Disruption of Homeostasis

Summary

Homeostatic imbalances can be caused by genetic, lifestyle, or environmental factors, or some combination of all three.

Review

What is the difference between deficiency and toxicity?What are the six factors that contribute to homeostatic imbalance?

 What happens if there's disruption?

If homeostasis is disrupted, it must be controlled or a disease/disorder may result. Your body systems work together to maintain balance. If that balance is shifted or disrupted and homeostasis is not maintained, the results may not allow normal functioning of the organism.

Disruption of Homeostasis

Many homeostatic mechanisms keep the internal environment within certain limits (or set points). When the cells in your body do not work correctly, homeostatic balance is disrupted. Homeostatic imbalance may lead to a state of disease. Disease and cellular malfunction can be caused in two basic ways: by deficiency or toxicity. Deficiency occurs when beneficial pathways are blocked and cells lack adequate quantities of vitamins or minerals. Toxicity occurs when cells have an excess of a toxin that poisons the cell. Cells are delicate and require concise levels of every necessary substance; levels that are too high and levels that are too low can be extremely dangerous. Cells undergo homeostasis to maintain the ideal levels, but, when homeostasis is interrupted, your body may correct or worsen the problem based on certain influences. In addition to inherited (genetic) influences, there are external influences that are based on lifestyle choices and environmental exposure. These factors together influence the body's ability to maintain homeostatic balance.

A commonly seen example of homeostatic imbalance is diabetes. In a diabetic, the endocrine system has difficulty maintaining the correct blood glucose levels, so diabetics must closely monitor their blood glucose levels, as shown in Figure below. They must monitor their daily sugar intake and regulate their blood glucose levels with insulin injections. Like most homeostatic imbalances, diabetes is dependent on both genetics and lifestyle.

Internal Influences: HeredityGenetics

Genes are sometimes turned off or on due to external factors, which we have some control over. Other times, little can be done to prevent the development of certain genetic diseases and disorders. In such cases, medicines can help a person’s body regain homeostasis. An example is the metabolic disorder called Type 1 diabetes, which is a disorder where the pancreas is no longer producing adequate amounts of insulin to respond to changes in a person's blood glucose levels. Insulin replacement therapy, in conjunction with carbohydrate counting and careful monitoring of blood glucose concentrations, is a way to bring the body's handling of glucose back into balance. Cancer can be genetically inherited or can result from a mutation caused by exposure to toxins such as radiation or harmful drugs. A person may also inherit a predisposition to develop a disease such as heart disease. Such diseases can be delayed or prevented if the person maintains a healthy lifestyle.

External Influences: LifestyleNutrition

For proper cell function, it is imperative that cells get the vitamins and minerals they need. These vitamins are obtained through our diet, and an imbalanced diet may increase one's risk of disease. For example, a menstruating woman with an inadequate dietary intake of iron will become anemic. Hemoglobin, the molecule that enables red blood cells to transport oxygen, requires iron. Therefore, the blood of an anemic woman will have reduced oxygen-carrying capacity. In mild cases, symptoms may be vague (e.g. fatigue), but, if the anemia is severe, the body will try to compensate by increasing cardiac output, leading to weakness, irregular heartbeats, and sometimes heart failure.

Physical Activity

Physical activity is essential for proper functioning of our cells and bodies. Levels of rest and physical activity both influence homeostasis. Inadequate sleep is related to a number of health problems such as irregular heartbeat, fatigue, anxiety, and headaches. Poor nutrition and a lack of physical exercise can lead to being overweight or obese; these conditions increase a person’s risk of developing heart disease, Type 2 diabetes, and certain forms of cancer. Staying fit by regularly taking part in aerobic activities, such as walking (shown in Figure below), has been shown to help prevent many of these diseases. 

Mental Health

Your physical and mental health are inseparable. Our emotions cause chemical changes in our bodies that have various effects on our thoughts and feelings. Negative stress (also called distress) can negatively affect mental health. Regular physical activity helps people cope with distress and has been shown to improve both physical and mental well-being. Among other things, regular physical activity increases the ability of the cardiovascular system to deliver oxygen to body cells including brain cells. For people who have more serious mental and mood disorders, medications that may help balance the amount of certain mood-altering chemicals within the brain are often prescribed. Medication is an external influence that can help stabilize homeostatic disruptions.

Environmental Exposure

Any substance that interferes with cellular function and causes cellular malfunction is a cellular toxin. There are many different sources of toxins including natural and synthetic drugs, plants, and animal bites. Air pollution, another form of environmental exposure to toxins, is shown in Figure below. Unfortunately, a commonly seen example of an exposure to cellular toxins is drug overdose. When a person takes too much of a drug that affects the central nervous system, basic life functions, such as breathing and heartbeat, are disrupted. Such disruptions can result in a coma, brain damage, and even death.

[Figure3]

Air pollution can cause environmental exposure to cellular toxins such as mercury.

These factors have their effects at the cellular level. A deficiency will almost always result in a harmful change in homeostasis, whether caused by internal or external influences. Too much toxicity also causes homeostatic imbalance, resulting in cellular malfunction. By removing negative health influences and providing adequate positive health influences, your body is better able to self-regulate and self-repair, maintaining homeostasis.