Vegetarian eating and depression: what the data show
One meta-analysis finds 53 percent more depression risk, another 26 percent less. Both numbers can be right. How that fits together, and what gene variants, grown cuisines and study design have to do with it.
More articles from the nutrition cluster
That eating vegetarian is the healthier choice counts as self-evident. For many people it can be exactly that. What gives me pause is not the way of eating. It is how unquestioned we leave it, even though the data on mental health openly contradict each other.
You are sitting on the sofa in the evening and the day feels like it happened through a layer of cotton wool. Not bad. Just flat.
You sleep decently, you move, you eat more consciously than most people you know. No meat for a year and a half, for good reasons. And still there is this question you barely dare to ask out loud. Could that be connected?
In online forums this question appears in a hundred variants. Vegetarian since recently, tired ever since. Took iron and B12, no improvement. I hear something similar in my consultations.
I want to take this question seriously and answer it honestly, even though the honest answer is less comfortable than any headline.
What to expect here
- Why two meta-analyses deliver opposite numbers
- What the Europe versus Asia subgroup shows, and what it does not
- Why cause and effect could run the other way here
- What FADS gene variants have to do with plant fatty acids
- Why a grown cuisine is not the same as meat left out
- Four levers your mood can hang on
- Which values you may know before you take anything
- Twelve questions I get asked about this most often
Why this question is so hard to ask
Eating stopped being only eating a long time ago. It has become a stance, often an identity.
That is exactly why the question about your own mood is so uncomfortable. It feels like a betrayal of a decision you made for good reasons. So people ask it at night on the internet, anonymously.
Nowhere in this text do I advise you to stop being vegetarian. I want to show you how unclear the study landscape is, and which questions are worth asking if you do not feel the way you had hoped.
The question is not: are you eating wrong? It is: does your way of eating come with the knowledge it needs?
That is the difference between an instrument and the lessons that go with it.
And now you know why this text starts with a contradiction and not with a number.
Two numbers that contradict each other, and both can be right
Maybe you have seen one of the headlines. Both exist, both come from serious journals, and they say the opposite of each other.
Depression risk among vegetarians, pooled from nine mostly cross-sectional effect sizes.
Depression risk on meat-free eating, pooled from twenty longitudinal studies.
An Iranian research group around Siavash Fazelian searched five databases for observational studies on depression among vegetarians. Across nine effect sizes the risk was 53 percent higher, with an odds ratio of 1.53 and a confidence interval of 1.14 to 2.07. In the comparison of mean depression scores across sixteen studies, however, the difference disappeared entirely.
For you that means: the number exists and is still not a verdict. The authors themselves do not call their findings robust.
Fazelian S et al. Nutrition Reviews. 2022. DOI: 10.1093/nutrit/nuab013A Spanish group around Andrea Luque-Martínez collected only longitudinal studies in 2025, that is, work in which eating was recorded before depression appeared. Across twenty such studies, meat-free eating was linked to a lower risk, hazard ratio 0.74 with a confidence interval of 0.59 to 0.89.
For you that means: as soon as you respect the time axis, the sign flips. That is not a detail, that is the heart of the matter.
Luque-Martínez A et al. Nutrients. 2025;17(5):811. DOI: 10.3390/nu17050811How can the same topic come out so differently? Imagine two photographers. One takes a group photo in the emergency department and counts who looks ill. The other follows those same people for two years and counts who becomes ill. Both photograph honestly, they just do not photograph the same thing.
Cross-sectional studies record eating and mood in the same moment. Anyone who changes their food during a hard phase turns up there as a vegetarian with depression. About cause and effect that says nothing.
A group at King's College London around Rishika Jain assessed 23 studies to PRISMA standard, with three independent raters. Of 25 study results, eleven, that is 44 percent, showed higher depression rates, seven showed more favourable values and seven showed no association at all. Only four studies were rated as good, nineteen as moderate.
For you that means: the literature is not thin, it is divided. Anyone who gives you an unambiguous answer here is telling you only half the story.
Jain R et al. Nutrition Bulletin. 2022;47(1):27-49. DOI: 10.1111/nbu.12540There are more numbers. A meta-analysis from 2021 found an odds ratio of 2.14 and lower anxiety scores at the same time. Another found 1.02, no association at all. An umbrella review of nine systematic reviews concluded in 2026 that four of them reported an increased risk and five found contradictory associations or none.
