Episode 76 – How to Improve Sleep with Nutrition

Key Topics Covered

Bi-directional relationship – Poor sleep can lead to poor nutrition choices, changes in appetite and cravings etc  


  • Caffeine obviously impacts sleep. 
  • Half-life of caffeine is 5 hours. But this can range from 1.5-9 hours.  
  • This means that for the average person, if you have a lot caffeine even 8 hours before going to bed, it is likely to reduce sleep quality or quantity in some way.  
  • Some people metabolise it a lot quicker than others though.  

Carbohydrate Intake and Timing 

  • Research indicates that having a high carbohydrate meal or snack 1-4 hours before bed can help reduce the amount of time it takes to get to sleep, while improving the amount of REM sleep. 
  • The impact is not huge though. It looks to be about a 10% improvement. 
  • BUT There is not much research on actual low-carb diets though, so it is hard to make fair comparisons.  
    • AND Time-restricted eating patterns do not seem to reduce sleep quality or quantity.  
  • Overall it probably doesn’t matter too much and if you have other goals that may require a reduced calorie/carb intake, probably not worth sacrificing that for this 
  • What likely matters more if that you aren’t too hungry when trying to sleep  

Tart Cherry Juice 

  • Tart cherry juice is the first “hack” I really have for improving sleep.  
  • It also doubles as that carbohydrate snack ~1-2 hours before bed too. 
  • Tart cherry juice increases melatonin and tryptophan production in the body. 
  • There is a study showing that tart cherry juice before bed increased sleep duration in those with insomnia by 85 minutes on average.  
  • That probably overplays how good tart cherry juice is, but it is still promising. 
  • We know that direct melatonin supplementation helps, but is not that impactful e.g. the average improvement in sleep duration is ~6 minutes. 

Being Overly Full/Hungry 

  • Going to bed excessively full reduces sleep quality and duration. Particularly for those who experience symptoms like reflux. 
  • Going to bed hungry also causes issues. 
  • Being in a calorie deficit for an extended period of time, or getting excessively lean also impacts sleep. Bodybuilders in late stages of comp prep are commonly known to struggle getting to sleep. 

Fibre, Saturated fat and Sugar 

  • Higher fibre intakes and lower saturated fat and sugar intakes have been linked with improved sleep. 
  • These things are also proxy measures for dietary quality though. People who do those things likely have better overall diets. 
  • One study compared a high saturated fat meal to a lower saturated fat meal and found the lower one led to people falling asleep 15 minutes quicker. So although a lot of the benefits would likely be chronic, there still might be some acute ones too.  

Stress Management Stuff 

  • Supplements to help with stress includine L-theanine + ashwagnadha 
  • Both of these supplements have research showing they help with sleep – but I would wager that it is more to do with decreasing anxiety and stress than anything else 
  • One study on people taking ashwagandah for 6 weeks had them self-report sleeping 72% better than they did at baseline. The placebo group showed a 29% improvement. 
  • There is not much direct research on L-Theanine and sleep. Anecdotally a lot of people who experience stress find it helps.
    • And the one study I am aware of involved children with ADHD and it showed improvement in sleep. So it is a speculative leap, but it makes sense that it can help. 


  • The mechanism makes sense. Magnesium binds to GABA receptors. GABA helps your brain wind down. 
  • Magnesium deficiency seems to reduce sleep. 
  • Magnesium supplementation on average helps those with insomnia. 
  • Without insomnia the research is less promising. Anecdotally a lot of people report improvements. But it is always worth factoring in placebo too e.g. like in the ashwagndha study how placebo led to a 29% improvement. It is hard to self-identify improvements in this area. 
  • Most people have a sub-optimal intakes of magnesium. Supplementing is likely not to be detrimental, if used in normal amounts, and might help. 
  • Would people get benefits from supplementing if they have higher magnesium intakes through food? It is hard to say. 

Relevant Links/ Resources

Studies Mentioned:

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