Can oily fish, cherries or milk help you sleep? Here’s what the evidence shows

Dec 21, 2021

4 min

Dr Duane Mellor


Almost one in five British people report they don’t get enough sleep each night. The problem is so bad that in total the UK public are losing around a night’s worth of shut-eye each week.


There are a lot of popular beliefs about foods and drinks helping people get a good night’s rest, but many of them are not based on scientific evidence. Here’s what we know.


Chemistry of food and sleep

Our diet has an influence upon sleep patterns by affecting the sleep hormone melatonin. For example, foods rich in the essential amino acid tryptophan are commonly cited as helping sleep, as tryptophan helps produce melatonin. Additionally, some vitamins and minerals may help sleep, such as vitamin D, magnesium and zinc.


Oily fish: Evidence suggests the more oily fish, such as salmon or herring, you eat the better you sleep. Oily fish contain healthy fats such as omega-3 oils which have been shown to improve sleep in children and are involved in serotonin release. Serotonin, a brain chemical linked to mood, also regulates the sleep-wake cycle which may also explain how eating oily fish can help.


Tart cherries: A number of studies have looked at consumption of tart cherries, usually in the form of a drink, and sleep. Evidence suggests that tart cherries improves sleep in older adults, probably due to their ability to increase melatonin levels. And tart cherries are also rich in nutrients, including magnesium, which also may improve your sleep.


Kiwi fruit: The evidence for kiwi fruit helping you sleep is mixed. One study suggested four weeks of kiwi fruit consumption improved multiple sleep measures, while another, admittedly in sufferers of insomnia, found no effect. Based on these findings it is not clear yet that eating kiwi fruit will benefit sleep for most people.


Oysters: In 1888 W F Nelsom wrote “He who sups on oysters is wont on that night to sleep placidly…”. There is some evidence to back up this statement, with zinc-rich foods, including oysters, being reported to benefit sleep. However, on balance eating oysters before bedtime is unlikely to be beneficial to your night’s sleep.


Alcohol and other drinks

Alcohol causes brain activity to slow down and has sedative effects that can induce feelings of relaxation and sleepiness> But consuming alcohol is actually linked to poor sleep quality and duration. Although drinking alcohol may cause more rapid sleep onset, this can affect the different stages of sleep, decreasing overall sleep quality. If you want a good night’s sleep, avoiding alcohol is sound advice. But are there any non-alcoholic drinks that might help?


Warm milk: Research conducted in the 1970s suggested that a glass of warm milk before bed could improve sleep quality. This research was performed in a very small group however, and little research has been done since. Drinking milk does increase melatonin levels which could help. But there isn’t enough evidence to support the claim that a glass of warm milk definitely makes you nod off.


Bone broth: Bone broth commonly crops up in online articles as a food that can aid sleep. This may be due its high content of the amino acid glycine. Glycine has been shown to improve sleep in rodents and humans, possibly by lowering body temperature. There are however no studies specifically looking at bone broth consumption and sleep.


Herbal teas: The range of herbal teas aimed at the sleep market has grown and grown. Evidence for valerian, a common ingredient, to aid sleep is inconclusive. Decaffeinated green tea has been reported to improve sleep quality, which might be linked to the relaxing qualities of L-theanine, an amino acid it contains, but in general, avoiding caffeinated teas is a wise choice. If you like herbal teas, then they can be part of a relaxing pre-bedtime routine – but they are unlikely to improve your sleep quality.


A bedtime routine

Having a bedroom environment and daily routines that promote consistent, uninterrupted sleep are important. These include keeping to the same time to head off to bed, making your bedroom free of disruptions and having a relaxing pre-sleep routine. But many of the foods that have claimed benefits for sleep have little or no evidence behind them, to the point there are no legally recognised health claims for food assisting sleep approved in the UK or Europe.


If any one of these things helps you to sleep well, there’s no reason to stop. But just remember the other basics of a good nights sleep too, including relaxing before bed and avoiding too much blue light from electronic devices.

Connect with:
Dr Duane Mellor

Dr Duane Mellor

Visiting Academic

Dr Mellor is an award-winning dietitian, science communicator, medical educator and researcher.

Food ScienceDieteticsDiabetesObesityNutrition

You might also like...

