Probiotics for Depression

Probiotics for depression are commanding the attention of researchers and a few mental health providers and for good reason. Psychobiotics, as they are called, are showing that mental health conditions may have roots in the gut.

Depression takes its toll on the affected person as well as on people around him/her. There has to be some light that makes it through the veil of darkness to give depressed people hope! Hope is being found through the actions of psychobiotics, probiotics shown to influence brain function.

Statistics for the US show that about 6.7% of adults in any given year are affected by depressed mental states. The median age for onset of major depressive disorder is 32 and more women are affected than men. However, about half of people diagnosed with depression are also diagnosed with an anxiety disorder.

There are are 3 main types of depressed states: major depressive disorder, persistent depressive disorder and bipolar disorder, which has a depressed component. The differences lie in the amount of time and severity of the disorder.

Major depressive disorder consists of at least 5 of the symptoms below for 2 weeks at levels so intense that they are disabling and interfere with work, study, eating and sleep.

Persistent depressive disorder is less intense than the major one, but it lasts for at least 2 years. Many of the same symptoms are present, just at less intense levels. These may be the people who see the glass as half-empty.

Bipolar disorder takes people from severe highs (mania) or mild highs (hypomania) to severe lows (depression). The length of time in each phase is variable.

Classic symptoms of this mood disorder from the Anxiety and Depression Association of America (www.adaa.org)are:

  • Persistent sad, anxious or "empty" mood
  • Feelings of hopelessness, pessimism
  • Feelings of guilt, worthlessness, helplessness
  • Loss of interest or pleasure in hobbies and activities, including sex
  • Decreased energy, fatigue, feeling "slowed down"
  • Difficulty concentrating, remembering, making decisions
  • Insomnia, early-morning awakening, or oversleeping
  • Low appetite and weight loss or overeating and weight gain
  • Thoughts of death or suicide, suicide attempts
  • Restlessness, irritability
  • Persistent physical symptoms that do not respond to treatment, such as headaches, digestive disorders and pain for which no other cause can be diagnosed.

Persons who are depressed often experience symptoms similar to those of an anxiety disorder, such as nervousness, irritability, and problems sleeping and concentrating. However, each disorder has its own root causes and its own emotional and behavioral symptoms and patterns.

If you think you are suffering from a severe and/or prolonged depressed mood, please seek appropriate help!

What About Probiotics for Depression and Gut Issues?

According to the Depression and Bipolar Support Alliance (www.dbsalliance.org) “Up to 80% of those treated for depressed states show an improvement in their symptoms generally within four to six weeks of beginning medication, psychotherapy, attending support groups or a combination of these treatments. (National Institute of Health, 1998)”

But what about probiotics for depression? What about fixing gut issues? This should be the first thing addressed!

Mental health does not occur in a vacuum apart from the rest of the body. The GI tract can affect the brain and the brain can affect the GI tract as I discuss in my book, Probiotics: How to Use Them to Your Advantage. If you have dysbiosis (unbalanced flora) or other gastrointestinal problems in your gut, it is quite possible that they are affecting your mood.

Here is just a sampling of what some psychiatrists have to say on the subject:

  • A clinical psychiatrist at University College Cork, Dr. Ted Dinan, minted the term psychobiotic because he knows that there is a gut-brain connection to moods and cognitive function. He is a strong believer in probiotics for depression.
  • An article in Clinical Psychopharmacology and Neuroscience 2015 by Drs. Alper Evrensel and Mehmet Emin Ceylan stated, "the microbiota has been suggested to be the key factor in the link between unhealthy diets and depression." Since diet affects depression and the gut microbiome, and probiotics can affect the gut microbiome, probiotics for depression and a healthy diet may be helpful.
  • The recently released book, A Mind of Your Own, by Dr. Kelly Brogan, board-certified in psychiatry, psychosomatic medicine and integrative holistic medicine, delves deeper into the condition of depression and states that "not a single study has proven that depression is caused by a chemical imbalance in the brain." Her book outlines her approach to treating this condition and is a worthwhile read.

What Do Scientific Studies Show About the Potential of Probiotics for Depression?

A 2015 article in the journal “Brain, Behavior and Immunity” looked at an established marker of vulnerability to depressed mental states: heightened cognitive reactivity.

Cognitive reactivity is the activation of dysfunctional patterns of thinking triggered by subtle changes in mood. For example, let’s say something does not go the way you had planned. You are naturally disappointed. How you handle that disappointment sheds light on whether you have dysfunctional patterns of thinking or not.

The dysfunctional patterns of thinking involve one or more of the following:

Ruminative thinking = thinking over and over about the causes and consequences of your predicament. Are you dwelling on what happened?

Aggressive thinking = thinking about hurting yourself or others. Are you so disappointed that you want to punish someone or something?

