Why do we feel better at night?


Senior Member
Upstate, NY
Boy this is a big one for me. I feel the best when I don't sleep well (only time I feel better in the mornings) and I feel really good at night sometimes (my elevated HR lowers, calmer, and I have much less PEM / brainfog). I believe this has to do with immune exhaustion. I bet the later we stay up our immune system gets disrupted, might have to do with HPA axis or T cell exhaustion. Who knows. When I used to be normal sick I would sleep a lot and get better like a normal person, with ME/CFS im to wired to sleep and eventually I feel better without sleep, sleep well when symptoms decrease and then feel awful, then the process repeats. It would be great if they would study the diurnal changes in ME/CFS patients. Reminds me some sever patients not being able to tolerate visitors before 3pm. This definitely is a neuro-immune disease in this respect.


Senior Member
Add me to those who often feel better in the evening. As others say, it's a fairly abrupt switch. I may not feel wonderful, but I do feel more alert and energetic.

I assumed it was due to hormone swings, such as cortisol. For quite a long time, I'd feel abruptly worse at around 2:30 PM, and that time didn't seem to vary with when I ate, slept, etc. I just assumed it was somehow linked to the circadian rhythm. That led me to try tryptophan, to see if it would influence that switch...which led me to discover that tryptophan greatly increased my symptoms severity. I didn't find out if it affected the time thing. Instead, I changed my diet to avoid tryptophan as much as possible, which didn't help much either.


Senior Member
I feel better in the late afternoon, early evening too.

And, every morning I'm sick with sweats, chills, sinusitis, IBS issues, which I believe may be mast cell related.

But now I'm thinking some kind of cytokine circadian thing might be at play.


I kept a health diary for a long time where I broke down how I felt not just each day but at various points throughout the day. The clear statistical message of many months of data was that I felt better at night.

This is not always the case. It's not an everyday thing. If I'm very unwell I defintiely just need to sleep and I go to bed early. But on average, nights are better. I understand the metabolism is designed to do different things at night, (1, 2) and is prompted to change itself based on various signalling molecules. It would be interesting to see if we can identify these changes.

An evolutionary biology hypothesis: if the dauer/hibernation/hypometabolic state is operating to prevent us from overexerting, it need not operate at night, because there is much lower risk of over exertion at night. (Indeed, for the trait to be conserved throughout the generations it might be useful to be more active at night! ;) )


As a total side note here on the nature of well-known hypometabolic states: We imagine bear hibernation to be a snuggly cosy time. Probably based on various cartoons. But what if the bears hibernate because they feel like absolute shit?
I also think this is an interesting area that could do with more investigation.

I've never been a "morning person" but I think this is quite different.

One thing I've been experimenting with is increasing dose of magnesium and b12 before bed, which so far seems to have an effect by reducing the nausea/cognition problems on waking. I have also noticed that when high histamine symptoms are high during the day before then this seems to intensify the nausea etc the following morning.

This makes me think that there is something in the metabolism that's not working properly that makes sleep/ waking transition slow/sluggish. I wonder what the bodies start up metabolic processes are and how energy hungry they are vs the metabolism demands while you are asleep.
I would like to put forward another suggestion. Irlen syndrome. Look at the research of Leow. He concluded from a tiny study that all with me/cfs have irlen. The problem with Irlen I that symptoms are diverse ad what one has another may not. Sadly expect at the first mention of education problems the idea is dropped by many. Try deeper,head aches,migraines,depth perception problems, sleep, need too much or not enough. Brain fog, blurry/distorting words on a page. Depression,anxiety,raised Anger levels.
point is that we do not have to live with these,problems there I a simple solution.


as long as you manage to stay alive, there's hope
There is a few reasons why some may be feeling better at night

1/ if at night you are laying about more (laying on sofa or bed doing things), this can help quite a lot if you have POTS with the ME. (so consider you may have POTS if you are better at night when laying more)
2/ one can feel more awake/less tired at night if ones circadan rhythm is reversed
3/ I know one of the hormone how it cycles (I forget now which) can be also the cause of someone feeling better at night.
certainly my circadian rithm is reversed. If it wheren't for the "sleeping pills" I would sleep at day and be awake all night, as I used to. I feel better at night indeed


ME/CFS since 1995; activity level 6?
Cornwall, UK
I see so many people on this board, including myself, experience this. I almost feel normal at night.

Surely, if the reason for this phenomenon was investigated maybe we could come closer to finding an answer to this syndrome?

When I think of all the times I had an infectious disease, I in fact feel the worst at night time, even with the common cold, I dread the way I begin to feel when night time hits.

But this disease; it's almost the opposite. Makes me wonder if an infection is really behind it at all.

I've also spoken to many people with mood disorders as well who've said they feel better at night. The conditions must share something in common in terms of the pathological process.
Yes. It's the cortisol, I reckon.