Being tired by mid-afternoon, needing a third coffee to get through the day, waking up already drained: these are some of the most common health complaints there are. A lot of the advice on how to increase your energy levels naturally is a list of tips with nothing behind it. This guide sticks to what research and health services actually say: which habits make a measurable difference to energy, which hidden problems commonly cause fatigue, and when tiredness is a reason to see a doctor rather than try another tip.
This is general information, not medical advice. Tiredness that lasts for weeks without an obvious reason is a symptom worth getting checked, not something to push through on willpower.
Table of Contents
First, Is It Tiredness or Something Else?
Most day-to-day low energy has ordinary causes: not enough sleep, poor-quality sleep, stress, too little movement, irregular meals, or caffeine and alcohol working against you. Those are what most of this guide covers, because they’re where most people have the most room to improve.
The NHS also lists medical causes that are easy to miss. These include iron deficiency anaemia (often with noticeable heartbeats, shortness of breath and pale skin), diabetes (with extreme thirst, frequent urination and weight loss), an overactive or underactive thyroid, depression, and ME/chronic fatigue syndrome (severe fatigue lasting at least three months, with memory and concentration problems). Its advice is to see a GP if you’ve felt tired for a few weeks and don’t know why, if tiredness is affecting your daily life, or if it comes with other symptoms such as weight loss or mood changes. A doctor may order blood tests to check for anaemia, diabetes or thyroid problems.
To go into that appointment prepared, see our guide to the blood tests to ask your doctor for when you’re tired all the time.
If you sleep a full night and still wake up exhausted, read our deeper guide: Why Do I Feel Tired All the Time Even After Sleeping 8 Hours?
Another specific cause worth knowing the signs of: if you sleep a full night but still feel unrested every single morning, see our guide to sleep apnea signs for the screening questions and when home testing makes sense.
1. Sleep: Enough Hours, and Good Ones
The American Academy of Sleep Medicine and the Sleep Research Society published a joint consensus statement in 2015 (Watson et al., Journal of Clinical Sleep Medicine). It recommends that adults sleep 7 or more hours per night on a regular basis. Regularly sleeping less than that was associated with weight gain, diabetes, high blood pressure, heart disease, stroke, depression and a higher risk of death. Fatigue is the most immediate cost, but it isn’t the only one.
Hours in bed aren’t the whole story. Obstructive sleep apnoea, where the airway repeatedly narrows or closes during sleep, breaks up sleep without the person necessarily waking up fully. It’s far more common than most people realise. A 2019 analysis in The Lancet Respiratory Medicine (Benjafield et al.) estimated that about 936 million adults aged 30–69 worldwide have mild to severe sleep apnoea, and about 425 million have moderate to severe sleep apnoea. Loud snoring, gasping during the night, morning headaches and feeling unrefreshed after a full night are signs worth raising with a doctor.
For more on how sleep affects long-term health, see How Much Sleep Actually Predicts a Longer Life?
2. Time Your Caffeine So It Doesn’t Cost You Tomorrow’s Energy
Caffeine works for alertness, which is why people rely on it. The catch is that it lasts longer than it feels. In a 2013 study in the Journal of Clinical Sleep Medicine, Christopher Drake and colleagues at the Henry Ford Sleep Disorders and Research Center gave 12 healthy sleepers 400 mg of caffeine (about 2–3 cups of coffee) at bedtime, 3 hours before bed, or 6 hours before bed. All three timings significantly disrupted sleep. Even the dose taken six hours before bed cut objectively measured sleep by more than an hour, and participants generally didn’t notice that their sleep had been disrupted.
This sets up a familiar cycle: an afternoon coffee leads to worse sleep, which leads to a more tired morning, which leads to more coffee. A practical rule from this study is to stop caffeine at least six hours before your usual bedtime, and earlier if you’re sensitive to it.
For half-life figures, tolerance and withdrawal, and how a coffee-nap works, see our guide to caffeine timing and energy.
3. Move More, and Start Gently
Exercising when you’re tired sounds backwards, but the research supports it, especially at low intensity. In a University of Georgia trial published in Psychotherapy and Psychosomatics in 2008, Tim Puetz, Patrick O’Connor and colleagues recruited 36 sedentary adults who reported persistent fatigue. For six weeks, one group did 20 minutes of moderate-intensity aerobic exercise three times a week, one group did the same amount at low intensity, and a control group didn’t exercise.
Both exercise groups had about a 20% increase in energy compared with the control group. The low-intensity group had the larger drop in fatigue, 65% versus 49% for the moderate group. O’Connor suggested that moderate-intensity exercise may be too much for people who are already fatigued. It was a small trial, but the takeaway is simple: if you’re tired, an easy 20-minute walk is a reasonable place to start. You don’t need a hard workout.
For the larger body of evidence behind this, and how to pace exercise when you’re already worn out, see our guide to exercise when you’re exhausted.