Check out some other posts from Aston University

7 min

Budget 25 – initial reactions related to personal financial wellbeing

As the director of the Aston Centre for Personal Financial Wellbeing, and a professor of taxation, I obviously take particular interest in the annual budget day as it sets a tone for much of the personal finance changes that are likely to occur in the near future. The lead up to this year’s budget had unprecedented levels of speculation with much of the press and commentators trying to get attention with ever more it seemed wilder guessing of what the chancellor might do – largely unhelpfully and worrying people and the markets unnecessarily. Almost all of this proved wide of the mark as the budget didn’t increase any of the main taxes at all, and where it might nudge National Insurance contributions (NICs) up for some, this won’t be for a few years and only in a small area (pension payments for employees) that won’t actually affect most people. Small and cautious steps to reform The reason for all this speculation of key changes needed was that everyone suspected there was a big hole in the national finances. This was shown not to be the case. In fact, predictions provided in the budget documents are we’d in fact be in budget surplus by the end of this parliament period even before the changes announced take effect. This was a surprise to many and meant the chancellor could actually focus on at least some small and cautious steps towards reforming how our tax, benefit and government spending systems work. What she proposed therefore is currently predicted will raise circa £26bn and give the government ‘head-room’ to cope with economic changes later rather than needed to fill a feared financial black hole now – good news all round! This meant what we actually got was lots of smaller changes with fewer ‘rabbit out of a hat’ big tax surprises than we have had in recent years – a welcome steadying trend I hope will continue. She also promised some short-term spending that can be paid for with a combination of extra borrowing now and with increased taxes later – again a trend of recent budgets. If these tax changes actually happen in the end, then it will be down to what happens between now and when these were proposed to commence – by no means a guarantee these will ever happen. Later budgets, or other rule changes in the future, could easily retract or counter them (all chancellors like to announce planned tax changes aren’t going to happen for obvious political gain reasons!). Income tax changes The largest share of the extra £26bn raised will come from extending the income tax thresholds for a further period – now to 2031. These have been fixed (at £12,570 for example for the point at which income tax starts to need to be paid on personal incomes) since at least 2023, some well before this. This matters, as, when wages rise due to inflation, people are not better off in reality (you get more income but things cost more), but may end up paying more tax than before as the thresholds haven’t increased with inflation to the same degree (what we call ‘fiscal drag’). As such, holding these thresholds fixed for longer will raise extra money for the government (predicted to be over £12bn a year in 2030-31 for example) – largely unnoticed as to many it doesn’t feel like the tax rise it clearly is. The threshold fixing extension announced today will mean that as many as 700,000 more people will start to pay some income tax when they wouldn’t currently, and up to 1 million more people will start to pay higher rates of tax than currently – all without being actually better off in real terms. Some call this stealth tax, but it feels very real when it starts to affect you if your total taxable incomes fall near these threshold levels. There were in total more than 70 other tax measure changes in this budget – a huge number and lots to get your head around. However, most of these will not affect most people and are relatively small in nature – targeted at making the tax system a little fairer (i.e. those on higher incomes, with more savings, dividends, receiving additional income from property they own etc – paying more taxes as a proportion of the total amount raised in tax from all sources). This is clearly welcome news (at least for those not being asked to pay this extra) in the current climate. The biggest changes for financial wellbeing As a research centre focusing on individual and family financial wellbeing, what do we think are the specifics announcements made that are most likely to affect people – several headline announcements are worth highlighting: -  1. The removal of the two-child limit on benefit eligibility is obviously a key headline – long touted as a key reason larger families are much more likely to be in poverty than smaller families. This is a key change that many Labour MPs wanted to see happen and the chancellor has delivered on it. This is very welcome news – although it won’t start to affect these families until after April 2026 to give time to bring these measures into place – but then predicted to lift 450,000 children out of poverty. 