This week, North America’s leading obesity researchers gathered in New Orleans for Obesity Week, their most important conference of the year.

I was there, and one of the topics that permeated the meeting was how our biases against people with obesity can be a real barrier to their health care.

It’s one reason I was taken aback by this tweet about the conference, from a doctor who specializes in caring for patients who are overweight:

Obesity Week 2016 Keynote Speakers - genetics and CICO. Our obesity 'experts' lecturing physicians. We're in good hands. #OW2016 pic.twitter.com/r4hCuJG8Ni — Dr. Jason Fung (@drjasonfung) November 2, 2016

Sadaf Farooqi, a neuroscientist at the University of Cambridge, and Kelly Brownell, dean of the public policy school at Duke University, are two of the world’s most prestigious obesity researchers. Their science has furthered our understanding of how genetics and environments can encourage this disease.

One way to interpret Dr. Jason Fung's use of the pictures and the scare quotes around expert is that the researchers' weight discredits their scholarly contributions to the field. With the sarcastic "We’re in good hands," he implied that maybe we shouldn’t trust people who struggle with their weight as truly understanding obesity.

Wait — what? We know obesity is a complex condition that develops through a combination of factors — from genes to brains, hormones, and the abundant food around us. It is not born out of moral failure or lack of willpower. Fung’s tweet feels a bit like knocking a prominent oncologist with cancer for not curing his own disease.

Fung's tweet triggered a tweetstorm from another obesity doctor, Yoni Freedhoff, who saw it as an example of the fat shaming and weight bias that have become pervasive:

1. Yesterday a semi-prominent, internet-popular, obesity clinician fat shamed two speakers at #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

2. He posted their pictures for his >14K followers w/the caption, "our 'obesity experts' lecturing physicians. We're in good hands" #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

3. His scare-quoted inference of course is that because these two experts were fat, their words weren't worth hearing #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

4. That their weights somehow erased their intellects and their quite frankly staggering contributions to the field of obesity #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

5. That their fat was the measure of their intellects, their eloquence, & their worths. Sadly, this ugly attitude is all too common #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

6. Weight-bias as a social justice issue is real having proven medical and psychological consequences #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

7. Weight hate has been shown to reduce earning potentials, affect their hiring and advancement and restricts academic advancement #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

8. It’s also been shown, when coming from healthcare providers, to reduce the quality of their medical care https://t.co/ejMkt9BnKo #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

9. The irony here is that while the speakers’ weights don’t allow for judgment as to any aspect of their lives or knowledge #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

10. this fat-shaming MD’s public attempt to discredit & humiliate them for it, speaks to his expertise and understanding of obesity #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

11. It also allows judgment of his skills and insight as a clinician, and perhaps, as a human being. #OW2016 — Yoni Freedhoff, MD (@YoniFreedhoff) November 3, 2016

I met many patients at Obesity Week, and they told me time and time again about the shame and pain at doctors’ offices because of the way their health care providers responded to their bodies, turning an appointment for the flu into a weigh-in and obesity intervention. "Going to the doctor’s office always ended in tears," one patient told me. She’d go in feeling ill, get put on a scale, and be told to lose weight. This caused her to avoid going to the doctor altogether.

And this kind of discrimination didn’t just happen in medical appointments — it’s everywhere, from the playground, to our workplaces, and the federal election campaign trail.

I asked Fung to elaborate further on his tweet, and he began with this: "Would you take financial advice from a homeless man?" He went on:

"I think that these 'experts' have the wrong paradigm of obesity — that is, genetics and calories. I think both are irrelevant to obesity. My problem is not with them personally. My problem is that they are keynote speakers and set the agenda for the entire medical profession. … Lots of people are saying that I'm fat shaming. I'm not. I'm pointing out that our current understanding of obesity is totally wrong. And I see it every day in my practice, and it kills me."

However, it looks like Fung has been fat shaming one of the two doctors he targeted in his tweet since 2013. "This guy is fat," he wrote in a blog post. "He is disciplined, hard working and an 'expert' on obesity."

It's clear that the national conversation about obesity and weight loss is rife with confusion, misperceptions, and bias. We hear it from politicians, doctors, and ordinary people. In a recent poll, the American Society for Metabolic and Bariatric Surgery captured several, including: "Americans overestimate the effectiveness of diet and exercise alone for long-term weight loss, and tend to underestimate both the safety and effectiveness of medical and surgical treatments."

The truth is obesity researchers and doctors still have a lot to learn about what obesity treatment will work for any given individual. There is no "one size fits all" solution. But at a fundamental level, if we’re going to tackle this vexing health problem, we have to start seeing obesity for what it is: a medical condition, caused by a complexity of factors, and not people’s laziness, failure, or sloth.