Calculator: How Long to Lose Weight

Jun 29, 2015 | fitness, Weight Loss

Ever wondered how long it might take you to lose those pesky 5 kilos?

Well here’s a nifty calculator that will tell you how long it will take you to lose weight.

Try the Weight Loss Calculator

Calories in vs Calories Out

At the end of the day, weight loss comes down to calories in/calories out. There are millions of crash diets and weight loss programs out there, and guess what, they all aim to achieve the same thing: they get you consuming less calories than your body burns. If there is a calorie deficit, you lose weight. If there is a calorie surplus, you gain weight. Simple (in theory!).

We can add layers of complexity around quality of food, macro and micro nutrients, hormones etc, but in my experience the majority of weight problems stem from a person eating more calories than their body needs. Let’s at least learn what our daily intake should be, get those calories from predominately healthy wholefoods, and deal with the rest later.

I’ve seen this work, even on the most stubborn of body fat cells. People who have been blaming their hormones, big bones, genes, thyroid, age etc are totally surprised when they learn the true calorie density of foods and what their true daily intake should look like. If this sounds like you, then try this formula.

Fat Facts 2 of 5: How Many Calories in Fat, Protein and Carbohydrates?

Weight Loss Formula

Step 1: Determine a weight loss goal: Maybe it’s to get to a healthy BMI, or a weight you remember feeling happy with.

Step 2: Use this calculator to set your desired timeframe: I suggest ticking the 500 calorie deficit or 15% deficit box, any more and you will be feeling quite hungry each day.

Step 3: Start tracking calories in. My Fitness Pal, 12WBT, Calorie King. These are all good apps you can use to track the food you eat. A shortcut would be going on a pre packaged, calorie controlled meal program such as lite and easy. Whatever you do, please don’t drink meal replacement shakes or go on a liquid diet, it’s not sustainable and you’ll gain whatever you lost as soon as you stop them.

Step 4: Start tracking calories out: I am LOVING my new Apple Watch to do this. It’s got a heart rate monitor on the underside so at any time during the day I can see how many calories I’ve burnt (and it’s super accurate as it uses your true heart rate). Otherwise use this calculator to guess estimate your BMR (basal metabolic rate) and add about 500cal to that on the days you do a vigorous 60min workout.

Step 5: Determine your calorie deficit or surplus at the end of each day. Subtract Calories you burnt from the calories you consumed. If you are reaching a calorie deficit each day you WILL lose weight.

Step 6: Weigh yourself 1-3 times per week: People have a love hate relationship with the scales, but they are simply telling you the facts. Try to remove as much emotion out of your weigh in day as you can, stay pragmatic and honest with yourself. Remember a two day blowout on the weekend CAN take the weekly deficit and wipe it out. Wednesday is my favourite day to weigh in, as it’s far enough from the unpredictability of the weekend yet close enough to remain front of mind. Weigh yourself first thing in the morning, naked, after a pee.

Why Am I Not Losing Weight?

Commit for Two Weeks

Tracking calories in and out does take commitment and time at first. But the great news is there are such good tools available nowadays to make it so much easier. Also once you learn the caloric value of all the common foods, you remember, and you can make really good, quick choices at a glance. This information stays with you for LIFE!

So commit to this properly for two weeks. Track your improvements, and if you feel confident you can slacken off the tracking. If your weight plateaus, get back on the tracking wagon.

Give it a go, report back, and remember a 15% reduction in daily calories will not deprive you from your favourite foods, but it WILL get you great results!

Try the weight loss calculator 

Next Steps

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