach discomfort and a feeling of acidity.

6) Effect on Brain

Starvation also has some neuro-psychiatric effects; the result is overall reduced working capacity of the brain. Most of the thinking process during starvation is limited to anorexia Nervosa, limiting concentration and focus on other activities. A combined disturbance of neurons and stress hormones can also cause psychiatric issues such as depression and anxiety.

7) Bone Resorption and Reduced Blood Cell Production

During the third stage of starvation, the bone mass and bone strength also reduce. The reduced intake of food also reduces the concentration of different minerals, including calcium and iron. A reduced calcium deposition leads to weakening of the bones, and a reduced iron concentration leads to decreased production of RBCs.

8) Skin Damage

During starvation, the skin becomes dry and cracking due to dehydration, making it more liable to bruising. Reduced blood pressure reduces blood flow to the skin, due to which the toxins cannot be removed from the skin. The ultimate result is tanned skin and the formation of pressure sores. The wound healing capability of the skin is also reduced because of the insufficient availability of the building materials for new cells.

9) Hair Problems

During starvation, the hair becomes dry and thin. The ultimate result is premature hair fall. During starvation, there can also be inappropriate growth of fine, downy hair on the body to protect against cold.

10) Cold Intolerance

During starvation, the resting metabolic rate of the body is very low. Our body produces heat during metabolism, which helps us cope the cold conditions. However, the unavailability of food and reduced basal metabolic rate causes cold intolerance during starvation.

Reduced blood pressure, reduced blood volume, and electrolyte imbalance can lead to kidney and liver failure. There can also be severe cardiac arrhythmia due to electrolyte imbalance. All these events can result in death which is the end result of long-standing starvation.

The Takeaway Message:

Starvation is a severe lack of nutrients or calories in the body. Starvation starts from missing a meal and progresses through three phases. Phase I and phase II of starvation are experienced by anyone who misses his meals. During phase 1 and phase 2, there are no major harmful effects on the body except some metabolic changes. In these phases, the body starts to use proteins and fats as energy instead of carbohydrates.

The third stage of starvation badly affects almost all the organs of the body. It causes electrolyte imbalance and dehydration. During the third phase of starvation, the functioning of the brain and cardiovascular system is also affected. There are hormonal disturbances in phase 3 of starvation which can also affect fertility. In this phase, the integrity of the skin and gastrointestinal system is also affected.