New Zealand GP explains 'why healthy people still have heart attacks': Normal BMI but excess visceral fat...

Dr Brad Stanfield warns hidden visceral fat can drive chronic disease, even in people with a normal BMI – so try this one thing to get a clearer picture.

A reliance on Body Mass Index (BMI) alone to assess heart health risk could be giving millions of people a false sense of security, warned New Zealand-based general practitioner, Dr Brad Stanfield, in a November 16, 2025 video on his YouTube channel.

Here's why shedding the extra belly fat can cut your heart disease risk. (Freepik)

Dr Stanfield explained that a critical metric — visceral fat, commonly known as 'belly fat' — is often overlooked but acts as a powerful, independent driver of chronic inflammation and disease. “You think you've done a wonderful job with your health... your BMI is exactly where it should be... but then you have a heart attack two months later. How on earth does that happen?” Dr Stanfield asked in the video.

He explained that people can have a normal BMI yet carry dangerously high levels of visceral fat around their internal organs, placing them at significantly heightened risk for conditions like type 2 diabetes, high blood pressure, and stroke.

The BMI blind spot: visceral fat's hidden danger

While BMI has a well-established link to negative health outcomes, Dr Stanfield said that not all fat is created equal. He spoke about subcutaneous fat (fat stored just under the skin) and said it does not have the same strong link to disease. However, visceral fat (fat stored deep around the heart, liver, and other organs) was strongly associated with chronic inflammation, which was a key driver of heart disease, he added.

Dr Stanfield said, “Interestingly, subcutaneous fat doesn't have the same strong link with conditions like type 2 diabetes as visceral fat, which is strongly associated with it. Similarly, chronic inflammation associated with obesity is primarily driven by visceral fat. And that's why BMI alone doesn't tell us everything that we need to know.”

“It's possible to have a normal BMI while also having excess visceral fat, resulting in the classic 'bear belly.' I'm sure you know someone like this. Someone who's basically lean everywhere except their stomach, and men in particular, that's usually because of excess visceral fat,” he explained, noting that this was often due to the fat type that doctors too often forget to check: waist circumference.

Study reveals risk for 1 in 5 adults

Dr Stanfield highlighted a new study that examined data from the World Health Organisation, covering nearly 470,000 participants across 91 countries. The researchers focused on individuals with a normal BMI (18.5 to 24.9) but a high waist circumference, he said. Dr Stanfield shared that the key thresholds for high waist circumference were:

⦿ Women: 80 cm (31.5 inches) and above

⦿ Men: 94 cm (37 inches) and above

According to Dr Stanfield, the study's findings for this 'normal weight, high visceral fat' group were sobering:

⦿ Type 2 diabetes — 81% higher risk

⦿ High blood pressure — 29% higher risk

⦿ High total cholesterol — 40% higher risk

⦿ High triglycerides — 56% higher risk

The data revealed that approximately one in five adults in the global dataset fit this description, a combination the researchers called a ‘huge problem on our hands’ because most global guidelines rely solely on BMI, the doctor said.

Take charge of your health

Given that this critical metric was often missed in clinical settings, Dr Stanfield provided simple, practical instructions for self-assessment:

⦿ Stand up and locate the top of your hipbone at your side.

⦿ Measure just above that level using a flexible tape measure.

⦿ Measure at a normal breath (do not suck your stomach in).

Dr Stanfield said that checking your waist circumference at home in this manner was just as accurate as a clinical check, empowering people to 'take charge of our own health'. He added: “The good news is that it's entirely possible to lose that extra visceral fat, and as we've seen, when we do, we also reduce our risks.”

Note to readers: This report is based on user-generated content from social media. HT.com has not independently verified the claims and does not endorse them.

This article is for informational purposes only and not a substitute for professional medical advice.