Refeeds & Diet Breaks: Do They Really Work?
Intro
About 10 years ago, was the first time I heard the term “refeed day.” I remember reading an article while dieting myself in a hard deficit. The article said that a “refeed day” would help to speed up your metabolism and allow you to lose weight faster. All while increasing your calories one day a week. It sounded magical. Imagine being on a hard calorie deficit for 10 weeks and being told if I wanted to be leaner, all I had to do was increase my calories up to maintenance one day a week. How good! However, when things sound too good to be true, they generally are. Over the last decade so much more education has come out on the topic so let’s break it down.
What is a refeed day?
A refeed day involves a short term calorie increase. The goal is to take you out of a calorie deficit and up to your TDEE aka maintenance calories. If your calories are at 2000 in a deficit and your TDEE is 2500 calories a day, you would increase calories immediately to 2500 for 1-2 days.
What is a diet break?
A diet break is almost identical to a refeed day. The primary difference is purely the duration. A diet break will generally be in reference to a 1-2 week period of increasing calories out of a deficit and those weeks spent at your maintenance calories.
Both have the same goal: increase calories immediately out of a calorie deficit and up to your maintenance.
Duration wise, refeed 1-2 days. Diet break generally 1-2 weeks
Negative metabolic adaptations rundown
To then understand why we would use both options, we first then need to understand metabolic adaptations. When you diet to lose body fat. Fat loss is obviously the primary goal. However, fat loss then leads to changes from the body in response to you losing weight.
Common negative metabolic adaptations include:
– Increased ghrelin – hunger hormone rises
– Decreased leptin – satiety hormone lowers
– Increased muscle protein breakdown
– Decreased libido
– Decreased energy and sleep
– Decreased NEAT – non exercise activity thermogenesis
– Metabolic rate lowers due to weighing less and NEAT levels decreasing
These are all very normal responses to dieting. Generally speaking, the more weight you lose, the more these will kick in and increase. This is normal.
This is why achieving a very lean physique becomes increasingly difficult the longer you diet.
Benefits of refeeds and diet breaks
The idea of a refeed is to minimise the rigours of dieting short term. The longer diet break aims to stop or at least lessen, the onset of negative metabolic adaptations. The best way to decrease the negative adaptations will generally come from gaining weight. Not what we want in a deficit with the goal of fat loss. Or spending some time out of a deficit, which is more ideal when dieting for fat loss.
How to set calories for refeeds and diet breaks
A simple way to increase calories for your refeed/diet break is to recalculate your new TDEE off of your current body weight. From there, calculate the difference in your current calories and calories for your TDEE. Let’s say it is a 500 calorie increase. Then, all you need to do is increase 500 calories. The most simple way I do this is by increasing carbohydrates. A 500 cal increase will mean I will increase my client’s carbohydrates by 125g for that short period. Protein and fats stay at the same level.
Are they effective?
Remember at the start when I said it was originally seen as this magic metabolism booster? Well not so much. Think of it like this:
If you have 10kg to lose. The more days in a calorie deficit, the faster you will lose weight. If you spend 10 weeks straight in a calorie deficit. You will lose faster than someone on the same calories who every 3 weeks spends 1 week up to their TDEE on a diet break.
Because the person diet breaking for 3 of those 10 weeks, will spend 3 less weeks in a calorie deficit. Fat loss is slower as less time is spent in a deficit.
However, this does not mean that diet breaks do not have their place.
Increasing calories short term can very much help the mental rigours of dieting. Having a mental break from low calories can make a person feel rejuvenated when coming back down to a calorie deficit. Remember, a person who is consistently compliant, will achieve better results than someone who has 1 good day and 1 bad day. A diet break or even 1 day of calories up can aid in compliance for an individual on their low cal days.
Which is superior?
In the past I would use the term that a 1-2 day refeed is for psychological benefits while a diet break is for both psychological and physiological benefits. Meaning, that the research originally seemed to show that in order to lower some of the negative metabolic adaptations of dieting, such as hunger, satiety, libido and even increasing NEAT levels once more. The research seemed to show this approach worked. We needed more than just 1-2 days of elevated calories. 1-2 weeks appeared to be more ideal to help lose lots of the negative metabolic adaptations.
Therefore, to best counter the negative effects of fat loss, a diet break would be more optimal with 1-2 weeks of calories up. Whereas, a short refeed would be a more desirable choice for a lifter who is feeling mentally burned out from a calorie deficit. A 1-2 day increase of calories could be just what the doctor ordered when it came to helping a client manage adherence. Give the dieter a short break, then have them feel rejuvenated before quickly coming back to a deficit.
However, more recent research has further confused things once more with a diet break study showing potentially no real significance of diet breaking on things like hunger levels, satiety and improving metabolic rate. Not conclusive evidence yet, but potentially showing that even a 1-2 week diet break does not have the physiological benefits we once thought.
Do you need to use refeeds and diet breaks?
Since the research is not yet clear on the physiological benefits, it is hard to definitively say they are a must. It does not appear that having a break from dieting for 1-2 weeks will make fat loss easier when back in a deficit.
However, this does not mean there are no benefits to diet breaks.
For myself, someone who coaches a lot of high level clients who need to reach incredibly lean levels. This usually means 14-20 weeks of dieting time for my clients. To spend the entirety of that duration in a calorie deficit is extremely taxing both physically and mentally.
Strategically utilising high calorie days both short term, 1-2 days, and longer term, 5-14 days can be an effective strategy. Simply allowing a client to break up the rigours of a calorie deficit can help, both physically and mentally. However, you need to account for this time spent up out of a deficit in your time frame to achieve your goal body fat.
For instance, let’s say your goal is to lose 6kg. A standard rate of fat loss is 0.5kg a week, which will roughly mean, 12 weeks of a calorie deficit is needed for this goal. If you or your client personally enjoy diet breaks, then this is fine. But you need to account for this in your time frame.
For instance, a commonly used approach is 3 weeks in a deficit with a 1 week diet break.
To achieve 12 full weeks of a calorie deficit with 1 week diet breaks every 3 weeks, means the total duration required to achieve your 6kg of fat loss is no longer 12 weeks.
Rather the time period will now reach 15 weeks to account for those 3 weeks of calories up out of a deficit. There is nothing wrong with this at all. It is just important to understand if you have a specific time period you need to be ready for.
In summary, both refeeds and diet breaks are fantastic tools to help a client with adherence to their fat loss goals. The tool of having a short term break from dieting can be a strategic approach to achieving fat loss goals by minimising the mental hurdles of dieting. And at least potentially, managing the negative metabolic adaptations of dieting.
However, diet breaks and refeeds are simply not magic. They are just tools that you can use in your fat loss phase if you like them.
Yours in fitness,
Coach Mark Carroll
