Great points above and I also wanted to add:
The way to have conversations about a topic, especially an emotionally and politically charged topic like health, is not going to a random person's inbox and asking them what their health status is (or asking them to participate in a discussion of health they did not ask for tbh). Whether you're just being nosy/curious, fishing for data points to confirm your bias that fat people are unhealthy, worried about your own health because you want to gain and want a fat stranger to assuage your fears of becoming the unhealthy fat person stereotype that the fat stranger is subjected to in real life everyday, or fishing for jerk-off material, it's rude and even at our most generous and gracious interpretation, is coming from a place of ignorance. That person is not ready to participate in the discussion, they have reading and listening to do first.
"Isn’t there a space within this community to have a serious discussion about health and size?" Yes, there is, actually. Incessantly. Everywhere. In fact, can we please have a space where we DON'T talk about health, I would be begging on my hands and knees except my unhealthy body makes my knees hurt.
Another resource for research health and fatness is bigfatscience on Tumblr, inactive, but very comprehensive and links a ton of articles.
I think it is foolish to ignore so much medical research that very robustly and consistently shows that the studies that say being fat is unhealthy and weight loss is healthy are poor quality (such as skewed attrition rates, excluding data that doesn't confirm the hypothesis, or not accounting for healthcare access or socioeconomic status), biased due to funding by diet and pharmaceutical companies, and/or focus on the short term. Just for one example, and I know I bring this article up all the time but intentional weight loss is associated with increased rates of death for people with higher BMIs with diabetes diagnoses by 10 years after the attempted weight loss compared to people who did not attempt to lose weight. It's also a well known statistic that weight loss is pretty much untenable by 5y post weight loss for the vast majority of people (here's a link to an article that I'm not in the space read all of rn but it has weight regain stats based on meta-analysis of 29 studies), and once you start noticing that aaaalllll these studies about how great weight loss is end before the 5 year mark, you cannot unsee it. The medical literature on weight and health for decades now has shown us, in addition to what chz pointed out, that losing weight for health is like putting sawdust in your transmission: it sounds quieter, your health-related numbers may go closer to reference ranges, but by 5, 10+ years out, you health is now worse off than if you never lost weight. When you're educating yourself about this topic, look for meta-analyses of long-term (>5 yr) studies, and literature reviews. They can be great summaries on topics and often discuss flaws, biases, and shortcomings of existing research, which can help you learn how to spot junk studies and poorly interpreted pop science articles.
Chz touched on it, and I'm not going to get too into it because there are a lot of people who've written much more detailed and expansive info on this, but I wanted to add some perspective to your reference to "extreme sizes" affecting health and Chz's mention of access to healthcare for fat people. Some barriers to accessing medical care people close to me have experienced: emergency medical helicopter transportation couldn't fit bariatric beds, which necessitated a 2-hour ambulance ride in traffic, delaying medical care. MRI machine had an insufficient weight limit, so had to drive an hour to the closest machine they could use - not everyone has reliable transportation access or can take public transportation, so this could have caused an inability to receive or a delay in life-saving diagnostic services for someone else. Providers often don't know you need to use longer needles for intramuscular injections for vaccinations and medication administration (happened to me that the nurse and I realized my T wasn't being injected properly because the needles weren't long enough). During a Medical-ICU admission (more intensive than regular ICU) at a top-rated, well-funded research hospital, the hospital said the next treatment step should be machine-oxygenation of the blood to prevent organ and brain injury from hypoxia but they didn't have a machine that could be calibrated to work for someone with a higher weight, even though those machines exist and research shows they have a progressively stronger positive effect on outcomes in people with higher BMIs compared to people with BMIs under 25 (the study went up to >60 BMI, too). There are a million and one small and huge barriers, both practical/physical and interpersonal, to receiving preventative, emergency, and acute medical care for fat people, though, and these examples are all solely touching on physical access. How much do you think situations like these have an impact on the population health statistics of "extreme"-sized people when scaled up to a systemic and population level?
I wish there was a way to get more information on health and fatness out to more people faster in this community, because it's an interesting and complex topic, and fat people, as well as people who love fat people, in the community can be great advocates for equitable medical care and health stima around fatness, as well as empowering people to make decisions about their health in a more accurately informed way. But. It has its time and place and imo it can definitely be focused on to an excessive degree. We get it: you associate fat with unhealthy, can we please discuss other topics from time to time, too?