A contradiction between studies is not a scandal. It is usually a hint that the question was asked too coarsely.
Vegetarian is not a state. It is a label on very different plates, chosen for very different reasons.
And now you know why the interesting question is not who is right.
Europe yes, Asia no: the finding at the centre of this
Maybe you know someone from a South Indian family. Vegetarian for generations, and nobody would think of calling that a health risk.
This is exactly where the study landscape gets interesting. The 2022 meta-analysis also split its data by country of origin. And something showed up there that almost nobody mentions in the popular coverage.
| Subgroup | Effect estimate | What it says there |
|---|---|---|
| Studies from Europe and the USA | OR 1.45 | confidence interval 1.06 to 1.98, heterogeneity 73.2 percent |
| Studies from Asian countries | no association | the effect disappears |
| Semi-vegetarians | OR 1.86 | the most strongly associated group |
| Lacto-ovo vegetarians | no association | although this is the classic form |
| Mean depression scores | SMD 0.10 | across sixteen studies, no difference |
Read the row on semi-vegetarians once more. Of all groups, the people who still eat meat occasionally are the most strongly associated, and the classic lacto-ovo vegetarians not at all. That fits a simple deficiency model badly.
A research group around Yu-Chih Shen followed 10,577 people in the Taiwanese Tzu Chi cohort for around nine years and recorded new depression not by questionnaire but through medical diagnoses in the national health insurance data. Incidence was 2.37 among vegetarians and 3.21 among non-vegetarians per 10,000 person years, with an adjusted hazard ratio of 0.70.
For you that means: in a population with a long vegetarian tradition the sign flips, prospectively and with hard diagnostic data.
Shen YC et al. Nutrients. 2021;13(4):1059. DOI: 10.3390/nu13041059The Taiwan cohort consists of members of a Buddhist foundation. Strong religious and social belonging is on its own linked to a lower depression risk. So the finding cannot be attributed to food alone.
And the regional difference itself comes from exactly one meta-analysis. Another research group with 13 studies and 49,889 people explicitly names as a limitation that the geographical spread of study sites was narrow. A subgroup analysis is a hint, not evidence in its own right.
Still it is worth following the hint. If an association shows up in one world region and not in another, it is probably not the tofu.
Two explanations are plausible. One is biological: people differ in how well they rebuild plant fatty acids. The other is cultural: a cuisine that has managed without meat for centuries looks different from one that has just had the meat taken out of it. We will follow both. But first comes the part that could put both into perspective.
And now you know why a regional difference is interesting without being an answer.
Before we explain biology: maybe the cause runs the other way
In every conversation about this topic there is a moment when it tips. Someone says: so a vegetarian diet does make you depressed after all. And everyone nods. That is the moment I raise my hand.
Because there is a second explanation that fits all the numbers just as well: people who are not doing well mentally change their eating more often. Not the other way round.
Johannes Michalak and colleagues analysed a representative German sample of 4,116 people, with a sociodemographically matched control group. Vegetarians more often had depressive, anxiety and somatoform disorders. Then they set the age at the dietary change against the age at onset of the disorder: the change followed the disorder.
For you that means: the one German dataset that checked the order finds it the other way round. The authors write explicitly that there is no evidence for a causal role.
Michalak J et al. Int J Behav Nutr Phys Act. 2012;9:67. DOI: 10.1186/1479-5868-9-67Joane Matta and colleagues examined 90,380 people in the French Constances cohort and tested the exclusion of any food group at all. Leaving out meat was linked to an odds ratio of 1.37 for depressive symptoms, fish to 1.40, vegetables to 1.71. And the odds ratio rose stepwise with the number of groups dropped.
For you that means: someone who drops vegetables carries a higher associated risk here than someone who drops meat. The marker is the leaving out itself.
Matta J et al. Nutrients. 2018;10(11):1695. DOI: 10.3390/nu10111695“Reverse causation cannot be ruled out.”
Hibbeln JR et al., ALSPAC cohort with 9,668 men, Journal of Affective Disorders 2018That sentence comes from a paper that itself found a clear association: 350 vegetarian men with depression scores 0.96 points higher on average and an odds ratio of 1.67 after adjustment. And still the researchers write that a reversed cause cannot be ruled out. This caution is not politeness. It is necessary.
