Best BMI for Adults With Type 2 Diabetes Varies by Age
Author: European Association for the Study of Obesity
Published: 29 Mar 2024 - Updated: 4 Nov 2026
Publication Details: Peer-Reviewed | Reports and Proceedings
Table of Contents:
Synopsis - Definition - Overview - FAQs - Insights, Updates - Related Content
Synopsis
This research, presented at the 2024 European Congress on Obesity in Venice, used UK Biobank data on 22,874 adults with type 2 diabetes followed for nearly 13 years, during which 891 died of cardiovascular disease. For people aged 65 or younger, a BMI of 23 to 25 was linked to the lowest risk of cardiovascular death, and being overweight carried a 13 percent higher risk than normal weight. For those over 65, a BMI of 26 to 28 had the lowest risk, and being overweight was linked to an 18 percent lower risk. The findings matter to older adults with diabetes and their doctors, who may set different weight goals by age.*
At a Glance
- 1 - The average age of participants was 59, and about 59 percent were women.
- 2 - The optimal BMI cut-off was 24 for the middle-aged group and 27 for the older group.
- 3 - Most UK Biobank participants are White, so the results may not apply to other ethnic groups.
- 4 - Larger waist size and waist-to-height ratio were linked to higher cardiovascular death risk at all ages.
Topic Definition
- Obesity Paradox
The obesity paradox is the observation that, in some groups such as older adults or people with certain chronic diseases, those who are overweight or mildly obese have lower death rates than those of normal weight. Proposed explanations include greater energy reserves during illness and protection of bone and muscle, as well as limits of BMI as a measure, and researchers continue to debate how much of the effect is real.
Overview
New research presented at the 2024 European Congress on Obesity (ECO) in Venice, Italy (12-15 May, 2024), identifies the optimum body weight range for adults with type 2 diabetes to minimize their risk of dying from any cardiovascular disease, including heart failure, heart disease, stroke, and chronic kidney disease.
The findings, based on health data from the UK Biobank, indicate that for adults aged 65 years or younger, maintaining a body mass index (BMI) within the normal range of 23-25 kg/m² was associated with the lowest risk of dying from cardiovascular disease. But for those over 65 years old, being moderately overweight with a BMI of 26-28 kg/m², had the lowest risk.
Maintaining a healthy weight is crucial for reducing the risk of cardiovascular diseases, particularly for people with type 2 diabetes who are predisposed to cardiovascular disease and death. However, it's not clear whether the optimal BMI range for people with type 2 diabetes varies by age.
To plug these knowledge gaps, researchers explored the age differences in the association between BMI and risk of cardiovascular death in 22,874 UK Biobank participants with a previous diagnosis of type 2 diabetes at the time they enrolled between 2006 and 2010. Patients with prior cardiovascular diseases were not excluded.
The average age of all the participants was 59 years, and around 59% were women. Their cardiovascular health was tracked, using linked health records, for nearly 13 years during which time 891 participants died from cardiovascular diseases.
Analysis
Researchers analyzed data in two age groups - the elderly (over 65 years) and the middle-aged (age 65 years or younger) - and assessed the relationship between variables such as BMI, waist circumference, and waist-to-height ratio and the risk of cardiovascular death.
The optimal BMI cut-off point was also calculated in different age groups and the findings were adjusted for traditional cardiometabolic risk factors and other factors associated with adverse cardiovascular outcomes including age, sex, smoking history, alcohol consumption, level of physical exercise, and history of cardiovascular diseases.
The analyses found that in the middle-aged group, having a BMI in the overweight range (25 kg/m² to 29.9 kg/m²) was associated with a 13% greater risk of dying from cardiovascular disease than those with a BMI in the normal range (less than 25.0 kg/m²).
However, in the elderly group, having a BMI in the overweight range (25 kg/m² to 29.9 kg/m²) was associated with an 18% lower risk of dying compared to having a BMI in the normal range (less than 25.0 kg/m²).
The relationship between BMI and cardiovascular death risk exhibited a U-shaped pattern, even after stratification by age, so the optimal BMI cut-off point was different in the elderly and middle-aged groups. For the middle-aged group, the optimal BMI cut-off was 24 kg/m², whereas for the elderly group, it was 27 kg/m². Consequently, personalized treatment plans can be developed in clinical settings by tailoring recommendations to different age groups.