2. As part of making the tax system more progressive, a brand-new tax was announced on very expensive houses in England – to be snappily called the High Value Council Tax Surcharge (or HVCTS) – although expect it to be called the ‘mansion tax’ by everyone! The UK’s main local tax (council tax) isn’t going to be reformed as such in this change – despite being the target of much speculation that it is just too regressive to leave unreformed any longer after we haven’t revalued houses in most of the UK since 1991. This will instead be an additional tax, commencing in April 28, on those whose properties are valued (now) at £2m or more – with higher rates rising to those with properties over £5m. Clearly this will affect relatively few in most of the UK (only expected to affect 1% of properties nationally), but will affect some and will raise extra revenues (expected to raise circa £400m+ a year) to directly support provision of local services – much needed in many parts of the UK. 3. New taxes on electric cars – given fuel duty is not paid by those who drive electric cars (as they don’t buy petrol or diesel) there have been calls for new taxes to be charged to electric car drivers. While these cars may be better for the environment when driven, they continue to wear roads and contribute to congestion. The government is proposing a per mile charge from April 28 (to be called the Electric Vehicle Excise Duty or eVHD) for these vehicles which will be painful for electric car divers – not least as this cost as not known when purchase decisions were made. No-one likes a tax charged on something you have already made the decision to buy so expect this to be unpopular. It is proposed currently to cost EV drivers around £20/month – about half the rate of fuel duty on average – and expected to raise circa £2bn a year by 2030-31. I expect this tax will become more nuanced in future perhaps as technology enables perhaps different charges to be applied to use of congested city roads compared to open rural driving perhaps - we will see.  4. National Insurance deductibility for pension contributions via salary sacrifice schemes operated by many employers for their employees is to be capped at £2,000 (although only from April 29 – so no immediate effect). This now very widely used approach to making pension contributions if you are an employee that in effect avoids you having to pay NIC on this income going into your pension. For those with larger pension contributions the bit that can be made before NIC is due on the extra this will be capped in the future to £2,000 per year – again affecting those who receive higher pension contributions most and affecting those at the bottom of the income spectrum, little if at all (74% of employees are predicted not to be affected). Is this a breach of the Labour manifesto promises not to increase the main taxes? For some it certainly seems that way. What didn’t happen? There are many smaller measures to explore, or ones that are not coming into effect for the next year or more that might have been missed from the news headlines but that will almost certainly affect lots of people. To name just a few (including highlighting several things NOT going to happen – which will obvious not save people money per se, but help by not costing them more): - above inflation increases to national minimum (‘living’) wage for all age groups from April 2026 (+4.1% for those over 21)– although still not raising this to ‘real living wage’ levels. further extension of holding off on the 5p/litre fuel duty rise not increasing prescription charges (staying at £9.90 for the next year) confirming state pension rises by 4.8% from next April (worth £575/year) confirming £150 winter fuel payments again this winter to over 6 million homes freezing regulated rail fares – preventing the usual annual increases from January (the first time this has happened in 30 years) extending the government’s Help to Save scheme to more benefit recipients than previously No immediate impact for most Overall, this is therefore probably a welcome budget for many, those on lower incomes will likely get the most from these measures, if all are applied as proposed, but most won’t see much of an immediate impact immediately – and with the largest benefit likely to all on larger families in receipt of benefits from next April.

