When the average person decides to hop on the weight loss bandwagon the only aspects they’re thinking about are finding the nearest treadmill and dumping all their Little Debbie’s in the trash. If only they were to start on the IIFYM website and see that they could salvage those delicious treats!

Following IIFYM could not only allow them to continue eating the foods they love but by also starting with an IIFYM coach or using the macro calculator they could save themselves some serious dieting hassle. Little does this dieter know, there are intricate systems at work that could be helping or hindering weight loss.

Leptin: The Body’s Satiety Hormone

It’s been a long day and you’re STARVING. You’ve been daydreaming about pizza night for days. You settle in and eat 3 slices, push yourself back from the table; satisfied. Guess who’s to thank for this? Leptin! Leptin is a hormone that’s produced by the body’s fat cells.

The more fat in the cells, the more leptin that’s produced. These fat cells use leptin to tell the brain how much fat is stored. Therefore, the more fat you have, the faster you fill up, and the less fat you have, the more you can eat without feeling satiated.

Another way to put it; when you eat, your body fat increases along with your leptin, and therefore we eat less and burn more. Or, we don’t eat, our body fat decreases along with our leptin, and therefore we eat more and burn less. It’s the body’s survival mechanism (1). So for weight loss purposes, the more leptin, the better.

Ghrelin: The Hunger Hormone

It’s 11:30 AM. You steal a glance at the clock every 3 minutes; counting down the time to when you get to escape to the wonder that is the lunch break. What is it that’s triggering this intense hunger pang? Ghrelin!

Ghrelin is a hunger hormone and released predominantly in the stomach, but also small amounts in the pancreas and small intestine and travels through your bloodstream to your brain. Its main function is to increase appetite and promote fat storage.

Along with this increase in appetite, it also affects carbohydrate metabolism, sleep cycle, and taste sensation

When your stomach is empty, ghrelin is secreted and it signals your brain that it’s time to eat. The higher your ghrelin levels, the hungrier you’re going to get. The lower the levels, the more full you’ll feel, faster.

Another important job ghrelin takes on is releasing growth hormone which breaks down fat and aids in building muscle. So for weight loss purposes, the less ghrelin, the better (2).


How Do Leptin and Ghrelin Affect Body Composition?

We’ve covered what leptin is but what does this mean for body composition? Our bodies are fine-tuned machines that will do everything possible to maintain homeostasis.

When entering a diet phase, numerous hormones throughout the body begin to shift; most predominantly our hunger hormones. Have you ever noticed that many people who lose massive amounts of weight end up gaining most or all of it back?

There’s a reason for this. As fat mass decreases, so do leptin levels. With this decrease, there is no signal to our brain that we’re full and we can stop eating. Therefore, we continue eating past the point of usual satiety (3). It’s a cruel game our bodies play.

Rather than rewarding us for losing weight, our lower body fat results in less leptin, and therefore an insatiable hunger.

Paired with this decrease in leptin, ghrelin increases. When this hunger hormone increases, it signals your brain to eat. Obviously, when trying to lose weight, you’re trying to curb that urge to continue eating.

Along with this increase in appetite, it also affects carbohydrate metabolism, sleep cycle, and taste sensation (damn you hunger hormones, damn you!).

Sleep, What Sleep?

Another sick joke our bodies play on us? Fewer calories equal less energy. With this newfound exhaustion, you’d think sleep would be a dream (pun intended). But, as experienced dieters know, prolonged dieting can result in horrible insomnia. When we sleep, leptin increases.

So, with this lack of sleep, our leptin levels only worsen. Also, you guessed it; a lack of sleep also causes an increase in ghrelin. This increase in our hunger hormone, as we know, causes us to become even voracious.

Not to mention, cortisol increases while dieting, taking in too much caffeine, and not getting the adequate amount of sleep (4). So as we can see, it’s a vicious cycle that results in a stall in weight loss.

Which usually leaves the dieter frustrated and reaching for copious amounts of food whilst throwing their goals out the window.

