Why depression

You can buy boxes that emit the proper light intensity 10, lux with a minimal amount of ultraviolet light without a prescription, but it is best to work with a professional who can monitor your response. There are few side effects to light therapy, but you should be aware of the following potential problems:. Certain medical problems are linked to lasting, significant mood disturbances.

Among the best-known culprits are two thyroid hormone imbalances. An excess of thyroid hormone hyperthyroidism can trigger manic symptoms. On the other hand, hypothyroidism, a condition in which your body produces too little thyroid hormone, often leads to exhaustion and depression. Heart disease has also been linked to depression, with up to half of heart attack survivors reporting feeling blue and many having significant depression. Depression can spell trouble for heart patients: it's been linked with slower recovery, future cardiovascular trouble, and a higher risk of dying within about six months.

Although doctors have hesitated to give heart patients older depression medications called tricyclic antidepressants because of their impact on heart rhythms, selective serotonin reuptake inhibitors seem safe for people with heart conditions.

The following medical conditions have also been associated with depression and other mood disorders:. When considering the connection between health problems and depression, an important question to address is which came first, the medical condition or the mood changes.

There is no doubt that the stress of having certain illnesses can trigger depression. In other cases, depression precedes the medical illness and may even contribute to it.

To find out whether the mood changes occurred on their own or as a result of the medical illness, a doctor carefully considers a person's medical history and the results of a physical exam. If depression or mania springs from an underlying medical problem, the mood changes should disappear after the medical condition is treated.

If you have hypothyroidism, for example, lethargy and depression often lift once treatment regulates the level of thyroid hormone in your blood. In many cases, however, the depression is an independent problem, which means that in order to be successful, treatment must address depression directly. Sometimes, symptoms of depression or mania are a side effect of certain drugs, such as steroids or blood pressure medication.

Be sure to tell your doctor or therapist what medications you take and when your symptoms began. A professional can help sort out whether a new medication, a change in dosage, or interactions with other drugs or substances might be affecting your mood. Keep in mind the following regarding drugs that may affect depression and mood:. Reading Understanding Depression and sharing it with those closest to you might help improve your life — or the life of someone close to you!

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Recent Blog Articles. Cancer survivors' sleep is affected long after treatment. What to do when elective surgery is postponed. What happened to trusting medical experts? Stuttering in children: How parents can help. Evoking calm: Practicing mindfulness in daily life helps. Finding balance: 3 simple exercises to steady your steps. What causes depression? June 24, Onset of depression more complex than a brain chemical imbalance It's often said that depression results from a chemical imbalance, but that figure of speech doesn't capture how complex the disease is.

The brain's impact on depression Popular lore has it that emotions reside in the heart. Regions that affect mood Increasingly sophisticated forms of brain imaging — such as positron emission tomography PET , single-photon emission computed tomography SPECT , and functional magnetic resonance imaging fMRI — permit a much closer look at the working brain than was possible in the past.

Figure 1: Areas of the brain affected by depression Amygdala: The amygdala is part of the limbic system, a group of structures deep in the brain that's associated with emotions such as anger, pleasure, sorrow, fear, and sexual arousal. Nerve cell communication The ultimate goal in treating the biology of depression is to improve the brain's ability to regulate mood.

Here is a description of a few believed to play a role in depression: Acetylcholine enhances memory and is involved in learning and recall. Serotonin helps regulate sleep, appetite, and mood and inhibits pain. Research supports the idea that some depressed people have reduced serotonin transmission.

Low levels of a serotonin byproduct have been linked to a higher risk for suicide. Norepinephrine constricts blood vessels, raising blood pressure. It may trigger anxiety and be involved in some types of depression. It also seems to help determine motivation and reward. Dopamine is essential to movement. It also influences motivation and plays a role in how a person perceives reality.

Problems in dopamine transmission have been associated with psychosis, a severe form of distorted thinking characterized by hallucinations or delusions. It's also involved in the brain's reward system, so it is thought to play a role in substance abuse. Glutamate is a small molecule believed to act as an excitatory neurotransmitter and to play a role in bipolar disorder and schizophrenia. Lithium carbonate, a well-known mood stabilizer used to treat bipolar disorder, helps prevent damage to neurons in the brains of rats exposed to high levels of glutamate.

