7–9 h
Sleep adults need
Adults need 7–9 hours of sleep a night for good health.
Source: AASM / Sleep Research Society 2015
Sleep & energy
Good sleep is the foundation of steady energy, a healthy weight and a clear mind. What you eat and drink affects how well you sleep.
Sleep in numbers
7–9 h
of sleep a night is recommended for adults
1 in 3
adults regularly don't get enough sleep (CDC)
400 mg
caffeine a day is the safe upper limit for most adults (EFSA)
~5 h
is the average half-life of caffeine in the body
How much sleep you need
| Age | Hours per day |
|---|---|
| Babies 4–12 months | 12–16 (with naps) |
| Children 1–5 years | 10–14 |
| Children 6–12 years | 9–12 |
| Teens 13–18 years | 8–10 |
| Adults | 7–9 |
| Older adults 65+ | 7–8 |
Eat for steady energy
Don't skip breakfast
Protein plus fibre (eggs and whole-grain bread, or oats with nuts) prevents a mid-morning crash.
Balance every meal
Combine protein, fibre and healthy fat to avoid blood-sugar spikes and dips.
Stay hydrated
Even mild dehydration can make you tired and unfocused.
Watch the sugar
Sweets and soft drinks give a quick lift then a slump.
Check iron and B12
Low levels are common causes of tiredness.
Move
A 10-minute walk boosts energy more reliably than a snack.
A better evening routine
- Keep the same bedtime and wake time, even at weekends
- Avoid caffeine after about 2 pm
- Finish large meals 2–3 hours before bed
- Dim lights and put screens away 30–60 minutes before sleep
- Keep your bedroom cool, dark and quiet
- If you can't sleep after 20 minutes, get up and do something calm
Foods and drinks before bed
May helpMay disturb sleep
Warm milk or yoghurtCoffee, strong tea, energy drinks
A banana or a few datesHeavy, spicy or fatty meals
Herbal tea like chamomileAlcohol — it fragments sleep
Kiwi or tart cherriesLarge amounts of fluid late at night
See a doctor if
- You feel exhausted for weeks despite enough sleep
- You snore loudly or stop breathing in your sleep
- You fall asleep during the day without meaning to
- Insomnia lasts more than three months
World health facts
All facts1 in 3
Adults short on sleep
About a third of adults regularly sleep less than 7 hours.
Source: CDC
400 mg
Daily caffeine limit
Up to 400 mg of caffeine a day (about 4 cups of coffee) is considered safe for most adults; 200 mg in pregnancy.
Source: EFSA 2015
+55%
Higher obesity risk in short sleepers
Short sleep was linked to a 55% higher risk of obesity in adults and 89% in children.
Source: Cappuccio et al., Sleep 2008
Related articles
More in Mind & Life
Sources
- • American Academy of Sleep Medicine & Sleep Research Society (2015)
- • NHS — Tiredness and fatigue
- • EFSA caffeine safety opinion (2015)
- • CDC sleep and health data
General information based on public health sources, not medical advice. Talk to a doctor or registered dietitian before major changes, especially if you are pregnant, have a health condition or take medication.