The researchers also found a positive relationship between both waist circumference and waist-to-height ratio and the risk of cardiovascular death. As waist circumference increased, the risk of cardiovascular death also showed a corresponding rise. When the study population was divided into older and middle-aged categories, this upward trend remained consistent. Similar patterns were observed for the waist-to-height ratio. However, no significant BMI cut-off point was identified.
"Importantly, we demonstrate that optimal BMI for people with type 2 diabetes varies by age, independent of traditional cardiometabolic risk factors", says lead author Dr Shaoyong Xu from Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, China. "Our findings suggest that for older individuals who are moderately overweight but not obese, maintaining rather than losing weight may be a more practical way of reducing their risk of dying from cardiovascular disease."
He adds:
"Our findings also indicate that adiposity may offer some protection against fatal diseases to some extent. The possible biological mechanisms that explain this 'obesity survival paradox' in elderly people may be associated with a lower rate of bone mass loss, which reduces the effects of fall and trauma episodes, and greater nutritional reserves to accommodate periods of acute stress."
The authors say that in the future, measures of central obesity, such as waist circumference, would be used to further refine the risk.
The Research
This is an observational study, and as such, can't establish cause. And the researchers acknowledge various limitations to their findings, including small numbers of cardiovascular deaths and no information on type of cardiovascular disease or specific treatments. They also note that most of the UK Biobank study participants are White, so the findings might not apply to people of other ethnic backgrounds. Also, the nature of the cohort study may create potential classification errors that could partially affect the conclusions, because anthropometric measurements were only assessed at the start of the study, and body weight may change during the follow-up period.
COI Statement
Shaoyong Xu and Ke Wang organized the funding for the study which was supported in part by several sources. These included the Young Talents Project of Hubei Provincial Health Commission China, Hubei Provincial Natural Science Foundation of China, the Science and Technology Research Key Project of the Education Department of Hubei Province China, and the Sanuo Diabetes Charity Foundation China and the Xiangyang Science and Technology Plan Project China.
Frequently Asked Questions
NOTE: Researched FAQs by Disabled World (DW)
What is a healthy BMI for older adults?
Some research, including this study, suggests a slightly higher BMI may be linked to lower death risk after 65, but targets should be set individually with a doctor.
Should older adults with diabetes lose weight?
Not always. For some older adults, keeping a stable weight and preserving muscle may matter more than weight loss. A doctor can advise.
Why is waist circumference important in diabetes?
Fat around the abdomen is closely linked to insulin resistance and heart disease, so waist size can signal risk even when BMI looks normal.
What is the UK Biobank?
It is a large research database holding health, lifestyle and genetic information from about half a million UK adults recruited between 2006 and 2010.
How does type 2 diabetes affect heart health?
High blood sugar damages blood vessels over time, raising the risk of heart attack, stroke, heart failure and kidney disease.
Can losing muscle with age affect diabetes control?
Yes. Muscle helps use blood sugar, so losing muscle can worsen control. Strength exercises and enough protein help preserve it.
Is this study proof that extra weight protects older people?
No. It is observational and measured weight only once, so it shows a link rather than cause and effect.
What is waist-to-height ratio?
It is waist size divided by height. A ratio above 0.5 is often used as a sign of higher health risk.
Insights, Analysis, and Developments
Editorial Note: Weight advice for people with type 2 diabetes has usually been the same at every age, but this study suggests that after 65 a little extra weight may be protective, possibly by providing reserves during illness and cushioning falls. Waist size, on the other hand, mattered at every age. As an observational study with weight measured only once, it cannot tell people to gain or keep weight, but it supports a more individual approach. Older adults with diabetes, especially those with frailty or disability, should discuss weight targets with their doctor rather than following general rules.*
Attribution/Source(s): This peer-reviewed publication was selected for publishing by the editors of Disabled World (DW) due to its relevance to the disability community. Originally issued as a press release by European Association for the Study of Obesity and published on 29 Mar 2024. Last updated on 4 Nov 2026. This content may have been edited for style, clarity, or brevity.
* Editorial additions by Ian C. Langtree.