Other animal research suggests that lithium might stabilize glutamate reuptake, a mechanism that may explain how the drug smooths out the highs of mania and the lows of depression in the long term. Gamma-aminobutyric acid GABA is an amino acid that researchers believe acts as an inhibitory neurotransmitter.

It is thought to help quell anxiety. Figure 2: How neurons communicate An electrical signal travels down the axon. Chemical neurotransmitter molecules are released. The neurotransmitter molecules bind to receptor sites. The signal is picked up by the second neuron and is either passed along or halted.

The signal is also picked up by the first neuron, causing reuptake, the process by which the cell that released the neurotransmitter takes back some of the remaining molecules. Genes' effect on mood and depression Every part of your body, including your brain, is controlled by genes. Temperament shapes behavior Genetics provides one perspective on how resilient you are in the face of difficult life events. Stressful life events At some point, nearly everyone encounters stressful life events: the death of a loved one, the loss of a job, an illness, or a relationship spiraling downward.

How stress affects the body Stress can be defined as an automatic physical response to any stimulus that requires you to adjust to change. Early losses and trauma Certain events can have lasting physical, as well as emotional, consequences. Seasonal affective disorder: When winter brings the blues Many people feel sad when summer wanes, but some actually develop depression with the season's change.

There are few side effects to light therapy, but you should be aware of the following potential problems: Mild anxiety, jitteriness, headaches, early awakening, or eyestrain can occur. There is evidence that light therapy can trigger a manic episode in people who are vulnerable.

While there is no proof that light therapy can aggravate an eye problem, you should still discuss any eye disease with your doctor before starting light therapy. Likewise, since rashes can result, let your doctor know about any skin conditions. Some drugs or herbs for example, St. John's wort can make you sensitive to light.

If light therapy isn't helpful, antidepressants may offer relief. Medical problems Certain medical problems are linked to lasting, significant mood disturbances. The following medical conditions have also been associated with depression and other mood disorders: degenerative neurological conditions, such as multiple sclerosis, Parkinson's disease, Alzheimer's disease, and Huntington's disease stroke some nutritional deficiencies, such as a lack of vitamin B12 other endocrine disorders, such as problems with the parathyroid or adrenal glands that cause them to produce too little or too much of particular hormones certain immune system diseases, such as lupus some viruses and other infections, such as mononucleosis, hepatitis, and HIV cancer erectile dysfunction in men.

Depression medications Sometimes, symptoms of depression or mania are a side effect of certain drugs, such as steroids or blood pressure medication. Keep in mind the following regarding drugs that may affect depression and mood: Researchers disagree about whether a few of these drugs — such as birth control pills or propranolol — affect mood enough to be a significant factor.

Most people who take the medications listed will not experience mood changes, although having a family or personal history of depression may make you more vulnerable to such a change. Some of the drugs cause symptoms like malaise a general feeling of being ill or uncomfortable or appetite loss that may be mistaken for depression. Even if you are taking one of these drugs, your depression may spring from other sources. Exposure to light can help improve mood for people affected by SAD. The death of a family member, friend, or pet sometimes goes beyond normal grief and leads to depression.

Other difficult life events — such as when parents divorce , separate, or remarry — can trigger depression. Whether or not difficult life situations lead to depression can depend a lot on how well a person is able to cope, stay positive, and receive support.

For some people, a negative, stressful, or unhappy family atmosphere can lead to depression. Other high-stress living situations — such as poverty, homelessness, or violence — can contribute, too. Dealing with bullying , harassment, or peer pressure leaves some people feeling isolated, victimized, or insecure. Situations like these don't necessarily lead to depression, but facing them without relief or support can make it easier to become depressed. Life is full of ups and downs.

Stress, hassles, and setbacks happen but hopefully not too often. How we react to life's struggles matters a lot. A person's outlook can contribute to depression — or it can help guard against it.

