Malnutrition could be a hidden culprit that lowers quality of life for people with larger bodies, especially if they have a health condition like osteoarthritis, University of Alberta research has found.
In a study of people with obesity and knee osteoarthritis, one in four also presented with malnutrition and, in turn, reported a worse perception of their physical function and capacity to manage their conditions on their own.

Carla Prado (Photo: Faculty of ALES)
The findings point to how the condition, defined as a combination of having low muscle mass and a high level of inflammation, is often overlooked in larger individuals, says study co-author Carla Prado, a nutrition expert in the Faculty of Agricultural, Life & Environmental Sciences and member of the Women and Children's Health Research Institute.
"We have this image of someone who has lost substantial weight and looks very thin but malnutrition is not necessarily related to being thin or having a small body weight. Having a larger body doesn't necessarily mean someone is well nourished, especially when they're living with conditions like osteoarthritis."
The study profiled the nutritional status of 46 people with obesity and advanced knee osteoarthritis, and explored associations with health outcomes, using data from the Prevention of MusclE Loss in Osteoarthritis (POMELO) study, a joint project between the U of A and Arthritis Society Canada.
The work revealed that 26 per cent of the participants had malnutrition, which represents a high rate, and of those, 13 per cent also had sarcopenic obesity a condition of low muscle mass, low muscle strength and high fat mass.

Flavio Vieira (Photo: Supplied)
In addition to confirming malnutrition as a concern for people with obesity and knee osteoarthritis, the research represents a step forward in improving the diagnostic process for them.
The study is the first to use a framework called the Global Leadership Initiative on Malnutrition (GLIM) for that particular group.
The researchers applied GLIM criteria because it provides a better assessment of a person's nutritional status by including muscle wasting a key sign of malnutrition as one of the factors, says Vieira.
"The assessment of malnutrition in clinical practice lacks standardization due to the availability of multiple diagnostic criteria; none of them are specific for obesity," he notes, adding that the typical focus is on low body weight or body mass index, which don't apply to larger people.
"By employing the GLIM consensus, we're potentially enhancing the ability to detect malnutrition in individuals with obesity."
Overall, the study findings highlight the importance of "pairing up nutritional assessment and support" when offering health care to people living with obesity and osteoarthritis, Prado says.
"Often, for example, a person will be advised to lose weight before having surgery, but that's not the best approach if we don't provide them with a targeted way to do that so they avoid losing muscle.
"Otherwise, people may lose weight in an unhealthy way, and that can create a vicious circle for them."
Study contributors included the University of California, University of Trieste, University of North Carolina, Uppsala University, Karolinska University Hospital, Sapienza University, Catholic University of Pelotas, University of Vermont and University of Toronto.