How to lose 15 pounds of fat in 3 months or less

by Alex Chris on April 9, 2012 · 23 comments

lose 15 pounds

Everybody knows that in order to lose weight you need to burn more calories than you consume by following a balanced diet and doing regular exercise. This is the abstract definition of weight loss. In this post I will explain step by step what you need to do if you want to lose 15 pounds of fat in 3 months or less.

Step 1: What is the effort to lose 15 pounds?

15 pounds of fat is equivalent to 52,500 calories

The first step is to understand the effort you have to put in order to lose 15 pounds. One pound of fat is approx. 3500 calories. This means that in order to reduce your weight by one pound you need to save 3500 calories. Based on this formula you can easily calculate how long it will take you to lose 15 pounds.

For example:

To lose 15 pounds in 4 months: you need to save 13125 kcals per month or 3281 kcal per week or 468 kcal per day.

To lose 15 pounds in 3 months: you need to save 17500 kcals per month or 4375 per week or 625 calories per day.

To lose 15 pounds in 2 months: you need to save 26250 kcals per month or 6562 per week or 937 calories per day.

To lose 15 pounds in 1 month: You don’t even have to do the calculation because this is not going to happen. For starters it is not healthy (the recommended amount of pounds to lose per week is 1-to 2 pounds) and second it is impossible (or at least not possible for the majority of people).

Hint: You can try different combinations to calculate how long it will take you to lose weight by using our daily calorie calculator.

So, now that you know what it takes to lose 15 pounds the next step is to find the most appropriate way to do it. Before getting into the details though, you need to understand the difference between weight loss and fat loss.

Step 2: How to lose fat and weight

Weight Loss Vs Fat Loss

We will cover in detail the difference between fat loss and weight loss in a new post but for the purpose of this guide you need to understand that when you are losing weight you are not necessarily losing fat. At the beginning of a weight loss process you will lose water weight and this is in many cases misleading. The scale will show that you lost weight but in reality what makes you lighter is the loss of water weight only. In order to lose fat you need to force your body to convert fat from the fat stores to energy. By eating lesser calories than what you need per day you are telling your body to look for alternative sources of energy and as a result you start losing fat. What you need to take from this section is that in order to lose fat you have to create a calorie deficit by following a balanced diet and doing regular exercise as we are going to explain below.

Step 3: Lose pounds by consuming less calories per day

There are many ways to lose weight by consuming fewer calories per day. The trick here is to avoid very restrictive diets but ensure that you are eating the right foods in the right quantities. If you are following a commercial diet or weight loss program then you must stay away from crash diets and select a diet (or program) that is balanced and spread over a reasonable amount of time. Very low calorie diets (or very low fat diets) do not work in the long term and should be avoided. The best weight loss diet is one that can generate permanent results in a healthy way. You can also read about low GI diets and carb cycling which are 2 very good and healthy diet options.

If on the other hand you don’t want to follow a formal diet you can create your own diet plan and eating pattern based on the following principles:

1.       Portion size does matter

There are many ways to control the size of your meals but taking the simplest approach is always the best. Since you are trying to lose weight, you can just divide your existing meal portions in half and save many calories. The change does not necessarily need to happen from one day to the next but you can gradually reduce your meal portions until you reach the desired size.

2.       Eat Slowly

It’s a fact that people who eat fast they eat more. The brain needs around 15 minutes to get notified by the stomach about fullness and by eating fast you provide your body with extra (and unneeded) calories that will end up in the fat reserves. So it’s better to eat your food in a slow pace, chewing and enjoying every bite.

3.       Frequent meals

I am sure you heard this before; eating frequent meals throughout the day has a number of benefits. First you aid digestion since it is easier for the stomach to digest smaller quantities of food. Second it keeps your stomach busy for longer periods, reduces hunger and as a result you avoid over calorie consumption with your main meals. Third it can improve your metabolism, meaning that the rate which your body burns calories is increased.