Leptin Resistance

There isn’t much research or information on what causes leptin resistance, but many doctors believe it’s related to being overweight. What exactly is leptin resistance? That is when the brain struggles to detect leptin and doesn’t trigger the ‘I’m full’ response.

With leptin resistance, even if your body produces enough leptin, your brain still doesn’t receive the signal. Obviously, a massive problem when trying to control hunger and maintain or lose weight.

…leptin levels are affected by carbohydrates opposed to fat. So, by increasing carbohydrates on your refeed day, this may aid in increasing leptin levels.

If you think things can’t get worse; they do! With leptin resistance, the more you eat, the larger your fat cells become, thus resulting in higher leptin resistance. What’s interesting about leptin resistance is that it is much like insulin resistance.

Both of which are related to obesity (3). So thankfully you’re here on IIFYM and following a macro plan to keep those calories in check!


How to Avoid an Imbalance in Leptin and Ghrelin

We see it all the time. Competitors, or just insanely dedicated gym folks who are constantly pushing themselves to the limits. Hours and hours in the gym, and months upon months of hardcore dieting.

Most people assume if they have the will, they will find a way! What most fail to take into account though, are the mechanisms that go on beneath the surface.

As we’ve already covered, our hunger hormones can be a serious hindrance to weight loss efforts. So, if we want to continue pushing forward and reaching those goals how can we control these hormones?


For many, gone are the days of ‘cheat meals’. Why? The point of having a day of excess calories is to impact our hunger hormones, specifically leptin. While it may seem like the difference between a free meal and a refeed day are insignificant, this is untrue.

First, we’ll start with the obvious fact that a ‘cheat meal’, especially while dieting will have an impact on hormones already (yes, I can, in fact, finish this whole cake!). It can result in a massive and excess intake of calories. I’ve heard it multiple times, “you can’t gain fat from ONE cheat meal!” Sorry, but yes you can.

So, by having a controlled refeed, you can avoid the dreaded unnecessary fat gain. Second, leptin levels are affected by carbohydrates opposed to fat. So, by increasing carbohydrates on your refeed day, this may aid in increasing leptin levels.

Diet Breaks

I have a whole article covering this topic, but I will break it down as simply as possible here. There are two approaches with a diet break; a full and partial. A full diet break, when time allows, is always best, but partial still has its benefits. With a full diet break, you will take 10-14 days off of dieting.

This consists of increasing calories, tracking more loosely, and reducing cardio by 50%. With a partial diet break, you can either add 500 calories or increase by 20% to perceived maintenance.

Rather than loosely tracking, you’ll continue tracking as usual. The less body fat you have, the more frequently you’ll need to take a diet break. This break from your diet can aid in rebalancing those hunger hormones and keep you on track to continue losing weight.


While not everyone on IIFYM is a competitor, they can absolutely adopt some approaches competitors use. Competitors generally have a ‘prep season’ and an ‘offseason’. Prep is a period of dieting (calorie deficit), while offseason is spent in a calorie surplus.

Not only does a calorie surplus allow for potential muscle gains, it also puts the individual in a prime position for balancing those hunger hormones, and achieving adequate weight loss during their diet period.

Unfortunately, there’s a trend of competitors competing season after season, or not increasing their calories to an appropriate amount in their offseason.

This results in having to grind unnecessarily hard to peel those extra pounds off. Taking time off from dieting in order to build and rebalance hunger hormones is always a great idea to aid in overall health and to reach those long-term goals.

Although it’s tempting to see the competitors on weight loss programs losing copious amounts of weight and think ‘well if they can do it I can too!’; it’s just not reasonable.

As I stated above, these drastic weight losses almost always result in a dramatic weight regain. If you’re in it for the long haul, slow and steady wins the race.

While it may seem that willpower is the only aspect you need when venturing out on your weight loss journey, continue on keeping in mind that there’s much more beneath the surface that can affect your weight loss efforts and overall health in the long term.

So, if your weight loss stalls, keep those hunger hormones in mind and consider the above methods in order to move forward and hit those weight loss goals.