Snacks #010: How your sleep can affect metabolism & sabotage your diet

Let’s chat about the sneaky ways that lack of sleep can affect your metabolism & nutrition, and what you can do about it.

If you can be aware of how a lack of sleep changes your behaviour and metabolism, then you’ll be three steps ahead of yourself with preventing it and mitigating the damage.

Unfortunately, most people only focus on calories or macronutrients while trying to lose fat, and don’t realise that other lifestyle factors can affect their adiposity (level of fat) as well as how much muscle they retain when dieting.

The research:

This study by Nedeltcheva* showed that insufficient sleep across a 2 week diet reduced fat loss by 55% and increased loss of fat free body mass by 60%.

This is a crazy difference!!

And why exactly was lack of sleep so bad for fat loss? 

To summarise, the researchers found it to be a combination of these unwanted effects:

• Enhanced adaptation to calorie restriction
• Lowered metabolic rate to burn fewer calories
• Increased appetite
• A shift towards burning muscle instead of fat for energy

These results mean sleep might be just as crucial as macronutrient distribution for body composition outcomes during a diet.

The takeaway? 

Time to optimise your sleep! 

Wind down before bed, aim for around 8 hours and create an restful routine that you can stick to.

The biggest mistakes I see with sleep loss are:

1. Sacrificing sleep for Netflix
2. Regular weekend late nights
3. Having alcohol too close to bed
4. Making up for exercise in your morning sleeping hours
5. Exercising too close to bedtime (exercise increases core temperature and can make you feel wired)

Instead of doing these, it’s better to:

• Wind down before bed for 30-60 min without screens
• Keep your routine on the weekend. Try not to sleep too late or sleep in too long as this affects sleep hormones.
• Minimise alcohol before bedtime. Keep it a few hours away from sleep and stay hydrated.
• Prioritise your exercise during the week so you can do it at a suitable time
• Hold off caffeine after midday. Sorry... try decaf instead. Fun fact; caffeine is one of about 1000 chemical components in coffee, and removing caffeine does not affect the flavour.

I’ll leave you with a simple question;

Looking at these dot points, where could you optimise your sleep (and therefore, your nutrition)?