 4.       Water

Water plays a very important role in a healthy diet. For starters it has zero calories so drink as much as you want without worrying about adding to your weight. In addition it helps the digestion process and promotes detoxification (getting rid of unnecessary toxins from your circulation system). The recommended daily intake of water is 3.7 liters for men and 2.7 liters for women. Whenever you feel hungry drink a glass of water first and wait for 15-20 minutes. In many cases hunger will go away and you will save many calories. (see also Water for weight loss)

 5.       Avoid alcohol and soft drinks

If you want to lose weight fast then you need to avoid or reduce the consumption of alcoholic drinks as well as sugar full soft drinks.  Alcohol and soft drinks do carry calories and sometimes people forget about it and destroy their diets without knowing why. There are many diet friendly drinks to choose from and at the same time satisfy your desire for a drink.

6.       Cooking methods

It’s not only the ingredients of foods that carry calories but also the way you cook food. As a general rule of thumb avoid fried foods but instead go for baked or grilled. When cooking use olive oil instead of butter and other low fat products instead of full fat.

7.       Fruits and vegetables

The dietary guideline for the Americans recommends 5 servings of vegetables per day. Fruits and vegetables are synonyms of a healthy diet and should not be missing from your meals. There are many choices that can satisfy every need and taste and they can be taken for breakfast, lunch, snack or dinner. Eating fruits and vegetables on a daily basis is a habit you can get used if you try it for a couple of weeks. Once you ‘teach’ your stomach and brain to eat fruits everything else will be easier.

8.       Keep a diet journal

Keeping track of what you eat and drink throughout a day will make it easier to pinpoint mistakes in your diet and identify why you are consuming more calories than you need. I am not suggesting to become obsessed about calorie counting but having a clear picture of your daily calorie intake is useful especially if you decide to seek professional help.  There are many online tools to help you record anything you eat or drink and do all the calculations for you; why not use our own online calorie counter, it’s free and accessible by all devices.

9.       Go low fat and low calorie

Many products are labeled as low fat but if you carefully examine the food label they are not low in calories. The best diet friendly foods are those who are both low in fat and low in calories. Learn how to identify healthy fats and include those foods in your daily diet while avoid the consumption of full fat and high calorie foods.

10.   Be proactive when it comes to your diet

Do not wait to get hungry and then think what to eat. It is much better to plan your meals in advance so that you have full control of what types of food to eat and in what quantities.  Use a calorie counter to plan your balanced meals and prepare them in advance. Protect yourself by removing temptations (sweets, candies, potato chips, alcohol etc.) from your kitchen cupboards and do whatever it takes to stick to your plan.

Hint: You can also read our 50 Tips for Weight loss for even more healthy ideas.

Step 4: Lose pounds by exercising more

Dieting is only the half part of a weight loss equation; the other part is exercise and physical activity. Dieting can help you eat less calories but the only way to burn calories and keep the weight off in the long term is exercise. There are many forms of exercises which you can follow (cardio exercises, running on the treadmill, swimming, aerobics etc.) but one of the most effective forms of exercise for faster results is HIIT or High Intensity Interval Training.

High Intensity Interval Training for Weight loss

HIIT is a technique to use while you work out. What this technique suggests is to alternate between high to low and moderate training periods in a single work out.  This method keeps your body moving for the entire workout and as a result your heart rate is consistently at high levels and thus burning more calories. HIIT is suitable for people who want to lose a lot of pounds because fat burning is continued after the workout, in other words your Resting Metabolic Rate (RMR) is increased as you burn calories even when at rest.

HIIT can be used with both cardio type exercises and weight lifting. What is important is to follow the basic concepts i.e. alternate high with low training periods and do this consistently for 2-3 times per week.

Sample Workout schedule

The schedule below was compiled with the help of our personal trainers. Basically is a sample weekly workout based on the principles of HIIT (for Monday and Friday and normal cardio training for Tuesday and Thursday). Remember that before engaging into any intense exercise program you have to get the opinion of your doctor.

