Fitness trackers and food labels, have they stepped out of line?
Whether people are trying to lose excess weight or maintain their weight, they need to know the number of calories they are eating and the number of calories being used through exercise. Only then can they truly calculate their expected weight gain, weight loss or weight maintenance.
How can you count the calories you are eating and work out how many calories you are using?
Food composition tables, used in food labelling, is the mainstream method of calculating calorie intake, and fitness tracking devices for calories used. They both use simple maths, but will almost certainly give a very wrong result. Research demonstrates that both methods, relied on by the public and healthcare professionals, could be almost worthless.
Food Composition tables
The composition of almost any food item can be looked up in official books or searched online. These charts will detail what calories, vitamins, minerals and macronutrients the food consists of.
But how about the specific food sample you are planning to eat? Not just whether it is a beef burger but this particular beef burger on your plate.
All foods, previously living plants or animals, vary in their composition in the same way that people differ in their composition. For example we do not all have exactly the same level of muscle mass even though we share the same general physiology.
For food composition tables to exist, hundreds of samples of the same food, from avocados to beef burgers, have to be analysed and the results averaged. If you eat 100 beef burgers, you might get close to the amount of calories listed per 100 consumed, but a single beef burger is likely to have a different value to that listed in the food composition table or on the food label.
A wonderful study by Professor Jackie Stordy at Surrey University requested dieticians to plan a 1000 Calorie diet menu. Her graduate students purchased the foods and analysed them under laboratory conditions. They found an enormous variation between the samples, ranging from 1050 Calories up to 1600 Calories. Remember the menu was meant to be 1000 Calories, and so the poor soul attempting a 1000 Calorie a day programme, actually eating 1600 Calories per day would be very disappointed indeed.
It is essential that next time you study food labels, look at food composition tables, or rely on literature produced from commercial diets and books, you understand that you cannot be sure the calories stated is accurate. Use the food labels as a guide rather than as gospel.
Fitness trackers
Recent
research from Stanford University in California has shown fitness trackers, such as the FitBit Surge and the Apple Watch, to be so inaccurate they are potentially worthless.
The fitness tracker devices studied by Stanford University included 45 wrist-worn devices such as:
Apple Watch,
Fitbit Surge, Basic Peak, Alpha 2
Microsoft
Band, PulseOnMio, and the Samsung
Gear S2.
The researchers measured the heart rate (HR) and energy expenditure (EE) in a diverse group of 60 people. The group was subjected to a range of activities including walking, sitting and cycling. The effect on their heart rate and energy expenditure, the number of calories burnt, were then measured using various fitness devices and compared to that measured using detailed laboratory tests, including
continuous telemetry and indirect calorimetry.
Why measure heart rate (HR) and energy expenditure (EE)?
Physical health is the topic of our time. The NHS is making lifestyle advice and obesity intervention centre stage through the roll out of the new
National Diabetes Prevention programme (DPP). We are being constantly reminded on how the NHS is running out of money through our inability to be healthy; our smoking and drinking habits, and most notably our increasing waistlines.
Fitness trackers, in the form of wrist-worn devices, are currently perched at the top of many people's wish list, and worn for all to see. The
fitness market is currently worth £4.7 billion and technology is playing a big part in our attempts to improve our health.
Heart rate
Measuring heart rate gives a quick measure of the amount of work the heart is under. A person can have a "normal" resting heart rate within quite a range, generally between 60 and 100 beats per minute. If the heart rate is outside of these values for any prolonged time medical advice should be sought. A trained athlete may well have a heart rate of below 60 and someone with tachycardia will likely have a regular resting heart rate above 100.
On taking exercise the heart rate gives a measure of fitness level and also a measure of training intensity.
Heart rate is therefore a useful basic measure of health and fitness.
Energy expenditure
Measuring energy expenditure, the number of calories lost over time, is widely used to estimate the effectiveness of a persons weight management regime. Combining the HR and EE, using a fitness device, theoretically should allow for a tighter and more accurate assessment of any health improvement progress. Counting calories consumed or used up through exercise, is essential in all weight loss programmes.
The majority of weight loss programmes, designed for you or self imposed, will include a method of counting calories consumed (Food composition tables and food labels discussed above). Measuring the calories burnt is even more difficult and therefore many people are turning to fitness trackers that claim to provide this data.
What did the research on fitness trackers find?
