For quite a while some experts believed that a little extra body fat would not necessarily trigger health problems like metabolic syndrome, a cluster of diseases that often accompanies weight gain. There was even talk of an "obesity paradox," meaning that some people could derive certain benefits from being obese. But all that may just be fantasy, according to a recent study from Canada.
"Obese persons are at increased risk for adverse long-term outcomes even in the absence of metabolic abnormalities, suggesting that there is no healthy pattern of increased weight," wrote Dr. Caroline K. Kramer of Mount Sinai Hospital's Lunenfeld-Tanenbaum Research Institute in Toronto and lead author of the study report.
Whether being overweight is immediately harmful depends on a number of factors, including a person's genes, activity level, hormonal functions, and the source of calories, said Dr. David L. Katz, founder and director of the Yale University Prevention Research Center, to HealthDay. Fat accumulation, especially when it affects inner organs like the liver, can do serious damage even at low levels, he warned.
The notion that fat and fit are not necessarily exclusive of one another stems in part from studies that found overweight but physically active people to be healthier than normal-weight folks who never exercised.
Also, judging someone's health status based on body-mass index (BMI) alone has been widely criticized as an inaccurate measure in terms of overall health. Instead, most healthcare providers now prefer waist circumference as an indicator for weight-related health issues.
According to guidelines published by the National Institutes of Health (NIH), overweight people can be considered healthy if their waist size does not exceed 40 inches for men, or 35 inches for women, and if they don't have high blood pressure, high blood sugar, or high cholesterol.
However, when it comes to obesity (BMI of 30 and above), almost all studies agree that even being relatively fit cannot offset the health risks.
The issue is not so much the extra weight itself but what is called "metabolic health." For any person -- obese, overweight, or normal-weight -- to be metabolically healthy, his or her blood pressure must be less than 130/85 mmHg, triglycerides under 150 mg/dL, fasting blood sugar equal to or lower than 100 mg/dL, and HDL ("good") cholesterol above 40 mg/dL in men and 50 mg/dL in women.
But what about the so-called "obesity paradox," a finding that overweight and moderately obese patients who suffer from chronic conditions like diabetes or heart disease sometimes outlive their normal-weight counterparts with the same disease? There may be a number of explanations for this, including genetic differences and access to treatment options. Either way, the fact remains that both weight management and fitness are important factors for good health, as is dietary quality.
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