What is the NowPatient BMI Risk Service?
The BMI Risk Service is a clinical tool used to assess healthy weight in adult men and women. A healthy weight is defined as a value linked to a lower risk of weight-related diseases and health conditions. Unlike traditional BMI calculators that only use height and weight, the NowPatient BMI Risk Service is an advanced measure that also takes into consideration other parameters such as your age, sex, waist size, and ethnicity. For example, if you are from a black and ethnic minority group, you are at increased risk of type 2 diabetes with a BMI of 23 or more.
How is the NowPatient BMI Risk Service different from a standard BMI calculator?
Most BMI calculators stop at height and weight. The NowPatient Advanced BMI Assessment goes further and combines BMI with age, sex, waist size, and ethnicity to deliver a personalized health risk score that actually means something. It also tracks your metrics over time, alerts you when your risk level changes, and if action is needed, can automatically qualify you for support through NowPatient’s Weight Loss Programs Service.
Is the BMI Risk Service free?
Yes. The BMI Risk Service is a free service available to all registered NowPatient users.
Is the BMI Risk Service a medical device?
Yes. The BMI Risk Service is classified as a Class I medical device under UK MDR 2002 regulations for its intended use.
Where do I find the BMI Risk Service in my account?
Navigate to the ‘Personalised Insights’ section of your account homepage. The BMI Risk Service Card will be displayed there. If you completed your Health Profile when you first created your NowPatient account, your score will already be calculated and visible. If not, the card will appear locked — select the ‘Unlock’ button and complete the questions in your health profile to activate it.
What information is used to calculate my BMI Risk Score?
The BMI Risk Service uses the following special category data from your Health Profile:
Age
Height
Weight
Ethnicity
Waist size
What do the BMI Risk Scores mean?
The table below explains each BMI category and the recommended actions:
How will I be notified about my BMI Risk?
The BMI Risk Service identifies and classifies health risks. NowPatient’s AI algorithms trigger warnings based on your BMI Risk Score. You will receive two types of personalised alerts — one based on your BMI score and one based on your waist readings. If the algorithm identifies a risk, you will receive a push notification with clinical advice on what to do next, sent directly to your device, as well as an In-App notification viewable in the ‘Notifications’ section of your account homepage. You can also view any warning advisory by selecting the ‘View Warning’ button on the BMI Risk Service Card.
How do I update my BMI Risk Score?
Update your Health Profile monthly and before any NowPatient Service Consultations you may book. Updated information may affect your BMI Risk Score, which will be reflected as an updated score on the Service Card, allowing you to track the benefits of any lifestyle or medication interventions over time.
Why does NowPatient ask for my waist size?
Although waist size is not used directly in the NowPatient BMI Risk calculation, it is an important additional health indicator. Carrying too much fat around your stomach can raise your risk of heart disease, type 2 diabetes, and stroke — even if you have a healthy BMI. The BMI Risk Service uses your waist size to generate a separate waist risk alert distinct from your BMI score.
What are the waist size thresholds I should be aware of?
If your waist size is above the following thresholds, it means you are carrying too much fat around your stomach which can raise your risk of developing heart disease, type 2 diabetes, and stroke. NowPatient recommends that you try to lose weight:
>94cm (37ins) for men
>80cm (31.5ins) for women
If your waist size exceeds the following thresholds, it means you are carrying too much fat around your stomach which can raise your risk of developing heart disease, type 2 diabetes, and stroke. You have a very high risk of developing long-term health conditions. You should make an appointment with your GP:
>102cm (40ins) for men
>88cm (34ins) for women
How do I measure my waist size correctly?
According to WHO guidance, waist circumference should be measured:
At the midpoint between the lower margin of the last palpable rib and the top of the iliac crest
With you standing, arms relaxed at sides
At the end of a normal expiration (breathing out)
Using a non-elastic measuring tape held snugly without compressing the skin
NowPatient recommends measuring your waist at the same time of day each month — for example, first thing in the morning — for the most consistent results.
Step 1 At the midpoint between the lower margin of the last palpable rib and the top of the iliac crest
Step 2 With you standing, arms relaxed at sides
Step 3 At the end of a normal expiration (breathing out)
Step 4 Using a non-elastic measuring tape held snugly without compressing the skin
How will I be notified if my waist size indicates a health risk?
NowPatient’s AI algorithms trigger warnings based on your waist readings. If the algorithm identifies a risk, you will receive a push notification with clinical advice on what to do next, sent directly to your device, as well as an In-App notification viewable in the ‘Notifications’ section of your account homepage. NowPatient advises all users to update waist readings monthly and also before any NowPatient Service Consultations booked.
What should I do if my score puts me at risk of developing long-term conditions?
If the BMI Risk Service classifies you as being ‘at risk’ of developing long-term health conditions, you can raise this with your doctor at your next appointment. NowPatient may also automatically qualify you for risk-reducing strategies such as the Weight Loss Programs Service. You will be notified if you are eligible.
Can I use the BMI Risk Service if I have an eating disorder?
No. If you have an eating disorder, the BMI Risk Service should not be used. Please get further advice from your doctor or other healthcare professional.
What are the limitations of the BMI Risk Service?
The BMI Risk calculation does not factor in muscle mass, which is denser than fat. As a result, muscular adults and athletes may be classified as overweight or obese despite having low body fat. Conversely, older adults who lose muscle may fall within the healthy weight range even if they have excess body fat.
Additionally, the BMI Risk calculations should not be used for pregnant individuals, as pregnancy-related weight changes can affect accuracy.
Is the BMI Risk Service a diagnostic tool?
No. The BMI Risk Service is a clinical screening and monitoring tool, not a diagnostic service. It identifies risk levels that warrant a conversation with your doctor, who can order appropriate tests and recommend the most suitable interventions for your individual circumstances.