Firstly the good news. The fitness trackers measured heart rate generally within the 5% leeway the researchers felt acceptable (walking showed the highest error in HR at just 5.5%).
The comparison of the results for HR between the fitness tracker and laboratory measurements means that, if you do use one of the wrist-worn devices you can be quite sure the readings are accurate whether you are an athlete or just managing your health or weight.
The bad news is that the measurements of energy expenditure, made by fitness trackers, overall was poor. None of the devices measured the energy expenditure within the target range of less than 5% error. Shockingly the error rates for measuring energy expenditure ranged from an error margin of 27.4% up to an embarrassing 92.6%.
It is also important to note that the results from the research into fitness trackers was under laboratory conditions. Real life use would predictably produce much worse results through changeable conditions and potential for the user of the device to not follow the manufacturers instructions fully.
What can we take away from this study on fitness trackers?
The results demonstrate the need for users, and more importantly healthcare providers, to proceed with caution when relying on, or recommending the use of, these wrist-worn devices for weight management purposes.
These devices should not be trusted as an accurate guide on the amount of calories burnt over a period of time. Using these devices for measuring heart rate however could be recommendable.
Exercising to lose weight
Travelling a mile, either by running or walking (remember
work done = force x distance) uses about 100 extra Calories (without consuming a sports drink). The number of calories to use up a single pound of body fat is 3500 Calories. It is important to remember that the calories taken from stored fat are only those necessary to make up the difference from the calories actually eaten. So if you are eating 1000 Calories and burning 2000 Calories a day, only 1000 Calories will be taken from storage. To lose a pound of fat weight, at that rate, will take 3.5 days.
It takes approximately 35 miles of exercise (3500 Calories divided by 100 Calories per mile moved) to burn off 1 pound of body fat. Wearing a dysfunctional fitness tracker may not help your assessment of your calorie burn, or in real terms, towards losing weight or maintaining your weight after weight loss.
Increased exercise levels in the UK are being encouraged as part of an overall strategy to prevent and treat the rising levels of excess weight. The NHS
Diabetes Prevention Programme is one such measure with exercise being employed to tackle obesity and type 2 diabetes in the UK. Hopefully it will be recognised that overweight people with disabilities, elderly people, or even seriously overweight and obese people, will not usually be able to do sufficient exercise to even make a dent in their excess weight.
Lipotrim has the solution
Lipotrim uses a bespoke computer programme to help pharmacies accurately measure the calories expended under real life conditions by a dieter. This method could be also be used to validate the performance and accuracy of fitness trackers. It is one of the outstanding features of dieting with Lipotrim. In addition to rapid, reliable and safe weight loss, sufficient to put type 2 diabetes into remission, it is possible to learn the actual daily calorie usage over a prolonged period of time. The Lipotrim results, predicting calorie usage, comes at no extra cost to the patient, and the whole programme at zero cost to the NHS.
This is a typical weight loss pattern of a compliant Lipotrim dieter. It is a plot of weight change over time, showing the drop in weight is continuous over each period of time. An accurate reading of kg weight loss per day can be read from the graph, and easily converted to Calories used up per day (conversion is 7700 Calories per kg).
The Lipotrim formula foods contain a fixed calorie intake per day. Any deviation from the diet and the resulting weight loss would no longer follow the straight line, as seen in this model example. If the person were to do more exercise, above that taken on an average day, the slope of the weight loss line will become steeper since more calories are used up.
Since the calories lost per day can be easily and accurately taken from the graph, by adding this output value to the calories consumed, which is fixed in the case of the Lipotrim dieter, the total maintenance calorie value can be calculated. The total maintenance calorie value is the number of calories that, if you strictly consumed just that amount per unit of time (no more, no less), body weight would be maintained. Eat more and weight will be gained, eat less and weight will be lost.
Pharmacies offering the
Lipotrim weight management programme have a powerful tool that saves the NHS enormous amounts of money, and offers reliable and substantial weight loss, sufficient to prevent and treat most cases of type 2 diabetes. We have also demonstrated Lipotrim could also provide evidence of the impact of exercise on the utilisation of calories.
Hopefully the
DPP will take note of the impact pharmacies are already having on this critical aspect of healthy living, despite the NHS having to deploy billions of pounds each year to achieve much poorer results.
There are times when pharmacies should not be invisible to the health authorities.
Lipotrim UK 0800 413 735
Lipotrim ROI 00353 (0) 1525 5636
The coronavirus has caused massive disruption throughout 2020.