The part I want to phrase especially carefully
In every larger group of vegetarians there are also people for whom food is currently a place of control. That is not an insinuation, it is a well documented observation.
In a comparison of three groups, the share of those who had ever lived vegetarian rose from 6.8 percent without an eating disorder to 17.6 percent with disordered eating and 34.8 percent in inpatient treatment. And in a case control study with 160 women, the share of current vegetarians fell with the degree of recovery from 33 to 13 to 5 percent.
Distributions like these skew every statistic about vegetarians. About you as an individual reader they say nothing. If you recognise yourself here, the guide on eating disorders and the interplay of body and mind offers a calmer framing.
Ulka Agarwal and colleagues guided one of two groups at ten sites of a US insurer through eighteen weeks of plant-based eating, 292 people with overweight or type 2 diabetes in total. In the intention-to-treat analysis, depression, anxiety and fatigue improved significantly more in this group. The authors describe their own design as quasi-experimental, with randomisation at site level and without blinding.
For you that means: if you have people eat plant-based instead of asking who already eats that way, the result turns around.
Agarwal U et al. Am J Health Promot. 2015;29(4):245-254. DOI: 10.4278/ajhp.130218-QUAN-72When someone changes their food during a hard phase, that is not a mistake. It is often an attempt at self-care.
The statistics then look as though the food had triggered something. In fact they are seeing the moment when someone began to care for themselves.
And now you know why I explain the biology only after this. It is interesting, but not the only explanation.
Why your metabolism may translate differently
Now to the biology. And first the sentence that stands over this section: this is about how often gene variants occur and about grown food traditions. It is not about people being better or worse.
Plant foods carry omega-3 as alpha-linolenic acid, ALA for short. Flaxseed, walnuts, chia. But your brain and your cell membranes need the long-chain forms EPA and DHA. Your body can rebuild ALA, and the blueprint for the enzymes sits in the genes FADS1 and FADS2.
Imagine two translators. Both get the same text. One works fluently, the other looks up every second word. Both are good translators, they just have different amounts of practice in this language.
Kumar Kothapalli and colleagues determined the frequency of a 22 base pair insertion in the FADS2 gene in a largely vegetarian Indian population, in a US population and in the data of the 1000 Genomes Project. The efficient insertion variant was found in 70 percent of South Asian and in 17 percent of European genomes. In its carriers, arachidonic acid in plasma phospholipid was eight percent higher, and the difference between product and precursor 31 percent.
For you that means: how well someone rebuilds plant fatty acid precursors is partly written into the genes, and these variants differ in frequency by region.
Kothapalli KSD et al. Mol Biol Evol. 2016;33(7):1726-1739. DOI: 10.1093/molbev/msw049Frequency of the efficient FADS2 variant by 1000 Genomes data
These are frequencies in population groups, not statements about individual people. Both variants exist in each of these groups. Your own genotype cannot be read off your ancestry.
And the difference does not stop at continental borders. A European paper with five cohorts from Sweden, Scotland, Italy, Croatia and the Netherlands showed that people today carry two common FADS haplotypes, defined by 28 linked gene variants. In their conversion performance they differ, as the authors write, dramatically.
So the more honest question is not whether Europeans are different from South Asians, but: which variant do you carry? More in the guide on genes, ancestry and metabolism.
On top of that comes a second factor. The conversion from the plant precursors is, as one review calls it, highly inefficient anyway, and omega-6 and omega-3 share the same enzymes. A diet with a lot of sunflower, safflower and soybean oil sends a great deal of omega-6 to the same switch. Details in the guide on ALA, EPA and DHA.
The work by Kothapalli measures arachidonic acid, so the omega-6 side. That a poorer conversion also affects EPA, DHA and through them mood is mechanistically plausible, because the same enzymes are involved. Nobody has measured that as a continuous chain. It is a hypothesis, not a finding.
Gene variants are not a diagnosis and not a verdict. They only say how much support a metabolic pathway needs.
One translator needs no dictionary. The other works just as well with one. He only needs one.
And now you know why the same food can land differently in two people, without either of them doing anything wrong.
A grown cuisine is not the same as meat left out
Think of a South Indian plate. Dal from lentils, rice, fermented batter for idli or dosa, yoghurt, ghee, turmeric, sesame.
And of a typical European switch. The schnitzel goes out, the substitute product comes in, otherwise the plate stays the same. These are not two variants of the same way of eating, they are two different things with the same label.
