Why we need Sleep

This page explains why we need sleep, what happens when we do not get enough, the evidence for self help strategies and advice on which over the counter supplements help. It provides the answers for commonly asked questions concerning over 20 million people in the UK everyday:

  • How to go to sleep fast
  • How to get more deep sleep
  • Why can’t I sleep at night even when i’m tired

How much sleep do I need: We need around 7 hours of sleep to avoid daytime fatigue but up to 30% of the population regularly get less than 6 hours/night. Following a serious illnesses insomnia effects up to 70%.

What is REM sleep: Rapid Eye Movement sleep is sleep is characterised  quick eye movement, altered breathing and enhanced brain activity. The balance of REM and deep sleep is important for memory consolidation, emotional processing, brain development and dreaming.

Why do we need sleep:  Sleep slows the cell cycle which helps DNA repair, reboots energy stores and clears out toxins which have built up over the day.  Chronically poor sleep adversely effects gut health, impairs immune function, interferes with  melatonin release and hence interferes with a normal circadian rhythm. In the short term, a poor night’s sleep causes:

  • Fatigue
  • Memory loss and poor concentration
  • Irritability and relationship issues
  • Demotivation to exercise live healthily

In the long term, it contributes to chronic disease:

  • Obesity and Diabetes
  • Poor gut health
  • Heart disease and high blood pressure
  • Parkinson’s disease and dementia.

In addition, chronic insomnia and occupations such as night shift workers, are classed as risk factors for cancer. A study breast cancer survivors found that insomniacs had a 50%  worse cure rate but interestingly woman who regularly slept more than 9 hours a night were also more likely to relapse – probably due to disruption in circadian rhythm by sleeping too long.  Other factors that disturb sleep or disrupt the circadian rhythm have also been linked to an increased cancer risk such as eating late at night and skipping breakfast.

How to sleep better

The first step in managing insomnia  is to identify, and hopefully treat, conditions which cause discomfort and wakefulness at night such as anxiety, depression, pain, joint discomfort, restless legs, sleep apnoea and obesity, passing water at night, indigestion and hot flushes (night sweats).

Prescription medications such as hypnotics and Z-drugs which enhance the neuro-inhibitor Gamma-aminobutyric acid (GABA) are useful in the short term such after an emotional trauma or in the days after chemotherapy to counterbalance steroid wakefulness. Many doctors are cautions in prescribing them for long term use as they simply mask the symptoms without treating the underlying cause and studies have linked chronic use with dementia. These tablets also become less effective over time, meaning users often wake up in the early hours, unable to get back to sleep. Also these drugs reduce the amount of Rapid Eye Movement (REM) sleep. REM sleep plays a role in memory consolidation, emotional processing, brain development, and dreaming.

Watch this 20 minute presentation
“The evidence for lifestyle and nutritional strategies to improve sleep”
British Society of Lifestyle Medicine 2023

Lifestyle and dietary strategies to improve sleep

Sleep hygiene advice  provide tips on how to fix sleep schedule with practical strategies such as blackout curtains the bedroom, avoiding blue light, weighted blankets or avoiding stimulating electronics before bed, avoiding eating late at night – click here for the latest sleep hygiene rules. 

Exercise: The benefits of regular exercise were summarised in  6 RCT in which participants randomised to  moderate to strenuous exercise programmes had better sleep latency and better quality of life. Exercise helps to regulate the circadian rhythm, but for the best effect, for most people, it is better to exercise in the morning rather than very late in the evening. The other advantage of exercising in the daylight is to improve vitamin D levels as studies have also linked low vitamin D levels with insomnia.

Dietary factors: Avoiding caffeine and other stimulants from late afternoon is obvious but other, less well-known, habits include avoiding food late at night and eating breakfast which helps regulation of circadian rhythm. A correlation between processes sugar and poor sleep patterns was identified in number of studies including one involving 100 students using food frequency and sleep quality questionnaires in the weeks leading up to their exams.

Improve gut health: Poor gut health has been linked to insomnia in several studies so ensuring adequate pre and pro biotic rich foods in the diet would be sensible. As well as dietary measures to improve gut health, one double blind RCT reported that participants randomised to a Lactobacillus probiotic had significant improved sleep maintenance plus less day time fatigue compared to placebo.

Prebiotic foods include legumes, mushroom and chicory. Probiotic bacteria can be found in kefir, kimchi and sauerkraut (read more) or a good quality probiotic supplement such as YourGutplus+ which has lactobacillus combined with vitamin D and inulin.