Monday and Friday -HIIT

Warm up for 5 minutes (walking)

After warm up walk for 40 seconds and then run for 20 seconds. Repeat 15-20 times (workout time 15-20 minutes)

Stretch for 2-3 minutes

Tuesday and Thursday –Normal Cardio Exercises

Wednesday – Free day

How to lose 15 pounds in 3 months or less – Summary

When you want to lose a considerable amount of pounds the best way to approach the process is like a big project – with start and finish dates, milestones, risks and assumptions. Create a plan by doing some basic calculations as explained above and stick to it until the end. If you encounter difficulties or if something does not go according to plan then do not get discouraged, change and refine the plan and continue until you are satisfied. Think positive and look forward for the finish date without worrying about short term delays.

Alex Chris
About the author

Alex is editor-in-chief of Calorie Secrets. You can connect with him on Facebook, Twitter and Google+. You can also contact Alex for any comments or suggestions about the web site.

{ 23 comments… read them below or add one }

Herta April 22, 2012 at 8:30 am

Is this healthy? I mean saving 600 calories per day is a lot..I want to lose 15 pounds before summer but I don’t know how to start

Alex Chris April 23, 2012 at 7:54 am

Herta Hi, I did explain above what is healthy and what is not, but there are also other factors involved like your current calorie intake, activity levels, age and health condition. So please give me more information and will try to help you out.


Itzel August 14, 2012 at 7:32 pm

Hi, I’m still a teen but I want to lose weight because I have a flaccid abdomen, but I dont know how! I’m really worry, do you have some tips or advises to me, please?

charlie November 14, 2012 at 7:06 am

I just started grad school, and I lost 15 lbs in a month, almost 20 lbs in 3 months (from 188 lbs to 169 lbs), without even trying. I gained a lot of weight during a year of working, mostly due to poor diet. I weigh less than I did sophomore year in high school! I never imagined I could lose so much weight without even trying.

It doesn’t have anything to do with counting calories, it has more to do with activating certain hormones in your body. Primarily, its a healthy lifestyle that matters. The biggest changes I’ve made in the past few months is a better diet, and walking around instead of driving. My diet is 90% non-processed food, I walk approximately 10 miles a week (due to large UMichigan campus), 1 hour of vigorous excercise (2 mile swim). That’s all.

charlie November 14, 2012 at 7:08 am

* 1 hour vigorous exercise per week

Alex November 14, 2012 at 3:22 pm

@Charlie – Well done! This is a great inspiration story and another solid prove that the best way to lose weight is by following a healthy diet and exercise

@Itzel – Have a look at this post to get started:

Marry February 6, 2013 at 4:38 pm


thank you for your great info. I’m 39 years old i need to lose 15- 20 pounds in 4 month do you
have any more hints for me. My eating habit is not good, in fact it is too poor i do not eat a lot
i do not eat a lot of fruit or drink water, but still i gained weight for the first time in my life.
i’v always had a very good body. i’m married, have 4 kids. my weight is 140 🙁 i’m 5.4 f

please any hint will help thank you very much

Amie February 20, 2013 at 2:02 pm

Hi, i weigh 123 pounds, I’m 15 and I would like to be 118, but i can’t keep the diet(s) up, please can i have some tips about how to keep motivated? Also I’m often busy with school work and i find it hard to keep the exercise part of my diet, any suggestions ?

Alex February 20, 2013 at 5:06 pm
jeremy March 31, 2013 at 7:41 am

Thank you I think after your article is not an excuse for losing weight

Ernie April 24, 2013 at 2:44 am

What you believe about the food you eat determines how it affects your body.
Body Mass Index (BMI) is an important factor to determine obesity.
t take it thinly because it is actually costly surgery and not getting the right outcome
may let down you.

Ann Winter May 2, 2013 at 6:16 am

Great post with thorough instructions. I tend to snack a lot and I tend to grab what’s ever convenient when I’m on a go. I guess that’s one of the biggest problems for me. But this will totally help with my 2013 weight loss resolution!

latone thompson May 30, 2013 at 7:50 pm

I’m 40yrs old. My energy level is not what it use to be & I work 11 hour days. I REALLY do want to start back exercising & feeling energetic. I’m now at 153 & would like to get down to 140. And of course tone my stomach, thighs, & arms in the process. What do you recommend, in oder for me to meet my goal w/in 3-4 months?
Thank You, Latone Thompson

Ally June 9, 2013 at 4:35 am

Hi there! I’m a 15 year old girl and I would like to lose 15 lbs over the summer (about 2 and 1/2 months). I currently weigh about 127 and would love to get down to 112. I’m 5 feet 3 inches. If I run about a mile and a half a day, along with other ab exercises and stuff, and eat better, will I be able to accomplish this? I’ve been trying to lose weight for a while but this time I’m dead serious about it. I would like to start next school year looking like a new person. Thanks!

