Lose Weight Quickly without Exercise using Science

Losing weight quickly is based on one scientific principle.

Ensure that calories out is MORE than calories in.


  • Estimate your TDEE, using this site,
  • Set a realistic goal. Aim to eat 15% less than your TDEE.
  • Stick to your strategy for a few weeks, whether it is keto, paleo, IF or If It Fits Your Macros (IIFYM)
  • Be consistent.
  • Pro tip: Protein is the most satiating macro, so it will help control your hunger.

That’s it. That’s how you lose weight. To lose weight quickly? Ensure you eat less than 300-400 calories than you need.

If you want to calculate how many calories you need to lose weight, just head to this site,

Calculate your Total Daily Energy Expenditure (TDEE). Then make sure you eat about 300 calories less than that every day.

Okay, but there is a lot more detail to losing weight quickly than just eating lesser calories than you need. What about diets? Keto? Paleo? Intermittent fasting (IF)? What about my lifestyle? Buffets? Luxurious dinner dates?

Before you embark on the journey of losing weight quickly, you must treat this as a lifestyle change. 

I am not saying you need to completely revamp your whole life and suddenly become a fitspo when you never touched a barbell your whole life. What I am saying is that you need to be more disciplined and become more aware of what goes into your body. Do not focus on making an extreme change. Because, chances are, you will be unable to continue for a sustained period of time. You need to be consistent.

Now onto the details.


you don't need exercise. You just need lesser calories to lose weight quickly.
Dessert or Dumbbell?

The whole principle about losing weight is based on Calories In, Calories Out (CICO). Whether consciously or not, humans have regulated their weights based on CICO.

What consists of CICO? It can be broken down into 2 segments.

Calories In. This is the amount of food we consume in terms of calories.

Calories Out. This is the amount of calories we burn on a daily basis, whether it is due to daily activities, food thermogenesis or exercise.

Therefore, there are 2 ways we can lose weight quickly. Reduce the calories we consume. OR/AND Increase the calories we burn.

Reducing Calories In

It is ALWAYS easier to reduce the calories we consume. Why? Here is an example.

A kit-kat bar contains about 220 calories. To burn that off, we need to walk at least 6800 steps. I would say that resisting that kit kat bar would be easier.

This is why there are people who do not exercise but are still able to lose weight quickly. Here are some tips.

Eat less.

With lesser calories to “spare”, we definitely have to eat less. The easiest way is to cut down on the volume of food we eat. Maybe skip the afternoon snack. Take 2 spoons of lesser rice during dinner. Have less gravy when you order cai png from the auntie.

If you are money-minded like me, budget your calories. Tie your food choices with money. Then, you will not overeat and spend too much on food. Not only do you get to save money, you get to eat the appropriate portions too.

Go for less calorie dense foods.

These foods mostly include vegetables or fruits. They do not have to be pure healthy clean chicken breast steamed with plain water and broccoli. Don’t be afraid to innovate. If you consume less calorie dense food, you get to eat a larger volume, so you will not feel as hungry later.

Some of these less calorie dense foods include corn, spinach, bok choy, broccoli and eggs. 

100g of eggs is 155 calories.

100g of corn is 86 calories.

100g of spinach is 23 calories.

100g of bok choy is 13 calories.

Now compare this number with a typical bubble tea which contains 160 calories. Not only will these foods provide you with the proper micronutrients, like your vitamins and minerals, they also make you feel more satiated. So that your stomach will not go grumbling throughout the day and you will feel better when dieting.

Yes, these foods may seem very “healthy” and very drastic from what you usually eat, you KOI-loving green tea macchiato fanatic. However, like what I said before, this is a lifestyle change. You have to embrace it. Moreover, you want to do this without exercise, how else are you going to accomplish it? Change your perception about these foods. They can be healthy too.

Go for whole foods.

Skip out on your processed sugars, coca-colas and the ever-so-tasty bubble tea. Those stuff are so calorie-packed that it just hits your brain with a wave of dopamine that keeps you wanting more. Learn to cut back on consumption of such drinks. Opt for healthier choices, such as whole foods. They tend to pack lesser calories, so you can eat more volume, while not feeling as guilty. Do note that this is a general rule of thumb.

