- A team of doctors reviewed hundreds of sleep studies to find what non-drug fixes actually work
- CBT-I (a type of sleep therapy) outperforms sleeping pills — and the effects last longer
- Your sleep schedule matters more than your bedtime — keep wake times consistent every day
- Cannabis makes sleep worse over time, not better — even if it helps you drop off initially
- Diet matters: Mediterranean-style eating is linked to fewer sleep problems
About this review
In January 2026, a team of doctors from Cedars-Sinai Medical Center and UCLA published a detailed review of everything we know about improving sleep without medication. They looked at hundreds of studies covering sleep habits, body clock timing, therapy, exercise, food, alcohol, cannabis, and sleep trackers.
Their conclusion: the best sleep tools aren't in a pill bottle. They're in your daily habits. Here's what the evidence actually says.
The most important thing: your wake time
The single most effective thing you can do for your sleep is wake up at the same time every day — including weekends. Not the same bedtime. The same wake time.
Your body runs on a 24-hour internal clock. Every time you sleep in on a Saturday, you're giving yourself the equivalent of mild jet lag for the rest of the week. The review calls this "social jetlag" and links it to worse sleep, higher obesity risk, and lower mood — even when total sleep time looks fine.
The therapy that beats sleeping pills
If you have real insomnia — trouble falling asleep, staying asleep, or waking too early — the most effective treatment is not a drug. It's called CBT-I (Cognitive Behavioural Therapy for Insomnia).
CBT-I is a structured programme, usually six to eight sessions, that works by changing the habits and thoughts that keep you awake. It consistently outperforms sleeping medication in clinical trials — and crucially, the improvement lasts after the treatment ends. Medication stops working when you stop taking it. CBT-I doesn't.
You can access it through your GP, or via apps like Sleepio that deliver the same programme digitally.
Exercise — but timing matters
Regular exercise is one of the best things you can do for sleep quality. The review found it improves how long you sleep, how quickly you fall asleep, and how deep your sleep gets. It also helps with sleep apnoea by reducing the weight and tissue that can block airways during sleep.
The catch: intense exercise within about two hours of bedtime can actually delay sleep for some people — your core temperature rises and takes time to come back down. Morning or afternoon exercise is safest. Light stretching before bed is fine.
What you eat affects how you sleep
The link between food and sleep is real, but it's more about overall patterns than individual foods. The review found that people who follow a Mediterranean diet (vegetables, fish, olive oil, wholegrains, legumes) and those who eat low-glycaemic foods report fewer sleep problems. The likely reasons: less inflammation and more stable blood sugar through the night.
Eating heavy, high-sugar meals close to bedtime tends to disrupt sleep. Obesity is also directly linked to shorter, worse-quality sleep and dramatically increases the risk of sleep apnoea — another reason diet matters.
Alcohol, caffeine & cannabis
Alcohol makes you drowsy but wrecks the second half of your sleep. It suppresses REM (dream) sleep and causes fragmented, restless sleep in the early hours of the morning. Even one or two drinks measurably changes your sleep architecture.
Caffeine stays in your system for 5–7 hours. A coffee at 3pm still has half its strength at 9pm. The review recommends cutting off caffeine before midday if sleep is a priority.
Cannabis is the most surprising finding for many people. While it can help you fall asleep faster, it suppresses REM sleep — just like alcohol. Regular use creates tolerance, meaning you need more to get the same effect, and when you stop, sleep often gets worse before it gets better. The review is clear: cannabis is not a sustainable sleep solution.
Consistent wake time, CBT-I, morning exercise, Mediterranean diet, morning light exposure. These all have solid, repeated evidence behind them.
Alcohol, cannabis, late caffeine. All three hurt sleep quality even when they seem to help you fall asleep initially.
Wearables like Oura and Whoop are useful for spotting trends over weeks — not for stressing about individual nights. Obsessing over nightly data can actually worsen sleep anxiety.
The review doesn't say never use sleep medication — but it firmly places it as a last resort after behavioural changes have been tried.
The bottom line
This review, from some of the most respected sleep researchers in the US, lands in exactly the same place as our eight tip cards: the fundamentals work. Consistent timing, daylight, exercise, good food, and no late alcohol or caffeine will improve most people's sleep more reliably than any supplement or gadget.
If you've tried the basics and still struggle, CBT-I is the evidence-backed next step — not a higher melatonin dose or a stronger sleeping pill.
Jiyeon S, Oragun R, Dennis S, Elen G, Fariha H, Sherzai D, Roy A. Lifestyle and Behavioral Enhancements of Sleep: A Review. American Journal of Lifestyle Medicine. 2026 Jan 7. PMC12779539 →