In the last few weeks FoodFacts.com posted information from a study that claimed that for certain people obesity might not have long-term health implications. The concept of “healthy obesity” has become an actual theory among some researchers and some in the general population.
But now a new study shows that the idea may be quite misleading, since over time, healthy obesity often devolves into unhealthy obesity, and the markers of health naturally worsen over time. So “healthy obesity” may not be a steady state at all – it may just be a phase that will likely deteriorate in the future.
The researchers, from University College London, looked at data over a period of 20 years – longer than any study on healthy obesity had tracked health previously. Their first group consisted of 2500 people, 66 of whom were said to be “healthy obese,” based on their metabolic profiles, which included analyses of high-density lipoprotein (“good”) cholesterol, blood pressure, fasting glucose or use of diabetes medication, triglyceride (blood fats) levels, and insulin resistance.
Of those who started out in the “healthy obese” category, over the next two decades, more than half had moved into the “unhealthy obese” category – and just 6% had lost enough weight to move into the healthy non-obese category.
The researchers then looked at a larger group of participants, consisting of 389 “healthy obese.” After 10 years, 35% had become “unhealthy obese”; after 15 years, it had risen to 38%, and to 48% after 20 years. Just 10% of the original healthy obese had lost the weight to become “healthy non-obese” after 20 years. Which prompted the authors to suggest that the “natural course of healthy obesity is progression to metabolic deterioration.”
In other words, for most people, healthy obesity is just a phase that will likely give way to unhealthy obesity in the future.
This is not the first study to suggest that healthy obesity is somewhat of a myth, at least for most people. Earlier research had found that obesity of any kind, healthy or unhealthy, increases the risk of heart disease, diabetes, cancer, and early death. What’s more, even shorter-term studies than the current one have shown that the good metabolic markers of the healthy obese do tend to deteriorate with time. “A few previous studies,” author Joshua Bell tells me, “using shorter follow-up times showed about one-third of healthy obese adults progress to unhealthy obesity. And our study with at least 10 years longer follow-up, indicates that this tendency gets stronger with time, with about half making this transition after 20 years….These results indicate that healthy obesity is often just a phase.”
Some of the healthy obese participants in the current study did remain so over time – even after 20 years, about a third of the participants still had good metabolic profiles. “However,” says Bell, “the tendency for these adults to progress to unhealthy obesity gets stronger with time… Healthy obese adults tend to get worse, not better.”
The takeaway message may be that for most people, weight loss really is the best bet: Even though markers may look good now, they may not be in 10 or 20 years’ time. A small subset of people may be obese into old age, but for the majority, obesity is linked to greater risk of a number of chronic diseases and mortality over the long term.
“Adults of any size can take steps to improve health by avoiding processed foods and embedding physical activity into daily life,” says Bell. “This can reduce harmful visceral fat, build muscle, and reduce inflammation even if weight is not initially lost. Our results stress the need to take a long-term view of healthy obesity, as healthy obese adults tend to progress to ill-health over time. Healthy obesity is still a high-risk state – the harmful effects may just be delayed.”
We’re not surprised to see the release of new information that contradicts the most recent study regarding “healthy obesity.” It’s a controversial concept so it’s possible we’ll be hearing even more conflicting information. The healthiest response to obesity is reversing the condition. We don’t need more information to figure out that concept for ourselves.