For example, when you are shopping for groceries, just look for whole foods. Stay within the whole foods section for the bulk of your trip, and make your purchases there. Avoid processed meats like ham, sausage, luncheon meat. They come with worse side effects than being calorie-packed too. I will explain in a future article.

Also, look for healthier choice logos, my fellow Singaporeans.

healthier choice option label. choosing such food options can help in losing weight quickly.
Healthier Choice Option Label

*Pro-tip: Protein is the most satiating macro out of the 3. Therefore, if you are in a dilemma, pick the protein. It will keep you full for a longer time without you craving for more food later when your stomach starts to grumble later. This includes the leaner cuts of meat such as your chicken breast or tenderloin, pork tenderloin. I tend to avoid beef due to my religion. Even though I advocate for leaner cuts of meat, do avoid the eye of round for beef. It is just flavourless according to many of my friends and is really not worth it.

If you are going to regret your food choices, you will be less likely to stick to your plan and you will give up earlier. So, pick something sensible and tolerable such that you can stick to the plan consistently for a period of time.

Increasing Calories Out

Maybe you just had to have the kit kat bar in the afternoon to boost your energy. Maybe you had that extra serving at the cai png stall during lunch. Maybe you just want to accelerate the process of weight loss.

Well, then you would have to adopt another strategy which would be to increase the number of calories you burn. By increasing Calories Out, you will be in a caloric deficit and therefore you will be able to lose weight. There is only one way that I can think of that is still practical for most people in Singapore (PMETs).

Stand more.

During your relatively sedentary office hours, make the effort to stand up more and walk around. Although negligible, it will burn slightly more calories. After a couple of weeks, you will definitely see some effect, albeit small.

How do I organise my macros?

Okay, so this is where it gets very science-y, and you probably do not need to know this for weight loss. But hey, more knowledge is always better right?

Firstly, there are 3 macronutrients, they are protein, carbohydrates and fat. Throughout this article, I have been rambling about calories and cutting your calories in favour of weight loss.

Well, if calories is king, protein is queen.

lose weight quickly with high protein consumption

Protein should form the foundation of your macros. Recommendations by Eric Helms, a highly regarded strength athlete and coach who is probably way smarter than I am, go up to 2.8g/kg of body weight while dieting to preserve muscle., an independent organisation which analyses nutrition, recommends 1.6-2.2g/kg of bodyweight. These are all good numbers to base off on. If you just want a number to stick to, I would say for the general overweight Singaporean male who is trying to lose weight quickly(assuming 90 kg at 175cm), a good amount of protein to aim for would be 150g.

This number may shock some people. Most common questions include.

Can my body absorb so much protein?

Will so much protein harm my liver or kidneys?

How am I supposed to get so much protein in a day?

The short answer for the first 2 questions would be yes. The short answer for the 3rd question would be up to you. Try to get protein in every meal, it will really help.

Here is a simple meal plan for you. This is actually a real meal plan for myself. If I am in a weight loss phase, I will actually eat these foods everyday for a period of about 3 months, and it has given me very good results.

Meal Plan

a strategic meal plan is what you need for fast weight loss
A strategic meal plan will help you.


  • 1 bowl of oatmeal, steamed in water
  • 1 bowl of oatmeal, steamed in water

I have been eating these two food items for 3 years now and they have become part of my lifestyle. They are just so good for your body and it starts your day on the right note.


  • Cai png – 2 meat 1 veg

I go for cai png because it is the economical option for me, usually costs about $4. Remember, you cannot afford to snack before lunch and after lunch, because we are reducing calories intake. It is okay to feel hungry. It is a normal and natural body reaction. My best advice would be to not think about it and focus on the task at hand.


  • 1 bowl of rice
  • 1 serving of vegetable
  • 1 serving of meat
  • 1 serving of fish
  • 1 serving of soup

This is usually what my mom cooks for dinner. (Thanks mom) So it really varies. This will be your biggest meal of the day.


