Shift work: why it's hard on the body and how to help it

You come home at six in the morning, just as your neighbors are getting up for work. The curtains are drawn, but light still filters through. Your body is tired, yet your mind is racing – your internal clock simply doesn't know what time it is anymore.

Shift work is a reality for hundreds of thousands of people in Lithuania: medical professionals, factory workers, logistics personnel, and salespeople. What might be inconvenient working hours for one person is a constant balancing act between a work schedule and one's biology for another.

In this article, we will simply explain what happens in the body when we work against our body clock, and what can be done to make this burden easier for the body to bear.

What happens in the body during shift work?

Each of us has an internal biological clock – a circadian rhythm. Over approximately a 24-hour cycle, it regulates almost everything: when we feel alert, when we want to sleep, when the digestive system is active, and when it's in rest mode. The primary regulator of this clock is light.

Shift work turns this mechanism upside down. Imagine flying to another continent every few days and then returning. This is exactly how the body feels when day and night shifts alternate in the schedule. And an important fact: even after many years of night work, the circadian rhythm never fully recalibrates to nocturnal wakefulness. The internal clock still "thinks" that night is for sleeping.

How does this feel on a daily basis?

Daytime sleep after a night shift is often shorter and shallower – by an average of 1–2 hours. The sleep structure also changes: deep sleep phases, during which the body regenerates, become shorter. Even after 7 hours, we might feel as though we've only slept 5 hours or even less.

The digestive system naturally goes into rest mode at night. The stomach produces less acid, insulin sensitivity changes, and the body is not prepared to process food. Therefore, for shift workers, it is especially important to pay attention to meal timing and food composition.

Add to this the feeling of fatigue, difficulty concentrating, and an altered cortisol rhythm – and we understand why conscious self-care becomes not a luxury, but simply a daily necessity.

What can shift workers do?

While we cannot change the nature of shift work, we can significantly alleviate its burden on the body.

Light management – the most powerful tool. During a night shift, try to be in a brightly lit environment. On your way home, wear dark glasses to prevent the morning sun from disrupting melatonin production. And your bedroom for daytime sleep should be as dark as a cave – investing in quality curtains pays off handsomely here.
Nutrition strategy. Eat your main meal before your shift. At night, choose light snacks – nuts, vegetables, yogurt. Avoid heavy foods and fast carbohydrates. And that craving for sweets at night? That's not a lack of willpower – when the body needs extra energy, the brain sends a signal "give me sugar!" It's biology, not a character flaw.
Caffeine window. Caffeine works well at the beginning of a shift, but it stays in the body longer than it seems – half is eliminated in 5–6 hours. So, a simple rule: drink coffee only during the first half of your shift. Caffeine should be out of your system 4–6 hours before bedtime.
Sleep hygiene. The room should be cool (about 18 °C), quiet, dark. The phone should be in another room. And family members should be aware of your sleep time – it's not a whim, but a matter of health.

Especially important nutrients

A body operating in an unusual mode consumes more resources. Several substances whose demand naturally increases for shift workers:

Vitamin D. In Lithuania, most people get insufficient vitamin D, and night workers especially so, as they receive minimal sunlight. Vitamin D helps maintain normal immune system function and normal bone health.
Magnesium. Helps maintain normal nervous system function and contributes to reducing feelings of fatigue – two things that are particularly relevant for shift workers.
B vitamins. Help maintain normal energy metabolism – when you eat irregularly and at suboptimal times, this function becomes even more important.
Melatonin. Helps fall asleep faster at an unusual time, but in the EU, higher doses are prescription-only. The dose should be small, and it is essential to consult a doctor before use.

What no supplements can do

Sleep first – this is the most important thing a shift worker can do for themselves. Sleep is not "if there's time left over." It's the first item on everyone's daily agenda.

Physical activity, regular nutrition, and regular health check-ups – all these form the foundation on which supplements can work effectively. Supplements are just supplements – they complement a healthy lifestyle, but they don't rescue you from its absence.

Summary

Shift work is a challenge that the body never fully adapts to. But by understanding the circadian rhythm and why the body reacts the way it does, we can help it function as smoothly as possible – even when circumstances are not ideal.

Frequently Asked Questions

Can you get used to night shifts?
Subjectively – yes. However, the internal biological clock never fully adapts, especially if you revert to a daytime rhythm on your days off.

Is it worth taking melatonin for daytime sleep?
It can help, but the dose should be small, up to 1 mg. It is essential to consult a doctor.

Which shifts are the hardest on the body?
Rotating schedules are a greater challenge than permanent night work. If the shift schedule rotates, a forward shift (morning → day → night) is always better.