There’s a general misconception that losing weight fast is not good for you, not sustainable and once you’re done with your diet you will put back on all the weight you lost or even more. So, fast weight loss is bad? It depends.
Is slow and steady weight loss a better approach? Again, it depends.
Both have advantages and disadvantages, but in the end, when we draw the bottom line we’ll see that one is better than the other. Read on to find out which and why.
But before we start debating let’s have a common understanding of fast and slow weight loss.
How fast is fast?
A weight loss rate higher than 2 pounds / 1 kg per week is considered fast, for most people.
How slow is slow?
A weight loss rate of less than 1 pound / 0.5-0.6 kg per week is considered slow, for most people.
The numbers above might vary for severely overweight people who tend to hold a lot of water weight and can see dramatic weight loss in the first stages. Also, for very lean individuals (less than 10% body fat for males and less than 20% body fat for females) it’s normal to experience a slightly lower weight loss rate.
Losing weight slow
This is an approach that is quite common and popular in many people in the fitness industry, because it is very unlikely to see any muscle mass loss when losing weight or more correctly said losing fat, at a slow rate.
Preserving lean mass when cutting is a big thing that everybody looks at because we all know than muscle mass is not something you get overnight, therefore you don’t want to lose any of it because of a poor diet. That’s pretty much the argument behind losing weight slow.
Advantage: Zero muscle mass loss during a slow weight loss program.
The main reason for muscle mass loss is an aggressive caloric deficit and a low protein diet. And because in a slow and steady fat loss program the caloric deficit is moderate it means you are able to fit plenty of protein easily and you are very less likely to lose any muscle mass by following such a diet.
That’s the good side of the story and the main advantage of why losing fat at a slower rate would be considered beneficial. However, losing weight slow has a bunch of drawbacks than, as you will see, can offset the advantages.
I identified 3 major disadvantages of slow weight loss which are outlined below, in no particular order.
Disadvantage #1: Exhaustion
Disadvantage #2: Metabolic slowdown
Disadvantage #3: Less time bulking
You probably guessed already that the disadvantages overpower the advantage and a slow weight loss diet plan is not an optimal one. Let’s see why in more depth.
Disadvantage #1 –Exhaustion & mood
Long term dieting and long term caloric restriction is exhausting and very taxing on you both mentally and physically. This is something that most nutritionists or diet plans never mention, and you will have to learn it the hard way.
The longer you stay in a negative energy balance the bigger the chances of going off track and ruining all the progress you made. Eating less than your body needs will lower leptin levels as well as other hormones which play an important role on making you feel happy and content. That’s why we feel cranky when we are hungry.
Imagine how it would be like to feel like this for months. There’s no way in hell anyone could stick to such a diet for so long. It will ruin your mood; it will ruin your workouts and your social life. That’s why you need to lose fat as fast as you can (in a smart way), but more on that later on. Let’s get to the next disadvantage of losing weight slow.
Disadvantage #2 – Metabolic slowdown
Metabolism will adapt to your calorie intake whenever you are losing weight fast or slow. It’s just how our body works trying to reach metabolic homeostasis. When we eat less, the body will slow down the energy consumption in an attempt to compensate for the caloric deficit.
The longer the deficit the more the metabolism slows down, hence the disadvantage of dieting for long periods of time. Once your metabolism catches up with the caloric deficit you put yourself to, you will have to increase the deficit and so forth and so on until you get to the point where you are eating ridiculously low amounts of food and you are still not losing any weight. This is what specialists call a “damaged metabolism”.
Eventually you will have to give up, maybe you will start binging because of all the stress you have been through and combined with a slowed down metabolism which will be overwhelmed by the increased amount of calories you will end up gaining more weight than before. You definitely don’t want this to happen.
That is why you need to take special attention to how your body in general and your metabolism in particular reacts to your diet. I have written a whole article on this topic which I recommend you to check out over here.
Disadvantage #3 – Less time bulking
From a muscle building point of view, a long caloric deficit (cutting) period is not optimal at all. As you may know already, muscle growth happens most of the times in a caloric surplus, when bulking. That’s why it makes perfect sense to try to be in a surplus as much as possible and in a deficit as little as possible, while not sacrificing any muscle of course.
Yes, building muscle and losing fat at the same time is possible but only in beginners, but even so the caloric restriction minimizes the protein turnover rate (protein synthesis over protein breakdown) and muscle repair. Therefore, when you are cutting you are not actually building muscle, or you are not building as much muscle as you could possibly build.
