Motivating yourself to keep going despite obstacles helps, but pushing yourself to the limit does not. You may need to be careful: chronic stress can hurt you—and perhaps your chances of success as well.

Stress is what happens when you perceive, or at least feel, that the demands life is placing on you are greater than your ability to cope. Sometimes stress can be helpful, giving you the impetus and focus to achieve. But stress can also be a trade-off: are you toughing it out because you know the short-term strain will be worth the long-term benefits, or has the short-term harm started to become a long-term liability? In short: how much stress is too much?

The dangers of stress

We all know stress is an uncomfortable sensation; what we don’t always realize is that it can be damaging. There are many ways in which the brain’s chemistry, structure, and even physical size can be adversely affected by chronic tension (see “How stress affects the brain,”). Chronic stress doesn’t just increase your risk of physical illness (though it does that, too); it also makes you less motivated and, literally, less intelligent. Our bodies are designed to respond automatically in times of threat: this makes sense if you’re fleeing a bear, since you act faster when you’re operating on instinct, but if you’ve ever found yourself freezing in an interview or getting stuck during a presentation, you’ll know there are times when it undermines you. Severe stress simply makes you do worse at the tasks you’ll need to perform well to succeed. When you consider that it also increases your chances of mental illness—something that can incapacitate the most talented—you’ll know that it’s something you need to keep in check.

What can you do?

The important question is this: when you feel you can’t cope, where does that feeling come from—the situation, or your faith in your coping abilities? Both are possible, and neither is “wrong,” but each answer calls for a different solution. If you’re in a chronically stressful situation, you may need to revise your plans: a stressful period that will definitely end may be endurable, but you can’t succeed if you burn yourself out.

If you feel you have to stick with the situation, there are ways you can at least moderate your stress levels. None of these suggestions represents a magic bullet, but try them out and see what works for you.

A successful life includes a level of stress you can tolerate over the long term. You may be stronger than you believe—but it is also sensible to listen to your instincts, and to take action when necessary.

how Stress affects the brain

Stress physically changes your brain in a variety of ways:

• Too much “white matter” (myelin) develops. In a healthy brain, this provides an insulating electrical sheath enabling nerves to send their signals efficiently. In excess, it overinsulates, slowing down connectivity between different parts of the brain
• The protein BDNF (brain-derived neurotrophic factor) is slowed down. Because BDNF is responsible for the development and differentiation of new brain cells, this impedes the brain’s functioning and can increase the risk of mental illness, dementia, and Alzheimer’s
• Levels of dopamine and serotonin, hormones associated with happiness and well-being, drop. In mild cases this leads to a habitually lowered mood; in more extreme cases, it increases the risk of mental illness and addiction
• The brain’s immune cells (microglia) get overactivated, risking brain inflammation
• The thalamus, which helps create the fear response, becomes habitually overactive
• The sensory cortex sends stronger fear signals to the body, creating physical symptoms such as muscle tension, stomach upsets, and restlessness
• The hippocampus shrinks, reducing self-control, memory functioning, and emotional regulation
• The pituitary gland stimulates the adrenal glands in the torso, releasing more of the “stress hormone” cortisol.

Your brain is a physical organ, so take care of it. If you’re really stressed, remember that it’s not a sign of weakness to take a rest: it’s sound medical sense, and much better for you in the long run.