Hopelessness = thinking that the consequences of what happened will go on and on

Suicidal thinking = thinking that there is absolutely no way for you to recover from what happened and it would be better if you were not around

It is normal to think about how something happened to you, what it has done to you and how you are going to learn from that experience and try to prevent it from happening again. It is when that kind of thinking is repeated over and over and ends up leading to depression that it is a problem.

Those dysfunctional patterns of thinking are assumed to arise during low mood from negative beliefs that you already embrace, but normally suppress. If you cannot ‘bounce back’, then how strongly your dysfunctional thinking becomes seems to determine if your sad mood will be temporary or will be ongoing. The ongoing dysfunctional thinking increases your risk of developing clinical depression.

In the journal article, the researchers used the Leiden Index of Depression Sensitivity Scale-revised, a questionnaire that aims to measure cognitive reactivity independently from a mood induction procedure, for the pre- and post-intervention assessment of the effect of a probiotic formula on depressed individuals.

Researchers gave a multispecies probiotic called “Ecologic Barrier“ (Winclove probiotics, which is now available in my online dispensary as Klaire Target gb-X) for 4 weeks to 20 non-depressed individuals and placebo to 20 control individuals. All individuals were non-smoking young adults with no reported heart, kidney or liver conditions, no prescribed medication or drug use, no use of more than 3-5 alcoholic drinks per week and no allergies or intolerances to lactose or gluten. Additionally, the participants had no psychiatric or neurological disorders, no personal or family history of depressed states or migraine, and they were assessed for depressed states and anxiety with Beck Inventories prior to intervention.

The probiotic supplement contained: 5 billion CFU per sachet (one per day) of a mix of:

  • Bifidobacterium bifidum W23
  • Bifidobacterium lactis W52
  • Lactobacillus acidophilus W37
  • Lactobacillus brevis W63
  • Lactobacillus casei W56
  • Lactobacillus salivarius W24 
  • Lactococcus lactis W19 and W58.

This was a triple-blind, placebo-controlled, randomized, pre- and post-intervention assessment test. “Triple blind” means that neither the researchers, nor the participants, nor the evaluators of the Leiden index knew who received the active probiotic or the placebo.

Researchers were looking at the four patterns of dysfunctional thinking listed above and found that the two behaviors that were significantly helped by the probiotic formula were rumination and aggressive thoughts.

So this probiotic supplement significantly reduced negative thoughts associated with depressed mood! Find this supplement as Klaire Target gb-X in my dispensary.

Other Studies about Probiotics for Depression

Two other probiotics, Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 (in Probio’Stick and also in LifeExtension Florassist Mood from my online dispensary) have been shown efficacious as probiotics for depression. Taken together for 30 days they decreased the total scores on an anxiety, depressed states and anger/hostility symptoms checklist for hospitalized patients.

Three strains of probiotics, Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium bifidum taken together as probiotics for depression in a randomized, double-blind, placebo-controlled trial in 40 patients with major depressive disorder for 8 weeks showed significantly decreased Beck Depression Inventory total scores.

In a randomized, double-blind, placebo-controlled pilot study of 44 adults with IBS and diarrhea or a diarrhea/constipation-stool pattern and mild to moderate anxiety and/or depression, Bifidobacterium longum NCC3001 showed benefit as probiotics for depression for reducing depression (but not anxiety scores) and increasing quality of life in patients with IBS. This probiotic was shown to act on the brain limbic system and reduce responses to negative emotional stimuli, meaning that it helped to blunt the negative emotional responses that seem to dominate during depression.

There have been many animal studies as well. In one, rats with anxiety and depressed mental biochemical changes from chronic restraint stress, Lactobacillus helveticus NS8 showed a benefit similar to and better than that of citalopram (prescription medication, selective serotonin reuptake inhibitor [SSRI] Celexa).

These studies show that:

  • There isn’t only one type of microbe that can help with depressed states
  • That sometimes a single probiotic can help, and other times, multiple species of probiotics can help
  • Probiotics for depression, psychobiotics, may be part of the light to help end the darkness of depression!

What Is Recommended for a Depressed Person?

First and foremost, I am not a psychiatrist, so I am not qualified to diagnose, prescribe, treat or cure any mental disease. Nor can I possibly give general recommendations on something as serious as depression on a website. You must seek professional, qualified help if you feel you are depressed.

However, I do encourage you to improve your diet and lifestyle and to try to improve any leaky gut, food sensitivities and dysbiosis to reduce the chances that gut dysfunction is playing a role in your mood disorder. Probiotics for depression are an attractive way to improve your mental health as well as your overall health without the side effects of conventional medications. Nutrition therapy can help and I would be happy to work with your physician with your consent. Please DO NOT stop taking medications without approval from your doctor!


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