The only individuals that are should not be bothered by cutting too long are those that have built already the majority of the muscle mass that they can build naturally, but I’m sure most of us are not in that case.
That’s why the most of us will never reach the numbers you see in the studies about the maximum muscle growth potential in untrained beginners. According to Lye McDonald in the first year of proper training (and nutrition I would add), the potential muscle gain is 20 to 25 pounds.
I’ve never actually met a person who achieved this in 1 year. This implies training optimal and being in a surplus all the time.
Bottom lines, long cutting periods are not optimal for muscle growth or at a psychological level.
Losing weight fast
So, if losing weight slow is not optimal it means losing weight fast is, right? Well, yes and no. Losing weight really fast is not optimal either. You need to lose weight at just the right pace, while following a few simple rules.
As mentioned in the beginning of this post, losing weight at a rate of 2 or more pounds per week is too fast for most individuals, and losing weight a rate slower than 1 pound per week is too slow for most individuals. Therefore, generally speaking, a good weight loss rate is anywhere from 1-2 pounds per week, again depending on things such as body weight and body fat in each individual.
Disadvantage: Losing weight too fast can result in losing muscle mass.
For bodybuilders and fitness enthusiast this is the scariest thing – losing the muscle you worked so hard for. And I agree, losing muscle because a stupid thing such as a bad diet its nonsense. However, losing significant muscle mass only happens during aggressive calorie restricted diets.
Other than that, there are only advantages of losing fat at a fast rate, in a smart way.
Finding the sweet spot
What’s aggressive and what’s not aggressive in terms of caloric deficit then?
That’s a great question to ask and thanks to science and the studies out there we have a pretty accurate answer. And there’s also a ton of anecdotal evidence that supports this data.
The sweet spot that you want to be in is anywhere between 20% and 25% deficit. This is what studies show to be optimal in terms of fat loss rate and muscle preservation. To keep it safe, I prefer to stick with a 20% deficit and this is what I usually do in my cutting season.
Nevertheless, a 20-25% deficit should still allow the average active male to eat 2,000+ kcal a day and the average active female to eat 1,500+ kcal per day. If you are eating significant less than that you probably have a damaged metabolism caused by poor dieting background and you should to a metabolic reset.
My point is that you should not starve with a 20-25% deficit, unless you eat junk foods that are not satiating at all.
Staying in a more moderate deficit such as 10-15% is working and it will definitely not cause any muscle loss as long as you are getting your protein, but it has the disadvantages mentioned above: it takes too long and minimizes the bulking time, slows down metabolism too much and can make you cranky and just feeling blue after some time.
Moderate caloric deficits can work great for really overweight people who can lose weight at a faster pace though.
Alright, so we pretty much figure it out that a caloric deficit of 20-25% is optimal for losing fat as fast as possible while maintaining or building (if you are untrained) muscles mass. But what else can you do to support this?
High protein and high carbs
Calories are king, but macros are important too. High protein and high carbohydrate diets will support muscles mass though increased protein turnover and by providing sufficient energy and restoring glycogen inside the muscles, which means more effective workouts.
Forget about the low carb diets people. These do not support an active person in any way, and have inferior benefits if your goal is to recompose your body by losing fat and building muscle. Low carb diets will just make you skinny fat.
Get at least 2 grams of protein per kg of body weight, 50-60 grams of fat and take the rest of the calories from carbs when cutting. Beside the fact that carbs fuels your body in the gym, they also make cutting so much easier because high carb foods are very satiating.
Train high intensity/heavy
Lifting heavy weight (in the range of 80-85% of your 1RPM and above) is not only beneficial for muscle building, it also support fat loss by slightly increasing the metabolic rate. According to this study, training high intensity (80-85% of 1RPM) results in an increased metabolic rate for up to 3 days post workout, as opposed to training with lighter weight (45-65% of 1 RPM).
There you have it right there. Time to grind!
Throw a little bit of cardio in there
Lastly but not least, by adding just small amounts of cardio gives fat loss a boost. Don’t fell off the wagon though and start doing cardio like crazy. It will hurt your gains.
Just as Mike Matthews I am a big fan of HIIT cardio just because of the fact that it takes less time to do it, but it looks like it is also more effective than other types of cardio. If you don’t like cardio you don’t need to do it. It’s not necessary; there are ways to lose weight without cardio training.
I am not a big fan of cardio and I don’t do it every week even if I’m cutting, but it definitely helps.