Written by Catherine Saxelby
on Wednesday, 04 August 2021.
Tagged: carbohydrates, fat, health, healthy eating, macronutrients, nutrition, protein, sleep
Good quality sleep is essential for good health as it impacts metabolic, emotional and cognitive processes. Given that sleep problems affect one in three adults and have been linked to the leading causes of death such as cancer and heart disease, it seems that the need to improve sleep is a ‘no-brainer’.
We have long known that your sleep is affected by your food intake. Likewise, sleep affects your dietary intake and nutrition, and short sleep has been linked to obesity. (See my post Getting a good night’s sleep in 9 ways. ) Because of the importance of this relationship, more and more researchers are looking at the effects of manipulating macronutrient intakes (proteins, fats, carbs) on sleep outcomes. Here’s a recent report.
This 2021 study is a systematic review and looks at the effects of macronutrients on sleep improvement, in order to provide dietary recommendations for better sleep.
A research study was included in this review if it:
A total of only 19 studies met the above criteria (note: this is not a lot). The 19 studies were organised into:
To understand the results of the review we need a quick overview of the four stages of sleep. The first three are categorized as non-REM (Rapid Eye Movement) Sleep and the fourth is REM sleep.
The review found that short sleep was associated with greater energy (kilojoule/Calorie) and fat intake “as well as increased snacking and inadequate micronutrient intake, particularly calcium, vitamin D, and magnesium”.
The results which most positively influenced Rapid Eye Movement (REM) sleep were observed for longer-term administration of higher carbohydrate diets. This means carbs ranging from 56 to 80 per cent of energy intake. So, for a standard 8,700 kJ (2200 Cal) diet, this translates to 280 to 350 grams of carbs a day (14 to 17 slices of bread).
However, higher carb diets also negatively influenced Non-REM sleep which led to overall neutral findings for sleep.
The higher protein diets, under conditions of energy restriction, for weight loss did improve sleep quality. Weight loss of any sort has long been linked to better sleep duration and quality but this can also interfere with any results.
Four out of the five studies changing the quantity of protein or carbs eaten while holding fat constant reported beneficial effects on sleep quality.
The study reported that it does not support the effects of short-term meal-based interventions, less than a night, on sleep outcomes. You can’t affect your sleep in just one night – you have to manipulate your overall diet for at least a couple of nights before you can see any sleep benefit at all.
The science is not yet ready to make public health recommendations. The researchers concluded that the sleep interventions were highly varied and shortcomings to all the methods were identified (small sample size, imprecision, gender imbalance, heterogeneity, high risk of bias). More work is required to fully understand how macronutrient intake affects sleep outcomes. However, for now, losing weight, it seems, can help you get higher quality sleep.
Don't miss a post. Sign up for Catherine's eNewsletter and get the latest Foodwatch news, product reviews, recipes and special offers direct to your inbox each month. It's free. Plus you'll receive Catherine's 26-page ebook "Cut the CRRAP - How to limit your intake of ultra-processed foods".
You can unsubscribe at any time and we never give your details to any third party.
Catherine Saxelby has the answers! She is an accredited nutritionist, blogger and award-winning author. Her award-winning book My Nutritionary will help you cut through the jargon. Do you know your MCTs from your LCTs? How about sterols from stanols? What’s the difference between glucose and dextrose? Or probiotics and prebiotics? What additive is number 330? How safe is acesulfame K? If you find yourself confused by food labels, grab your copy of Catherine Saxelby’s comprehensive guide My Nutritionary NOW!
© 2023 Foodwatch Australia. All rights reserved
Author photo by Kate Williams
Website by Joomstore eCommerce