I could spend all day telling you about the robust benefits of calorie restriction, but instead, I want to give you something way more practical (you guessed it, how to eat 500 calories a day and feel full.)
(Picture below is my typical 500 kcal a day meal.)
Why did I start to eat 500 calories a day?
The reason why eating 500 calories a day sounds so appealing to me is simple. It works.
In the past, I tried all types of diets (keto, paleo, plant-based, etc).
(Yes, I’m obsessed with testing and trying all types of diets, but I also love food in general.)
For me, eating 500 calories a day (which in my case is around one medium-sized meal) helped not only to lose weight but also to develop a healthy relationship with food (more on that later).
It’s an effective way to drive weight loss
“Calorie restriction and VLCD are one of the most robust interventions for health and weight loss,” says obesity and weight management expert, Gary D. Foster, Ph.D.
(Yes, the same Dr. Foster who is the Chief Science Officer at WW, formerly Weight Watchers.)
In his recent randomized controlled trial, Dr. Foster documented 13 obese women who eat 500 calories per day diet (VLCD) for 6 months.
On average, all participants assigned to the VLCD group (the same group who were consuming 500 calories a day) lost 12.1% of fat and 3.6% of lean body weight.
In the contrary, the second group (balanced-deficit diet group) eat 1,200 calories a day and lost 10.6% fat and 4.1% of lean body weight.
(You got it, the group who eat more calories lost more muscle and less body fat.)
What do 500 calories a day look like?
Like this. (See the picture below.)
For me, 500 calories are usually meat and some veggies. Yes, most of my meals include plenty of protein. (I will cover more about protein later in the article.)
Is eating 500 calories a day a good idea for weight loss?
Sure, eating 500 calories a day can get you lean and accelerate weight loss. However, this approach is not for everyone.
On the one side of the spectrum, it creates a negative energy balance where the total daily energy expenditure exceeds energy intake.
And, over a period of time, the body has no other option but to utilize fatty acids for energy. As a result, we lose weight.
On the other side, eating so few calories a day it’s definitely not for everyone.
It does not have to be done every day
Just like exercise, calorie restriction offers multiple health benefits, but it does not have to be done every day.
In fact, if exercising is done too much or for too long, it may bring more harm than good.
For instance:
- dieting for 1-2 days a week can boost your energy and reduce overall appetite; whereas
- eating 500 calories a day for 7 days may lead to fatigue, increased stress, and difficulty in concentration.
What’s the difference?
- The first option is easy and may lead to consistency. It energizes you and (over time) leads to consistent weight loss.
- The second option is not easy and may lead to burnout. The option where you eat only 500 calories every day is not sustainable.
Just because something small is good for you, it doesn’t mean more will be better.
- drinking 2-3 cups of coffee can enhance your cognitive and physical performance; but
- drinking 20 cups per day isn’t the best idea.
You can start small from 1-2 days per week
This concept is called the hormesis effect, which is defined as a dose-response balance.
For instance:
- low dose as mild dietary stress (aka dietary restriction) may lead to positive stimulation; and
- high dose as severe dietary stress may lead to inhibition and negative feedback.
(Take a look at the graph below.)
- The blue line on the left indicates the action (e.g. eating 500 kcal) 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 starts 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?
Very low-calorie deficit (500kcal/day) without malnutrition can improve risk factors involved in the pathophysiology of type 2 diabetes, cardiovascular diseases, cancer, and neurological disorders in humans,” says calorie restriction and eating behaviors expert, James Dorling, Ph.D.
Dr. Dorling has published many articles about calorie restriction, longevity, and aging. He is a lecturer at the University of Glasgow and specializes in human nutrition.
“Intermittent fasting is a great alternative for people who fail to fully adhere to prolonged periods of severe energy restriction,” says Dorling.
Dr. Dorling says “Initially, when you eat fewer calories, the body starts to improve insulin sensitivity and burn fat for energy.”
Eating 500 calories a day and not losing weight
“The rate of weight loss is expected to slow down because of the hormonal adaptations, which may resist weight loss,” explains Dr. Dorling.