Research shows that a positive outlook acts as a protection against depression, even for people who have the genes, brain chemistry, or life situations that put them at risk for developing it.

The opposite is also true: People who tend to think more negatively may be more at risk for developing depression. We can't control our genes, brain chemistry, or some of the other things that contribute to depression.

But we do have control over how we see situations and how we cope. Making an effort to think positively — like believing there's a way around any problem — helps ward off depression.

So does developing coping skills and a support system of positive relationships. These things help build resilience the quality that helps people bounce back and do well, even in difficult situations. Here are three ways to build resilience:. Being positive and resilient isn't a magic shield that automatically protects us from depression. But these qualities can help offset the other factors that might lead to trouble.

The stress of having a chronic illness may trigger an episode of major depression. In addition, certain illnesses, such as thyroid disorders, Addison's disease, and liver disease, can cause depression symptoms.

It has been widely documented that women experience major depression about twice as often as men. Because of the incidence of depressive disorders peaks during women's reproductive years, it is believed that hormonal risk factors may be at play. Women are especially prone to depressive disorders during times when their hormones are in flux, such as around the time of their menstrual period , pregnancy, childbirth, and perimenopause. Hormone fluctuations caused by childbirth and thyroid conditions can also contribute to depression.

Postpartum depression may occur after a woman has given birth and is believed to result from the rapid hormonal changes that take place immediately after giving birth. In addition, a woman's depression risk declines after she goes through menopause. A family history of depression is another significant risk factor. You are more likely to experience symptoms of depression if others in your family also have depression or another type of mood disorder. Twin, adoption, and family studies have linked depression to genetics.

While studies suggest that there is a strong genetic component, researchers are not yet certain about all the genetic risk factors for depression. Researchers have found that having a parent and grandparent with depression doubles the risk of depression. It is still unclear exactly which genes play a role in depression and other mood disorders, but researchers do know that there are many different genes that can play a role.

By better understanding how they function, gene researchers hope to be able to create more effective treatments. It is important to remember that no single cause of depression acts in isolation. Genetic factors may be a major risk factor, but scientists also believe that genes and the environment interact to control exactly how these genes are expressed.

There are also a number of lifestyle factors that can play a role in causing depression. While many of the risk factors for depression, such as your sex or your family history, cannot be changed, people have much more personal control over lifestyle factors.

One type of depression, called seasonal affective disorder officially known as major depressive disorder with seasonal pattern is believed to be caused by a disturbance in the normal circadian rhythm of the body. Light entering the eye influences this rhythm, and, during the shorter days of winter, when people may spend limited time outdoors, this rhythm may become disrupted. People who reside in colder climates where there are short, dark days may be at the highest risk. In addition to disruptions in circadian rhythm, reduced sunlight can also lead to a drop in serotonin levels in the brain, which may influence mood.

Seasonal changes can also alter melatonin levels in the body, which can disrupt sleep and contribute to mood changes. While you cannot control seasonal shifts, there are steps you can take to minimize the effect these changes have on your mental health. A poor diet can contribute to depression in several ways. A variety of vitamin and mineral deficiencies are known to cause symptoms of depression.

Some studies have found that diets either low in omega-3 fatty acids or with an imbalanced ratio of omega-6 to omega-3 are associated with increased rates of depression. In addition, diets high in sugar have been associated with depression. Stressful life events, which overwhelm a person's ability to cope, can also be a cause of depression. Researchers suspect high levels of the hormone cortisol, which are secreted during periods of stress, may affect the neurotransmitter serotonin and contribute to depression.

Following the loss of a loved one, grieving individuals experience many of the same symptoms of depression. Trouble sleeping, poor appetite, and a loss of pleasure or interest in activities are a normal response to loss.

The symptoms of grief are expected to subside over time. But when symptoms get worse, grief may turn into depression. Drugs and alcohol can contribute to depressive disorders. Some drugs that have been found to be associated with depression include anticonvulsants, statins, stimulants, benzodiazepines, corticosteroids, and beta-blockers.

It's important to review any medications that you've been prescribed and to speak with your physician if you are feeling depressed. No matter the cause, there are effective treatments available.