Yo-Yo weight loss
are short-term fads that both calorie
restrict & promote ketosis
with loss of water weight.
Having not learned to limit portion size
, & having felt deprived while dieting, once off the "diet" you then binge & regain lost weight. Yo-yo weight loss/regain is unhealthy. There remains no substitute for eating a balanced diet, avoiding snacks, & exercising for long-term loss.
Answer assisted by David Miller, Medical Student