In other words, after eating 500 calories per day for a long time, the body starts to create physiologic changes and slow down fat loss.
“Some of the aforementioned adaptations include lower resting metabolic rate,” says Dr. Dorling.
Is 500 calorie a day diet safe?
Safety is always important. That’s why you won’t see many long-term 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 is not easy (nor fun)
In my article about calorie restriction and metabolism, I’ve made in-depth commentary about the “Minnesota Starvation Experiment”, which I recommend you read.
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.
Eating 500 calories a day is not for everyone
Yes, even if you’ve already decided to give it a try, you need to remember that eating 500 calories a day is not a picnic.
“Some people may experience beneficial psychological and behavioral effects. Others may experience overeating and eating disorders,” says a professor at the University of Toronto, Peter C. Herman, Ph.D.
“People 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,” explains Dr. Herman.
If hunger isn’t the problem, food isn’t the solution
(See below at the graph.)
As you can see, the graph above illustrates how people use food.
(This is in line with what Dr. Herman is talking about.)
“People don’t overeat becasue they feel hungry. They use food to deal with problems, cope with uncertainty and worries, reduce stress and anxiety, and cope with emotional situations,” says Dr. Herman.
“Some people use food as the only way to cope with those uncertain life situations.”
(Yup. Dieting may feel like the hardest thing on the planet.)
And, when they give up food, they give up their entire mechanism to deal with problems.
How to lose weight in 500 calories a day?
It’s time to put on your scientist hat. Here are the steps you can start doing today to help you lose weight by eating 500 calories a day.
Be realistic
Ask yourself, is eating one 500 calorie meal a day something you can see yourself doing in the long term?
Start from one day trial
Start from 1-2 days per week. Once you feel more confident, add more days later.
You don’t have to (and you shouldn’t) do it for 7-days. Be smart. Start where you are, not where you think you should be.
Plan your trial day ahead of time
Start by assessing your schedule. Choose a day that is less busy.
Break it down into two meals
If one meal a day sounds unrealistic, divide your 500 calories into two 250 kcal meals each.
because I will show you some steps to take to determine if this 500 kcal thingy is a good fit.
Think about how to be less hungry
Start your day with a spoon of coconut oil on an empty stomach to curb hunger (this way you can have your first meal a little later). Prioritize protein and starchy fiber-rich foods to suppress appetite.
Add foods like potatoes. They have the highest satiety index and can keep you full for longer.
Stay hydrated
Drink plenty of water and zero-calorie beverages throughout the day. Some evidence shows that caffeine and green tea act as 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 calories 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?
Write these down. Write exactly how you feel (during the day, around mealtime, after eating, etc.) This can teach you so many valuable lessons about your reactions to food (or lack of it).
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 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.
Look at how you feel
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.
Eat slowly
Follow the checklist below.
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.
Spend 20 minutes instead of 3 minutes.
Eat without distraction
Mindless eating is when you’re doing something else while you’re eating. (This may trigger
Turn off any electronics during your meal. Eat mindfully, when your all attention is focused on your meal.
What can I eat?
The best foods to eat on 500 calories-a-day diets are high-satiety foods that will make you feel fuller. Those foods include:
- potatoes
- apples
- oranges
- oatmeal
- meat
- eggs
- whole grain pasta
- non-starchy vegetables
- beans, lentils, and legumes.
How much weight will I lose if I eat 500 calories a day?
Good question.
Aiming to lose 5–10% of initial body weight within the first six months of eating 500 calories a day is a realistic approach (that’s around 1–3 pounds per week).
The overall weight loss may vary and will depend on your age, gender, physical activity, and the amount of weight you lost already.
Also, people who are just starting calorie restriction may often see faster results, compared to those who already lost some weight.
Conclusion
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 others respond extremely well (or poorly).
And the reported number that you see in the end is average.
In summary, this approach works but 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.
This doesn’t mean it cannot be done.
Following the steps I’ve highlighted above ensures you’re doing everything according to your body’s 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.