  • 1 ice cream
  • 1 fruit (apple/strawberries/pear/watermelon/papaya/banana)

After all that sacrifice throughout the day, I just cannot stop my sweet tooth sometimes. I really like ice cream and it gives me a sense of satisfaction. The fruit is to ensure that I have at least 5 servings of fruit and vegetables throughout the day. There is a science article showing that the higher the consumption of fruits/vegetables, the lower than chance of early mortality. Although correlation is not equal to causation, I prefer to err on the safe side, with our high protein intake, it is better to eat more fruits/vegetables. After all, they are not calorie dense and they will keep me satiated anyways.

Do note that this meal plan is quite extreme because it is for my cutting phase. Take this plan as a skeleton and add and remove certain food items according to what you prefer, this is the beauty of If It Fits Your Macros (IIFYM).


Supplementation is really not necessary. It is like what the word suggests.

You might be wondering whether you need whey protein supplements to help you achieve that target. My answer would be no. It is a SUPPLEMENT, not a REQUIREMENT.

“If daily protein targets are achieved through dietary protein alone, supplementation is unnecessary.” –

Okay now onto carbohydrates and fat. I have good news.

This is completely up to you. It doesn’t really matter in my opinion. The whole “carbs make you fat” notion is completely untrue. People think that way because they relate sugar and carbs and thus deem both of them unhealthy. As long as you keep both carbs and fat within your stipulated caloric intake, you should be able to lose weight quickly. This is the beauty of IIFYM.

However, some of you may want a rough estimate. Personally, I like to eat slightly more carbs than fat. This is because fat tends to come from processed food and other kinds of more expensive food. Carbs tend to be cheaper. Also, I like to load up on more carbs before my lifting sessions so as to give myself more energy for the lifts, hoping that I can squeeze 1 or 2 more reps on the final set.

After allocating the number of calories to protein, I like to allocate the remaining 65% of calories to carbs and thus the 35% would go to fat. However, this is really just a rough guide. If it is more convenient for you that day, you can always increase your fat intake and decrease your carb intake, as long as it fits your calories at the end of the day.

Just keep in mind,

Protein: 4 calories per gram

Carbs: 4 calories per gram

Fat: 9 calories per gram

What diet strategy should I follow to lose weight quickly?

Follow the best one that suits your daily lifestyle. Eating less and exercising more may already be such a drastic change to your lifestyle. Why make it even more extreme by following a particular diet strategy?

Flexible dieting AKA IIFYM is really the best method for most people. Most people should find this method to be very easy to adopt and integrate to their lifestyle.

However, if your lifestyle is different and you find other diet strategies to be more helpful, such as keto, paleo or intermittent fasting, do go ahead and try them. (I will write articles about the various strategies soon!)

But make sure that you can stick to them. Consistency is key. Your strategy is not.

Do I need to track my calories?

No. I personally tried tracking my calories for a period of time, roughly 2 weeks and gave up. You are not preparing for a competition to be 4% body fat or bulking up for a strongman competition. Tracking your calories can really be an obsessive habit and get in the way. This action of tracking your habit may make dieting seem more like a mental challenge to you. And thus, you may be unlikely to do it.

Can I really lose weight without exercise?

To all the doubters that have read through the article this far and are still not convinced. Yes, you can really do it without exercise. If you don’t believe me, here is someone who lost 18 kg eating a chocolate-only diet.

Why does this work? Chocolate has a set amount of calories. Say a Snickers Bar. It has 215 calories despite being only 44g. If you eat less than you burn in a day, you WILL lose weight quickly. Using the TDEE calculator above, let’s say you need 2500 calories for a maintenance weight. This means that even if you ate 11 Snickers Bars, 215 x 11 = 2365 <2500. You will still lose weight quickly. This is because you are consuming less calories than what you need.

You can try it out yourself, but I do not recommend it. A Snickers Bar is packed with processed sugar and is mainly carbs. It has basically no micronutrients, which will leave you nutrient deficient at the end of the weight loss period, which is unhealthy for you.

But if you want to accelerate it…

Exercise will boost your weight loss process.
You don’t need it. But I mean… it will help.

