We all know someone who constantly seems to be on a diet.
Whenever we see them, they’re on some kind of no-carb plan, following clean eating rules, or they’ve been sucked into a crazy detox cult.
Very occasionally, (and quite incredibly), they might be doing something that makes sense—like counting calories, tracking macros and eating in a deficit.
Regardless of what method they’re following though, one thing is consistent: They always look the same.
Figuring out why someone on a fad diet never changes isn’t too difficult; chances are they’re regularly binging and having huge cheat days. But what about the guy or girl who counts calories? Surely they should be losing body fat?
Perhaps they’re overdoing things on weekends or not tracking accurately. But then again, there are plenty out there who seem to be on point 95% of the time, yet forever dieting and not seeing results.
The answer to their issue could be that they’re not cycling their nutrition.
If your body didn’t hate dieting, you wouldn’t have the urge to overeat!
Your Body Hates Dieting
To lose body fat, you have to be in a calorie deficit. There are no two ways about it. As you will probably know from previous experience though, losing weight isn’t the only side effect caused by a calorie deficit. You can also experience:
- Higher levels of grehlin and lower levels of leptin 
- Loss of libido
- Reduced muscle mass
- Decrease in performance
- Lower metabolism [2-4]
Diet sensibly (i.e. eat in a small to a moderate deficit, with ample protein, carbs, and fat) and the negative consequences from dieting are massively diminished. Dieting still takes its toll though, especially if you’re concerned about maintaining muscle and strength.
So how do you ensure that you can diet long enough to hit your goal weight without falling into the trap of feeling like you’re forever in a deficit?
Enter Phasic Dieting
It might sound cool and sexy to boast that you lost 70 pounds of fat in one go, but this isn’t the smartest way to do things.
Your metabolic rate is a key determinant in how successful your fat loss phase is, and long, drawn out and aggressive diets slow your metabolism, creating a potential pitfall where losing weight gets harder the longer your diet drags on. Part of this metabolic slowing is due to a drop in body weight, but it’s also related to adaptive thermogenesis, where your body lowers its calorie expenditure at a greater rate than could be predicted by weight loss alone.
Because your metabolism will slow down over the course of your diet, it’s very, very unlikely that you will be able to lose 70 pounds of fat in one go (if that’s how much you have to lose) without cutting calories to “poverty macro” status or doing endless hours of cardio to keep yourself in a deficit.
Your body just won’t play ball.
If that weren’t bleak enough, consider the “set point theory.” This is the idea that your body has a certain weight or body fat level that it feels most comfortable at, and will always try to get back to no matter what you do . There’s a good chance that you will be fighting your body fat set point if you try and lose a large amount of weight in one long drawn out diet.
So what’s the dedicated dieter to do? Slash calories to reach the goal as quickly as possible? Attempt to beat down the body fat set point using poverty macros, excessive exercise, and sheer determination? Continue trying to “out diet” a struggling metabolism?
No way! There’s a solution to the dieter’s dilemma, and it’s called “phasic dieting.”
Phasic dieting is a nutrition strategy used by those seeking to lose body fat, preserve a healthy metabolism, and re-establish a new body fat set point. By breaking your diet into phases incorporating breaks or short periods of reverse dieting, you will get to your ideal physique with more muscle mass, while consuming more calories and doing less cardio.
There’s also research to support the efficacy of phasic dieting. A 2014 study from Trexler, Smith-Ryan, and Norton advised that athletes should approach weight loss in a stepwise, incremental fashion, including periods of reverse dieting to help mitigate any negative side effects. 
That’s why it’s so vital not to try and lose a large amount of body fat in one go, but to instead factor in phases for losing, maintaining, and even gaining a little bit of weight. Not only does this protect your metabolism, but it gives your body time to adapt to its new set point.
Slow and Steady Wins the Race
Smart dieters lose body fat gradually.
But the smartest dieters cycle their nutrition, just as any savvy powerlifter or bodybuilder cycles their training.
In the training world, if you go as hard as you can week after week without ever programming any rest days or recovery weeks in, you will likely end up injured and over-trained. Similarly, in the nutrition world, if you subject your body to a severe calorie restriction for months on end without ever programming any breaks or periods of reverse dieting in, you will run your metabolism into the ground!
So how might the process of nutrition cycling look? Consider the following situation.
Let’s say you estimate that you have 40 pounds to lose to get very lean. Rather than aiming to do this all in one go, you might aim to lose 20 pounds over the course of 16 to 20 weeks, then take a break.
This break would either involve starting a reverse diet and then entering a maintenance phase where you work on regaining some strength and muscle mass.
The length of the break will likely be about 12 to 18 weeks depending on how you feel during it, how you felt during the dieting phase beforehand, and what kind of timescale you’re on. You might also aim more toward the 18-week end of the range if you’re overly concerned about maintaining or building strength and muscle mass, and more toward the 12-week end if you’re not.
During this reverse and maintenance stage, your weight would probably remain stable or go up slightly. This isn’t taking you away from your goal though—by building some muscle and raising your calories, you’re putting yourself in a far stronger position to diet again by giving your metabolism a boost and getting some much needed energy back.
Let’s say that during your break your weight does rise by 5 pounds. you would then have 25 pounds to lose to get shredded. Your next phase would take care of 20 of those pounds, and take another 16 to 20 weeks. A short break or reverse would follow, where you gain 3 pounds, before a final assault on that last 8 pounds.
This whole process might take roughly 60 to 80 weeks, and in theory, you may have been able to lose the same amount of weight in less time. But if you would do that, you would likely have finished with:
- A lower calorie intake
- More cardio
- Less muscle mass
- More body fat
- Decreased quality of life and relationships through having to skip social occasions
- Less energy and motivation
Sure, you got there a bit sooner, but wouldn’t it have been more sensible to give yourself an extra few months and look better, feel better, and finish on higher calories by the end of the diet?
Fast weight loss is great, but it always comes at a cost—and that cost is a more severe diet that’s harder to stick to, as well as a drop in lean mass and metabolic rate. Phasic dieting, however, guarantees that you still lose the weight you want, but that you get there eating more food, with more muscle, and having more fun.
That’s a win in anyone’s book.