When it comes to weight loss there is no way to get away from the science. You need to be in a calorie deficit in order to lose weight, but just how much if a deficit and what is the best way to do this in a way that doesn’t cause you extra stress or end up with you gaining the weight back again later on?
The industry standard is that in order to lose 1lb of fat, you need to burn 3,500 fewer calories than you eat. By putting yourself in a daily deficit of 500kcals, you should in theory lose 1lb of fat.
Unfortunately, while this can work for some people, it’s not actually that simple.
Studies have shown that 3,500 calories largely overestimates how much weight someone will lose as well as how much of that weight will be from fat. Researchers explain that much of the discrepancy is because of the way the body’s metabolism. It changes as your weight changes. The weight you lose comes from a combination of fat and lean tissue, which is mostly muscle. How much of that weight loss comes from fat versus muscle depends on many varying variable, and caloric deficits never target fat exclusively. So when someone says you can burn fat exclusively on a new miracle diet or fat burning workout, it’s pretty much untrue.
To get a more accurate idea of your daily requirements, you can use an online metabolic rate calculator. These help you to calculate you basal metabolic rate (BMR), which refers to the number of calories that the body burns every day just to function effectively. It’s based on your height, weight, age, and gender, according to diabetes.co.uk. When multiplied by your daily activity factor, you get your daily energy output – if you were to take in the same number of calories each day you would maintain your current weight. You should also be mindful that some of these BMR calculators do not consider your body composition e.g. Two people weighing the same but one having more muscle will have a big difference between how many calories they burn on a daily basis.
you can create your own formula for weight loss. To put simply, as long as you eat and drink fewer calories than that number, or you increase your daily caloric burn with exercise, you will lose weight.
In terms of the 3,500-calorie rule, you would have to be in a daily deficit of 500kcals at the end of each day – resulting in losing 1lb of fat in a week. Unfortunately, that equation oversimplifies. As I have mentioned above there are varying factors to consider, so don’t expect to lose that much that fast.
You can use this link to predict your weight loss – weight loss predictor. It uses mathematical models based on your age, height, weight, and biological sex, as well as the size of your daily caloric deficit. It also provides an estimate of how many calories you need to maintain your body weight.
The larger your calorie deficit the faster you’ll lose weight. However, this does not mean that you should aim to create a huge deficit. In fact 80% of people who have successfully lost up to 10% of their body weight will gain back the weight they have lost over time. Faster is not always good. Experts typically agree that aiming for a weight loss of 1-2lbs per week is the healthiest and most sustainable pace of weight loss, if you are losing more than that in a given week, you are most likely eating into your muscle as well. This will result in lowering your BMR which sets you up to eventually regain the weight you lost, and possibly more!
If and when you are losing more than a couple of pounds per week, you’re also at a higher risk of not having enough macro-nutrients (protein, carbohydrates, and fat) or vitamins and minerals in your diet. When you cut calories to a point that rapid weight loss is possible, your overall food, and nutrient intake, can be unhealthily low. A study published in January 2018 in Nutrients analyzed three commercial diet plans designed to result in rapid weight loss, and authors reported that participants experienced deficiencies in nutrients such as vitamin D, B vitamins, vitamin E, selenium, and zinc. This can produce added complications to your body, such as hormonal imbalance, added stress, problems with sleep, low energy levels and problems with your mood.
Whatever your weight loss goal may be, diet and exercise should be part of the solution. Doing one without the other is setting yourself up to regain the weight later on. They complement each other. Yes, diet may have more of an impact in the immediate term, but exercise will be effective as a long-term sustainable solution.
Most people would find it easier to cut 500kcals from their diet than to burn 500kcals through exercise on a daily basis. But without the exercise, a there is going to be weight lost from your lean muscle, meaning that as you lose weight, your body-fat percentage could actually increase! By reducing your BMR you are setting yourself up for gaining more fat in the future.
One method you can use to keep track is to track your food through an app or keep a food journal. You could also use an activity tracker which will give you a more accurate reflection of how many calories you are expending on a daily basis – many people tend to overestimate just how little they are doing. If you are using a fitness tracker on considering buying one, just be mindful that they are not 100% accurate. What they do provide is a useful tool to keep you mindful. It pays to invest in a good quality tracker such as those provided by Withings.
My best advice, and the same advice I give to my clients is to implement small changes in your daily habits. Gradually introduce an increase in your activity and reduce your caloric intake by choosing healthier food and drink options. Practice mindfulness as well and if you are open to it you can try some visualisation meditation to help aid your journey. This can lead to slow, steady, and lasting weight loss.
Personally I workout five times per week, sometimes more if I have the time. Not all of my workouts involve going to the gym. Sometimes I will go cycling, hiking or even try a bit of yoga. The key is to make your journey enjoyable so that you can turn it into a lifestyle, and hopefully now that you know what it takes to lose 1lb of fat in a week, you’ll be able to take the necessary steps to a much more effective weight loss strategy.