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  • New research shows metabolically healthy and unhealthy ‘forms’ of obesity are linked to a greater risk of developing obesity-related cancers.
  • Doctors concluded being metabolically unhealthy is harmful to your overall health and contributes to chronic health conditions, cancer and disease.
  • To improve metabolism and treat obesity, avoid overeating, eat more plant-based foods, and consider intermittent fasting which can allow your metabolism to burn excess fat.

A growing number of studies show that obesity is a major contributing risk factor for numerous chronic health conditions.

According to new research published in the Journal of the National Cancer Institute, which will be presented at the European Congress on Obesity in Dublin, Ireland, metabolically healthy and unhealthy ‘forms’ of obesity are linked to a greater risk of developing obesity-related cancers.

For the study, researchers examined the body mass index (BMI) of nearly 800,000 European participants along with their metabolic health as it relates to obesity-related cancer risk.

To determine an individual’s metabolic health status (metabolically healthy or metabolically unhealthy) study authors collected data on their blood pressure, plasma glucose and triglycerides.

Next, they were categorized into six different groups:

  • metabolically unhealthy obesity (6.8% of individuals)
  • metabolically healthy obesity (3.4%)
  • metabolically unhealthy overweight (15.4%)
  • metabolically healthy overweight (19.8%)
  • metabolically unhealthy normal weight (12.5%)
  • metabolically healthy normal weight (42.0%)

Results showed that metabolically unhealthy women with obesity had a 21% greater risk of colon cancer, a 3 times greater risk of endometrial cancer, and a 2.5 times greater risk of kidney cancer compared to metabolically healthy women of normal weight.

The researchers also found that women with obesity, but who were metabolically healthy, also had a higher risk of certain cancers. These women had a 2.4 times greater risk of developing endometrial cancer and an 80% greater risk of kidney cancer.

For metabolically unhealthy men with obesity, they had a 2.6 times greater risk of kidney cancer, an 85% greater risk of colon cancer, and a 32% increased risk of pancreatic and rectal cancer compared to metabolically healthy men of normal weight.

Metabolically healthy men with obesity also had a 67% greater risk of kidney cancer and a 42% greater risk of colon cancer.

Both metabolically healthy and unhealthy men with overweight had nearly a 50% greater risk of the blood cancer multiple myeloma. However, metabolically healthy and unhealthy men with obesity did not have a greater risk of developing this cancer.

Dr. Holly Lofton, obesity medicine specialist and director of the medical weight management program at NYU Langone Health, agrees that the number of individuals studied is impressive.

“This study assigned a score based on the presence of hypertension, glucose aberrations, and high triglycerides in almost 800,000 Europeans,” said Lofton. “This is an impressive number of individuals to study.”

The cancer risk was similar in healthy and non-healthy normal weight patients, but among those with obesity, the metabolically unhealthy obesity patients had a higher risk of cancers.

This demonstrates an association between metabolically unhealthy obesity and cancer risk (especially, endometrial, liver and kidney cancer). The authors recommend that screening for these cancers be more aggressive in those with obesity and metabolic aberrations, Lofton explained.

Understanding potential risks related to metabolic disease and to having excess weight.

“It is a very large population-based study on obesity with 40 years follow up,” said Anton Bilchik, MD, PhD, surgical oncologist and division chair of general surgery at Providence Saint John’s Health Center and chief of medicine and Director of the Gastrointestinal and Hepatobiliary Program at Saint John’s Cancer Institute in Santa Monica. “It is an important study because it distinguishes obesity into two groups. Most studies do not. Not all obese patients have metabolic derangements. This study demonstrates that obese patients with metabolic derangements have an even higher risk of getting several cancers.”

Dr. William Li, medical doctor and New York Times bestselling author of Eat to Beat Your Diet: Burn Fat, Heal Your Metabolism, and Live Longer, told Healthline the study helps experts understand how obesity and cancer risk are related.

“This study provides additional real-world data showing the dangers of being metabolically unhealthy,” Li said. “While obesity has long been associated with increased cancer risk, the data nails the connections between metabolic health and cancer.”

The data also suggests that obesity combined with metabolic concerns increases the risk of developing obesity-related cancers more than from the total of either individual risk factor.

“Excessive body fat, especially visceral fat, leads to the metabolic complications of inflammation, high insulin levels, and increased production of insulin-like growth factor-1, which is a protein known to provoke tumor growth and accelerate the blood vessels that feed cancer cells. Thus, the study connects the dots between an unhealthy metabolic state and obesity with cancer,” Li said.

Jennifer W Bea, PhD, Cancer Prevention and Control Program Co-Leader at the University of Arizona Cancer Center, Co-Director of the Body Composition Research Laboratory, University of Arizona, said it was helpful to understand how metabolic function combined with BMI contributed to cancer risk.

“Strikingly, an increased risk of some cancer types was shown in normal-weight individuals with metabolic dysfunction,” Bea pointed out.

For example, in the study, with pancreatic cancer, there is no differentiation across the weight categories, as higher risk occurred with metabolic dysfunction (men and women combined) regardless of BMI. Bottom line, we should be looking at the biomarkers measured by the investigators even when a patient presents at a normal weight, Bea added.

There are some fundamental ways to take care of your metabolism, and often more challenging ways to treat obesity.

Experts recommend taking the following steps:

Avoid overeating

Overeating leads to metabolic complications.

Cut down or cut out factors that can trigger metabolically unhealthy obesity

This includes ultraprocessed foods, and foods with added sugar like sodas.

Eat more plant-based foods

Plant-based foods such as fresh fruits and vegetables that can help people maintain a healthy weight.

Get physical activity

Physical activity can change your body composition and metabolic profile even if you don’t lose weight, Bea pointed out.

Consult with your physician

Find out if there are any medical reasons, such as an endocrine condition, that require medications or other interventions might be needed for managing obesity and improving your metabolism.

Consider other factors

It’s also important to note that many people have causes of obesity that aren’t related to physical activity or nutrition.

“Medications, exposure to environmental toxins, sleep deprivation, and other factors may play a role in promoting obesity and/or metabolic dysfunction, so individuals may want to review multiple factors with their health providers,” Bea added.

According to new research, metabolically healthy and unhealthy ‘forms’ of obesity are linked to an increased risk of developing obesity-related cancers.

Your metabolic health is closely tied to your overall health, and being metabolically unhealthy is a risk factor for cancer and disease.

There are numerous ways to boost your metabolism and treat obesity. These include eating more plant-based foods, avoiding overeating and considering intermittent fasting which can allow your metabolism to burn excess fat.