South Asian cuisine grew over centuries without meat, with legumes as the protein source, dairy for B12 and fat, fermentation and soaking against phytate. Nobody planned this. It grew. A European vegetarian diet, by contrast, begins with a subtraction, and the gap is often filled with whatever is quickest.
Hanzhang Wu and colleagues analysed 180,532 people in the UK Biobank and built three indices from 17 food groups: how plant-based overall, how healthy plant-based, how unhealthy plant-based. The overall index said practically nothing about depression. Only the split by quality separated cleanly: healthy plant-based food came in at a hazard ratio of 0.92, unhealthy at 1.15, and for dementia even 0.82 against 1.29.
For you that means: eating plant-based is not an answer, it is a question. It hangs on what you replace the meat with.
Wu H et al. Age Ageing. 2023;52(5):afad070. DOI: 10.1093/ageing/afad070A Spanish group around Bruno Bizzozero-Peroni pooled 23 studies with 709,703 people and likewise split by quality. A healthy plant-based diet was associated cross-sectionally with an odds ratio of 0.74 for depression, in cohort data with 0.77. An unhealthy plant-based diet was linked to more anxiety and more depression.
For you that means: this dividing line is among the best supported statements in the whole field, more solid than any number attached to the label.
Bizzozero-Peroni B et al. Nutrition Reviews. 2025;83(12):2282-2295. DOI: 10.1093/nutrit/nuaf080What counts as unhealthy plant-based food? White flour, sugar, sweetened drinks, sweets, heavily processed products. All plant-based, all vegetarian, and unfavourable in these data. A meta-analysis on ultra-processed foods found a relative risk of 1.20 for depression at the highest intake, though from only two cohorts.
And one detail from the Constances data fits exactly here: the link with depressive symptoms was especially pronounced at low legume intake.
Legumes are the point where the two plates differ. They deliver protein, fibre, iron, zinc and folate. Soaking, sprouting and fermenting can additionally lower the phytate that binds iron and zinc.
The question is not the missing meat, it is what stands in its place. A grown cuisine has answered that over generations. A substitute product answers the shape.
That is not a criticism of going without, it is an observation about craft. More on this in the guide on unprocessed food and satiety and in the piece on the calorie myth.
Vegetarian is not a way of eating. It is an omission, and what becomes of it is decided only afterwards. So the interesting question is less what you leave out than what you learned in exchange.
And now you know why two people with the same label can be eating two different diets.
The four levers your mood can hang on
Do you know that feeling when you know something is missing but cannot say what? With nutrients that is the normal case. You do not notice a gap, only that less is possible than before.
The whole nutrient story is in the guide on vegan eating, opportunities and limits. Here it is only about the four axes with a documented link to mood or performance.
EPA and DHA
A scoping review of thirteen randomised trials compared plant omega-3 sources by the omega-3 index, that is EPA plus DHA in the red blood cell. High-dose flaxseed oil and echium oil did not raise it, in individual trials it even fell. Microalgae oil raised it in every trial.
In a meta-analysis of 26 double-blind trials with 2,160 people, EPA-weighted preparations in particular showed an effect on depressive symptoms, with a mean difference of 0.50 for pure EPA. Pure DHA formulas did not show this. In a matched study of 47 people, the long-chain omega-3 fractions were also significantly lower in vegans.
Iron and ferritin
A meta-analysis of 24 cross-sectional studies found serum ferritin 29.71 micrograms per litre lower in adult vegetarians, and 61.88 lower in men.
To stay fair: high iron stores are a risk too, and the authors recommend checks for both groups. What a low store can mean for the mind is in the guide on iron deficiency and the mind and on iron deficiency on vegan and vegetarian diets.
Vitamin B12 and homocysteine
A systematic review of 18 studies determined B12 status through functional markers such as methylmalonic acid or holotranscobalamin. Deficiency rates were 62 percent in pregnant women, between 25 and almost 86 percent in children, and between 21 and 41 percent in adolescents, independent of age, place of residence and type of vegetarian diet.
A review found mean homocysteine values above 10 micromol per litre in 32 of 34 reports. This is where a functional gap becomes visible before the blood count reacts.
