It seems like everyone is ‘on a diet’ and it’s no wonder with newspapers regularly reporting about the ‘obesity epidemic’ and magazines full of the latest weight-loss tips. But how do you know if you really need to lose weight?
Human beings come in all sorts of shapes; there is no perfect weight or size that suits everyone. There are ways that you can measure body-fat percentages, which can give you an idea of whether fat stores are too high to be healthy. These can be unreliable though, like those handheld devices that send an electronic current through your body (my body-fat percentage changed by around 5% in a day or so…hmm!). Or they can be invasive; the skin-fold measurements involve pinching skin using a pair of callipers –accuracy can be an issue depending on the person doing the measuring. The more accurate methods tend not to be readily available to the general public.
So what do we do?
Although not 100% accurate, the Body Mass Index (BMI) is the best way of giving you a rough idea of whether you need to have a look at your eating and exercising habits. If you struggle to get to grips with it then here’s my guide to understanding it a little better.
What is the BMI?
To give you the simple explanation the BMI gives you an idea of your weight in comparison to your height. The taller a person is, the more they would expect to weigh as there is more of them. To work out your BMI there is a simple equation: w÷h2 or weight (in kilograms) divided by height (in metres) squared. So you would need to convert your weight and height into metric – most phones have a converter or you can search on the Internet. Then start by finding your height squared e.g. if you were 1.65m tall then you would multiply 1.65 by itself (1.65×1.65) to find 2.7225. Then if you weighed 75kg you would divide 75 by 2.7225 to get 27.5kg/m2 (rounded to one decimal place) – giving you a BMI of about 27.5.
There’s an easy BMI calculator on the NHS website, with lots of info too – click here.
So what do the numbers mean?
|BMI||What does this mean?||How does this affect my health?||What should I do?|
|Less than 18.5||Underweight||You may be at risk of health problems such as osteoporosis (fragile bones), weakened immune system or fertility issues.||Try to make sure you are eating regular, balanced meals. You could seek help from a registered Dietitian if you need support gaining weight and checking the balance of your diet.|
|Between 18.5-25||Healthy weight||Your weight is considered healthy for your height. You have a lower risk of developing health conditions such as diabetes than someone considered overweight.||Aim to maintain your weight. Try to follow a healthy balanced diet and look at your activity levels. Aim for around 2-3 hours of exercise each week and try to limit the amount of time you are sat still.|
|Between 25-30||Overweight||You may be at an increased risk of developing health problems such as diabetes, heart problems or stroke.||You may want to consider losing some weight unless you have already lost a significant amount recently (around a stone) – in which case well done, you have already helped improve your health! Think about what is realistic for you. Look at your eating and exercising habits and try to make a few changes that you can stick to forever, not just until you have lost the weight.|
|Above 30||Obese or very overweight||Being obese or very overweight increases your risk of developing diabetes, heart problems or stroke. You may find daily activities more difficult than if your weight was lower and you could be adding strain to your back and other joints.||It would be a good idea to try to lose some weight to improve your overall health. Aiming to lose around 5% of your weight could significantly reduce your risk of health problems, even if you are still classified as overweight or obese.|
(If you think you may have an eating disorder, speak to your GP to get referred for proper advice and support)
Now there are a couple of issues with the BMI. For example it doesn’t take into account if you have a high muscle mass, which you are likely to have if you’re very active e.g. through weight-training. Some professional athletes e.g. rugby players, would have a BMI in the overweight classification, but nobody would doubt that they are very healthy. In this instance there is another measurement you can look at – your waist circumference. Research shows that having a high waist circumference is associated with an increased risk of developing diabetes. You can find out more information here.
Another issue with the BMI is that if you are from Black, Asian or other ethnic minority groups, you may still be at an increased risk of some of the health problems even with a BMI below 25 – again it’s worth looking at your waist circumference measurement in this case.
After working with many clients over the years with BMIs of 30, 40 and beyond, I’ve found a lot of people actually started out being a healthy weight or just a little overweight. The problem starts when they decide to follow the latest fad diet in order to lose weight, instead of making life changes. Clients have told me time and time again about how they’ve tried it all and the diets all work wonders, but only while they continue to follow the diet. As soon as they ‘come off’ the diet the weight goes back on again, usually with a little more. Gradually they yo-yo up and down and up again, until they suddenly find themselves much bigger than when they first started. In this case they would’ve been much better off aiming to maintain their original weight, even if they were a little overweight.
If you are considering losing weight for the first time – take some time to assess how you are going to do it. Are you committed to making a few changes for life or are you just following a plan for a set amount of time? Which do you think will work best? Is your goal really realistic for you? If you are trying to lose weight, because you have gained some recently – try to focus on why you have gained weight rather than following a drastic diet plan. Overall it may be healthier to aim to maintain a BMI of around 26-27 rather than yo-yoing between a healthy BMI and one of around 30.
If you feel stuck in the yo-yo dieting cycle and want help breaking free once and for all, get in touch to book your assessment and let me show you how I’ve helped clients to take back the control over their weight. No diets, no expensive products, just normal foods including the treats you love – click here.
If you’re struggling to get yourself motivated to get going on managing your weight – check out my FREE e-book ‘Your Guide to Self-motivation’ – click here to get your copy.