Jafo June 11, 2013 at 10:49 am

For women 1200 caliories,and for men 1400 caliories a day.Add in cardio for more calories.Also,you can eat all that you want just 1 day a week.This is to let your body know it’s not starving.You will not gain 1 pound by having a feat just 1 day a week.

I love wheat bagels with smoked salmon and fat free cream cheese.Throw in some onion and capers as well.That makes a nice lunch.I also eat Kashi cerel with whole milk for break,lunch,or dinner.Dinner could be a nice chicken breast with rice or backed potato,with a vegi of your choice.

12 years as personal trainer.

Alicia June 11, 2013 at 7:26 pm

Great advice. I downloaded an app about two weeks ago called myfitnesspal, it tracks your calorie intake and since then I’ve lost 4 pounds already! I am 23 years old 5’4″ and now currently weigh 141 and would like to be at 125. I work out 3 times a week at the gym and I’m going to buy a bike soon so I can commute to work and lose more weight! I was interested in the HIT workout do you have more information on the interval training? other websites? Thank you!

Jasmine Eve August 6, 2013 at 4:41 am

im 19 years old, height is 5’3 and weigh about 113lbs
ive been on this ketogenic diet for about 3 months now, i lost about 10 pounds and feel great. But i still have visible fat on my back and tummy area that ive been trying to get rid of. i go to the gym 4-5x a week…i switch up from cardio to weight lifting depends of how i feel and im also taking some woman vitamins to help me reassure im getting all my nutrients and stuff since my diet is very strict. Im not sure what im doing wrong …somebody plz lmk asap!!!

Todd October 26, 2013 at 2:09 pm


I am a 220 pound 58 male looking to lose to lose at least 15 – 20 pounds. I quite smoking 10 months ago and have started gaining weight since. I have never had to lose wieght in the past and am lost when it comes to doing something I have never had to. I get mild exercise and am not one for going to a gym.

What is the besr advise you can give me to start on a thinner me? Thx!

Ashley January 17, 2014 at 4:50 am

Hi Alex,
I’m 29, 5’1″ and weigh 150, most of which I carry in my lower half and it is semi muscular actually. My problem is my arms and my middle/hips. I am going to try everything you’ve mentioned in the post above. I am looking to weigh about 130 by graduation in May, although looking healthier/fit is more important to me than the actual number on the scale. Do you think this is possible? Also, is there anything else I should be doing or any supplements I should add? I’ve heard that CLA helps a lot.

Sandra March 9, 2014 at 12:37 am

Hi I a am 43 in the past 7 months I’ve gained 30 pounds..I used to maintain weight between 130 to 135.can you please email me a good eating habit exercises to follow. I work both days and nights…my weight is in my mid section. .thanks sandra

patty March 13, 2014 at 6:16 pm

Hi A, I am a 51 yo, F, 5’10”, and want to lose 15 lbs. I am going to start this interval training today. I will eat only 1,000 calories/day. I am really struggling to lose. I lost 12 lbs since last Feb (2013), I have maintained this loss, but have been the same wt now since last June. (9 month Plateau) I have been “good”, but I’m not doing something right. I feel my metabolism is completely messed. I will commit to your suggestions. I’m writing this post to solidify my efforts to lose. I will re-post a few times during the next few months regarding my progress. Wish me well!! 🙂

Amy May 12, 2014 at 7:23 am

hi im 29yrs, f, 5’4″ and im weighing in at 194 lbs. im looking at losing around 15 pounds before mid August. so my understanding is if I exercise and burn 937 calories a day it is doable but how many calories should I be eating to start with?

Valencia Hernandez June 8, 2016 at 11:58 am

i’m trying to go vegan for two or three months will i lose weight to reach my goal.
I want to lose 50 pounds asap!!

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