2 min

How mitochondria shape brain health from childhood to old age

From the first spark of neural development to the challenges of ageing, Dr Lissette Sánchez Aranguren is uncovering how the cell’s powerhouses — mitochondria — hold the key to a healthy brain across the human lifespan. Her pioneering research at Aston University explores how these microscopic energy generators safeguard the brain’s communication network and how their dysfunction may underlie conditions such as dementia, stroke, and neurodevelopmental disorders. Mapping the brain’s energy defence system Dr Sánchez Aranguren’s work focuses on the partnership between brain cells and the blood vessels that nourish them — a relationship maintained by the blood–brain barrier. When mitochondria fail, that protective interface can weaken, allowing harmful molecules to penetrate and trigger inflammation or cell loss. Her team’s studies show that mitochondrial malfunction disrupts the dialogue between neurons and vascular cells, an imbalance seen both in the developing and ageing brain. To counter this, she and her collaborators have engineered a mitochondria-targeted liposome, a nanoscale “bubble” that delivers restorative molecules directly where they are needed most. By re-balancing cellular energy and communication, this innovation could one day reduce brain injury or slow neurodegenerative decline. From heart cells to the human mind Originally trained in cardiovascular science, Dr Sánchez Aranguren became fascinated by how mitochondria regulate energy and stress in blood-vessel cells — insights that ultimately led her toward neuroscience. View her profile here “Mitochondria do much more than produce energy. They send signals that determine how cells communicate and survive.” That realisation inspired her to trace mitochondrial signalling across the continuum of life — linking early brain development to later-life vulnerability. Her research now bridges traditionally separate fields of developmental biology, vascular physiology, and ageing neuroscience, helping identify shared molecular pathways that influence lifelong brain resilience. Global collaboration for a healthier brain Her work thrives on multidisciplinary and international partnerships. At  Aston, she collaborates with scientists from Coventry University, Queen’s University Belfast, and the University of Lincoln, alongside research partners in the Netherlands, Italy, Malaysia, and China. Together they integrate chemistry, biology, and computational modelling to understand mitochondrial function from molecule to organism — and translate discoveries into practical therapies. Towards mitochondria-targeted brain therapies The next frontier is refining these mitochondria-targeted nanocarriers to enhance precision and efficacy in preclinical models, while exploring how mitochondrial signals shape the brain’s vascular and neural architecture from infancy through adulthood. Dr Sánchez Aranguren envisions a future where protecting mitochondrial health becomes central to preventing brain disease, shifting medicine from managing symptoms to preserving the brain’s natural defence and repair systems. “If we can protect the cell’s own energy engines,” she says, “we can give the brain its best chance to stay healthy for life.”

2 min

From circular supply chains to global sustainability leadership: How Dr Luciano Batista is shaping the future of the circular economy

When it comes to transforming how organisations produce, consume, and reuse resources, Dr Luciano Batista, professor of operations management at Aston University, is a global pioneer. His research sits at the crossroads of innovation, digital transformation, and sustainability, tackling one of humanity’s most pressing challenges: our overconsumption of the planet’s resources. Reimagining the economy around renewal Dr Batista’s work focuses on circular supply chains —a model he helped establish at a time when 'closed-loop' systems dominated sustainability thinking. His early research laid the foundation for how businesses could move beyond recycling and linear take-make-dispose models, instead designing systems that reuse, restore, and regenerate.  View his profile here From theoretical frameworks to real-world applications, his studies—such as comparative analyses of circular systems implemented by Tetra Pak in China and Brazil—demonstrate the measurable economic and environmental benefits of circularity in action. His 2022 Emerald Literati Award-winning paper introduced a methodology for mapping sustainable alternatives in food supply chains, earning international recognition for its real-world impact. A global voice for industrial symbiosis and circular innovation The influence of Dr Batista’s work reaches far beyond academia. He has advised the European Commission’s Circular Cities and Regions Initiative (CCRI) and contributed insights to policymakers through the UK All-Party Parliamentary Manufacturing Group. His expertise continues to inform national and regional strategies for sustainable production and industrial symbiosis —where one company’s waste becomes another’s resource. Today, he extends that impact globally as a visiting professor at the Massachusetts Institute of Technology (MIT), conducting research at the MIT Center for Transportation & Logistics on circular supply chain innovations, supported by Aston University’s study-leave programme. He also mentors future leaders in sustainability as part of Cambridge University’s Institute for Sustainability Leadership (CISL). Driving the next wave of sustainable transformation Looking ahead, Dr Batista is spearheading collaborations through Aston’s Centre for Circular Economy & Advanced Sustainability (CEAS), working with the Energy & Bioproducts Research Institute (EBRI) and West Midlands Combined Authority (WMCA) on projects developing biochar-based clean energy systems for urban districts. He is also advancing the social dimension of the circular economy—ensuring that the move toward sustainable production is inclusive and equitable. His Symposium on the Socially Inclusive Circular Economy, held at the 2025 Academy of Management Conference, has sparked new international research partnerships with Monash University (Australia) and the Vienna University of Economics and Business. A vision for a regenerative future At the heart of Dr Batista’s work is a simple but urgent truth: humanity is consuming resources at a rate our planet cannot sustain. Through his research and global collaborations, he is helping organisations, policymakers, and communities move toward a future where growth and sustainability coexist. “The transition to a circular economy is not optional—it is essential,” says Dr Batista. “Our goal must be to redesign systems that allow people, businesses, and ecosystems to thrive together.”

View all posts