It may come as a surprise that meal replacement shakes, tummy tea and the keto diet haven't always been around.
Instead, our dieting ancestors snacked on grapefruit, boiled eggs and good old celery to lose weight. Today we return to those humble beginnings with the Military Diet.
It is the latest diet to follow, promising to help you lose up to 4.5kg in just three days of dieting.
The diet involves a strict three-day meal plan of appetising dishes including raw tuna on saltine biscuits and hard boiled eggs with cottage cheese. For those three days, you consume between 1100 and 1400 calories each day, well below the recommended daily intake for adults.
It is recommended that three-day plan is followed by four days of healthy eating. If you haven't lost all the weight in one week, then proponents also claim you can keep following the diet until you reach your goal.