Dieting may help you to lose weight fast within short period of time. However, it maybe harmful to your body due to nutrient deficiencies. Long-term dieting can slow down your metabolism which is the main reason of Yo-Yo dieting.
Eating diet pills/ laxatives causes frequent diarrhoea. Yes you can lose weightiest but WHAT are the side effects?
i) Electrolytes imbalance -> water loss & low potassium levels etc.
ii) Gut bacterial imbalance
iii) Rely on laxatives
It is very common that people avoid eating bread or potato or pasta as they think carbs is their enemy. Each food group contains nutrients for our bodies to function. Using carbs as an example, it is a main source of energy for brain and muscle. In the long-term, you will crave for sugar and possibly this is not a sustainable way to lose weight.
Meal replacements/ “shakes” may not be suitable for everyone. If you are replacing 3 meals using shakes, you are getting ~800 calories/day (an extreme calorie restriction). It is easy to see weight rebound after a period of time. Please seek advice from a registered dietitian!
Fad diets for weight loss such as juice detox and grapefruit diet are not evidence-based. You are losing water but not fat, once you stop this diet you will gain weight back.
People often overestimates the calories they burn from physical activities. Exercise is only a small portion of daily energy deficit. Over-exercising may cause hormone fluctuation (elevated cortisol) which may be difficult to lose weight [1].
Reference:
1. Available from: https://www.healthline.com/nutrition/gaining-weight-despite-exercise#TOC_TITLE_HDR_1