I like to take measurements of clients and help them understand what that can tell them about their health. I use them to create realistic targets that make a difference. Here’s a summary of what I look for. Do you measure up?
The Body Mass Index (BMI) is one indicator of your body size in relation to health. It takes your weight in kilograms and divides it by your height (in meters) squared. Scores 19-25 are a healthy weight, over 25 overweight and 30 and over obese. But it doesn’t account for the fact that muscle weighs more than fat. So your build matters, some muscular people may have a high BMI but because they have a high proportion of muscle to fat. Likewise, it may underestimate fat in older people or those who’ve lost muscle. It’s fat and where it’s at that’s important.
Tummy Fat Matters
Where your fat is stored around your body matters. When it sits around the middle it is more likely to be dangerous visceral fat, compared to fat on hips and thighs. This is ‘active’ fat and not just stored energy. This fat releases chemical messengers and hormones which act to increase the risk of heart disease, stroke, type 2 diabetes and some cancers.
A far better predictor of health is to measure your waist circumference as an indicator of how much fat is stored around the middle. To measure your waist feel for your bottom ribs and then feel for your hip bones, take a tape measure and measure straight across half-way between these 2 points. This is usually about 2” above your navel.
Half your Height
A rule of thumb is that your waist measurement should be less than or equal to half your height. So someone 5ft 10” tall should have a waist no more than 35” (5ft is 60” so use this to do your own calculation). An Australian study showed that when the BMI is over 30 (obese category) waist size is likely to be too high (excluding very muscular people) so the BMI is a quick first calculation to do. For more detail on healthy waist ranges see this link.
Body Fat Percentage
It is difficult to measure how much of your fat is visceral (around the central organs in your middle) although ultrasound is reliable it is rarely used. Taking your body fat percentage can be another useful calculation. This can be done with body fat callipers with an average taken over several sites, and the individual measurements can give you an idea of how the fat is distributed. Many gyms and personal trainers used to use these. Bio impedance machines can be convenient. Look for these machines in gyms and pharmacies that look like robust scales and you usually pay to get your weight and a breakdown of your body fat. They are best used to monitor changes rather than to take a one-off figure but can still be a useful guide. A healthy level for 40-59 year old women is 23-34% and for the same age group of men is 11-22%. For Body Fat Percentage Ranges by Sex and Age see this link.
Take Measurements Regularly
Know what the scales say, measure your waist and use a body fat analyser machine or callipers, and note down all these figures. Take regular readings choosing the same day of the week, same time of day, with the same equipment, under the same conditions. For body fat readings being normally hydrated is important (do not measure after a gym session).
Other Risk Factors
There are other risk factors (and numbers) that count. Do you know your blood pressure? Have you had your blood glucose checked? Are you a smoker? I recommend all my patients 40 years and above get the free NHS Health Check which includes blood pressure and blood glucose measurements as well as looking at the fats in the blood. See this link. I often write to doctors to get blood tests for other patients when I think this is helpful.
Lose Weight lose Tummy Fat.
A weight loss of 5-10% of your starting weight improves your health. I use a 5% weight loss target for clients. So if you are 12 stone losing just over half a stone (and keeping it off) makes a difference to health. And often the abdomen is the first place fat loss occurs. It is generally accepted that visceral fat reduces at a greater rate because it is more active metabolically and breaks down quickly.
So, measure up and use those figures to take control of your health.