Do we have an ideal weight and does it really matter?
From a medical view the answer is yes to both.
In a small percentage of us being underweight is an issue. But for most of us the problem is pointing in the other direction - the latest statistics in Australia indicate that 60% of adults are overweight or obese and with our kids we're looking at 25%. And the percentages are rising each time they do a survey. So if you are overweight - don't worry since you're not alone! Let's tackle the second part of the question first - why does it matter?
The reason this classification exists is to estimate the risk of developing health problems. People who are overweight have a greater risk than others of developing heart disease, diabetes, kidney disease, musculoskeletal problems, cancer and there is even a strong link between being overweight and depression. It used to be the case that the only thing overweight people had going for them is that they had a higher bone density than others, but now this trend is going the other way. The theory is that many people who are overweight struggle to exercise and can drink more carbonated soft drinks than others and both of these factors reduce bone density.
Even some people who suffer from an eating disorder have been overweight at some stage in their life and the main issue for them is fluctuating weight due to rapid changes in eating, exercise and unhealthy practices.
At some stage in our lives we're all going to feel that looking after ourselves is not the first priority. This can be because you need to or choose to deal with more urgent issues, such as looking after someone else in your family who has health issues, working those extra hours due to financial pressures, studying for an exam and let's face it - life shouldn't always be about us! This period in our lives could only be a week but it could be months, years or decades. I worked in a surgical weight loss clinic for 5 years and some of the patients there were the way they were because they were selfless - they felt that their loved ones were more important. But when our weight means we become a burden on people around us we need to have a rethink. And when we do decide that we need to look after ourselves it can be a very difficult road to get back to where we once were.
Unfortunately our body has a WEIGHT MEMORY. This means that it remembers the biggest we've ever been and will do almost anything to maintain or get back to that weight or even get higher. If we diet too quickly it will activate a starvation response so our basal metabolic rate slows down, we feel more tired so we move less and conserve energy, we feel more hungry so we eat more and it basically hurts! As we get older our body becomes more efficient at conserving energy and putting on weight. Plus we don't run around like spring chickens like we used to do as kids. I'm the same height I used to be when I was 15 years old - I estimate though that I eat probably 75% less food than I did when I was that age. However I'm 19kg heavier! No wonder I get so puffed when I run! It only gets harder as you get older!
So all of this means that if you are overweight it is very difficult to get back to your ideal weight - the longer you leave it the harder it will be. You have to try really hard - probably for the rest of your lives - and it will hurt.
So how do we know we are overweight? There are many ways - some of these involve expensive body composition machines and there are also the bioelectrical impedance "fat scales" which are becoming cheaper. What we are trying to do is actually calculate how much excess fat we have - since the stuff around our bellies is generally what causes the health problems. And for most of us out there our excess weight is all fat, rather than muscle. There are two easy ways:
1. Waist circumference - you can get a tape measure and measure your tummy all the way around! Between your ribcage and your hip bone (iliac crest) when you are breathing out. If you are an adult male you want to be less than 94cm and females less than 80cm. They used to ask people to measure where their belly button was but this can be in strange places in some people! Some people feel this is the most accurate way to assess how much fat we have around our bellies.
2. Body Mass Index (BMI) - measure your weight in kg and divide by height squared in metres. (wt/ht2). This will be high in some very muscly people such as bodybuilders but if you are not an elite athlete then it's a fairly accurate guide to how healthy your weight is. If you are an elite athlete it might be worth instead having your composition assessed by a DEXA scan or having your skin folds measured. The WHO (World Health Organisation) recommends the healthy weight BMI being 18.5 - 25. If you are 25 - 30 then you are overweight and if you are over 30 then you are obese. Now this is just for adults and there are different recommendations for certain racial groups - Asians, Indians and Indigenous adults should be a bit lower than this, and Pacific Islanders can be a bit higher. With kids using BMI is accurate but to know if you are in the ideal weight range you need to plot it on a graph - you can find one here.
Some of you might be saying - I'm just a big build - my whole family are and I was born this way. This may be true but it is also true that you will have more health problems being bigger than you should.
For some of you this may all sound very depressing but we should all face the realities because one day they will look at us right in the face anyway. In future blogs I hope to explore different ways to eat and exercise so that you find a way which works for you to enable you to reach your goals!
do you remember the study of arly mortality rates in Britain which showed that fat and exercising was better than skinny and non active? Longitudinal study with 33,000 subjects.
Well Jules - are you sure the researchers weren't overweight since that is the sort of thing that overweight people say - hahaha - just kidding! Certainly you are right in that more and more people are realising that activity alone has great health benefits whether it is related to your weight or not - it is really interesting stuff and in particular how harmful to our health sitting is. So the birth of the treadmill desk, etc.. But that is for another time. As is the harmful benefits to your health of poor sleep and also stress, There is heaps we can discuss in this blog. The problem that I am concerned about is how many people are kidding themselves in this day and age thinking that they are doing OK when they could be feeling much better and have a better quality of life by just losing a few kilograms. The largest medical studies on syndrome X - that is obesity, high blood pressure, high cholesterol and diabetes - have always come out of the UK and in particular parts of Scotland where there are high rates of unhealthy eating, smoking and inactivity - and I'm just talking about the doctors!
We understand that obesity (amongst many other conditions)leads to increased angiogenesis and therefore increased blood volume which can contribute to hypertension, plus increased loading on joints leading to arthritis etc. What about athletes that have greatly increased muscle mass for example powerlifters(with whom I work a lot ) would their increased body mass also potentially lead to hypertension and joint damage?
Yes Colin - definitely. The larger body mass leads to increased total peripheral resistance so blood pressure is higher. The body can keep it down when you are young but then one day it just stops being able to compensate and it starts rising. They used to tell us to give some slack with blood pressure to older people and taller people and athletes but studies still show they suffer from the detrimental effects of this such as higher risk of heart disease, strokes and kidney damage - so now we're not meant to be so lenient! The joint damage certainly is there because of the higher weight. Obviously with powerlifters there is also the increased load on certain joints such as the patellofemoral joint in the knee from deep squats and the ac joint from overhead weights. It's not all bad news for these guys though since they rarely suffer from long term back issues - they could have pathology on scans but control not much pain. Perhaps when you have a huge weight on your shoulders you don't have much choice but to stay in good neutral alignment.
Many thanks Wilson for your comprehensive reply. Since BMI is unreliable for more heavily muscled athletes how should powerlifters calculate an ideal bodyweight?
Colin, Most athletes look at power to weight ratios so that is one reason for them to minimise body fat. As doctors we just look at long term health, so when I discuss ideal body weight I'm really targeting minimising visceral fat - so the fat around the liver and other abdominal organs. That's the stuff that leads to long term issues. So if a powerlifter wants to increase the power to weight ration then have a look at DEXA scans or get a professional to measure skin folds. If they are interested more in long term health and reducing risk factors for disease then the simple tape measure around the waist will do.
Most of us out there aren't athletes though and I think shouldn't be fooled by the firmness of the tummy! I saw this because many men in particular comment that most of their abdomen is muscle because the "beer gut" feels firm. Professor Gary Egger of Southern Cross University explained that there are 3 layers of fat in the abdomen - if you fill up each layer it feels firm rather than flabby. So a firm "beer gut" is just heaps of fat compressed. Of course women tend to put on fat in other areas such as hips, thighs and arms. So even though excess weight in those areas can wear out the joints, it is not so damaging to the organs.