5 Real Physiological Causes of Depression

By Raluca Schachter

Contributing writer for Wake Up World

Depression is probably one of the most misunderstood and poorly treated health conditions in our modern era. But this, like any other negative symptom or condition, is based on a number of real causes, which can be systematically determined and solved.

Depression is yet another common result of poor brain function and its deterioration. From a neurological point of view, depression reduces the connections in the frontal lobe, the area in front of the brain, which gives us motivation and a sense of well-being. Many different things can cause this poor connection, including imbalances in brain chemicals or hormones.

For example, we know that men need sufficient testosterone and women need estrogen for proper frontal lobe function and a mere deficiency of these hormones can cause depression. Chemical mediators, called neurotransmitters, significantly influence the frontal lobe. If they are deficient or their pathways are not functioning properly, this can cause depression. These can’t be resolved with antidepressants because the real cause is not addressed.

Depression and the Gastrointestinal System

The relationship between the brain and the gastrointestinal system is today an interesting area of ??research. It appears that the gastrointestinal tract contains chemical messengers – peptides and hormones – that have a profound impact on brain health. Peptides in the intestine influence the immune system of the brain and the neurotransmitter pathways. Studies have linked intestinal peptides to depression, mood disorders, schizophrenia, Parkinson’s, memory loss.

There are multiple ways of communication from the gastrointestinal system to the brain and back. You may have noticed that a certain food significantly affects your mood. For example, have you ever eaten something that caused you bloating, stomach cramps, etc. and then became irritable and angry afterwards? Your mood changes have developed with digestive symptoms. This is just one example of how a chemical introduced into the gastrointestinal tract can immediately affect brain chemistry.

The researchers also found that the gut flora, the few kilograms of microorganisms we carry in the gut, affects the brain chemistry. Processed diets, stress, excess sugar and chemicals, genetically modified foods, repeated use of antibiotics and more cause imbalances in the gut flora, so pathogenic bacteria outweigh the beneficial ones.

It has also been shown that leaky gut syndrome plays an important role in severe depression, allowing pathogenic bacteria to enter the bloodstream. These bacteria carry lipopolysaccharides (LPS) in their membranes, large molecules that trigger inflammation. LPS swell the intestinal wall and once they reach the bloodstream, they cause inflammation throughout the body, which can change brain chemistry and cause depression.

This mechanism is called the “cytokine model of depression” because it is associated with inflammation, and not with neurotransmitter deficiencies. Leaky gut syndrome increases the production of inflammatory cytokines, which activate the immune system of the brain, creating inflammation and degeneration of the brain. This affects neuronal function and communication, which can lead to severe depression.

The Adrenal Glands and Depression

We, as humans, are not meant to be depressed, but our body has developed a kind of biochemical reflex, an automatic response to toxins, stress and inflammation that can cause depression. In other words, we are programmed to be depressed, because our body sacrifices the supply of tryptophan (an essential amino acid) when we are under stress of any form. Under stressful conditions, the body will be forced to lower the tryptophan level, so that our cells have a better chance of survival. Thus, our body is programmed to “steal” from the tryptophan needed for serotonin production. A low level of serotonin causes depression, among many other negative symptoms.

The physiological, mental and emotional stress in which most modern people live, triggers a strong and ancient reflex in our brain that causes the activation of the adrenal glands. If they are permanently activated, then they enter what is called the adrenal stress reaction. This reaction creates dramatic changes in cortisol, which affects all areas of our body, but especially our brain, energy and our state of mind. A high level of cortisol is a major cause of low serotonin and an important factor in “tryptophan theft.”

Glycemic Status and Depression

Most people know that glycemic problems such as diabetes involve a high level of insulin and blood glucose. But what is less well known is that people with glycemic problems often face hypoglycemia or low blood sugar. This actually lowers insulin and glucose, but raises another powerful hormone in the pancreas called glucagon. High glucagon levels can destroy our tryptophan intake and lead to decreased serotonin, depression and poor quality sleep.