Creatine and zinc
The most elegant finding comes from a randomised, double-blind trial with 128 young women. Five days of creatine or placebo, then cognitive tests. In the vegetarian women memory performance improved, in the meat eaters it did not. A review of six randomised trials with 281 people in total found the same pattern, though limited to narrowly defined memory tasks.
With zinc the picture is weaker. A meta-analysis of 17 studies found zinc values 1.85 micromol per litre lower in people with depression, but in people with depression in general and not in vegetarians. I put this side by side, explicitly not as a chain.
The thread behind all four points is the same: not swallowing capsules as a precaution, but knowing your own status before you change anything.
Values that allow a proper reading
- Ferritin together with CRP and a blood count. Inflammation can lift ferritin and hide an empty store.
- Holotranscobalamin or methylmalonic acid instead of serum B12 alone, plus homocysteine as a functional cross-check.
- Zinc and vitamin D, often tight on plant-based food and at northern latitudes.
- Omega-3 index from the red cell membrane. How to read the value is in the guide on the omega-3 index.
- Thyroid values, because tiredness and low drive can come from there as well.
Which values make sense for you belongs in a medical conversation. A single number rarely makes a picture.
Measuring is not the opposite of trusting your own body. It is the condition for it. Whoever guesses often takes the wrong thing.
And now you know why iron and B12 alone are often not enough.
What this means in practice, without talking you out of your food
Maybe while reading you thought: is he about to tell me to eat meat again? No. That is not what I am saying.
By the longitudinal data, a well run plant-forward diet looks rather protective. The most solid statement is not the number attached to the label, it is the dividing line between good and poor plant-based food. And that line runs through every way of eating, including the ones with meat.
What I would suggest are four directions. No recipes, no dosages.
The first three follow directly from the studies above. The fourth is what I observe in my consultations, and explicitly not a statement from a study.
Four directions that follow from the data
- Know your status instead of guessing. A blood draw before the first supplement can save you months.
- Legumes before substitute products. Lentils, chickpeas, beans, ideally soaked or fermented. This is exactly the group that was missing where the association was clearest.
- With omega-3, check the source. Flaxseed oil delivers the precursor, not the end product. At a low index, microalgae oil is an option by the studies available. More in the guide on omega-3 from plants, animals or algae.
- Take mood seriously as a measurement. If your drive has been flat for months, that is a finding and not a question of character.
And one more thing. If you do not feel well on the way you eat, you do not have to give up your values. It only means that something may be adjusted.
If you do not want to sort this out on your own: below this article you will find the option to book an appointment.
If you eat vegetarian, then eat vegetarian. And while you do, pay attention to your markers and your mood, as attentively as you would for someone you love.
And now you know why the answer to the question at the start is neither yes nor no. It depends, and you can find out on what.
Frequently asked questions about vegetarian eating and mental health
Does a vegetarian diet really make you depressed?
By the current data it cannot be put that way. There is an association: a meta-analysis of observational studies from 2022 found a 53 percent higher depression risk among vegetarians. A meta-analysis from 2025 that pooled twenty longitudinal studies only found the opposite, namely a 26 percent lower risk. Association is not causation, and here in particular there are good reasons to think about the reverse direction. In German data the dietary change follows the onset of the mental disorder, it does not precede it.
Why does one study say 53 percent more depression and the next one 26 percent less?
Because they pool different study types. The analysis with the 53 percent pools mostly cross-sectional data, that is, snapshots in which eating and mood were recorded at the same time. The analysis with the 26 percent less pools longitudinal studies only, in which eating was recorded before depression appeared. This is exactly the shift you would expect if a large part of the cross-sectional finding comes from reverse causation. So both numbers can be right and still measure different things.
Is it true that the association shows up in Europe and the USA but not in Asia?
In one subgroup analysis it looks that way. In studies from Europe and the USA the odds ratio was 1.45, in studies from Asian countries no association showed up. That finding comes from exactly one meta-analysis, heterogeneity in the Western group was high, and another research group explicitly points out that almost all studies come from Western countries. A regional difference is plausible, but the data behind it are thin. A subgroup is a hint, not evidence in its own right.
I went vegetarian recently and I am tired all the time. What can be behind that?
Several reasons come into question, and guessing gets you nowhere here. Common ones are a low iron store, a functional vitamin B12 deficiency, a tight zinc supply, a low omega-3 index or simply too little protein and too little energy overall. In vegetarians serum ferritin lies clearly lower on average than in non-vegetarians, in men especially so. It makes sense to have blood drawn before you take anything. Persistent tiredness also has many causes beyond eating and belongs in medical hands.
