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A major study has highlighted the scale of the obesity problem in the UK, with a significant risk of death and disease attached to weight gain.

People with a body mass index (BMI) of 30-35 were at 70% higher risk of developing heart failure than their healthy weight peers (18.5-25 BMI).

The study of 2.8 million adults showed even slightly overweight people were twice as likely to get Type 2 diabetes.

Public Health England said "sustained action" was needed to tackle obesity.

The study, to be presented at the European Congress on Obesity (ECO) in Glasgow, also showed:

For those with a BMI of 35-40, the risk of Type 2 diabetes was almost nine times higher, and 12 times higher for sleep apnoea

People with severe obesity (BMI of 40-45) were 12 times more likely to develop Type 2 diabetes and had a risk of sleep apnoea that was 22 times greater

People with a BMI of 40-45 had triple the risk of heart failure, high blood pressure, and dyslipidaemia (abnormal levels of cholesterol and other fats in the blood)

BMI of 40-45 was also linked to a 50% higher risk of dying prematurely from any cause

The study's author, Christiane Haase, of healthcare firm Novo Nordisk which funded the work, said: "With the number of people living with obesity almost tripling worldwide over the past 30 years (105 million people in 1975 to 650 million in 2016), our findings have serious implications for public health."

BMI and obesity: Where are you on the UK fat scale?

Your browser does not support this lookup. Cannot retrieve data. Height cm Feet in cm ft/in Weight kg stone lb kg st/lb Age Age Gender Female Male Postcode Postcode Region Please choose Scotland Wales Northern Ireland the North East the North West the East Midlands the West Midlands Yorkshire and the Humber the East of England London the South East the South West Region Waist size (optional) i To measure your waist, find the bottom of your ribs and the top of your hips and wrap a tape measure midway between these points. Breathe out naturally before taking the measurement. Waist size (optional) Waist size (optional) cm in See how you compare Your BMI Your BMI is [bmi_result] which is in the [bmi_category] category. Healthy Overweight Obese Very obese Underweight 30 40 18.5 25 Healthy Overweight Obese Very obese Under- weight 30 40 18.5 25 BMI is a standard way of measuring if people are a healthy weight for their height. For most adults 18.5 to 24.9 is the healthy range. Your age group Your BMI is [comparative] the average of [bmi_score] for a [gender_singular] in your age group ([user_age_group]) in [user_country]. About [percent]% of [gender_plural] in your age group in [user_country] are overweight, obese or very obese. 0% Underweight 0% Healthy 0% Overweight 0% Obese 0% Very obese Your part of the UK In all parts of the UK, the majority of the adult population is overweight, obese or very obese, according to the latest national surveys. In [region], the figure is about [percentage]% of [gender_plural]. North East 50% West Mids 50% Scotland 50% East Mids 50% Yorks & Humb 50% N. Ireland 50% North West 50% South East 50% South West 50% East 50% Wales 50% London 50% 50% What does this mean for you? The information you've given us indicates you could be underweight. There can be health risks associated with a low BMI such as anaemia, osteoporosis, a weakened immune system and fertility problems. This is not a medical diagnostic tool so don't panic if this isn't the result you were expecting to see. If you're concerned about your weight, or your health in general, speak to a healthcare professional such as your GP. You're in the healthy range which is great. Research shows that having a healthy BMI can reduce your risk of serious health problems, such as type 2 diabetes, heart disease, stroke and some cancers. But not all people with a BMI in this range have a lower risk. Other factors such as smoking, high blood cholesterol or high blood pressure will increase your risk. If you're of Asian descent you have a higher risk of heart disease and diabetes at a lower BMI and waist circumference. A healthy BMI for you would be 18.5-23. We're more likely to gain weight as we get older so to stay a healthy weight you may need to make small changes to your diet or your activity levels as you age. The information you've given us indicates you are overweight. Research shows that a BMI above the healthy range can increase your risk of serious health problems, such as type 2 diabetes, heart disease, stroke, and some cancers. A healthy BMI for a person of your height would be 18.5-24.9. If you're of Asian descent you have a higher risk of heart disease and diabetes at a lower BMI and waist circumference. A healthy BMI for you would be 18.5-23. Losing even a small amount of weight, if sustained, can have a big impact. For most people changing your diet is by far the best way to lose weight. Activity can help you maintain your target weight, and can have other health benefits, but increasing activity alone is not nearly as effective as diet at helping you shed the pounds. Even small changes like reducing portion sizes or choosing lower calorie snacks and drinks can help you lose weight or stop putting it on. The information you've given us indicates you're in the obese category. Research shows that having a BMI in this range will significantly increase your risk of serious health problems, such as type 2 diabetes, heart disease, stroke, and some cancers. A healthy BMI for a person of your height would be 18.5-24.9. If you're of Asian descent you have a higher risk of heart disease and diabetes at a lower BMI and waist circumference. A healthy BMI for you would be 18.5-23. Losing even a small amount of weight, if sustained, can have a big impact. For most people changing your diet is by far the best way to lose weight. Activity can help you maintain your target weight, and can have other health benefits, but increasing activity alone is not nearly as effective as diet at helping you shed the pounds. There's lots of support available to help you make changes, either to lose weight or to stop putting on weight. The information you've given us indicates you're in the very obese category. Research shows that having a BMI in this range will significantly increase your risk of serious health problems, such as type 2 diabetes, heart disease, stroke, and some cancers. A healthy BMI for a person of your height would be 18.5-24.9. If you're of Asian descent you have a higher risk of heart disease and diabetes at a lower BMI and waist circumference. A healthy BMI for you would be 18.5-23. Losing even a small amount of weight, if sustained, can have a big impact. For most people changing your diet is by far the best way to lose weight. Activity can help you maintain your target weight, and can have other health benefits, but increasing activity alone is not nearly as effective as diet at helping you shed the pounds. If you are concerned, or would like to find out more, speak to your doctor or GP. If you are ready to make lifestyle changes, there is lots of support available. Your waist size BMI is not the only way of measuring whether you are a healthy weight. Doctors say that carrying too much fat around your belly can increase your risk of health problems. Excess fat in this area can stress internal organs - even if your BMI is in the healthy range. Your waist size is [size] For [gender_plural], the NHS says a waist size of: 80cm (31.5 inches) or more means an increased risk of health problems 88cm (34 inches) or more means a very high risk of health problems 94cm (37 inches) or more means an increased risk of health problems 102cm (40 inches) or more means a very high risk of health problems People from non-white ethnic groups may be at risk at a lower waist size How to check your waist with just a piece of string