Replenishing our body with tryptophan is essential. The body cannot produce tryptophan, which leads to situations where it is not sufficiently distributed where needed, forcing the body to steal tryptophan from neurotransmitters to make more NAD (one of the co-enzymes of vitamin B3). Stress, glycemic imbalances and inflammation decrease oxygen in cells, increasing the need for NAD, which comes only from tryptophan. Ultimately, the body “prefers” to increase the level of NAD, to survive and prevent cell destruction, rather than to make serotonin, sleep well and enjoy a good libido. The body never fails!

causes of depression

Nutritional Deficiencies and Depression

Amino acids

Amino acids are fragments of vital proteins used to build and repair tissues and contribute to the production of enzymes, hormones, bones, muscles and blood. Amino acids are also the “raw material” for mood stabilization and the production of neurotransmitters, which include serotonin, dopamine, GABA and endorphins.

Low levels of amino acids lead to low levels of neurotransmitters. It’s that simple!

The main reasons for the amino acid deficiencies are low protein consumption, poor digestion, and the use of antacid drugs (gastric acid is needed to break down the proteins and obtain the essential amino acids.)


Zinc has been named the “new antidepressant”. It is an essential cofactor in the conversion of amino acids for the production of important neurotransmitters in maintaining good mood – L-Tryptophan for serotonin and L-tyrosine for dopamine. Zinc helps regulate copper, which is an essential cofactor for dopamine production. At high levels, copper can cause depression, anxiety, panic disorder and agitation. Zinc is also essential for making digestive enzymes and hydrochloric acid, necessary for protein digestion.

Magnesium deficiency is well known to produce neuropathologies. Magnesium ions regulate the flow of calcium ions into the neural calcium channels, contributing to the regulation of neuronal nitric oxide production. In magnesium deficiency, neuronal requirements for magnesium may not be met, causing neuronal damage that can manifest as depression.

The brain and nerves desperately need iron. Without enough iron in the brain and nerves, problems arise with neurotransmitter signaling, with the formation of nerve isolation called myelin, and with the energy metabolism of the brain. Iron is essential for a number of enzymes involved in the synthesis of neurotransmitters, including tryptophan hydroxylase (serotonin) and tyrosine hydroxylase (norepinephrine). In addition, iron is linked to the activity of monoamine oxidase, an enzyme critical to the proper degradation rates of these neurotransmitters.


Vitamin B12 is essential for brain function. B12 supports myelin (which is involved in nerve management) and is a necessary cofactor in the methylation cycle. A low level of B12 can cause cognitive symptoms and mental imbalance, including depression, anxiety, fatigue and even psychosis.

Vitamin B6 is one of the most important vitamins for mental health due to its role as a cofactor in the production of neurotransmitters – serotonin, GABA and dopamine. A deficiency can lead to a wide variety of symptoms, including anxiety, depression, irritability, confusion, fatigue and exacerbation of PMS symptoms.

Vitamin D is a unique neurosteroid hormone that can play an important role in the development of depression. Vitamin D receptors are present on neurons and in many areas of the brain, which have been implicated in the pathophysiology of depression. Vitamin D is involved in many brain processes, including neuroimmunomodulation, neuroprotection, neuroplasticity and brain development.


Cholesterol is essential for maintaining good mental health. The brain is the highest cholesterol-rich organ in the body, and the brain’s lack of essential fatty acids and cholesterol can lead to health problems. Lower levels of cholesterol in the blood are associated with an increased risk of developing severe depression, as well as an increased risk of death from suicide.

Cholesterol is a critical precursor of many essential physiological molecules in the human body, which directly and indirectly affects our moods and optimal brain function. Some researchers believe that low cholesterol levels alter brain chemistry, suppressing serotonin production and / or availability. Cholesterol is essential for the synthesis of all steroid and sex hormones, including DHEA, testosterone and estrogen.

As you can see, the causes of depression are primarily physiological and can be solved for the most part by adopting the right diet and by solving the biochemical and metabolic imbalances. These, together with the multitude of therapies for good mental and emotional health, which are readily available, are practically the “treatment” for depression.

For specialized consultation for your health problems you can schedule an appointment here.


Originally published at metabolicenergy.net and reproduced here with permission.

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About the author:

Raluca Schachter is a dedicated Clinical Nutritionist / Natural Health Practitioner a.k.a “The Health Detective”. Raluca was able to naturally reverse chronic health conditions she was struggling with most of her life, and now uses her knowledge to help as many people as possible do the same. Her health programs and diet plans offer a very unique and comprehensive approach to health, where individual nutritional and biochemical requirements are firstly met using specific nutrients and foods that each metabolism thrives on. Raluca offers her services to international clientele and her practice is fully online based. You can connect with Raluca at www.metabolicenergy.net and https://www.facebook.com/raluca.schachter.metabolicenergy

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