Calorie restriction is one of the most robust interventions for health and weight loss. I could spend all day telling you about its benefits, but instead, I will give you something way more practical. Today I will explain how much weight can you lose eating 500 calories a day, and most importantly, how to do it correctly.
In general, you can lose weight by eating 500 calories a day, as long as you use it intermittently (just like Alternate day fasting). However, this approach is not for everyone becasue reducing your food intake down to 500 kcal everyday can create a chronic calorie restriction and the risk of malnutrition.
This is my general answer but if you wanna know more details like how much weight can you lose, and who should consider this approach, keep reading.
Is Eating 500 Calories a Day Good Idea For Weight Loss?
In general, eating 500 calories a day is good for weight loss because it creates a negative energy balance where the total daily energy expenditure exceeds energy intake. Over a period of time, the body has no other option but to utilize fatty acids for energy and as a result, we lose weight.
But let’s be clear. Just because you can survive on 500 kcal, it doesn’t mean you have to. It doesn’t even mean you have to do it every day.
Calorie restriction, just like exercise, offers multiple health benefits. But if it’s done too much, it brings more harm than good.
For example, eating 500 caloires a day for one day a week can boost your energy and reduce overall appetite, whereas eating 500 calories a day for 7 days can lead to fatigue, increased stress and muscle loss.
You get it?
The first option is healthy, it energizes you and (over time) leads to consistent weight loss. The second option where you eat only 500 calories everyday is too little, and can create more harm than good.
Just because something is good for us, it doesn’t mean more will be better. Drinking 2-3 cups of coffee can enhance your cognitive and physical performance, where drinking 20 cups per day isn’t the best idea.
The same with calorie restriction.
This concept is called the hormesis effect, which is defined as a dose-response balance. The low-dose of dieting leads to positive stimulation and high-dose of the same dieting leads to inhibition and negative feedback.
Take a look at the graph below.
From this graph, the blue line on the left indicates the action (e.g. eating 500 calories a day) with a low dose of a stimulus our body responds in favor with great benefits.
The yellow line on the right shows the same action with a high dose of the same stimulus where our body start to feel worse.
Before I will show you how to use 500 calories a day in a smart way, let’s see what happens to your body when you’re on such a steep calorie restriction.
What Happens When You Eat 500 Calories a Day?
In the short term, when you eat 500 calories a day the body starts to improve insulin sensitivity and burn fat for energy.
After eating 500 calories per day for a long time, the body starts to create metabolic adaptations to keep the vital functions running. Metabolic rate decreases, gastrointestinal motility slows down, and muscle protein breakdown increase to supply essential amino acids.
Some of the most obvious changes after long-term dieting include:
- Lower resting metabolic rate
- Lower lean body weight
You see, there are not many human studies done on severe calorie restriction. With a good reason. Who the hell would sign up for that? Being locked down in the laboratory chamber for 6-12 months eating 500 calories or less.
But there is a handful of studies done around World War 1 and World War 2 by the people who actually volunteered for the experiment.
In my article about “calorie restriction and metabolism“, I’ve commented in-depth about the “Minnesota Starvation Experiment”, so feel free to check it out.
In short, apart from obvious anthropometric changes like body weight and body composition, there are several psychological changes going on like emotional stress, and anxiety, to name a few.
Which gets us to the next point (don’t worry, it will all make sense in a moment).
Eating 500 Calories a Day Is Not For Everyone
Assuming that you have already decided you want to give it a try. You have your meals dialed in. You have your training in place. You’re ready to get that diced and saucy look where you can finally display your abs all year round.
But eating 500 calories a day is not for everyone. Some studies show that calorie restriction leads to eating disorders (source). Others who struggle to lose weight over the years or even decades, usually eat food not only to satisfy their physical hunger but as a way to make them feel better (source).
Food is not the problem. The problem is the problem.
As you can see from the graph, people use food not only to satisfy their hunger. They also use food to deal with problems, cope with uncertainty and worries, reduce stress and anxiety, and cope with emotional situations.
Now watch this.
Some people use food as the only way to deal with those life situations.
Yup. Dieting may feel like the hardest thing on the planet. Because when they give up food, they give up their entire mechanism to deal with problems.
So before I will show you how to do the 500 calories a day properly, take a hard look at yourself and think
- Can you do 500 calories a day for the next 3-6 months?
- Can you still feel energetic, productive, positive, and fully functional human beings if you only gonna be eating 500 calories a day?
If not, don’t worry. Read on
If yes, that’s great! Read on
How To Lose Weight On 500 Calories a Day?
We could spend all day talking about the pros and cons of doing a 500 calorie a day. Some people believe this is too much of a stretch. Others swear by it. Research about calorie restriction gives us guidelines. But it’s not definitive.
Some people have no results (or side effects) and some people respond extremely well (or poorly). And the reported number that you see in the end is average. So what does it mean?
That means forgetting the rules. Experiment instead. Research is a good benchmark. But there are some gaps in the so-called intra-individual variance. In other words, people are different.