Now you may want to lose weight quickly without sacrificing on your food choices. What can you do? Well, if you do not want to sacrifice your food choices, you have to make sacrifices somewhere else in your lifestyle. That is to exercise. Exercise will help you accelerate the process, simply because you are burning additional calories.

I do recommend people start exercising. It is easier to lose weight quickly when you exercise. This is because exercise gives you the extra shot of dopamine that you missed from the extra consumption of food. The newfound dopamine from exercise can be your healthy “food replacement”.

Go out there and try different kind of exercises. You don’t have to do the typical running and sweating. There are a lot of kinds of exercises you can embark on. Weightlifting (not an effective tool to burn calories, but is still considered exercise), HIIT, swimming, cycling, boxing, martial arts, etc.. Just move more. Walk more. Make use of the step tracker that Health Promotion Board gives every Singapoeran. That thing will earn you vouchers (for unhealthy food like KOI…, but hey it’s free money)!

And with that, congratulations, you are now equipped with the knowledge to lose weight quickly. Remember that consistency is key. 

Execution of your slimming plan

Now that you have the knowledge. You need to know how to execute the plan. After all that planning and calculation of your TDEE. Remember to take progress pictures.

Every day, at the same place and around the same time, take out your iPhone and snap a picture of your own body. Do it around the same time for similar lighting because lighting can give you a false illusion that your body is changing. This process of taking progress pictures will keep you accountable. And when you are on your path to success, you will feel more motivated and more inspired to continue hustling and work harder to achieve your goal of quick weight loss.

After all, weight loss is not easy. I have done it multiple times in my life. But it requires discipline. After this journey, I can guarantee that you become a more disciplined person overall and generally become a better person, both physically and psychologically.

Once you do this for a few days, begin to take note of your mood. This is to ensure that you are happy with your progress and your lethargy will not greatly affect your life.

If you cut a significant amount of calories, such as 500 calories or more, be prepared to see a huge drop in weight for the first few days. Do not panic and do not be over-excited and claim that your weight loss journey is over.

The Science Behind It

It is probably due to water weight. There is one main reason behind it. Glycogen, a form of glucose, is stored in our liver, muscle and fat cells. When you suddenly cut down on calories, your body will naturally use the glycogen stored in your liver and muscle cells and fat cells. The glycogen stored in your liver will deplete the last because it is the largest storage as opposed to the other two. This is why it is so easy to drop the first few pounds.

After you shed the first few pounds, quick weight loss becomes tougher and more of a mental challenge. This is because you start to feel a bit more lethargic. Moreover, your body goes into “fight or flight” mode, where it begins to send signals to your brain to consume more food, which is why you feel so hungry all the time. But if you are able to resist it, your body will have no choice but to deplete the fat cells for energy. This is because converting fat cells into energy, such as ATP, is a very long process and your body would almost always prefer glycogen, which is why glycogen depletion occurs first.

Self-discipline…Discipline yourself.

Okay, with this knowledge about how your body works, now you will need to rely on your self-discipline. Continue taking progress pictures and start taking your weight on a daily basis. I have tracked my weight every day for 2 years. Every morning, after I wake up, I will answer nature’s call. After that, I will take my weight reading and record in my phone. I personally use the Simple Weight Tracker, it does its job well. Remember do it consistently.

When do I stop dieting?

Stop your diet when you feel happier about yourself and your own body image. Take the most recent image of yourself and compare with your body in the past. If you’re happy with the transformation, then stop. 

Once you have decided to stop, slowly increase your calorie intake again. Do not go back to your past calorie intake if you do not want to undo the results. Maybe add an extra serving of vegetables first. Then maybe add an extra serving of meat. Then maybe try snacking and find your maintenance caloric intake again. Once you are satisfied, stick with that and you can begin to “eyeball” your food choices. This is because, I believe by then, you would have been trained enough to be able estimate the calories of a food item.

Good luck.

Good luck on losing weight!
It isn’t easy, so all the best!

With that, you should have sufficient knowledge about losing weight quickly. I wish you the best of luck on this journey, and I hope you come out a better person!

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