Unexplained Sadness: Why It Happens and What You Can Do About It

Sometimes, you feel sad for no apparent reason. Find out why and what you can do about it.
Unexplained Sadness: Why It Happens and What You Can Do About It
Valeria Sabater

Written and verified by the psychologist Valeria Sabater.

Last update: 21 December, 2022

Do you sometimes wake up in the morning feeling strangely apathetic and sad for no particular reason? Furthermore, you find your body reacts more slowly than normal and any stimulus, such as light or even loud noise, hurts you. What causes this?

Something inside you tells you that you’re sad, and you feel strangely oppressed by an undefinable feeling you just can’t explain. These are the kinds of days when, if someone looks at your expression and asks what’s wrong with you, you say,  “I really don’t know. I guess I’m just having a bad day today”.

Whilst there are times when sadness can have a pathological origin, most of the time its origin is clear. However, in reality, your brain and body are a cluster of chemical reactions that sometimes generate sensations in you that you’re not aware of.

Nevertheless, you usually continue working on automatic pilot, which means you can’t see what’s really happening. This is despite the fact that your brain is giving you alarm signals that there’s something that needs solving.

Why do you feel unexplained sadness?

sad boy surrounded by leaves

Sadness envelops and catches you suddenly, your body feels heavier, and you feel extremely tired and apathetic. It’s worth remembering that you certainly aren’t alone in feeling this way as it affects many people. Therefore, l et’s take a look at some of the possible causes of unexplained sadness.

1. External factors

An incorrect diet can be one of the reasons. It happens when you follow an extreme diet where you stop eating the nutrients that your body needs.

For example, a diet low in protein, vitamins, minerals such as iron, magnesium, or phosphorus, can cause the weakening of many basic functions. Indeed, when your body isn’t well-nourished, your mood declines and you feel weak.

Another factor could be seasonal affective disorder. That’s because the weather affects you. In fact, you may well find that, when winter arrives, with fewer daylight hours, more rain, and humidity, you’re affected by a kind of sadness that can’t be explained and that can often lead to depression. Furthermore, your sleep cycles are altered, and you experience feelings of fatigue and apathy.

2. Internal factors

Women showing sadness that has no explanation

First of all, you should know that, at the nervous level, when you feel sad, you suffer a drastic drop in neurotransmitters such as norepinephrine and serotonin in your brain. This is what causes your feelings of unexplained sadness. However, what causes this sudden deficit in these neurotransmitters?

As a matter of fact, it’s due to external factors. Personal factors are the most common. Because sadness doesn’t appear suddenly for no reason at all, it always has an origin.

For instance, you might be leading a normal life when, suddenly, you begin to notice some strange signs. For example, headaches, tiredness, illnesses like colds and flu. This is because your immune system is weakening and you’re suffering what’s called somatization. In other words, your body is reacting to the concerns of your mind.

In your brain, your hypothalamus responds to these concerns by secreting corticotropin, which, in turn, stimulates the secretion of cortisol in your blood. All of this affects your behavior and feelings. Therefore, you feel more tired, worried, and withdrawn.

There’s always a reason

Girl with umbrella symbolizing sadness
There’s always a reason for the kind of sadness that you think has appeared out of the blue. Your body will be the first to give you the alarm signal to warn you that you have to stop. In fact, you need to think and take account of what’s happened in order to clarify what’s really worrying you.

However, you often deny that these problems even exist because you’re unable to stop. You have so many obligations… work, children, your partner. The rush of your daily life is like a well-oiled machine that sometimes prevents you from being a person.

Therefore, you must sit and reflect. Talk to yourself and accept the fact that you’re not as well as you think. Remind yourself that you’re not invulnerable and that there’s clearly something that’s hurting you that you must solve. Take off your armor. Find out what’s at the end of that unraveling thread in your mind.

Your body has already given you a clue that you’re not well. Start to take care of yourself. Think of your inner world, the one that keeps your life moving.


This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.