That’s why you will never know if doing 500 calories a day is good or bad for you from reading papers of other people doing it unless you test it yourself.
So put your professor hut on because I will show you some steps to take to determine if this 500 kcal thingy is a good fit.
Here are the steps to lose weight by eating 500 calories a day for everyone.
Start from one day trial
A thousand miles journey starts with a single step. But to start walking you need to assess the territory. Is this something you can see yourself doing in the long term? The only way to know is to test it. Experiment.
You don’t have to (and you shouldn’t) dive deep into doing it for 7-days. Be smart. Start where you are, not where you think you should be.
Plan your trial day ahead of time.
- Choose a day that is less busy
- Divide your meals in two 250 kcal each
- Start your day with a spoon of coconut oil on the empty stomach to curb the hunger (this way you can have your first meal a little later)
- Prioritize protein and starchy fiber-rich foods to suppress appetite
- Foods like potatoes have the highest satiety index and can keep you full for longer
- Drink plenty of water and zero-calorie beverages throughout the day
- Some evidence shows that caffeine and green tea act as an appetite suppressants
After the trial, you will know how your body responds to 500 kcal and if this is a good fit for you or not.
Document what you eat, and how you feel
This is the most important part. You cannot know if eating 500 calorie a day is good or not for you unless you know how exactly it makes you feel. Here are some questions to consider.
- How do to feel when you’re hungry?
- Are you constantly thinking about food?
- Do you struggle to focus and keep a clear head?
- Do you feel shaky or anxious?
You need to write these down. Write exactly how you feel during the day, around mealtime, after eating, etc. This will teach you so many valuable lessons about your reactions to food (or lack of it).
Always ask yourself – How is that working for me? and be honest with your answer. Use the food journal to document your thoughts, feelings, emotions, and food.
Make an outcome-based decision
When you feel like 500 kcal a day was a piece of pie, schedule the next day as your calorie restriction day. It doesn’t have to be back to back.
It can be any combination like:
- Monday and Saturday
- Tuesday and Friday
- Saturday and Sunday
It doesn’t matter. Now you’re on two days eating 500 kcal a day. Then you just rinse and repeat until you find the sweet spot.
You can find that doing 2 days a week of calorie deficit is enough. You may find that you can handle just one day. Some people can do it for 5 days.
Reminder: Doesn’t matter what others are doing. Find what works for you.
If you feel crappy after doing 5 days a week of eating 500 kcal, but you believe this will give you results faster, I will stop you right there.
It won’t. You will burn out. Remember the hormesis effect?
Find what works for you.
How To Eat 500 Calories A Day And Feel Full?
In the last step I will show you my best tips on how to eat 500 kcal and be full for longer.
In general, the most effective way to feel full by eating 500 calories a day is by eating slowly for at least 20 minutes, eating without distractions, and choosing high-protein and high-fiber foods that will increase satiety, and lower hunger feelings.
Feeling full is all about how you eat and what you eat. Here is the basic step-by-step tutorial on how to eat.
Feeling full and satisfied is triggered after the first 20 minutes of eating. This means if you finish your meal in 3 minutes while watching a Netflix show, you will feel hungry very soon.
But if you spend 20 minutes instead of 3 minutes, this will trigger your gut peptides to raise and they will signal to the rest of the body that indeed you’re full (source).
This fullness will last for a long time. Here is the checklist of how to eat slowly.
Eating without distraction
Mindless eating causes us to overeat. Mindless eating is when you’re doing something else while you’re eating. Driving the car, listening to music, or watching YouTube. Mindful eating is when your all attention is strictly focused on your meal.
Several studies show that people who eat mindlessly, consume more calories. So when you eat slowly and spend 20 minutes on your meal, you will feel fuller for longer (source).
What Can I Eat For 500 Calories a Day?
The best foods to eat on 500 calories-a-day diet are high-satiety foods that will make you feel fuller. Those foods include potatoes, apples, oranges, oatmeal, meats, eggs, whole grain pasta, non-starchy vegetables, beans, lentils, and legumes.
How Much Weight Will I Lose If I Eat 500 Calories a Day?
On average, you can lose around 1–3 pounds per week on a 500-calorie diet, depending on your age, gender, physical activity, the amount of weight you lost already, and consistency. People who are just starting calorie restrictions will often see faster results than those who already lost some weight.
Also keep in mind that the more weight you lose, the more you reduce your resting metabolic rate due to the metabolic slowdown. To learn more about how this works, check out my article metabolic slowdown and how to avoid it.
In summary, eating 500 calories a day is not for everyone. Some people who rely too much on food as a stress relief will have a hard time radically changing their behaviors. But this doesn’t mean it cannot be done.
Following the steps that I’ve highlighted above ensure you’re doing everything according to your body response.
Keep in mind that this can take some time. Even eating slowly doesn’t always stick on day one. So use the checklists and stay consistent.