Phytochemical rich foods: These gifts from nature provide the colour, odour and taste of many heathy foods such as vegetables, herbs, fruits and spices. They influence several mechanisms which interfere with a restful night. For instance, the phytochemicals resveratrol and apigenin found in polygonum cuspitadum root, grapes and chamomile have a synergistic calming, rather than sedating, effects which can reduce stress, improve mood and helping to reduce negative, wakeful thoughts at night. Curcuminoid in turmeric have anti-inflammatory and other positive effects on joints, helping to improve comfort at night amoung people with arthritis. Citrus bioflavonoids, resveratrol and quercetin in pomegranate help naturally enhance melatonin and restore the circadian rhythm get back . These foods, even if concentrated have a high safety profile.

Phytochemical rich supplements, if well made, are a convenient why to boost intake to levels well above eating the whole foods themselves. Boosting the intake of phytochemical within nutritional supplement to levels well above that achieved from whole foods themselves.  They are also very healthy and can play a remarkable role in preventing a wide range of chronic diseases and even improving nails as well as improving sleep quality. The largest group of naturally-occurring polyphenols are the flavonoids, including apigenin.

phytonight plusPhytonightplus+ has some of the best scientific evidence for improving sleep and reducing day time fatigue. This data emerged from a RCT involving participants suffering from long covid who commonly report insomnia, fatigue low mood. The intervention gave a combination of lactobacillus probiotics and a blend of concentrated whole foods rich foods which rich in the phytochemicals ellagic Acid, quercetin and EGCG in Pomegranate, curcuminoids in Turmeric, Apigenin in chamomile and citrus sinensis, hesperetin (from Pomegranate, Citrus Sinensis fruit) and resveratrol (from polygonum cuspidatum root). These foods do not effect GABA levels or cause direct sedation so have no hangover or additive effects but work in synergy to:

  • Improve mood and relax the mind and body
  • Support gut health via their prebiotic properties,
  • Ease joint discomfort via their anti-inflammatory properties
  • Prepare the body for sleep by stimulating melatonin production
  • Promotion of a regular circadian rhythm

The results published in 2022 showed a significant improvement in sleep, day time fatigue and other symptoms. The providers of the supplements for the trial have subsequently made the product available for the public over the counter (OTC).

Do melatonin supplements help sleep: Melatonin which is available OTC in some countries and can be prescribed in the UK by a doctor. It’s has been evaluated in over 35 RCT. Some of these showed some significant benefits for the short term but benefits for longer term use were not significant and many authors concluded that dietary strategies to naturally improve intrinsic melatonin levels would be better, certainly in the longer term.

Antihistamines such diphenhydramine in Benadryl and Doxylamine in Unisom can be bought OTC for hay fever or other allergies and can induce drowsiness which can aide sleep.  Side effects include daytime drowsiness, dry mouth, constipation and urinary retention. There is evidence that they can help for two to three nights at a time but tolerance to the sedative effects of antihistamines can develop quickly. As a result, the longer you take them, the less likely help. In older adults, confusion, hallucinations, constipation, nausea, impaired sweating, urinary retention, glaucoma and  tachycardia. In the longer term, Recent studies have shown that anticholinergics might increase the risk of cognitive decline.

Valerian plant extracts have been marketed for sleep problems in products such as Kalms. A number of RCT have been conducted summarised in two larger meta-analysies. About half reported a statistically significant benefit but most had publication bias and methological issues.

Chamomile has been used to treat sleep problems for years  as it helps reduce anxiety and improve sleep quality. Chamomile is generally regarded as safe when used as a tea or taken orally. A cup of chamomile tea does not have sufficient quantities which is why trials of more concentrated extracts, are more convincing for the benefits for sleep.  Apigenin within chamomile does not affect GABA receptors so less likely to cause sedation but instead improves mood so prepares the mind for sleep it also works better in synergy with other herbs which explains the beneficial effects of phytonight in the long covid trial.

Ashwagandha, an Indian medicinal plant that has been used for centuries to treat insomnia. It effects GABA receptors, so like valerian, can cause hangover effects in some people.

Does magnesium help you sleep: One small randomised trial of 46 elderly participants showed that supplementation of magnesium (mg) appeared to improve subjective measures of insomnia and likewise, insomnia objective measures such as concentration of serum renin, melatonin, and serum cortisol, in elderly people. A systemic review of 9 other RCT’s reported an uncertain association between magnesium supplementation and sleep disorders and concluded that futher more robust trials are needed. Interestingly, in a laboratory study  mg deficiency was associated with low levels of melatonin  which was corrected with mg supplementation but no improvement in melatonin if mg levels were normal, to start with. It is most likely that mg only helps if a person is deficient but not if levels are normal. Despite this lack of evidence of benefit for people wit normal levels of mg it is very popular OTC remedy  would make sense to take a sensible mineral supplement which includes good but not excess levels of Magnesium – read more

In conclusion, insomnia is very common and under emphasised in the population and certainly after illness.  There are plently of lifestyle and nutritional strategies which can help but those which don’t induce sedation such as phytonight+ have major long term advantages

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