I am already taking iron and B12 and it is not getting better. What now?
Three possibilities are common. First: the store needs time, ferritin usually rises over months and not over weeks. Second: absorption is not working, for example with an inflamed gut lining or unfavourable timing. Third: something is missing at a completely different place, for example EPA, zinc, vitamin D, the thyroid or sleep. Instead of raising the dose, checking the values is the clearer path, and with medical interpretation.
Which blood values should I know as a vegetarian?
As orientation: ferritin together with CRP, because inflammation can shift the ferritin value upward, plus a blood count. For vitamin B12 a functional marker says more than serum B12, so holotranscobalamin or methylmalonic acid, complemented by homocysteine. On top of that zinc, vitamin D and, if the fatty acid axis interests you, the omega-3 index from the red cell membrane. Which values make sense for you and how to read them belongs in a medical conversation.
Is flaxseed oil enough as an omega-3 source if I do not eat fish?
By the best overview so far, rather not. A scoping review of thirteen randomised trials compared plant omega-3 sources by the omega-3 index, that is EPA and DHA in the red blood cell. High-dose flaxseed oil and echium oil did not raise this index, in individual trials it even fell. Microalgae oil raised it in every trial. If the mood aspect interests you, it is also relevant that in meta-analyses mainly EPA-weighted preparations showed an effect and pure DHA formulas did not.
Is a vegetarian diet risky for the mental health of children and adolescents?
There is barely any solid data on mental health for this age group, so a clear statement in either direction would not be covered. What is well documented is the supply side: in a systematic review the rates of vitamin B12 deficiency in vegetarian children ranged from 25 to almost 86 percent and in adolescents from 21 to 41 percent, each determined through functional markers. A vegetarian diet during growth is possible, but it needs guidance, regular checks and a paediatric assessment.
What is the difference between vegetarian and semi-vegetarian, and why does that matter for studies?
Semi-vegetarian means that meat or fish is eaten occasionally, often during a transition phase. In the 2022 meta-analysis it was precisely this group that was most strongly associated with depression, with an odds ratio of 1.86, while lacto-ovo vegetarians showed no association. That fits a simple deficiency model badly, because anyone still eating fish and meat has fewer supply gaps. It fits better with the idea that in transition groups many people are in the middle of a change, for very different reasons.
Should I eat meat again if I am doing badly mentally?
That is not advice I will give you, and the data do not support it either. The more sensible order is: measure first, then close in a targeted way what is actually open. If depressive symptoms last longer than two weeks, interfere with everyday life or come with hopelessness, that belongs in medical or psychotherapeutic hands, independent of any way of eating. Food is one of several factors and never the only one.
Why are vegetarians more common in studies on eating disorders?
Because for some people a restrictive way of eating is a way to keep control over food. In one study of three groups, the share of those who had ever lived vegetarian rose from 6.8 percent without an eating disorder to 17.6 percent with disordered eating and 34.8 percent in inpatient treatment. In a case control study, 52 percent of women with a history of an eating disorder had ever been vegetarian compared with 12 percent of controls, and the share fell with the degree of recovery from 33 to 5 percent. That skews statistics about vegetarians as a whole. About you as an individual reader it says nothing.
What actually makes a vegetarian diet a good vegetarian diet?
The studies that separate plant-based food by quality give the clearest answer. In the UK Biobank with 180,532 people, a healthy plant-based diet was associated with a hazard ratio of 0.92 for depression, an unhealthy plant-based diet with 1.15. Healthy meant plenty of vegetables, fruit, whole grains, legumes, nuts and seeds. Unhealthy meant plenty of white flour, sugar, sweetened drinks and heavily processed products. So the difference does not lie in the vegetarian label, it lies in what you replace the meat with.
Vegetarian eating in the bigger picture
Mood never arises in a single place. It hangs on iron, on inflammation, on sleep and on mitochondria. From here, paths lead into other areas of the practice.
Vegetarian and the mind
Two meta-analyses, gene variants, food culture
this articleIron deficiency and the mind
Irritability, low drive and the ferritin link
Sleep and depression
The bidirectional circle that plays a part here too
Burnout, gut, inflammation
What is documented and what stays a hypothesis
Scientific sources
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