Entirely personal anecdotal experience over the past few years on four different sites: the majority of the emotional downdraft of deconversion is in the initial decision and the early months following. That's where you lose your entire social support system, likely the only one you (1) have and (2) know. Possibly where your marriage turns to shit or ends, your children are mostly taken from you (if you're a man), and all that sort of thing. But even short of that -- you have become what you once despised and were taught to hate, you may feel great guilt and shame, you will certainly have people trying to heap that on you.

I would be surprised if reactive depression didn't occur as a result of turning from religion to atheism.

Apart from deconversion, however, I doubt that even lifelong atheists are objectively more prone to depression as if in a vacuum, but rather, that they carry more risk factors for it. Depression and anxiety (two sides of the same coin really) are largely a function of social disconnection, and there is going to be more of that for a social outsider than for an insider. The blame for this doesn't lie with atheism, it is simply the situation in which an atheist finds themselves. If there's blame, it's on society for not being sufficiently inclusive and respectful of difference, and the main influence for exclusion of atheists would be theists. As usual, they create a situation and then blame the victim.

[onlinelibrary.wiley.com]
Here is a link to a source that sees this as a serious question . To read the articles you have to subscribe. I will look further for other research.
Good question

Anything can be linked to depression/anxiety. Depends on our personal triggers, I think.

Only if one is obsessed, like your Christian friends, with promoting and tryting to force your ideas on the true believers. I let a lot slide when I hear the several "Christians" at my work talking religion. It's not my place to educate them. And you can't really do that anwyay, they are too close minded, and their religion gives them a fantasy comfort that they don't have to worry about death. I hear that a LOT. They are obsessed with suviving death. They really feel that they are SO important and special in this vast universe that they cannot conceive of themselves not being a part of it. Forever! And yet, if I answer their question, "What do YOU think happens when you die," by saying, it's as if you were never born. Or to put it another way, it's as it was BEFORE you were born, they cannot even begin to digest that and understand it in any way. It's totally beyond their understanding. The universe has existed for 14 BILLION years (or 61 Galactic Years) without you or I in it, and I think it will continue quite well without us. Well, the first problem there is, they believe that Earth is only 6,000 years old, and that every living thing we see today came into existence wholly formed, 6,000 years ago. And that one day their "god" will call them "home."

It's fascinating to watch, but not depressing. Just sad over their ignorance and failure to grow as a fully functioning human being. Even Shakespeare understood this about human existence!

“Tomorrow, and tomorrow, and tomorrow,
Creeps in this petty pace from day to day,
To the last syllable of recorded time;

And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!

Life's but a walking shadow, a poor player,
That struts and frets his hour upon the stage,
And then is heard no more.

It is a tale Told by an idiot, full of sound and fury,
Signifying nothing.”

— William Shakespeare (from Macbeth, spoken by Macbeth)

I think that understanding you won't see your loved ones in heaven is in itself depressing, but far better than still being asleep. I've had anxiety issues since I was a small child, I guess because my mother died when I was four. I wouldn't say my non belief caused any of it, but instead it comforts me to know that I'm a good person without the threat of hell.

Christianity teaches man is a wicked, sinful creature needing a redeemer. I tend to think man could be and SHOULD be a heroic figure in his own life.

I wouldn't think atheism would be linked to depression or anxiety at all. I'd suspect religion would, but few religious people would know/admit it. And if there were statistical data to show similar numbers, then perhaps the problem is biological, not ideological.

Only one question comes to mind...... Why???

Interesting to ponder. I think the belief in a god does/must give a certain comfort. There are actually times I have envied the blind faith of some people I know. It would have made a number of things I have dealt with easier to bear I suppose. Unfortunately, or fortunately, i'm completely incapable of buying in to the god thing. I do work with people with serious mental health issues and find many/most believe in god. That also confounds me. The suffering they live with due to their mental illnesses certainly would make you think that if they believe in a god, they should be completely and utterly pissed off at him. Yet, again - this is where they go for some sort of comfort. The God concept is a balm in a world of wounds to many people.

Why would that be so? I don't see the connection. I think the imbalance of certain brain chemicals is connected to anxiiety and depression. I have never heard the psychologist say"go to church. You'll feel better."

No.

lack of atheism seems to cause depression, maybe we can put it into a pill?

I was going to say I was diagnosed depressed and I am atheist but how that relate to the depressed christian?

Mental health struggles cross any lines we draw. Economic, racial, spiritual, any delineation is susceptible to experience a mental illness. Recovery promotes choice, hope, empowerment, and purpose and meaning (also called spirituality if that's your experience) in a recovery environment... So some people will experience depression and anxiety as a percentage of the population you're examining. (If you consider choice and empowerment they may resonate more in a less patriarchal oppressed group...)

Being alive and seeing the current state of the world, environment, politics, inequality are all justifiable reason to feel depressed. I feel sad for where we have gotten ourselves and our prospects as a planet. Not having an imaginary omnipresent saviour to step in and fix it all makes it a bit more real.

However, I’m not personally ‘depressed’ and day to day in my own life I’m relatively happy, but definitely a realist.

@Daco2007 “It's not my place to educate them.” But pretty please try?

The only objection I have to the word is that it is negative. Humanist is both positive -about Humans and shows the correct focus after leaving god. As you know depressives are a bit short on positivity.

Current scientific data is inconclusive.

A longitudinal Canadian study from 1994 to 2008 found that, after controlling for other factors, people who attended religious services at least monthly were 22% less likely to suffer from depression.

However a 12-month longitudinal study published in 2013 spanned seven countries and found a slightly lower incidence of depression among non-religious people than among religious or "spiritual" believers (7% for "secular", 10.3% for "religious", and 10.5% for "spiritual" ). The latter survey noted significant variance from country to country, and in particular noted that in the UK, "spiritual" participants were three times more likely to experience an episode of depression than the "secular" group.

No correlation.

I would believe not related, If anything belief in a punishing god will cause depressiona and of course anxiety. I went through depression before and it was not lack of god that bothered me, it was lack of me believing in myself.

Evidence one way or the other wouldn’t surprise me. If it is linked I definitely would assume causality in the direction of depression>atheism rather than atheism>depression. If you have a tendency to focus on what’s bad/sad in the world, you’re much more likely to realize this place definitely wasn’t intelligently designed.

Its very possible

Nope

Not that I know about; the only thing that depresses me is people trying to re-educate my mind to conform to theirs.

I don't really see how atheism ,could lead to depression because it isnt a thing of itself - My atheism is of absolutely no account to me its not guiding me in any way its a non event its like not wanting to eat custard or mustard its just a choice to not do something -

I don't get depresed every time i don't eat custard which i don't like. I think this question liek many others is aimed at people who started out believing in an entity I have never ever had a god in my life and am not likely to at &0 y.o never having a god in teh forst place.

I do not think that is the case, although I suspect that it could be in a minority of cases.