There are all sorts of conflicting ideas of ways to induce fat loss. But around 95% of them fail over the course of 3+ years. I think if there's one safe consensus among the minority 5% that succeeded in the long run (not just in inducing fat loss over a few weeks but to keep it off for years to come), it's to favor methods which are *sustainable*. And hypocaloric diets, especially ones as low as 600-800kcal/day aren't sustainable. So I'm not the type to draw the most confident conclusions in these areas since there's so much conflicting data, but I really think the safest bet is to avoid doing things you can sustain in the long run. There I do assign a fairly high degree of confidence.
[...] but I really think the safest bet is to avoid doing things you [cannot] sustain in the long run. [...]
Anything that induces, at best, temporary fat loss (as opposed to sustainable fat loss) might be at risk of adipose hyperplasia (fat cell proliferation). At least it's not something I would want to risk.
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