Nutrition for shift work

A practical guide to eating around shift work: when to eat, how much protein, how to time caffeine, and what to pack for a night shift.

Shift work doesn't wreck your diet on its own — the chaos around it does: the vending machine at 3 a.m., the first real meal at 4 p.m., and coffee right up to the last minute of the shift. Your body handles carbohydrates worse at night and empties the stomach more slowly, so the same plate at 3 a.m. is not the same plate at 1 p.m. Here is a plan that survives a schedule that changes every week.

Why night changes the rules

Insulin sensitivity is measurably lower at night — after an identical meal, blood sugar runs higher and takes longer to come back down. On top of that, gut motility slows in the second half of the night, which is why a heavy, greasy meal at 4 a.m. is the most common cause of nausea and heartburn near the end of a shift. The practical conclusion: night is not the time for the biggest meal of the day, no matter how hungry you feel.

The second issue is volume. If you eat 800–1000 kcal overnight and still return to your normal daytime meals, you've added a whole extra meal — roughly 3–4 kg a year with no change in training. Aim to keep overnight intake at 300–500 kcal, split across one or two short breaks.

How to lay out your meals

Night shift (10 p.m.–6 a.m.)

Main meal before the shift, around 8 p.m.: 35–45 g protein (about 180–200 g chicken or 200–250 g fish), 80–120 g rice or buckwheat measured dry, plus a large portion of vegetables.
First break around 1 a.m.: 250–350 kcal weighted toward protein and fibre — 200 g yoghurt or quark, a piece of fruit, 20–25 g nuts.
Second break around 4 a.m., if the shift runs to morning: 150–200 kcal. Two slices of wholegrain bread with 60 g cheese, or two hard-boiled eggs. Nothing fried, no processed meat, nothing sugary.
After the shift, before sleep: something small, 20–30 g protein and a little carbohydrate. Go to bed hungry and you'll wake up after four hours; go to bed stuffed and you won't fall asleep at all.

Afternoon shift (2 p.m.–10 p.m.)

The easiest one to organise. Light breakfast at 9–10, main meal at 12–1 before you leave, a 400–500 kcal meal around 6 p.m., and after 10 p.m. only something small if you're genuinely hungry. The real risk on this shift is the habit of eating a third of your daily intake in front of the TV at 11 p.m.

Early morning shift (6 a.m.–2 p.m.)

If you're up at 4:30, don't force a big breakfast. 15–20 g protein and a slice of bread is enough; make the 9 a.m. break your real breakfast. Move the main meal to 2–3 p.m., straight after work, so dinner doesn't land too late.

The daily frame, whatever the shift: 1.6–2.2 g protein per kilogram of bodyweight (for 80 kg that's 130–175 g a day) spread over 3–4 meals of 30–45 g each, and 25–35 g of fibre. Fibre is the first thing to disappear on shifts, and digestive problems follow. Put most carbohydrates around training and in the pre-shift meal.

What goes in the box

The rule that solves eighty percent of the problem: if the food isn't packed before the shift, you'll eat whatever is closest. Two containers per shift is enough.

Big box: 150–200 g cooked meat, fish or legumes, 200 g cooked rice or potatoes, and vegetables.
Small box: 200 g yoghurt or quark, fruit, 20–30 g nuts.
Backup in your locker: a tin of fish, oats in a jar, honey. When a shift runs two hours over, that's the difference between a meal and three chocolate bars.
Water: a one-litre bottle on the desk, aiming for 200–300 ml per hour worked. At night, dehydration usually shows up as hunger.

Caffeine: dose and timing

Caffeine works, but only if you dose it. 100–200 mg (one or two coffees) at the start of the shift, another 100 mg mid-shift if you need it, then nothing for at least 6 hours before you plan to lie down. If the shift ends at 6 a.m. and you sleep from 7, your last coffee is at 1 a.m.

The practical ceiling for most people is around 400 mg a day. An energy drink before the shift plus three coffees overnight clears 600 mg easily, and you pay for it with shallow sleep and higher blood pressure.

Sleep and training around the shift

Sleep is part of nutrition: after a 5-hour night, cravings for sweet food rise measurably the very next day. Target 7–8 hours, or 6 hours in one block plus a 60–90 minute nap in the afternoon. Keep the room dark (blackout blinds or a mask) and cool, 18–20 degrees.

For training, hold 2–3 strength sessions a week and don't cram them all into your days off at the cost of recovery. A workable session: 4–5 compound lifts, 3 sets of 5–8 reps on the heavy work and 3 sets of 8–12 on the rest, 45–60 minutes total. Don't hit the gym straight off a night shift before you've slept — training on four hours of sleep costs more than it gives.

When to see a doctor

Shift work is a risk factor, not a diagnosis, but some things shouldn't be self-managed:

Heartburn or reflux more than twice a week, or recurring stomach pain.
Gaining 5 kg or more in 6 months with no change in diet or training, or a waist over 94 cm in men and 80 cm in women.
Constant fatigue despite 7–8 hours of sleep, loud snoring, or breathing pauses during sleep that someone else notices.
Known diabetes, high blood pressure, thyroid disease, or medication that has to be taken at fixed times — a doctor adjusts that schedule around your shifts, not you.
Insomnia lasting more than a month that doesn't improve even on days off.

At a check-up, ask for fasting glucose or HbA1c, a lipid panel, and blood pressure: once a year if you work nights, more often if something has already been out of range.

No meal schedule cancels out chronic sleep debt. Eating well on shifts is damage control; sleep is the actual treatment.

The short version

Eat your largest meal before the shift, and keep overnight intake to 300–500 kcal across one or two breaks.
Protein 1.6–2.2 g per kilogram of bodyweight daily, split into 3–4 meals of 30–45 g.
Caffeine 100–200 mg at the start of the shift, last dose 6 hours before sleep, under 400 mg total per day.
Pack two containers before every shift and keep a backup in your locker — that removes most bad choices.
2–3 strength sessions a week, 3 sets of 5–8 or 8–12 reps; after a night shift, sleep first, gym second.