What is often said on forums and what the clinical trials showed are sometimes quite different. In general on this forum the emphasis is on lowest dose possible to lose the weight and lowest dose possible to maintain the weight loss. This is aimed at minimising side effects, but not maximising beneficial effects. And results in frequently repeated posts where people ask why is this obviously inadequate low dose not working as well as I would like.
The reason that I say the evidence supports staying on the original dose is the long term follow up studies done for semaglutide and tirzepatide, where weight was maintained for up to 4 years after the weight loss on the same dose, with no trends in weight up or down, until the drug was stopped as it was a trial, and weight regain was rapid even after nearly 5 years by then. If that maintenance dose was too high, more weight loss would have occurred, and if it was too low weight gain would have occurred, and neither happened on the dose used to lose the weight. I think this is very strong evidence , these were well done large trials, that the maintenance dose is the weight loss dose. ( assuming weight loss had ceased or plateaued at that time which was the case in those studies)
One of the disadvantages of grey peptides is the lack of medical involvement and advice, an informed endocrinologist would know this, even if perhaps the average doctor might not.
Not a huge amount of research specifically on long term weight loss maintenance with GLP's has been done yet, and a lot of it attempts to use lower doses, but I have yet to see any convincing evidence from these studies that it works at lower doses, due to methodological flaws in the studies. Over years there will eventually be good research on this subject, but so far the best info is from the long term follow up on the original large scale studies.
When you lose weight , especially large amounts, your energy expenditure drops, due to having less cells using energy, and due to metabolic adaptation to long term low calorie input, so that to maintain that lower weight you have to eat less than was normal for you at that higher weight and usually less than is normal for someone of that weight who has not lost weight, and at the same time hunger increases as your body tries to return to its abnormally high weight set point. It is this combination of low energy requirements to stay weight neutral, plus extra hunger that makes maintaining weight loss long term nearly impossible, and without GLP drugs very few ever succeed.
If you have lost weight with GLP drugs, staying on them solves this problem, basically by reducing the excess hunger caused by weight loss, and for reta especially , it also boosts energy expenditure 1-200 kcal/day at higher doses, and at the same time helps to fix a lot of the metabolic abnormalities caused by obesity such as insulin resistance, which also helps with weight loss maintenance.
The other reason for staying on GLP drugs long term, especially if the obesity is or was severe is to prevent cardiovascular disease. And there is evidence that higher doses are more effective than lower doses for this. Almost by definition most people with severe obesity are already in the high risk category for cardiovascular disease, and all should check blood pressure, lipids and blood sugars to see if they need fixing as well. Staying on them prevents the development of diabetes, heart disease , stroke, about 17 different cancers, reduces blood pressure, improves lipids and blood sugars. This is proven for sema and tirz, but not yet for reta, although given how it works it is likely that it will be proven over the next few years for reta. Once you get over 40 and even more so if older, these start to be no longer abstract way off problems, the odds of heart attacks might be as high as 10-20% over the next decade, and taking steps to make this less likely is a good idea. Once damage is done it is not really reversible, ( without bypasses or stents ) and can be prevented from getting worse, but it is definitely better to prevent it in the first place. If I had taken the correct steps a decade ago or these drugs were available then, I might have been able to prevent getting heart disease, but as it is I can still try to stop it getting worse.
Losing weight is not really the hard part, most people with obesity have lost often quite a lot of weight on various diets over the years, but nearly all of them put the weight back on again, as soon as they stopped following that diet so strictly, me included.
Maintaining weight loss long term is where it gets really hard, as it requires you to eat less than your body is telling you to eat for years, and the drive to eat is very strongly built in, and very hard to oppose long term. I lost most of my weight from 145 to 75 kg without glp drugs and kept it there for a year or so, and it was not the first time, but it was difficult, and despite a very carefully designed diet to minimise hunger, I was still more or less permanently hungry. Most likely it would eventually have failed like all other times in my life, despite fairly large medical risks if I regained weight. Thankfully I managed to find a way to access GLP drugs without being rich, and it has made maintaining the weight loss much less difficult and improved the odds of maintaining it long term