We calculate BMI using the standard formula of a person's mass in kg divided by the square of their height in metres (kg/m2) and display it to one decimal place.

Where a user's data is entered in imperial units, we first convert to metric and then carry out the BMI calculation.

The BMI result is assigned to a standard category:

Less than 18.5 - underweight

18.5 to 24.9 - healthy weight

25 to 29.9 - overweight

30 to 39.9 - obese (split into two categories for the new study)

40 and over - very obese (also known as morbidly obese)

The research found that the risk of developing serious health problems was highly dependent on whether or not people already had issues at the start of the study.

For example, having high blood pressure at the start of the study was strongly associated with developing dyslipidaemia, chronic kidney disease and Type 2 diabetes.

Researchers looked at health, death and BMI data from more than 2.8 million adults between January 2000 and July 2018 from the UK Clinical Practice Research Datalink.

This was linked with hospital data to estimate the risk for serious health problems.

But the authors stress that their findings show observational differences, so no firm conclusions can be drawn about cause and effect, and they point to a number of limitations:

the study participants must have seen their doctor and had their weight measured for a reason

other, unmeasured factors may have influenced the results

Victoria Taylor, nutrition lead at the British Heart Foundation, said: "More than a quarter of UK adults (28%) are obese and it's something that we urgently need action on."

Novo Nordisk manufactures medications for Type 2 diabetes.