4. Drink Enough Water
Even mild dehydration can affect how you feel. In a 2012 study in The Journal of Nutrition, Lawrence Armstrong’s team at the University of Connecticut tested 25 healthy young women. A fluid loss of about 1.36% of body mass, which is well below the level most people would notice as thirst-driven dehydration, lowered mood and concentration, made tasks feel harder, and brought on headaches and fatigue. Their mental performance on cognitive tests largely held up, but they felt worse.
You don’t need to force down a set number of litres. Drink regularly through the day, more in hot weather and around exercise, and check that your urine is pale.
For official intake figures, where the “eight glasses” rule came from, and why thirst becomes less reliable with age, see our guide to dehydration and tiredness.
5. Check Your Iron, Even If You’re Not Anaemic
Iron deficiency anaemia is a well-known cause of fatigue, but low iron stores can matter before anaemia develops. In a randomised controlled trial published in the CMAJ in 2012 (Vaucher et al.), 198 menstruating women aged 18–53 with unexplained fatigue, low ferritin (under 50 μg/L) and normal haemoglobin took either 80 mg of elemental iron a day or a placebo for 12 weeks. Fatigue scores fell by 47.7% in the iron group and 28.8% in the placebo group, a meaningful extra benefit. Quality of life, depression and anxiety didn’t differ between the groups.
For the full picture on testing, the new 2026 ferritin cut-offs and how to ask your doctor about it, see our guide to low ferritin without anaemia.
Don’t start iron supplements on a guess, because too much iron is harmful. If you menstruate, eat little red meat, or have heavy periods and ongoing tiredness, ask your doctor about a ferritin test. For more on low ferritin’s other effects, see Iron Deficiency and Hair Fall.
6. Eat for Steady Energy
The research on specific “energy foods” is much weaker than the marketing. What’s more defensible is avoiding the things that reliably make people feel worse: skipping meals and then overeating, very large refined-carbohydrate meals that leave you sluggish afterwards, and relying on sugary drinks for a quick lift. Regular meals built around protein, fibre-rich carbohydrates (whole grains, legumes, vegetables, fruit) and some healthy fat are a sensible default. They also cover the nutrients whose deficiency causes fatigue, such as iron and B12.
If your energy reliably crashes after lunch, see our guide to the afternoon slump: the dip is mostly driven by your body clock, and there are a few things that reliably take the edge off it.
7. Manage Stress, Alcohol and Smoking
Stress is on the NHS’s list of common causes of tiredness, and anyone who has had a stressful month knows why: it disrupts sleep and wears you out during the day. Walks, time outdoors, exercise and talking to someone are reasonable first steps. If low mood or anxiety goes on for weeks, that’s a reason to see a doctor, since depression is also a common cause of fatigue.
Alcohol can make you fall asleep faster, but it tends to fragment sleep later in the night, so a few evening drinks can leave you more tired the next day. Smoking harms nearly every system that supports energy, from your lungs to your circulation. Quitting is one of the best things you can do for long-term health.
8. Stay Connected
Social connection doesn’t show up on a blood test, but loneliness is linked to worse sleep and worse health over time. Regular contact with people you like is one of the easier habits to protect. We cover the evidence in Loneliness, Social Connection and Longevity.
A Simple Plan to Start This Week
- Set a consistent bedtime that allows 7+ hours of sleep.
- Stop caffeine at least 6 hours before bed.
- Take a 20-minute easy walk at least three days this week.
- Keep water within reach and aim for pale urine.
- Eat regular meals instead of grazing on sugar.
- If you’ve been tired for weeks with no clear reason, book a doctor’s appointment and ask about blood tests (including ferritin).
Frequently Asked Questions
What is the fastest natural way to boost energy?
For a short-term lift, a brisk walk, a glass of water if you haven’t been drinking, and some daylight tend to help. Over the longer term, the habits with the best evidence are consistent sleep of 7+ hours, regular low-intensity exercise, and not letting caffeine eat into your sleep.
Why am I always tired even though I sleep enough?
Common reasons include poor sleep quality (for example, undiagnosed sleep apnoea), stress or depression, low iron, thyroid problems and diabetes. If it lasts more than a few weeks, see a doctor, who may order blood tests.
Does exercise really give you more energy?
Yes, in trials. In one six-week study of sedentary, fatigued adults, 20 minutes of low-intensity exercise three times a week cut fatigue by 65% and increased energy by about 20% compared with not exercising.
How late can I drink coffee without hurting my sleep?
In a 2013 sleep lab study, 400 mg of caffeine taken six hours before bed still reduced sleep by more than an hour. Stopping at least six hours before bedtime is a reasonable rule, and earlier is better if you’re sensitive to caffeine.
Can low iron cause tiredness without anaemia?
It can. In a randomised trial of fatigued women with low ferritin but normal haemoglobin, iron supplements reduced fatigue more than placebo. Get tested before supplementing, because excess iron is harmful.
